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HomeMy WebLinkAbout06-21-2023 AgendaHEARING EXAMINER AGENDA June 21, 2023 5:30 P.M. City Council Chambers 25 West Main Street  I. PUBLIC PARTICIPATION Public Participation Information The City of Auburn Hearing Examiner Meeting scheduled for Wednesday, June 21, 2023, at 5:30 p.m. will be held in person and virtually. To attend the meeting virtually, please click one of the below links, or call into the meeting at the phone number listed below: Join Zoom Meeting  https://us06web.zoom.us/j/87633805542  Meeting ID: 876 3380 5542  One tap mobile  +12532050468,,87633805542# US +12532158782,,87633805542# US (Tacoma) Dial by your location +1 253 205 0468 US +1 253 215 8782 US (Tacoma) 877 853 5257 US Toll‐free 888 475 4499 US Toll‐free Meeting ID: 876 3380 5542 Find your local number: https://us06web.zoom.us/u/kbzp6mqAN CASE NO: SHL22-0001 – Garden Avenue Realignment Project    APPLICANT: City of Auburn Public Works Department Kim Truong, Project Engineer 25 West Main Street Auburn, WA 98001 PROPERTY OWNER: City of Auburn 25 West Main Street Auburn, WA 98001 1 of 347 Hearing Examiner Agenda June 21, 2023 5:30 p.m. ________________________________________________________________________________ 2 REQUEST: Shoreline Substantial Development Permit (SSDP) and Critical Areas Exemption (CAO) for site preparation and construction of two roads located east of the Green River. The project will complete the east-west SE 318th Street connecting Garden Avenue (102nd Avenue SE) to 104th Avenue SE. The project site is within the “Urban Conservancy” Shoreline environment of the Green River. PROJECT LOCATION: The subject property is located at the northeast corner of the T- intersection of Garden Avenue and 8th Street NE / SE 320th Street, Auburn, WA 98092, Existing right-of-way and King County. PARCEL NO(S): King County Assessor Parcel No. 3339400621. 2 of 347 AGENDA BILL APPROVAL FORM HEARING EXAMINER Agenda Subject/Title: CP2022 Garden Avenue Realignment Project (102nd Avenue SE) City File Nos. SHL22-0001 Shoreline Substantial Dev. Permit Date: June 13, 2023 Department: Community Development DESCRIPTION: Request for Shoreline Substantial Development Permit (SSDP) for site preparation and construction of modifications to two roads located east of the Green River. ADMINISTRATIVE RECOMMENDATION: Hearing Examiner to conduct a public hearing and approve the Shoreline Substantial Development Permit. PROJECT SUMMARY: The project consists of a Shoreline Substantial Development Permit (SSDP) for site preparation and construction of modifications to two roads located east of the Green River. The project will complete the east-west SE 318th Street with roadway, pervious pavement sidewalk, curb, and gutter connecting Garden Avenue (102nd Avenue SE) herein referred to as “Garden Avenue” to 104th Avenue SE. Also, half-street improvements consisting of sidewalk and utilities will be constructed along the north-south Garden Ave terminating in a cul-de-sac at the south, eliminating vehicle connection to 8th Street NE/SE 320th Street. Approximately 2,500 square feet of pavement within the 100-foot Green River buffer will be converted to native mitigation planting south of the new cul-de-sac. The project site is within the “Urban Conservancy” Shoreline environment of the Green River. LOCATION: The subject property is located at the northeast corner of the T-intersection of Garden Avenue and 8th Street NE / SE 320th Street, Auburn, WA 98092, Existing right-of-way and King Co. Assessor Parcel No. 3339400621. Quarter Section 8 SW/Township 21 N. /Range 5 E. WM, APPLICANT: City of Auburn, Public Works Department, Kim Truong, PE, Project Engineer, 25 W Main St., Auburn, WA 98001 PROPERTY OWNER: City of Auburn, 25 W Main St., Auburn, WA 98001 EXHIBIT 1 3 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 2 of 24 Vicinity Map 2021 City of Auburn Aerial Image / Project Site Location 8th Street NE / SE 320th Street Project Area 4 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 3 of 24 The Comprehensive Plan designation, Shoreline environment designation, zoning classification and current land uses of the site and surrounding properties of the Project Site are: Comprehensive Land Use Designation Zoning Classification Shoreline Environment Designation Current Land Use Project Site Single Family Residential, 1 Dwelling Unit per Acre Urban Conservancy Single Family Residential North Single Family Residential, 1 Dwelling Unit per Acre Urban Conservancy Single Family Residences East Single Family Residential, 1 Dwelling Unit per Acre N/A Single Family Residences South Single Family Open Space Residential, 1 Dwelling Unit per Acre Open Space Urban Conservancy Single Family Residences West Single Family Open Space Residential, 1 Dwelling Unit per Acre Open Space Shoreline Residential Open Space/Green River Excerpted Comprehensive Plan Land Use Designation Map (Project Site) Project Site Single Family Open Space Multiple -Family Moderate Density Residential 5 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 4 of 24 Excerpted Zoning Classification Map (Project Site) Excerpted Shoreline Environment Designations (Project Site) Project Site Residential, 1 DU per Acre Open Space Project Site R-20 R-5 R-10 6 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 5 of 24 SEPA STATUS: A combined Notice of Application (NOA) and Determination of Non-Significance (DNS) was issued under City File No. SEP22-0021 on May 16, 2023. The comment period ended June 16, 2023 and the appeal period ends June 30, 2023. Comments received during the NOA and SEPA public comment period are provided in Exhibit 13 and 14. A copy of the SEPA Environmental Checklist, prepared by the City of Auburn, is included as Exhibit 9. FINDINGS OF FACT: Proposal Description and Site Characteristics 1. Kim Truong, PE, Applicant, as representative of the City of Auburn Public Works Department applied on October 25, 2022 for a Shoreline Substantial Development Permit (SSDP) for site preparation and construction of modifications to two roads; Garden Avenue running north/south and SE 318th Street running east/west located east of the Green River (herein referred to as the “Project”). Garden Avenue will terminate in a cul-de-sac at the south end on a City-owned vacant parcel, King County Parcel No. 3339400621. 2. The Project will have a right-of-way acquisition phase, which includes acquisition from two parcels (King County Parcel Nos. 3339400660 and 3339400655) adjacent to the proposed new east-west roadway alignment for SE 318 th Street. 3. A portion of the project site is located within the area of shoreline jurisdiction ((200 feet from the Ordinary High Water Mark (OHWM) of the Green River)). In the area of the 200-foot Shoreline jurisdiction, the Project will close off the existing Garden Avenue connection to 8th Street NE at the south terminus in a permanent cul-de-sac. There will be new half street improvements along the east side of Garden Avenue from the cul-de- sac to the new access roadway (SE 318th Street). Additionally, two (2) new parallel water mains will be installed and replace the 6” water main along Garden Avenue from 8 th Street NE to the new access roadway. The modifications to Garden Avenue at the south terminus portion of the project site are characterized by predominantly open grass and gravel abutting single-family residences to the north and east. Re-grading and revegetation mitigation will occur in the area where pavement/impervious surfaces are removed. Approximately 2,500 square feet of pavement within the 100-foot Green River buffer will be converted to native mitigation planting south of the new cul-de-sac. 4. Per Chapter ACC 16.10 the Green River is classified as a Type “S” stream (most stringent category) and is identified as a “shoreline of the state” under Chapter 90.58 RCW and the City of Auburn Shoreline Master Program (SMP). The shoreline jurisdiction of the Green River extends 200 feet from the OHWM. As outlined in SMP 4.5, Table 1 “Permitted Uses” the minimum setback from the OHWM is 100 feet in the “Urban Conservancy” shoreline environment designation which is the minimum protective vegetative buffer per ACC 16.10 to provide riparian habitat and protect water quality. The Project site will occur within 200 ft. of the Green River shoreline jurisdiction, specifically the “Urban Conservancy” shoreline environment designation. 7 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 6 of 24 5. Per ACC 15.68.100(K) channel migration zone (CMZ) “means the area within the lateral extent of likely stream channel movement due to stream bank destabilization and erosion, rapid stream incision, aggradation, avulsions, and shifts in location of stream channels.” 6. The Project extends into the Channel Migration Zone (CMZ) however, it meets the non- development criteria for an exemption from a Floodplain Permit. A Floodplain Permit Exemption (FDP22-0009) was approved by the Development Engineer Department via email (Exhibit 11) in accordance with ACC 15.68.370 (E, F, & G). The project qualifies as for an exemption under the following criteria: x “Underground and above ground utility work located in previously disturbed areas, with no significant vegetation impacts, and will have no appreciable change in grade; x Normal maintenance and preservation of public streets and private streets or parking lots (with approval of floodplain administrator), including, but not limited to, filling potholes, patching, crack seal, chip seal, repaving and installing signs and traffic signs, traffic control devices, striping/channelization, pavement markings, repair/replacement of sidewalk/curb and gutter, ADA improvements, nonmotorized improvements, repair of guardrails, repair of retaining walls, management of hazardous trees, fencing repair, lighting repair, but not including expansion of paved areas; x Public street improvements with no significant vegetation impacts, and no appreciable change in grade.” 7. In order to demonstrate compliance with the City’s Surface Water Management Manual, a Stormwater Site Plan (Exhibit 8), prepared by Consor, Inc., dated March 2023, was provided as part of the review of the application. All runoff is proposed to be infiltrated for enhanced treatment; therefore, no off-site downstream analysis is required. 8. Per the Stormwater Site Plan (Exhibit 8), the project site is within the Zone 2 groundwater protection area. Stormwater BMPs for this project site were selected to meet the minimum requirements for treatment and flow control as described in the Stormwater Management Manual for Western Washington (SWMMWW). The project will contain approximately 10,000 square feet of new sidewalk. The sidewalk is proposed to be permeable pavement to reduce site runoff and promote infiltration. 9.Per the Stormwater Site Plan (Exhibit 8) a bioretention facility was designed to treat the runoff from the new and improved road surfaces. The bioretention cell/rain garden facility will be 1,200 square feet in an 8-foot-wide strip along the northern edge of SE 318 th Street. The site will be graded such that all stormwater from impervious surfaces on the site will sheet flow from the southwest area of the project (cul-de-sac) to the northeast bioretention facility. 10.Per the Stormwater Site Plan Geotechnical Information (Exhibit 8), boring logs were completed for another project on a parcel adjacent to SE 318th Street. The boring logs have been utilized as the basis of design for this project due to proximity to the project site and as a cost saving approach for the City. The historical borings show well-draining soils with anticipated good infiltration rates in the area therefore, infiltration was selected as the primary method of flow control. The project site is not considered a high traffic area, therefore oil control BMPs are not required. 8 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 7 of 24 11. Per the Stormwater Site Plan (Exhibit 8), there are no wetlands inventoried by the City on or in the immediate vicinity of the site, and all runoff from new impervious surfaces will be captured, treated, and infiltrated. No additional wetlands protection measures are required. 12. The applicant provided a written statement describing the project. A copy of the Written Statement (Exhibit 4), prepared by Kim Truong, Project Engineer, Auburn Public Works Department, February 14, 2023. 13. The applicant provided a Cultural Resource Report, (Exhibit 7) Artifacts Consulting, Inc. dated July 6, 2011, field site number 3339400621. Data included on this historic property shows that the house built in 1907 no longer exists and the property is vacant. Cultural resources were not documented. 14. The surrounding area of the project site is characterized by large-lot single-family residences and is located in the City’s “Single-Family Residential” comprehensive plan map designation and within the R-1, Residential Zoning district – One Dwelling Unit per acre, and the “Urban Separator” overlay. 15. The Land Use Element states that the “Single-Family Residential” Land Use Designation “is the predominant land use category in the City. Maintaining and creating a diverse arrangement of interconnected subdivisions, neighborhoods, and communities that have a mix of densities and housing types; linkages with other residential areas and commercial hubs through nonmotorized modes, such as pedestrian and bicycling, and vehicular modes will be encouraged.” Per ACC 18.07.010 (C) the stated purpose of the R-1 Residential Zone-One Dwelling Unit per Acre "is to provide areas for estate-type residential development on large lots. This zone would normally be located in the areas particularly suited for such development.’ Critical Areas 16. The Applicant submitted a Critical Areas Exemption Memorandum (Exhibit 6) to request that the project be exempt from the City’s Critical Areas requirements consistent with ACC 16.10.040(A)(4) “Exemptions and Nonconforming Uses” which reads: (4) “Minor Utility and Street Projects. Utility or street projects which have minor or short duration impacts to critical areas, as determined by the director in accordance with the criteria below, and which do not significantly impact the functions or values of a critical area(s); provided, that such projects are constructed with best management practices and additional restoration measures are provided. Minor activities shall not result in the transport of sediment or increased storm water. Such allowed minor utility projects shall meet the following criteria: a. There is no practical alternative to the proposed activity with less impact on critical areas; b. The activity involves the placement of underground piping, conduit, traffic signal equipment, lighting equipment, utility pole(s), signs, anchor, or vault or other small component of a utility or street facility;” 9 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 8 of 24 However, a critical areas exemption cannot be considered for this project based on the Shoreline Master Program (SMP) as follows: “Regulation 4.4.4(1)(f) The Auburn Shoreline Master Program (SMP) states, “Activities that are exempt from the provisions of Auburn’s Critical Areas Ordinance per ACC 16.10.040 “Exemptions and nonconforming uses” shall not apply within the shoreline jurisdiction. Determining which activities are exempt shall be governed by this Master Program and WAC 173-27-040.” Additionally, an exemption to the Critical Areas permit cannot be considered for this project based on Applicability ACC 16.10.030 (A): “The provisions of this chapter shall apply to any activity that potentially affects a critical area or its buffer unless otherwise exempt.” In accordance with ACC 16.10.060: “Critical area regulations shall apply as an overlay and in addition to zoning, land use and other regulations established by the city of Auburn. In the event of any conflict between these regulations and any other regulations of the city, the regulations which provide greater protection to critical areas shall apply.” The critical areas associated with the Project are the Green River, a “Type S stream”, identified as “shorelines of the state” under Chapter 90.58 RCW and the city of Auburn shoreline master program, and Type 1 Aquifer Recharge Areas, Zone 2 groundwater protection areas established for special protection pursuant to the groundwater management program as described by Chapters 90.44, 90.48 and 90.54 RCW and Chapters 173-100 and 173-200 WAC. In accordance with ACC 16.10.110 (A): “Mitigation Standards – Adverse impacts to critical area functions and values shall be mitigated. 1.) All feasible and reasonable measures as determined by the department have been taken to reduce impacts and losses to the critical area, or to avoid impacts where avoidance is required by these regulations; 2.) The restored, created or enhanced critical area or buffer will be as viable and enduring as the critical area or buffer area it replaces; and 3.) No overall net loss will occur in wetland or stream functions and values. The mitigation shall be functionally equivalent to or greater than the altered wetland or stream in terms of hydrological, biological, physical, and chemical functions.” In accordance with ACC 16.10.110 (D): “Long-term protection of regulated wetlands, streams, wildlife habitat areas, geologically hazardous areas, aquifer recharge areas, and any associated buffer(s) shall be provided by the following method: 10 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 9 of 24 (2) “For all other developments, the critical area and its buffer shall be protected by execution of an easement dedicated to the city, a conservation organization, or land trust or similarly preserved through a permanent protective mechanism acceptable to the city. The legal description, depicted location, limitations associated with the critical area and its buffer, and access from the public street shall be included within the easement document. The easement provisions shall be reviewed and acceptable to the city prior to recording with the King County recorder.” In accordance with ACC 16.10.120 (A) In Summary - Performance standards for mitigation planning (for streams)– plants native to the Puget Lowlands or Pacific Northwest ecoregion shall be used for new plantings. Use perennial plants in preference to annual species. Use plants high in food and cover value for native fish and wildlife species. Install a temporary irrigation system and specify an irrigation schedule and responsible party to maintain unless a sufficient naturally occurring source of water is demonstrated. Include the applicant’s mitigation plan consultant in the construction process to ensure the approved mitigation plan is completed as designed. The outer perimeter of the critical area or buffer and the limits of those areas to be disturbed pursuant to an approved permit or authorization shall be marked in the field in such a way as to ensure that no unauthorized intrusion will occur. A permanent sign may be required to be installed along the boundary of the critical area or buffer along with fencing. In accordance with ACC 16.10.120 (E) In Summary - Performance standards for mitigation planning (for aquifer recharge areas) -- if hazardous substances or pesticides, herbicides, and fertilizers are use, they must be stored to prevent unauthorized discharge and applied in strict conformance with manufacturer’s instructions, respectively. Documentation procedures shall be required. Fill material used shall be documented as being free of contaminants. Implementation of protective measures will be maintained during the life of the project. In accordance with ACC 16.10.130: “For all actions requiring a mitigation plan, a monitoring program shall be prepared and implemented by the applicant to evaluate the success of the mitigation project and to determine necessary corrective actions.” Shoreline Management Program 1. The City of Auburn uses its 2020 City of Auburn Shoreline Master Program (SMP) to regulate development and management of the City’s shoreline. The road construction and utility improvements are within the 100-foot of the “Urban Conservancy” shoreline environment designation. A Shoreline Substantial Development Permit (SSDP) is required for the project because it is not considered exempt per WAC 173-27-040. Per SMP 4.5 Table 1 “Permitted Uses”, Transportation Facilities and Storm drain outfalls; primary conveyance and distribution facilities such as pipes and pump stations; accessory utility facilities to serve allowed development , are a Permitted Use. 2. Since the Project Site is within 200 feet of the OHWM along the Green River it is within the “Urban Conservancy” shoreline environment designation and thus, is within the 11 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 10 of 24 jurisdiction of the Auburn Shoreline Master Program (SMP 4.2.A). As mentioned previously, the Project is not exempt and requires a SSDP. The language of this Section provides: “4.2 Applicability. 1) The provisions of this chapter shall apply to all shorelines, shorelands and associated wetland areas covered by the Shoreline Management Act of 1971 as follows: 2) All rivers and streams and their associated wetlands downstream from a point where the mean annual flow is 20 cubic feet per second or greater. 3) All lakes and their associated wetlands which are 20 surface acres in size or larger. 4) Shorelands and associated uplands extending 200 feet in all directions as measured on a horizontal plane from the ordinary high water mark; floodways and contiguous floodplain areas landward two hundred feet from such floodways; and all wetlands and river deltas associated with their streams, lakes, and tidal waters subject to the provisions of Chapter 90.58 RCW.” 3. The applicant provided a Written Statement complying with the SSDP Application – Submittal Checklist. A copy of the Written Statement is provided as Exhibit 4. The applicant also provided a Policy Memo which explains how the project is consistent with the policies and provisions of the SMP. A copy of the Policy Memo is provided as Exhibit 5. 4. Under the State Shoreline Management Act (SMA), all development occurring within the shoreline jurisdiction area must be consistent with policies and regulations of the local SMP, as well as with the policies of the SMA. While some policies, goals, and development regulations may be referenced as findings within this staff report, additional policies, goals, and development regulations of the SMP not explicitly referenced may be found by review of the City’s 2020 SMP document. 5. Because the project requires a SSDP the Project must be found consistent with the criteria established in RCW 90.58.020, "Legislative findings—State policy enunciated— Use preference", WAC 173-27-140 "Review criteria for all development", WAC 173-27- 150 "Review criteria for substantial development permits", and SMP 6.1.7 "Application – Shoreline substantial development permit – Review criteria”. 6. The City’s rules and procedures for shoreline permits are contained in the SMP, specifically Section 6.0. The section provides the following general purpose and intent: “6.1.1 Chapter purpose and intent. It is the intention of the city council that the provisions of this chapter will promulgate and adopt a program for the administration and enforcement of a permit system that shall implement by reference the State Shoreline Management Act of 1971, Chapter 90.58 RCW; the State Department of Ecology regulations and guidelines adopted as Chapters 173-26 and 173-27 WAC; the Auburn shoreline master program attached to the ordinance codified in this chapter, together with amendments and/or additions thereto, and to provide for the implementation of the policy and standards as set forth in the aforesaid laws and 12 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 11 of 24 regulations which are by reference made a part of this chapter with the force and effect as though set out in full in this chapter.” 7. Pursuant ACC 6.1.12, the Hearing Examiner shall hold at least one public hearing on the SSDP in accordance with the following: “6.1.12 Application – Hearing – Required. A. The hearing examiner shall hold at least one public hearing on each application for a shoreline substantial development permit, shoreline conditional use permit, or shoreline variance on shorelines within the city. The public hearing shall be held not less than 30 days following the final publication of the notice required by ACC 16.08.050. B. The notice and conduct of the public hearing shall be in accordance with Chapter 2.46 ACC.” 8.The City’s rules provide the following requirements for public notice: “6.1.6 Application – Notices. The director shall give notice of the application in accordance with the applicable provisions of ACC 14.07.040, no less than 30 days prior to permit issuance. The notices shall include a statement that any person desiring to present his view to the director with regard to the application may do so in writing to the director, and any person interested in the hearing examiner's action on an application for a permit may submit his views or notify the director of his interest within 30 days of the last date of publication of the notice. Such notification or submission of views to the director shall entitle said persons to a copy of the action taken on the application.” 9. The City’s SMP contains the following information regarding the “Urban Conservancy” shoreline environment designation: “3.3 Urban Conservancy 3.3.1 Purpose: The purpose of the “Urban Conservancy” environment is to protect and restore ecological functions of open space, floodplain and other sensitive lands where they exist in urban and developed settings, while allowing a variety of compatible uses consistent with the Comprehensive Plan. 3.3.2 Designation Criteria: The Urban Conservancy environment designation is appropriate for those areas planned for development that is compatible with maintaining or restoring of the ecological functions of the area, and that are not generally suitable for intensive water-dependent uses. 3.3.3 Management Policies: The following management policies should apply to all shorelines in the Urban Conservancy Environment: 1. Primary allowed uses and their associated development standards should preserve the natural character of the area or promote preservation of open space, floodplain or sensitive lands where they exist in urban and developed 13 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 12 of 24 settings, either directly or over the long term. Uses that result in restoration of ecological functions should be allowed if the use is otherwise compatible with the purpose of the environment and the setting. 2. Standards should be established for shoreline stabilization measures, vegetation conservation, water quality, and shoreline modifications within the "urban conservancy" designation. These standards should ensure that new development does not result in a net loss of shoreline ecological functions or further degrade other shoreline values. 3.Public access and public recreation objectives should be implemented whenever feasible and significant ecological impacts can be mitigated. 4.Water-oriented uses should be given priority over nonwater-oriented uses. For shoreline areas with commercial development or adjacent to commercially navigable waters, water-dependent uses should be given highest priority. 5. Existing mining and related activities may be an appropriate use within the urban conservancy environment when conducted in a manner consistent with the environment policies and the provisions of WAC 173-26-241(3)(h) and when located consistent with mineral resource lands designation criteria pursuant to RCW 36.70A.170 and WAC 365-190-070. No new mining uses or expansion of existing mines should be permitted within the shoreline jurisdiction.” 10.The City’s SMP contains the following goals related to Circulation Element: “2.3.1 Goals 1. Achieve safe, convenient and diversified circulation systems to provide public access to the shoreline, efficient movement of people and goods, with minimum disruption to the shoreline environment and minimum conflict among shoreline uses.” 11.The City’s SMP contains the following goals related to Shoreline Use Element: “2.5.1 Goals 1. Promote the best possible pattern of land and water uses that will be most beneficial to the natural and human environments. 2.Designated Shorelines of Statewide Significance are of value to the entire State and shall be managed consistent with this recognition. In order of preference the priorities are to: a. Recognize and protect the Statewide interest over local interest; b.Preserve the natural character of the shoreline; c.Result in long term over short term benefit; d. Protect the resources and ecology of the shoreline; and, e.Increase public access to publicly owned areas of the shorelines.” 12.The City’s SMP contains the following goals related to Flood Prevention/Critical Areas: “2.8.1 Goals 1. Continue to participate in a regional approach to flood protection issues, coordinating with the State of Washington, King County, Pierce County and other entities interested in reducing flood hazards on both the White and Green Rivers. 14 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 13 of 24 2. Continue to protect wetlands, streams, wildlife habitat, and groundwater and minimize geologic hazards in the shoreline environment in accordance with the Critical Areas Ordinance.” 13.The City’s SMP contains the following policies related to Shoreline Vegetation Conservation: “4.4.2 Shoreline Vegetation Conservation 1. Developments and activities in the City’s shoreline should be planned and designed to retain native vegetation or replace shoreline vegetation with native species to achieve no net loss of the ecological functions and ecosystem-wide processes performed by vegetation. 14.The City’s SMP contains the following policies related to Critical Areas: “4.4.4 Critical Areas 1. Provide a level of protection to critical areas within the shoreline that is at least equal to that which is provided by the City’s critical areas regulations adopted pursuant to the Growth Management Act and the City’s Comprehensive Plan. If conflicts between the SMP and the critical area regulations arise, the regulations that are most consistent with the SMA or its WAC provisions will govern. 2. Allow activities in critical areas that protect and, where possible, restore the ecological functions and ecosystem-wide processes of the City’s shorelines. 3. Preserve, protect, restore and/or mitigate critical areas within and associated with the City’s shorelines to achieve no net loss of shoreline ecological functions. 4.Developments in shoreline areas that are identified as geologically hazardous areas, or pose a foreseeable risk to people and improvements during the life of the development, should not be allowed. 15.The City’s SMP contains the following policies related to Water Quality, Storm water and Non-Point Pollution: “4.4.7 Water Quality, Storm water and Non-Point Pollution 1.The City should prevent impacts to water quality and stormwater quantity that would result in a net loss of shoreline ecological functions, or a significant impact to aesthetic qualities, or recreational opportunities. 2.Stormwater management treatment, conveyance, or discharge facilities should be discouraged in the shoreline jurisdiction, unless no other feasible alternative is available. 3.Low impact development techniques that allow for greater amount of storm water to infiltrate into the soil should be encourages to reduce storm water runoff. 4.Encourage conservation of existing shoreline vegetation which provides water quality protection by slowing and filtering stormwater runoff. 16.The City’s SMP contains the following policies related to Transportation: “4.7.10 Transportation 15 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 14 of 24 1. Plan, locate, design and where appropriate construct, proposed roads, non- motorized systems and parking facilities where routes will have the least possible adverse effect on unique or fragile shoreline features, will not result in a net loss of shoreline ecological functions or adversely impact existing or planned water-dependent uses. Where other options are available and feasible, new roads or road expansions should not be built within shoreline jurisdiction. 2.The number of river crossings should be minimized. 3. Parking facilities in shorelines are not a preferred use and shall be allowed only as necessary to support an authorized use and then as remote from the shoreline as possible. 4. Trail and bicycle systems should be encouraged along the White and Green Rivers wherever possible. 5.Joint use of transportation corridors within the shoreline jurisdiction for roads, utilities, and non-motorized transportation should be encouraged. 6. New railroad corridors should be prohibited.” 17.The City’s SMP contains the following policies related to Utilities: “4.7.11 Utilities 1. Utility facilities should be designed and located to assure no net loss of shoreline ecological functions, preserve the natural landscape and vistas, preserve and protect fish and wildlife habitat, and minimize conflicts with present and planned land and shoreline uses. 2. Primary utility production and processing facilities, such as power plants, sewage treatment plants, water reclamation plants, or parts of those facilities that are non water-oriented should not be allowed in shoreline areas. 3. Utilities should utilize existing transportation and utilities sites, rights-of-way and corridors, whenever possible. Joint use of rights-of-way and corridors should be encouraged. 4. Transmission facilities for the conveyance of services, such as power lines, cables, and pipelines, shall be located outside of the shoreline area where feasible. Where no other option exists, utilities should be placed underground or alongside or under bridges. 5. New utilities facilities should be located so as not to require extensive shoreline protection structures. 6. Where storm water management, conveyance, and discharge facilities are permitted in the shoreline, they should be limited to the minimum size needed to accomplish their purpose and should be sited and designed in a manner that avoids, or mitigates adverse effects to the physical, hydrologic, or ecological functions. 7.Stormwater conveyance facilities should utilize existing transportation and utility sites, rights-of-way and corridors, whenever possible. Joint use of right- of-way and corridors should be encouraged.” Auburn Comprehensive Plan 18.Upon review of Volume 1, Single-Family Residential Designation, the policies LU-14 through LU-18 did not apply to this Project. The following City of Auburn Comprehensive Policies are relevant to the project: 16 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 15 of 24 “Volume 3, The Capital Facilities Element: Policy CF-19. The City shall consider the impacts of potential new development within the aquifer recharge areas of potable water sources as part of its environmental review process and require appropriate mitigation measures. Such mitigation may involve hydrogeological studies, testing, and/or monitoring (including monitoring wells), spill response planning, spill containment devices, sanitary sewers, and the u se of best management practices.” “Volume 3, The Capital Facilities Element, Storm Drainage: Policy CF-37. The City shall require developers to construct storm drainage improvements directly serving the development, including any necessary off-site improvements.” “Volume 3, The Capital Facilities Element, Storm Drainage: Policy CF-49. The City’s storm drainage utility shall strive to meet the environmental protection goals of the Comprehensive Plan through compliance with and implementation of the policies contained herein. Environmental issues such as water quality and fish habitat protection shall be considered in all new development applications and new storm drainage improvements.” “Volume 3, The Capital Facilities Element, Storm Drainage: Policy CF-51. The City shall seek opportunities, where feasible, to reintroduce treated urban runoff back into the groundwater system as new development and redevelopment occurs in order to minimize urbanization impacts to the hydrology of natural river systems.” Public Notice, Comments and Procedures 19.A combined Notice of Application (NOA), Determination of Non-Significance (DNS) and Notice of Public Hearing (NOH) was issued under City File No. SEP22-0021 (Exhibit 10) on May 16, 2023 and observed a 30-day comment period. The notice was mailed to property owners within 300 feet of the project site, published in the newspaper and posted on site. 20.At the time of the preparation of this report, two comments were received and are included as Exhibits 13 and 14. Background for the comments: The shoreline permit application is for a city-sponsored road construction project. However, the portion of the road project that is beyond the 200-foot area of shoreline jurisdiction was partially constructed for access to three single-family lots jointly at the time of development of the lots by a single builder: J K Monarch. This portion of the road project has a payback agreement assessed on nearby properties. There are property owners in the vicinity that are opposed to the payback agreement that was recorded on their property prior to when they purchased their lots. It is expected that these residents may provide testimony at the shoreline permit hearing related to the payback agreement. The two comments received are as follows: 17 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 16 of 24 1)Jalene King, received May 23, 2023, residing at 10387 SE 318 th Street. In summary, Ms. King is opposed to the payback agreement and believes the Garden Avenue project will create more traffic directly on to the street where she lives. ¾Staff response: Jacob Sweeting, P.E., City Engineer/Assistant Director Engineering Services responded, in summary, about the operational concerns for traffic and safety at the Garden Avenue intersection with 8th Street NE/SE 318th Street. (Exhibit 13) 2)Zac Murphy, received June 7, 2023, owner of vacant lot north of 318th Street. In summary, Mr. Murphy supports the road construction projects and enhanced vegetation planting in the Green River buffer, however, is opposed to incorporating sidewalks for the entire project, based on the area being within the “urban separator” overlay. ¾Staff response: In summary, a response was provided explaining “Complete Streets” requirement for sidewalks and the connections they provide for the walking public to transit stops and commercial areas. Further explanation was given about the King County origins of the “Urban Separator” overlay policy document and that it is implemented through the City of Auburn Comprehensive Plan by designating those areas in the urban separator overlay as low-density. The sidewalk is supported by policies and goals of the Auburn SMP, for creating public access to the shoreline. (Exhibit 14) 21.The contents of the case file for this project (SHL22-0001) are hereby incorporated by reference and made part of the record of this hearing. 22.The decision on SSDP shall be final with the Hearing Examiner and subject to the Washington State Dept. of Ecology review period as required by the following code section: “SMP 6.1.18 Grant or denial decision – Notifications. The director shall notify the following persons in writing of the hearing examiner’s final approval, disapproval or conditional approval of a substantial development permit, shoreline conditional use permit, or shoreline variance application within eight days of its final decision: A.The applicant; B.The State Department of Ecology; C. The State Attorney General; D. Any person who has submitted to the director written comments on the application; E.Any person who has written the director requesting notification.” 23.The Project has been or will be coordinated with the following agencies to ensure the project is consistent with their plans, programs, and/or regulations: x Washington State Department of Ecology 24.City of Auburn Community Development Department, and Public Works Department have reviewed the Project plans. The following City permits/approvals have been or will be secured: Substantial Development Permit (City File No. SHL22-0001) and Floodplain Development Exemption Permit (City File No. FDP22-0009). 18 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 17 of 24 CONCLUSIONS: 1. What follows are the criteria for decision-making provided in bold and italics, followed by an analysis by staff of the project’s consistency with the criteria. Critical Areas Auburn City Code provides the following review criteria for Critical Areas: ACC 16.10.110 (A) “Mitigation Standards – Adverse impacts to critical area functions and values shall be mitigated. 1.) All feasible and reasonable measures as determined by the department have been taken to reduce impacts and losses to the critical area, or to avoid impacts where avoidance is required by these regulations; 2.) The restored, created or enhanced critical area or buffer will be as viable and enduring as the critical area or buffer area it replaces; and 3.) No overall net loss will occur in wetland or stream functions and values. The mitigation shall be functionally equivalent to or greater than the altered wetland or stream in terms of hydrological, biological, physical, and chemical functions.” Staff Review: Under existing conditions, the portion of the project that is within the 100-foot buffer of the Green River mainly consists of roadway, compacted gravel shoulders and driveways, and a vacant lot that is 50% covered in compacted gravel. The project proposes to reconfigure and reconstruct a portion of the existing roadway to include a cul-de-sac and install underground water piping. More than 50% of the existing impervious surface area will be located farther away from the river as a result of the project. Approximately 2,500 square feet of the area within the 100-foot buffer will be replanted with native plantings. Overall, no net loss in stream functions and values will occur. ACC 16.10.110 (D) “Long-term protection of regulated wetlands, streams, wildlife habitat areas, geologically hazardous areas, aquifer recharge areas, and any associated buffer(s) shall be provided by the following method: (2) For all other developments, the critical area and its buffer shall be protected by execution of an easement dedicated to the city, a conservation organization, or land trust or similarly preserved through a permanent protective mechanism acceptable to the city. The legal description, depicted location, limitations associated with the critical area and its buffer, and access from the public street shall be included within the easement document. The easement provisions shall be reviewed and acceptable to the city prior to recording with the King County recorder.” Staff Review: As conditioned below, the civil plans submitted for the development shall show the 100-foot critical area buffer of the Green River and the conservation easement (or other acceptable mechanism) around the 2,500 square foot restoration area located at the south terminus of the cul-de-sac. ACC 16.10.120 (A) Performance standards for mitigation planning for streams are required. Staff Review: The applicant submitted a landscape plan for restoration of the 2,500 square foot area that will be located at the south terminus of the cul-de-sac on Garden Avenue. The 19 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 18 of 24 plantings include red flowering currant, snowberry, and low Oregon grape, plants that are perennial in nature and native to the Pacific Northwest ecoregion. As conditioned below, the area around the restored area shall be protected with fencing and critical area signage. ACC 16.10.120 (E) Performance standards for mitigation planning for aquifer recharge areas are required. Staff Review: Protective measures will be implemented as part of the project via the implementation of the Stormwater Pollution Prevention Plan (SWPP – Appendix B of the Stormwater Site Plan/Report). Existing infrastructure includes ditches along the east side of 104th Avenue that convey stormwater to a municipal storm drain, and recent improvements along SE 318th include an infiltration trench on the south side of SE 318th Street. Current topography of the project site slopes from southwest to northeast. New and replaced impervious roadway surfaces will be graded such that run-off from these areas (new cul-de-sac) will sheet flow to a bioretention cell/rain garden area on SE 318th Street with the use of drainage conveyance piping. During construction, the Spill Prevention, Control, and Countermeasures Plan (SPCC is to be provided by the Contractor prior to the start of construction) will outline the Best Management Practices (BMPs) employed to reduce pollutants in stormwater discharges from the site. The SPCC plan is intended to help prevent oil spills and lay out control and countermeasures steps should a spill occur. ACC 16.10.130, “For all actions requiring a mitigation plan, a monitoring program shall be prepared and implemented by the applicant to evaluate the success of the mitigation project and to determine necessary corrective actions...” Staff Review: As conditional below, a Monitoring Program for the Green River buffer restoration shall be submitted by the applicant and reviewed and approved by the city prior to implementation. The monitoring program shall include a contingency plan if implementation of the mitigation plan is inadequate or fails. Shoreline Substantial Development Permit 2.The Shoreline Master Program (SMP) provides the following review criteria for Shoreline Substantial Development Permits: 6.1.7 Application – Shoreline substantial development permit – Review criteria. A. A substantial development permit shall be granted by the director only when the development proposed is consistent with the following: 1. Goals, objectives, policies and use regulations of the Auburn SMP. The Project has been reviewed for consistency with the goals, objectives, policies, and use regulations of the Auburn SMP and is consistent with the following policies and regulations: Policy SMP 2.2.1(1) “Provide new and enhance existing public access to the shoreline environment.” 20 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 19 of 24 Staff review: The Project will provide a new permeable pavement sidewalk within the right-of-way along the east side of Garden Avenue and a newly planted 2,500 square foot vegetated area at the end of the cul-de-sac adjacent to the Green River. Policy SMP 2.3.1(1) “Achieve safe, convenient and diversified circulation systems to provide public access to the shoreline, efficient movement of people and good, with minimum disruption to the shoreline environment and minimum conflict among shoreline uses.” Staff review: The Project will provide better safety and traffic operation by eliminating the connection point from Garden Avenue directly onto the high traffic volume on the minor arterial of SE 320th Street. It will provide a better pedestrian walkable environment for people living north of SE 320th Street in the neighborhood and will provide calm and safe access to the shoreline. Policy SMP 3.3.3(1) “Primary allowed uses and their associated development standards should preserve the natural character of the area or promote preservation of open space, floodplain or sensitive lands where they exist in urban and developed settings, either directly or over the long term. Uses that result in restoration of ecological functions should be allowed if the use is otherwise compatible with the purpose of the environment and the setting.” Staff review: The Project site is fully developed and consists mainly of existing roadway, compacted gravel shoulders and driveways, as well as a vacant lot that is covered in compacted gravel and grass. The project proposes to reconfigure and reconstruct a portion of the existing roadway to include a cul-de-sac, permeable pavement sidewalk, and underground water piping replacement. More than half of the existing impervious area within the 100-foot buffer will be located farther away from the river at the completion of the project. Approximately 2,500 square feet of land within the 100-foot buffer will be restored to native planting enhancing the functionality of the shoreline buffer. Policy SMP 3.3.3(2) “Standards should be established for shoreline stabilization measures, vegetation conservation, water quality, and shoreline modifications within the “Urban Conservancy” designation. These standards should ensure that new development does not result in a net loss of shoreline ecological functions or further degrade other shoreline values.” Staff review: A very small amount of vegetation will be removed or altered, to include approximately 400 square feet of grass,1 fruit tree, and some small shrubs. However, the project will not further degrade shoreline ecological functions but will enhance shoreline functions by adding a permeable sidewalk and 2,500 square feet of native planting within the 100-foot buffer. Policy SMP 3.3.3(3) “Public access and public recreation objectives should be implemented whenever feasible and significant ecological impacts can be mitigated.” Staff review: The project aligns with this objective by providing a new sidewalk improving pedestrian access within the neighborhood. 21 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 20 of 24 Policy SMP 4.4.2(1) “Developments and activities in the City’s shoreline should be planned and designed to retain native vegetation or replace shoreline vegetation with native species to achieve no net loss of the ecological functions and ecosystem-wide processes performed by vegetation.” Staff review: The Project will not be expanding the existing footprint of the roadway toward the river, nor will be performing any in-water work. Therefore, existing native vegetation along the shoreline will not be disturbed. About 2,500 square feet of existing impervious surface will be restored to native plantings. Policy SMP 4.4.4(3) “Preserve, protect, restore and/or mitigate critical areas within and associated with the City’s shorelines to achieve no net loss of shoreline ecological functions.” Staff review: The Project site is located within the City’s Type 1 Aquifer Recharge Areas (Groundwater Protection Zone 2). Protective measures will be implemented as part of the project to ensure the groundwater is protected from potential contamination created by the project. Construction activities for this project are likely not susceptible to contaminate or spills due to the implementation of the Stormwater Pollution Prevention Plan (SWPP – Appendix B of the Stormwater Site Plan/Report) and the Spill Prevention, Control, and Countermeasures Plan (SPCC is to be provided by the Contractor prior to the start of construction). A SWPP is a site-specific document developed to identify potential sources of stormwater pollution at a construction site. The SWPP will outline the Best Management Practices (BMPs) employed to reduce pollutants in stormwater discharges from the site. The SPCC plan is intended to help prevent oil spills and lay out control and countermeasures steps should a spill occur. The south end of Garden Avenue is in the 100-foot Green River buffer regulated by the critical area regulations. The road will be foreshortened as much as possible removing existing extent of the roadway located in the 100-foot Green River buffer. Standard construction and best management practices will be used to contain the construction debris. Policy SMP 4.4.7(3) “Low impact development techniques that allow for greater amount of stormwater to infiltrate into the soil should be encouraged to reduce stormwater runoff.” Staff review: The new sidewalk will be constructed with permeable pavement allowing stormwater to infiltrate back into the groundwater. Additionally, about 2,500 square feet of existing impervious asphalt surface will be replaced with native plantings within the 100-foot Green River buffer reducing stormwater runoff. Currently, stormwater runoff drains to an existing infiltration trench along SE 318 th Street. The existing trench will be replaced with two new rain gardens along SE 318 th Street which will receive the stormwater runoff from the site’s impervious surfaces. Storm drainage flow will also be improved by the proposal to install new curb and gutter which directs the flow from impervious areas to the rain gardens. 22 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 21 of 24 Policy SMP 4.6.2(1) “Dredging and dredge material disposal should be done in a manner, which avoids or minimizes significant ecological impacts. Where impacts cannot be avoided, mitigation measures are required that result in no net loss of shoreline ecological functions.” Staff review: While dredging in this context usually refers to in-water work, the project proposes no in-water work. The Project will have approximately 350 tons of fill in order to backfill the trenches needed for the water improvement and for roadway improvements. The fill material will either be select imported trench backfill from nearby pit(s) unless the existing trench excavation material is deemed acceptable for use as backfill. Policy SMP 4.7.11(3) “Utilities should utilize existing transportation and utilities sites, rights-of-way and corridors, whenever possible. Joint use of rights-of-way and corridors should be encouraged.” Staff review: The new half street improvements along the east side of the road from the cul-de-sac to the new roadway with be jointly constructed with two (2) new parallel water mains and replace the 6” water main along Garden Avenue from 8th Street NE to the new east/west roadway. Regulation SMP 4.4.3(1) “To the extent Washington's State Environmental Policy Act of 1971 (SEPA), Chapter 43.21C RCW, is applicable, the analysis of environmental impacts from proposed shoreline uses or developments shall be conducted consistent with the rules implementing SEPA (Chapter 16.06 ACC and WAC 197-11).” Staff review: A combined Notice of Application (NOA) Determination of Non- Significance (DNS) and Notice of Hearing (NOH) was issued under City File No. SEP22- 0021 on May 16, 2023. SEPA’s elements of the environment were considered in reaching the threshold determination. Regulation SMP 4.4.7(2) “Development within the City’s shoreline shall conform to all requirements in the City’s Comprehensive Drainage Plan and stormwater standards, Comprehensive Plan, and Flood Hazard Area regulations.” Staff review: The Project will be regulated by the implementation of the Stormwater Pollution Prevention Plan (SWPP – Appendix B of the Stormwater Site Plan/Report) and the Spill Prevention, Control, and Countermeasures Plan (SPCC is to be provided by the Contractor prior to the start of construction). A SWPP is a site-specific document developed to identify potential sources of stormwater pollution at a construction site. The SWPP will outline the Best Management Practices (BMPs) employed to reduce pollutants in stormwater discharges from the site. 2. Auburn Comprehensive Plan and Municipal Code. 3. The Project has been reviewed for consistency with Auburn Comprehensive Plan and Auburn Municipal Code. The Project is compatible with the Capital Facilities Element. The applicant has submitted a Stormwater Site Plan that outlines the Project Overview, Existing Conditions, Off-Site Analysis and Permanent Stormwater Control Plan that address the 23 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 22 of 24 impacts of new development, aquifer recharge areas, storm drainage improvements, and low impact development strategies to minimize urbanization impacts to the hydrology of natural river systems. 3. The policies, guidelines, and regulations of the SMA (Chapter 90.58 RCW; Chapters 173-26 and 173-27 WAC). By meeting the criteria established within the City of Auburn’s SMP, which was most recently approved by the Washington State Department of Ecology on May 7, 2020, the project will be consistent with the state SMA. B. The director may attach conditions to the approval of permits as necessary to assure consistency of the proposal with the above criteria. Conditions are provided under "Recommended Conditions of Approval" below. Staff finds that the proposal is consistent with the above criteria for a Shoreline Substantial Development Permit and the criteria outlined in WAC 173-27-150. Consistency with SMA & Local SMP 1. The Shoreline Management rules (WAC 173-27-140) set forth the following two criteria provided for all developments within the shoreline jurisdiction. “(A) No authorization to undertake use or development on shorelines of the state shall be granted by the local government unless upon review the use or development is determined to be consistent with the policy and provisions of the Shoreline Management Act and the master program.” “(B) No permit shall be issued for any new or expanded building or structure of more than thirty-five feet above average grade level on shorelines of the state that will obstruct the view of a substantial number of residences on areas adjoining such shorelines except where a master program does not prohibit the same and then only when overriding considerations of the public interest will be served.” As provided in Conclusions 1, 2 and 3, the Project meets the criteria established within the City of Auburn’s SMP, which was most recently approved by the Washington State Department of Ecology on May 7, 2020, the project will be consistent with the state SMA. The Project will not obstruct the view of area residences. The purpose of the Project is to provide better safety and traffic operation by eliminating the connection point from Garden Avenue directly onto the high traffic volume on the minor arterial of SE 320th Street. It will provide a better pedestrian walkable environment for people living north of SE 320th Street in the neighborhood and will provide calm and safe access to the shoreline. Erosion control measures consistent with City standards and Best Management Practices (BMPs) will be implemented during construction. BMPs used to control erosion will include, but are not limited to, inlet protection, street sweeping, and temporary cover measures. A Temporary Erosion and Sediment Control (TESC) plan will be developed for this project. 24 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 23 of 24 The City is in agreement with the analysis of the Best Management Practices that will be utilized for this Project and with the criteria established in WAC 173-27-140. 2. The Shoreline Management rules in WAC 173-27-150 set forth the following criteria that must be met for approval of a Shoreline Substantial Development Permit. The Project must be consistent with: (1) A substantial development permit shall be granted only when the development proposed is consistent with: (a) The policies and procedures of the act; (b) The provisions of this regulation; and (c) The applicable master program adopted or approved for the area. Provided, that where no master program has been approved for an area, the development shall be reviewed for consistency with the provisions of chapter 173-26 WAC, and to the extent feasible, any draft or approved master program which can be reasonably ascertained as representing the policy of the local government. (2) Local government may attach conditions to the approval of permits as necessary to assure consistency of the project with the act and the local master program. As noted previously within the above analysis outlined within Conclusion 2, City of Auburn staff believe the project is consistent with the criteria established in WAC 173-27-150. STAFF RECOMMENDATION: Based on the information contained in this Staff Report, the attached exhibits, Staff recommend that the Hearing Examiner APPROVE the Shoreline Substantial Development Permit subject to the conditions provided below. RECOMMENDED CONDITIONS OF APPROVAL: 1. Development pursuant to a substantial development permit shall not begin and shall not be authorized until 21 days from the date the director files the approved substantial development permit with the State Department of Ecology and Attorney General, or until all review proceedings initiated within 21 days of the date of such filing have been terminated. (SMP 6.1.19) 2. Construction or substantial progress toward construction of a project for which a permit has been granted pursuant to the Auburn SMP must be undertaken within two years after permit approval. (SMP 6.1.21) 3. Project mitigation shall be substantially consistent with the Stormwater Site Plan provided in the Garden Ave. Realignment Stormwater Site Plan, Consor, Inc., revision dated March 2023 (Exhibit 8) for the project. 4. In accordance with ACC 16.10.110(D) the civil plans submitted for the development shall show the 100-foot critical area buffer of the Green River and the conservation easement or other acceptable mechanism around the 2,500 square foot restoration area located at the south terminus of the cul-de-sac. The area between the path (leading from the cul- de-sac to SE 320th Street) and 100 Shoreline buffer (approximate 1,800 square foot) shall also be restored in plantings with less intensive groupings than the restoration west of the path. 25 of 347 Staff Member: Dinah Reed Date: June 13, 2023 Page 24 of 24 5. In accordance with ACC 16.10.120(A) The restored 2,500 square foot area shall be protected with critical area open rail fencing and signage as appropriate. 6. In accordance with ACC 16.10.130 a Monitoring Program for the Green River buffer restoration shall be submitted by the applicant and reviewed and approved by the city prior to implementation. The monitoring program shall include a contingency plan if implementation of the mitigation plan is inadequate or fails. 7. In accordance with ACC 16.10.120 Performance standards and maintenance of the mitigation sites during the initial 5-year monitoring period will be the responsibility of the City of Auburn Public Works Department. Staff reserves the right to supplement the record of the case to respond to matters and information raised subsequent to the writing of this report. EXHIBIT LIST: Exhibit 1 Staff Report Exhibit 2 Completed City of Auburn Land Use Application Forms, City of Auburn Exhibit 3 Joint Aquatic Resources Permit Application (JARPA) form, City of Auburn Exhibit 4 Written Statement, City of Auburn Exhibit 5 SMP Policy Memo, City of Auburn, dated February 14, 2023 Exhibit 6 Critical Areas Exemption Memorandum for CAO22-0010, dated January 4, 2023 Exhibit 7 Cultural Resources Report, Artifacts Consulting, Inc., dated July 6, 2011 Exhibit 8 Stormwater Site Plan Report, Consor, Inc., revision dated March 2023 Exhibit 9 SEPA Environmental Checklist, City of Auburn, revision dated February 16, 2023 Exhibit 10 Notice of Application (NOA), Determination of Non-Significance (DNS), and Notice of Public Hearing (NOH) Exhibit 11 Floodplain Permit Exemption Approval for FDP22-0009 Exhibit 12 Site Plan and Landscape Plan, revised March 27, 2023 Exhibit 13 Jalene King comment email dated May 23, 2023 (neighboring property owner) and City response dated June 8, 2023 Exhibit 14 Zac Murphy comment email dated June 7, 2023 (neighboring property owner) and City response dated June 13, 2023 26 of 347 Page 1 of 2 CITY OF AUBURN Land Use Application #1216312 - Garden Avenue Realignment 27 of 347 EXHIBIT 2 Project Contact Company Name:City of Auburn Name:Kim Truong Email:kbtruong@auburnwa.gov Address:25 West Main St.Phone #:(206) 804-5059 Auburn WA 98001 Project Type Activity Type Scope of Work New None Shoreline Project Name:Garden Avenue Realignment Description of Work: Fully construct SE 318th St with roadway, sidewalk, curb and gutter connecting Garden Ave to 104th Ave. Half-street improvements along the east side of Garden Ave with a culdesac at the end of Garden Ave cutting off direct connection onto 8th St. There will also be utilities improvements. Project Details Development Activity Shoreline Substantial Development Page 2 of 2 CITY OF AUBURN Land Use Application #1216312 - Garden Avenue Realignment 28 of 347 ORIA-revised 02/2020 Page 1 of 16 WASHINGTON STATE Joint Aquatic Resources Permit Application (JARPA) Form1,2 [help] USE BLACK OR BLUE INK TO ENTER ANSWERS IN THE WHITE SPACES BELOW. Part 1–Project Identification 1.Project Name (A name for your project that you create. Examples: Smith’s Dock or Seabrook Lane Development) [help] Garden Avenue Realignment Part 2–Applicant The person and/or organization responsible for the project. [help] 2a. Name (Last, First, Middle) Nancy Backus (Mayor) 2b. Organization (If applicable) City of Auburn 2c. Mailing Address (Street or PO Box) 25 West Main St. 2d. City, State, Zip Auburn, WA 98001 2e. Phone (1)2f. Phone (2)2g. Fax 2h. E-mail 253-931-3041 1Additional forms may be required for the following permits: ·If your project may qualify for Department of the Army authorization through a Regional General Permit (RGP), contact the U.S. Army Corps of Engineers for application information (206) 764-3495. ·Not all cities and counties accept the JARPA for their local Shoreline permits. If you need a Shoreline permit, contact the appropriate city or county government to make sure they accept the JARPA. 2To access an online JARPA form with [help] screens, go to http://www.epermitting.wa.gov/site/alias__resourcecenter/jarpa_jarpa_form/9984/jarpa_form.aspx. For other help, contact the Governor’s Office for Regulatory Innovation and Assistance at (800) 917-0043 or help@oria.wa.gov. AGENCY USE ONLY Date received: Agency reference #: Tax Parcel #(s): 29 of 347 EXHIBIT 3 ORIA-revised 02/2020 Page 2 of 16 Part 3–Authorized Agent or Contact Person authorized to represent the applicant about the project. (Note: Authorized agent(s) must sign 11b of this application.) [help] 3a. Name (Last, First, Middle) Kim Truong 3b. Organization (If applicable) City of Auburn 3c. Mailing Address (Street or PO Box) 25 West Main St. 3d. City, State, Zip Auburn, WA 98001 3e. Phone (1)3f. Phone (2)3g. Fax 3h. E-mail 253-804-5059 253-931-3010 kbtruong@auburnwa.gov Part 4–Property Owner(s) Contact information for people or organizations owning the property(ies) where the project will occur. Consider both upland and aquatic ownership because the upland owners may not own the adjacent aquatic land. [help] ☒Same as applicant. (Skip to Part 5.) ☒Repair or maintenance activities on existing rights-of-way or easements. (Skip to Part 5.) ☐There are multiple upland property owners. Complete the section below and fill out JARPA Attachment A for each additional property owner. ☐Your project is on Department of Natural Resources (DNR)-managed aquatic lands. If you don’t know, contact the DNR at (360) 902-1100 to determine aquatic land ownership. If yes, complete JARPA Attachment E to apply for the Aquatic Use Authorization. 4a. Name (Last, First, Middle) City of Auburn 4b. Organization (If applicable) City of Auburn 4c. Mailing Address (Street or PO Box) 25 West Main St. 4d. City, State, Zip Auburn, WA 98001 4e. Phone (1)4f. Phone (2)4g. Fax 4h. E-mail 253-931-3010 30 of 347 ORIA-revised 02/2020 Page 3 of 16 Part 5–Project Location(s) Identifying information about the property or properties where the project will occur. [help] ☐There are multiple project locations (e.g. linear projects). Complete the section below and use JARPA Attachment B for each additional project location. 5a. Indicate the type of ownership of the property. (Check all that apply.) [help] ☐Private ☐Federal ☒Publicly owned (state, county, city, special districts like schools, ports, etc.) ☐Tribal ☐Department of Natural Resources (DNR) – managed aquatic lands (Complete JARPA Attachment E) 5b. Street Address (Cannot be a PO Box. If there is no address, provide other location information in 5p.) [help] Garden Avenue and SE 318th St. 5c. City, State, Zip (If the project is not in a city or town, provide the name of the nearest city or town.) [help] Auburn, WA 98002 5d. County [help] King 5e. Provide the section, township, and range for the project location. [help] ¼ Section Section Township Range SW 08 21 05 5f. Provide the latitude and longitude of the project location. [help] ·Example: 47.03922 N lat. / -122.89142 W long. (Use decimal degrees - NAD 83) 47.31625/-122.20574 5g. List the tax parcel number(s) for the project location. [help] ·The local county assessor’s office can provide this information. N/A 5h. Contact information for all adjoining property owners. (If you need more space, use JARPA Attachment C.) [help] Name Mailing Address Tax Parcel # (if known) Timothy M Wells 31831 102nd AVE SE 3339400770 Auburn, WA 98092 Joyce F Kollars 31705 102nd AVE SE 3339400771 Auburn, WA 98092 City of Auburn 25 West Main St. 3339400621 & 3339400635 Auburn, WA 98001 Loan T Nguyen and Tai V Trinh 31838 102nd AVE SE 3339400634 Auburn, WA 98092 31 of 347 ORIA-revised 02/2020 Page 4 of 16 5i. List all wetlands on or adjacent to the project location. [help] N/A 5j. List all waterbodies (other than wetlands) on or adjacent to the project location. [help] Green River 5k. Is any part of the project area within a 100-year floodplain? [help] ☒ Yes ☐ No ☐ Don’t know 5l. Briefly describe the vegetation and habitat conditions on the property. [help] Various type of small brushes, shrubs and small trees along the shoulder of the existing roadway. 5m. Describe how the property is currently used. [help] The area of the overall project is characterized by large-lot single family development as a historic development along the east side of the Green River within a river bend. The area has a comprehensive plan designation of “Single Family Residential” with an “Urban Separator Overlay”. The zoning of the project area is outside the immediate riverbanks is R-1, Residential one dwelling units per acre. The immediate riverbanks have a comprehensive Plan designation of “Open Space” and a zoning of OS, Open Space. The general area is part of the relatively flat river floodplain at the base of Lea Hill. The area is predominantly open grass land and maintained grass areas between houses along north-south aligned local streets as part of the maintained residential yards. There are scattered isolated trees within this project area. As viewed by aerial photos, the immediate riverbanks appear to be naturally-occurring tree cover. The tree cover appears predominantly deciduous trees as early successional forest vegetation. The most significant area of vegetation is at the north end of Garden Ave (102nd Ave SE) at the apex of the river bend. The band of riverbank vegetation is narrower at the south end of the project where structures and maintained yards are closer to the riverbanks. 5n. Describe how the adjacent properties are currently used. [help] Adjacent properties are single residential homes. 5o. Describe the structures (above and below ground) on the property, including their purpose(s) and current condition. [help] 32 of 347 ORIA-revised 02/2020 Page 5 of 16 This is a public street that is travelled by vehicles and pedestrians with private utility poles along the roadway. There are existing private and public underground utilities. All structures are in fair to good condition. 5p. Provide driving directions from the closest highway to the project location, and attach a map. [help] On WA-18 W Take the WA-164 E exit toward Auburn Turn right onto Auburn Way S Turn right onto 4th St SE Turn left onto M St SE Turn right onto 8th St NE Part 6–Project Description 6a. Briefly summarize the overall project. You can provide more detail in 6b. [help] Fully construct SE 318th St with roadway, sidewalk, curb and gutter connecting Garden Ave to 104th Ave. Half-street improvements along the east side of Garden Ave with a cul-de-sac at the end of Garden Ave cutting off direct connection onto 8th St. There will also be utilities improvements. 6b. Describe the purpose of the project and why you want or need to perform it. [help] The purpose of this project is to provide better safety and traffic operation by eliminating the connection point from Garden Ave directly onto the high traffic volume on 8th St. NE and providing an east-west connection on to 104th St. It also provides better pedestrian routes with established sidewalks and illuminated streets with new street lighting system. 6c. Indicate the project category. (Check all that apply) [help] ☐Commercial ☐Residential ☐Institutional ☒Transportation ☐Recreational ☐Maintenance ☐Environmental Enhancement 6d. Indicate the major elements of your project. (Check all that apply) [help] ☐Aquaculture ☐Bank Stabilization ☐Boat House ☐Boat Launch ☐Boat Lift ☐Bridge ☐Bulkhead ☐Buoy ☐Culvert ☐Dam / Weir ☐Dike / Levee / Jetty ☐Ditch ☐Dock / Pier ☐Dredging ☐Fence ☐Ferry Terminal ☐Float ☐Floating Home ☐Geotechnical Survey ☐Land Clearing ☐Marina / Moorage ☐Mining ☐Outfall Structure ☐Piling/Dolphin ☐Retaining Wall (upland) ☒Road ☐Scientific Measurement Device ☐Stairs ☒Stormwater facility ☐Swimming Pool ☒Utility Line 33 of 347 ORIA-revised 02/2020 Page 6 of 16 ☐Channel Modification ☐Fishway ☐Raft ☐Other: 34 of 347 ORIA-revised 02/2020 Page 7 of 16 6e. Describe how you plan to construct each project element checked in 6d. Include specific construction methods and equipment to be used. [help] ·Identify where each element will occur in relation to the nearest waterbody. ·Indicate which activities are within the 100-year floodplain. The preliminary construction sequencing is to perform street improvements (roadway, sidewalk, driveways, drainage system, etc) along SE 318th St to provide access for residents in the neighborhood. Then once SE 318th St is constructed, direct connection from Garden Ave to 8th St NE will be eliminated. Underground water and street improvements along Garden Ave will occur next. All the construction activities proposed will use standard construction methods and equipment. There is a small portion of construction activities planned to occur within the channel migration zone. See site map. 6f. What are the anticipated start and end dates for project construction? (Month/Year) [help] ·If the project will be constructed in phases or stages, use JARPA Attachment D to list the start and end dates of each phase or stage. Start Date: 4/1/2023 Construction will happen within this date range depending on permits approval and right-of- way acquisition. End Date: 10/30/2023 ☐See JARPA Attachment D 6g. Fair market value of the project, including materials, labor, machine rentals, etc. [help] Anticipated construction cost is $1.2 million. 6h. Will any portion of the project receive federal funding? [help] ·If yes, list each agency providing funds. ☐Yes ☒ No ☐ Don’t know Part 7–Wetlands: Impacts and Mitigation ☐Check here if there are wetlands or wetland buffers on or adjacent to the project area. (If there are none, skip to Part 8.) [help] 7a. Describe how the project has been designed to avoid and minimize adverse impacts to wetlands. [help] ☐Not applicable 7b. Will the project impact wetlands? [help] ☐Yes ☐ No ☐ Don’t know 35 of 347 ORIA-revised 02/2020 Page 8 of 16 7c. Will the project impact wetland buffers? [help] ☐Yes ☐ No ☐ Don’t know No wetland or their buffers will be affected. The nearest wetland is approx. 800ft away. 7d. Has a wetland delineation report been prepared? [help] ·If Yes, submit the report, including data sheets, with the JARPA package. ☐Yes ☐ No 7e. Have the wetlands been rated using the Western Washington or Eastern Washington Wetland Rating System? [help] ·If Yes, submit the wetland rating forms and figures with the JARPA package. ☐Yes ☐ No ☐ Don’t know 7f. Have you prepared a mitigation plan to compensate for any adverse impacts to wetlands? [help] ·If Yes, submit the plan with the JARPA package and answer 7g. ·If No, or Not applicable, explain below why a mitigation plan should not be required. ☐Yes ☐ No ☐ Don’t know 7g. Summarize what the mitigation plan is meant to accomplish, and describe how a watershed approach was used to design the plan. [help] 7h. Use the table below to list the type and rating of each wetland impacted, the extent and duration of the impact, and the type and amount of mitigation proposed. Or if you are submitting a mitigation plan with a similar table, you can state (below) where we can find this information in the plan. [help] Activity (fill, drain, excavate, flood, etc.) Wetland Name1 Wetland type and rating category2 Impact area (sq. ft. or Acres) Duration of impact3 Proposed mitigation type4 Wetland mitigation area (sq. ft. or acres) 1 If no official name for the wetland exists, create a unique name (such as “Wetland 1”). The name should be consistent with other project documents, such as a wetland delineation report. 36 of 347 ORIA-revised 02/2020 Page 9 of 16 2 Ecology wetland category based on current Western Washington or Eastern Washington Wetland Rating System. Provide the wetland rating forms with the JARPA package. 3 Indicate the days, months or years the wetland will be measurably impacted by the activity. Enter “permanent” if applicable. 4 Creation (C), Re-establishment/Rehabilitation (R), Enhancement (E), Preservation (P), Mitigation Bank/In-lieu fee (B) Page number(s) for similar information in the mitigation plan, if available: 7i. For all filling activities identified in 7h, describe the source and nature of the fill material, the amount in cubic yards that will be used, and how and where it will be placed into the wetland. [help] 7j. For all excavating activities identified in 7h, describe the excavation method, type and amount of material in cubic yards you will remove, and where the material will be disposed. [help] Part 8–Waterbodies (other than wetlands): Impacts and Mitigation In Part 8, “waterbodies” refers to non-wetland waterbodies. (See Part 7 for information related to wetlands.) [help] ☒Check here if there are waterbodies on or adjacent to the project area. (If there are none, skip to Part 9.) 8a. Describe how the project is designed to avoid and minimize adverse impacts to the aquatic environment. [help] ☐Not applicable The project will not be expanding the existing footprint of the roadway toward the river, nor will we be performing any in-water work. Standard construction and best management practices will be used to contain the construction debris to prevent it from leaving the bridge surface. Adverse impacts to the aquatic environment are not anticipated. The south end of Garden Ave is in the 100-foot Green River buffer regulated by the critical area regulations. With the project the road will be foreshortened as much as possible to remove more of the existing extent of roadway that is located within in the 100-foot green River Buffer to increase conformity with 100-foot critical area buffer and the area restored. A critical areas exemption is being applied to where re-vegetation will be prepared for the restored buffer area. 8b. Will your project impact a waterbody or the area around a waterbody? [help] ☒Yes ☐ No 37 of 347 ORIA-revised 02/2020 Page 10 of 16 8c. Have you prepared a mitigation plan to compensate for the project’s adverse impacts to non-wetland waterbodies? [help] ·If Yes, submit the plan with the JARPA package and answer 8d. ·If No, or Not applicable, explain below why a mitigation plan should not be required. ☒Yes ☐ No ☐ Don’t know The project will not be expanding the existing footprint of the roadway toward the river, nor will we be performing any in-water work. Adverse impacts to the aquatic environment are not anticipated. Construction activities are proposed in area which is already a developed area. Adverse impacts to non-wetland waterbodies are not anticipated. 8d. Summarize what the mitigation plan is meant to accomplish. Describe how a watershed approach was used to design the plan. ·If you already completed 7g you do not need to restate your answer here. [help] Approximately, 2,500sf area will be converted from impervious asphalt pavement to native mitigation planting within the 100ft Green River buffer. The planting schedule consists of native plants and shrubs at the spacing recommended. See landscaping plan. 8e. Summarize impact(s) to each waterbody in the table below. [help] Activity (clear, dredge, fill, pile drive, etc.) Waterbody name1 Impact location2 Duration of impact3 Amount of material (cubic yards) to be placed in or removed from waterbody Area (sq. ft. or linear ft.) of waterbody directly affected 1 If no official name for the waterbody exists, create a unique name (such as “Stream 1”) The name should be consistent with other documents provided. 2 Indicate whether the impact will occur in or adjacent to the waterbody. If adjacent, provide the distance between the impact and the waterbody and indicate whether the impact will occur within the 100-year flood plain. 3 Indicate the days, months or years the waterbody will be measurably impacted by the work. Enter “permanent” if applicable. 8f. For all activities identified in 8e, describe the source and nature of the fill material, amount (in cubic yards) you will use, and how and where it will be placed into the waterbody. [help] 38 of 347 ORIA-revised 02/2020 Page 11 of 16 8g. For all excavating or dredging activities identified in 8e, describe the method for excavating or dredging, type and amount of material you will remove, and where the material will be disposed. [help] Part 9–Additional Information Any additional information you can provide helps the reviewer(s) understand your project. Complete as much of this section as you can. It is ok if you cannot answer a question. 9a. If you have already worked with any government agencies on this project, list them below. [help] Agency Name Contact Name Phone Most Recent Date of Contact City of Auburn Jeff Dixon 253-804-5033 10/13/2022 City of Auburn Alexandria Teague 253-931-3003 10/13/2022 9b. Are any of the wetlands or waterbodies identified in Part 7 or Part 8 of this JARPA on the Washington Department of Ecology’s 303(d) List? [help] ·If Yes, list the parameter(s) below. ·If you don’t know, use Washington Department of Ecology’s Water Quality Assessment tools at: https://ecology.wa.gov/Water- Shorelines/Water-quality/Water-improvement/Assessment-of-state-waters-303d. ☒Yes ☐ No Temperature and Dissolved Oxygen. 9c. What U.S. Geological Survey Hydrological Unit Code (HUC) is the project in? [help] ·Go to http://cfpub.epa.gov/surf/locate/index.cfm to help identify the HUC. 17 9d. What Water Resource Inventory Area Number (WRIA #) is the project in? [help] ·Go to https://ecology.wa.gov/Water-Shorelines/Water-supply/Water-availability/Watershed-look-up to find the WRIA #. 9 39 of 347 ORIA-revised 02/2020 Page 12 of 16 9e. Will the in-water construction work comply with the State of Washington water quality standards for turbidity? [help] ·Go to https://ecology.wa.gov/Water-Shorelines/Water-quality/Freshwater/Surface-water-quality-standards/Criteria for the standards. ☐Yes ☐ No ☒ Not applicable 9f. If the project is within the jurisdiction of the Shoreline Management Act, what is the local shoreline environment designation? [help] ·If you don’t know, contact the local planning department. ·For more information, go to: https://ecology.wa.gov/Water-Shorelines/Shoreline-coastal-management/Shoreline-coastal- planning/Shoreline-laws-rules-and-cases. ☒Urban ☐ Natural ☐ Aquatic ☒ Conservancy ☒Other: Shoreline Residential 9g. What is the Washington Department of Natural Resources Water Type? [help] ·Go to http://www.dnr.wa.gov/forest-practices-water-typing for the Forest Practices Water Typing System. ☐Shoreline ☒ Fish ☐Non-Fish Perennial ☐ Non-Fish Seasonal 9h. Will this project be designed to meet the Washington Department of Ecology’s most current stormwater manual? [help] ·If No, provide the name of the manual your project is designed to meet. ☒Yes ☐ No Name of manual: And the City of Auburn Supplemental Manual 9i. Does the project site have known contaminated sediment? [help] ·If Yes, please describe below. ☐Yes ☒ No 9j. If you know what the property was used for in the past, describe below. [help] 9k. Has a cultural resource (archaeological) survey been performed on the project area? [help] ·If Yes, attach it to your JARPA package. ☐Yes ☒ No An assessment was performed using the Washington DAHP website and no significant finding was found. The results is attached. 40 of 347 ORIA-revised 02/2020 Page 13 of 16 41 of 347 ORIA-revised 02/2020 Page 14 of 16 9l. Name each species listed under the federal Endangered Species Act that occurs in the vicinity of the project area or might be affected by the proposed work. [help] According to IPaC, the following is a list of potential endangered/threatened species in the project vicinity: ·Gray Wolf (Proposed Endangered) ·Marbled Murrelet (Threatened) ·Streaked Horned Lark (Threatened) ·Yellow-Billed Cuckoo (Threatened) ·Bull Trout (Threatened) 9m. Name each species or habitat on the Washington Department of Fish and Wildlife’s Priority Habitats and Species List that might be affected by the proposed work. [help] The following species and habitats, as identified by the Washington Department of Fish and Wildlife’s Priority Habitats and Species List (PHS), are in the immediate vicinity of the project: ·Chum ·Dolly Varden/Bull Trout ·Coho ·Chinook ·Steelhead ·Resident Coastal Cutthroat ·Pink Salmon Odd Year ·Sockeye ·Rainbow Trout However, there are no anticipated impacts to species or habitats listed as there is no in-water work proposed and the work will be entirely contained on the existing bridge surface. Part 10–SEPA Compliance and Permits Use the resources and checklist below to identify the permits you are applying for. ·Online Project Questionnaire at http://apps.oria.wa.gov/opas/. ·Governor’s Office for Regulatory Innovation and Assistance at (800) 917-0043 or help@oria.wa.gov. ·For a list of addresses to send your JARPA to, click on agency addresses for completed JARPA. 10a. Compliance with the State Environmental Policy Act (SEPA). (Check all that apply.) [help] ·For more information about SEPA, go to https://ecology.wa.gov/regulations-permits/SEPA-environmental-review. ☐A copy of the SEPA determination or letter of exemption is included with this application. ☒A SEPA determination is pending with City of Auburn (lead agency). The expected decision date is March 2023 . ☐I am applying for a Fish Habitat Enhancement Exemption. (Check the box below in 10b.) [help] 42 of 347 ORIA-revised 02/2020 Page 15 of 16 ☐This project is exempt (choose type of exemption below). ☐Categorical Exemption. Under what section of the SEPA administrative code (WAC) is it exempt? ☐Other: ☐SEPA is pre-empted by federal law. 10b. Indicate the permits you are applying for. (Check all that apply.) [help] LOCAL GOVERNMENT Local Government Shoreline permits: ☒Substantial Development ☐ Conditional Use ☐ Variance ☐Shoreline Exemption Type (explain): Other City/County permits: ☐Floodplain Development Permit ☐ Critical Areas Ordinance STATE GOVERNMENT Washington Department of Fish and Wildlife: ☐Hydraulic Project Approval (HPA) ☐ Fish Habitat Enhancement Exemption – Attach Exemption Form Washington Department of Natural Resources: ☐Aquatic Use Authorization Complete JARPA Attachment E and submit a check for $25 payable to the Washington Department of Natural Resources. Do not send cash. Washington Department of Ecology: ☐Section 401 Water Quality Certification ☐Non-Federally Regulated Waters FEDERAL AND TRIBAL GOVERNMENT United States Department of the Army (U.S. Army Corps of Engineers): ☐Section 404 (discharges into waters of the U.S.) ☐ Section 10 (work in navigable waters) United States Coast Guard: For projects or bridges over waters of the United States, contact the U.S. Coast Guard at: d13-pf-d13bridges@uscg.mil ☐Bridge Permit ☐Private Aids to Navigation (or other non-bridge permits) United States Environmental Protection Agency: ☐Section 401 Water Quality Certification (discharges into waters of the U.S.) on tribal lands where tribes do not have treatment as a state (TAS) Tribal Permits: (Check with the tribe to see if there are other tribal permits, e.g., Tribal Environmental Protection Act, Shoreline Permits, Hydraulic Project Permits, or other in addition to CWA Section 401 WQC) ☐Section 401 Water Quality Certification (discharges into waters of the U.S.) where the tribe has treatment as a state (TAS). 43 of 347 ORIA-revised 02/2020 Page 16 of 16 Part 11–Authorizing Signatures Signatures are required before submitting the JARPA package. The JARPA package includes the JARPA form, project plans, photos, etc. [help] 11a. Applicant Signature (required) [help] I certify that to the best of my knowledge and belief, the information provided in this application is true, complete, and accurate. I also certify that I have the authority to carry out the proposed activities, and I agree to start work only after I have received all necessary permits. I hereby authorize the agent named in Part 3 of this application to act on my behalf in matters related to this application. ___KT______ (initial) By initialing here, I state that I have the authority to grant access to the property. I also give my consent to the permitting agencies entering the property where the project is located to inspect the project site or any work related to the project. ___KT______ (initial) Kim Truong 2/16/2023 Applicant Printed Name Applicant Signature Date 11b. Authorized Agent Signature [help] I certify that to the best of my knowledge and belief, the information provided in this application is true, complete, and accurate. I also certify that I have the authority to carry out the proposed activities and I agree to start work only after all necessary permits have been issued. Authorized Agent Printed Name Authorized Agent Signature Date 11c. Property Owner Signature (if not applicant) [help] Not required if project is on existing rights-of-way or easements (provide copy of easement with JARPA). I consent to the permitting agencies entering the property where the project is located to inspect the project site or any work. These inspections shall occur at reasonable times and, if practical, with prior notice to the landowner. Property Owner Printed Name Property Owner Signature Date 18 U.S.C §1001 provides that: Whoever, in any manner within the jurisdiction of any department or agency of the United States knowingly falsifies, conceals, or covers up by any trick, scheme, or device a material fact or makes any false, fictitious, or fraudulent statements or representations or makes or uses any false writing or document knowing same to contain any false, fictitious, or fraudulent statement or entry, shall be fined not more than $10,000 or imprisoned not more than 5 years or both. If you require this document in another format, contact the Governor’s Office for Regulatory Innovation and Assistance (ORIA) at (800) 917-0043. People with hearing loss can call 711 for Washington Relay Service. People with a speech disability can call (877) 833- 6341. ORIA publication number: ORIA-16-011 rev. 09/2018 44 of 347 JARPA Attachment C Rev. 10/2016 Page 1 of 1 WASHINGTON STATE Joint Aquatic Resources Permit Application (JARPA) [help] Attachment C: Contact information for adjoining property owners. [help] Use this attachment only if you have more than four adjoining property owners. Use black or blue ink to enter answers in white spaces below. 1.Contact information for all adjoining property owners. [help] Name Mailing Address Tax Parcel # (if known) Roberta and John French 10214 SE 320th St 3339400622 Auburn, WA 98092 Julia and Darrell Wallis 10250 31st Ave SW 3339400660 Seattle, WA 98146 Colleen K and Zachery K Murphy 21 John Wayne Ln 3339400655 Aberdeen, WA 98520 Su Webb and David Goertzen 10399 SE 318th St 3339400636 Auburn, WA 98092 Jalene and Darrell King 31873 104th AVE SE 3339400633 Auburn, WA 98092 If you require this document in another format, contact the Governor’s Office for Regulatory Innovation and Assistance (ORIA) at (800) 917-0043. People with hearing loss can call 711 for Washington Relay Service. People with a speech disability can call (877) 833-6341. ORIA publication number: ORIA-16-014 rev. 10/2016 AGENCY USE ONLY Date received: Agency reference #: Tax Parcel #(s): TO BE COMPLETED BY APPLICANT [help] Project Name: Location Name (if applicable): 45 of 347 46 of 347 47 of 347 48 of 347 49 of 347 50 of 347 51 of 347 SCALE: 1" = 30' SITE PLAN SCALE IN FEET 0 30 601530 (1" = 30')N 52 of 347 SCALE: 1" = 30' SITE PLAN SCALE IN FEET 0 30 601530 (1" = 30')N 53 of 347 Supplemental Name: SHL Written Statement The Shoreline Designation according to the Shoreline Master Program. Urban Conservancy The name of the shoreline (Green or White River) that the site of the proposal is associated with. Green River A specific description of the proposed project, including the proposed use(s) and the activities necessary to accomplish the project. Overall project: The Garden Avenue Realignment project will create a new east/west connection between Garden Avenue and 104th Ave SE, and will replace the existing Garden Avenue connection to 8th Street NE with a permanent cul-de-sac and a new half street improvement from the cul-de-sac to the new roadway. The project will have a right-of-way acquisition phase, which includes acquisition from 2 parcels (#3339400660 and #3339400655) adjacent to the proposed new roadway alignment. The following utility improvements are anticipated: •Storm improvements necessary to support the roadway surfaces. •Install 2 new parallel water mains and replace the 6” water line with 8” water main along Garden Avenue from 8th Street NE to the new east/west roadway for the future Lea Hill pump station. •Extend the existing sewer line in the new east/west roadway from the existing manhole to Garden Avenue and provide side sewer stub to the properties to the north and south of the new sewer line. Area of Shoreline jurisdiction: The 200ft. buffer consists of the following: - Replace the existing Garden Avenue connection to 8th Street NE with a permanent cul-de-sac and a new half street improvement along the east side of the road from the cul-de-sac to the new roadway. •Install 2 new parallel water mains and replace the 6” water line with 8” water main along Garden Avenue from 8th Street NE to the new east/west roadway for the future Lea Hill pump station. - Re-grading and plant mitigation in the area where imperious surfaces were removed. A general description of the property’s existing physical characteristics, improvements, and structures. This is a developed urban area with roadways, above and underground utilties, and residential homes. A general description of adjacent (within 1,000 feet in all directions) uses, structures, improvements, intensity of development, and physical characteristics. Properties adjacent to the project site is urban residential with developed roadway, above and underground utilities, and residential homes. There is also a park nearby. Jurisdiction:Auburn Project Name: Garden Avenue Realignment Application ID: 1216312 54 of 347 EXHIBIT 4 ENG-158, Revised 9/18 Memorandum To: Alexandria Teague, Senior Planner From: Kim Truong, Project Engineer Date: 2/14/2023 Re: CP2022, Garden Ave Realignment Shoreline Substantial Development Permit This memo supplements the Shoreline Substantial Development Permit Application submitted for CP2022, Garden Ave Realignment Project (“the project”). The purpose of this memo is to explain how the project is consistent with the policies and provisions of the Shoreline Master Plan (SMP - adopted by ECY May 7, 2020). The policy and provisions of the SMP are in italics below and the explanations are in standard (non- italic) font. The project proposed is within “Urban Conservancy” shoreline environment. SMP 3.3.3 Urban Conservancy – Management Policies: SMP 3.3.3(1). Primary allowed uses and their associated development standards should preserve the natural character of the area or promote preservation of open space, floodplain or sensitive lands where they exist in urban and developed settings, either directly or over the long term. Uses that result in restoration of ecological functions should be allowed if the use is otherwise compatible with the purpose of the environment and the setting. This project site is fully developed consists mainly of existing roadway, compacted gravel shoulders and driveways, and vacant lots that are covered in compacted gravel and grass groundcover. The project proposes to reconfigure and reconstruct a portion of the existing roadway to include a cul-de-sac, sidewalk, and underground water piping replacement. More than half of the existing impervious area within the 100ft buffer will be located farther away from the river as a result of this project. Also, approximately 2,500sf area of native planting within the 100ft buffer is proposed as part of this project. The functionality of the area within the 200ft shoreline buffer will remain the same with added planting area. 55 of 347 EXHIBIT 5 ENG-158, Revised 9/18 SMP 3.3.3(2). Standards should be established for shoreline stabilization measures, vegetation conservation, water quality, and shoreline modifications within the "urban conservancy" designation. These standards should ensure that new development does not result in a net loss of shoreline ecological functions or further degrade other shoreline values. This project site is fully developed. This project will not alternate the use or functionality of the area within the shoreline buffer. In addition, a 2,500sf of planting area will be added to support the shoreline ecological functions. The new roadway surface will be graded to drain to an onsite bioswale/rain garden where stormwater will infiltrate and recharge the groundwater. SMP 3.3.3(3). Public access and public recreation objectives should be implemented whenever feasible and significant ecological impacts can be mitigated. This project aligns with this objective by providing new sidewalk improving the pedestrian access within the neighborhood. SMP 3.3.3(4). Water-oriented uses should be given priority over nonwater- oriented uses. For shoreline areas with commercial development or adjacent to commercially navigable waters, water-dependent uses should be given highest priority. The project will not preclude, replace, or otherwise adversely impact water-oriented uses. There will be no work to be done within the navigable waters. SMP 3.3.3(5). Existing mining and related activities may be an appropriate use within the urban conservancy environment when conducted in a manner consistent with the environment policies and provisions of WAC 173-26-241(3)(h) and when located consistent with mineral resource lands designation criteria pursuant to RCW 36.70A.170 and WAC 365-190-070. No new mining uses or expansion of existing mines should be permitted within the shoreline jurisdiction. Not applicable. The project is not a mining related activity. 56 of 347 ENG-158, Revised 9/18 Memorandum To: Alexandria Teague, Senior Planner From: Kim Truong, Project Engineer Date: 1/24/2023 Re: CP2022, Garden Ave Realignment Shoreline Substantial Development Permit This memo supplements the Critical Area Determination Application submitted for CP2022, Garden Ave Realignment Project (“the project”). The purpose of this memo is to document the critical areas exemption based on the following exception criteria of ACC 16.10.040 below. The exception criteria are in italics and the explanations are in standard (non-italic) font. 4. Minor Utility and Street Projects. Utility or street projects which have minor or short duration impacts to critical areas, as determined by the director in accordance with the criteria below, and which do not significantly impact the functions or values of a critical area(s); provided, that such projects are constructed with best management practices and additional restoration measures are provided. Minor activities shall not result in the transport of sediment or increased storm water. Such allowed minor utility projects shall meet the following criteria: a. There is no practical alternative to the proposed activity with less impact on critical areas; The project proposes to remove the direct vehicular access to and from Garden Ave and SE 320th St/8th St NE for operational and safety reasons by adding a cul- de-sac at the end of Garden Ave. The cul-de-sac is designed to the minimum size requirement of the City of Auburn Design Standards. This improvement does not significantly impact the functions or values of the critical area. b. The activity involves the placement of underground piping, conduit, traffic signal equipment, lighting equipment, utility pole(s), signs, anchor, or vault or other small component of a utility or street facility; The project limit that is within the 100ft buffer mainly consists of existing roadway, compacted gravel shoulders and driveways, and a vacant lot that’s half 57 of 347 EXHIBIT 6 ENG-158, Revised 9/18 covered in compacted gravel. The project proposes to reconfigure and reconstruct a portion the existing roadway to include a cul-de-sac and underground water piping. See attached site plan. More than half of the existing impervious area will be located farther away from the river as a result of the project. Also, approximately 2,500sf area of native planting within the 100ft buffer is proposed as part of the project. 58 of 347 59 of 347EXHIBIT 7 60 of 347 61 of 347 62 of 347 63 of 347 64 of 347 Garden Ave. Realignment Stormwater Site Plan CITY OF AUBURN PREPARED BY: MURRAYSMITH, INC. 600 UNIVERSITY STREET, SUITE #300 SEATTLE, WA 98101 www.murraysmith.us March 2023 PREPARED BY: CONSOR, INC. 600 UNIVERSITY STREET, SUITE #300 SEATTLE, WA 98101 www.consoreng.com 65 of 347 EXHIBIT 8 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page i Table of Contents Chapter 1 Project Overview 1.1. Introduction......................................................................................................................................1-1 1.2. Scope of Work..................................................................................................................................1-1 1.3. Project Location................................................................................................................................1-1 1.4. Major Site Constraints......................................................................................................................1-2 1.5. Required Permits and Approvals......................................................................................................1-2 Chapter 2 Existing Conditions 2.1. Land Use, Zoning, and Ground Cover..............................................................................................2-1 2.2. Geotechnical Information................................................................................................................2-1 2.2.1. Soils Inventory.........................................................................................................................2-1 2.2.2. Groundwater...........................................................................................................................2-1 2.2.3. Infiltration Rates.....................................................................................................................2-2 2.3. Existing Infrastructure......................................................................................................................2-2 2.3.1. Drainage..................................................................................................................................2-2 2.3.2. Other Utilities..........................................................................................................................2-2 Chapter 3 Off-Site Analysis 3.1. Introduction......................................................................................................................................3-1 3.2. Qualitative Analysis..........................................................................................................................3-1 Chapter 4 Permanent Stormwater Control Plan 4.1. Threshold Discharge Areas...............................................................................................................4-1 4.2. Stormwater Modeling Methodology...............................................................................................4-1 4.3. Pre-Developed Site Hydrology.........................................................................................................4-2 4.4. Developed Site..................................................................................................................................4-2 4.4.1. Project Summary.....................................................................................................................4-2 4.4.2. Developed Site Hydrology.......................................................................................................4-2 4.4.3. On-Site Stormwater Management – Minimum Requirement #5 ..........................................4-3 4.4.4. Water Quality System – Minimum Requirement #6..............................................................4-6 4.4.5. Flow Control System – Minimum Requirement #7.................................................................4-6 4.4.6. Conventional Conveyance System Analysis and Design.........................................................4-6 66 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page ii Chapter 5 Minimum Requirements Review 5.1. Applicable Minimum Requirements................................................................................................5-1 5.1.1. Minimum Requirement #1 – Preparation of Stormwater Site Plan.......................................5-1 5.1.2. Minimum Requirement #2 – Construction Stormwater Pollution Prevention Plan...............5-1 5.1.3. Minimum Requirement #3 – Source Control of Pollution ......................................................5-1 5.1.4. Minimum Requirement #4 – Preservation of Natural Drainage Systems and Outfalls.........5-2 5.1.5. Minimum Requirement #5 – On-Site Stormwater Management ..........................................5-2 5.1.6. Minimum Requirement #6 – Runoff Treatment.....................................................................5-2 5.1.7. Minimum Requirement #7 – Flow Control.............................................................................5-2 5.1.8. Minimum Requirement #8 – Wetlands Protection ................................................................5-2 5.1.9. Minimum Requirement #9 – Operation and Maintenance....................................................5-2 5.1.10. Minimum Requirement #10 – Off-Site Analysis and Mitigation..........................................5-2 Figures Figure 1-1: Project Map...........................................................................................................................1-2 Tables Table 1-1: Project Permit Information....................................................................................................1-3 Table 2-1: Recommended Preliminary Infiltration Rates by Depth .......................................................2-2 Table 4-1: Threshold Discharge Area Parameters..................................................................................4-1 Table 4-2: WWHM Input Parameters .....................................................................................................4-2 Table 4-3: Bioretention Area Comparison..............................................................................................4-5 67 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 1-1 CHAPTER 1 Project Overview 1.1 Introduction The City of Auburn (City) will construct road improvements located directly east of the Green River near the 8th Street NE bridge. The planned improvements include roadway expansion, roadway resurfacing, and a cul-de-sac, with added pervious pavement sidewalks. Due to the added impervious area, a drainage review is required to meet City stormwater management requirements. The project is officially titled: CP2022 – Garden Avenue Realignment Project. 1.2 Scope of Work Consor North America, Inc. (previously Murraysmith) was contracted to develop this Stormwater Site Plan (SSP) report to document recommendations for best management practices (BMPs) to manage stormwater from the roadway improvements. 1.3 Project Location The project location is in the north-central part of the City of Auburn, Washington. The project site is bordered by the Green River to the west, SE 320th Street to the south, 104th Avenue SE to the east, and SE 318th Street to the north. The project includes modifications to 104th Avenue SE, SE 318th Street, and Garden Avenue. Figure 1-1 shows the extents of the project site. Construction will occur within the City Right-of-Way (ROW), on a City-owned parcel, and on an easement located on 25 W Main St., Auburn, Washington. The full project area is located within Township T.21N Range R5.E, Section 8. 21-3259 68 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 1-2 Figure 1-1: Project Map1 1.4 Major Site Constraints With its proximity to the Green River, the project site is within a Riparian Habitat Zone. The project is located within the City of Auburn Zone 2 for groundwater protection. All stormwater management practices and facilities must adhere to groundwater and habitat protections in place for these designated zones. 1.5 Required Permits and Approvals Since the project is within a groundwater protection zone, additional approval from the City of Auburn Engineer is required to proceed with construction of an infiltrating bioretention facility. An infiltration trench was recently constructed within the project area, therefore obtaining similar approval with proper design of the stormwater BMPs appears consistent with the City’s previous improvements. Table 1-1 summarizes the relevant permit information. 1 Google Maps, City of Auburn intersection of SE 320th St and 104th Ave SE, 16 March 2023 21-3259 69 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 1-3 Table 1-1: Project Permit Information Permit Type Floodplain Permit – # FDP22-0009 Critical Areas Permit – # CAO22-0010 SEPA Permit – # SEP22-0021 Shoreline Permit – # SHL22-0001 Site Address SE 318th Street and Garden Avenue Legal Description Township T.21N Range R5.E, Section 8 Situate in the County of King, State of Washington Parcel Numbers Public Right-of-Way Watershed Duwamish – Green River 21-3259 70 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 2-1 CHAPTER 2 Existing Conditions 2.1 Land Use, Zoning, and Ground Cover The project site is located within the City of Auburn urban growth area (UGA). The land use is designated for single family homes and is zoned as R1 Residential (one dwelling unit per acre). The project is located within the ROW and within City-owned parcels. The project site is relatively level with minimal grade change throughout. The local foliage includes grasses, blackberry bushes, thin alders and maples, and short brush. The widened street sections and sidewalk will be constructed in areas that are currently covered with short grasses and gravel. Appendix G shows where the proposed roadway will replace grassy areas (new impervious area) or gravel (replaced impervious area). There is one medium sized pear tree within the project area that will likely need to be removed (approximate station 13+25). With its proximity to the Green River, the project site is also within a Riparian Habitat Zone. A map with the Riparian Habitat Zone delineations is included in Appendix E. The project is outside of the Federal Emergency Management Agency (FEMA) 100-year flood hazard zone boundary, per the City of Auburn Flood Plain Map included in Appendix E. Due to nearby groundwater wells, the project site is within the Zone 2 groundwater protection area. The requirements associated with stormwater projects within the groundwater protection area are discussed further in Chapter 4.4.3 of this report. 2.2 Geotechnical Information Boring logs were completed for another project on a parcel adjacent to SE 318th Street. The boring logs have been utilized as the basis of design for this project due to the proximity to the project site and as a cost saving approach for the City. There are five test pits, four grain size analyses, and two cation exchange capacity tests. See the attached logs in Appendix D for test pit location maps and related data. 2.2.1 Soils Inventory According to the National Resources Conservation Service (NRCS) web soil survey, the project site soils consist of both Orida silt loam and urban land. Orida silt loam is an alluvial flood plain deposit, and urban land designates soils that have been modified by human activities. The NRCS data was corroborated by the historical boring logs in the area. The NRCS report for the project area may be found in Appendix D. 2.2.2 Groundwater During the historical borings groundwater was noted at depths ranging from 8.5-feet to 11-feet below existing grade. The groundwater depth was generally observed to be greater toward the west side of the project site. The boring logs were completed May. Wet season groundwater should be accounted for by adding an additional foot to the measured groundwater, meaning that the maximum high groundwater levels can be approximated at about 7.5 to 10-feet below existing grade. 21-3259 71 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 2-2 2.2.3 Infiltration Rates Geotechnical explorations found native alluvial soils near surface elevations which have moderate permeability. At greater depths, the soils become a sandy gravel which has a rapid infiltration rate. Fine sand and silt were found between the two distinct soil stratums. The historical boring logs and grain size analyses were used to calculate recommended infiltration rates; results are summarized in Table 2-1 and the supporting calculations are included in Appendix D. The average of depths across test pits was used as the historical borings indicate limited variation of soil layer depths, which leads to the conclusion that the area surrounding the site has limited variation of soil layer depths. The current Ecology manual requires an infiltration test or grain size analysis be conducted at the location of the proposed infiltration facility; however, Washington State Department of Ecology does allow use of nearby data so long as there is limited soil variation within the project area. The conclusion of limited variation of soil layer depths in the surrounding area of the project site allows the grain size analysis to be completed using data from the near- by borings. Table 2-1: Recommended Infiltration Rates by Depth Recommended Infiltration Rate (Inches/Hour) Depth Range (Feet Below Ground Surface) 22 1- to 5.5-ft 282 5.5- to 10-ft 2.3 Existing Infrastructure 2.3.1 Drainage Because the site is relatively flat, there is negligible run-on to the street from adjacent properties. Under current conditions, stormwater within the vicinity of the project site dissipates through dispersion over the grassy areas. There are ditches along the east side of 104th Ave that convey stormwater to a municipal storm drain. During the construction of recent improvements on SE 318th, an infiltration trench was constructed along the south side of the same roadway. It is proposed to remove that trench and divert flows to a new stormwater facility as part of this project. No historical drainage, flooding, or erosion problems in this area were reported to the project team. There are no visual signs on the landscape that indicate long term drainage issues. 2.3.2 Other Utilities Underground sanitary sewer, water, and gas utilities exist in the area. Most of the planned excavation will occur within the footprint of the proposed bioretention facility, which appears vacant of existing underground utilities. There are no known fuel tanks, groundwater wells, or septic systems within 100-feet of the project site. 21-3259 72 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 3-1 CHAPTER 3 Off-Site Analysis 3.1 Introduction Off-site analysis is the City’s Minimum Requirement #10. All development projects which trigger Minimum Requirements #1 through #5 or #1 through #9 must address Minimum Requirement #10. Projects which discharge stormwater off-site must assess the potential off-site impacts of stormwater discharge. A qualitative analysis including upstream systems entering the site (run-on) and downstream systems leaving the site (run-off) is required for all sites. The City may require a quantitative analysis for any project deemed to need additional downstream information. No quantitative analysis has been required for this project. 3.2 Qualitative Analysis Based on existing topography, land cover, and soil types there is little likelihood of run-on from offsite properties and no account of run-on is necessary for the stormwater analysis. All runoff is proposed to be infiltrated for enhanced treatment; thus, no off-site downstream analysis is required. 21-3259 73 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 4-1 CHAPTER 4 Permanent Stormwater Control Plan 4.1 Threshold Discharge Areas Current topography of the project site slopes generally from southwest to northeast. New and replaced impervious roadway surfaces will be graded such that run-off from these areas will sheet flow to the bioretention area on SE 318th Street without the use of drainage conveyance piping. This assumption results in a single Threshold Discharge Area (TDA). Sidewalks, which are proposed to be permeable, will not contribute to the TDA and therefore are not included in area calculations. Project areas were measured from design drawings; the delineations are presented in Appendix G and summarized in Table 4-1. Table 4-1: Threshold Discharge Area Parameters Description On-Site Area Existing Conditions Total TDA Area 49,400 Existing Impervious Surface 22,100 Existing Lawn/Landscaped Area 17,300 WWHM Pre-Developed Pervious Area**34,456 Proposed Conditions Total TDA Area 49,400 New Pollution Generating Hard Surface (PGHS)11,200 Replaced PGHS 22,100 New Plus Replaced PGHS**33,300 Proposed Bioretention Area**1,203 Land Disturbed 49,400 **Values are utilized in the WWHM stormwater modeling. 4.2 Stormwater Modeling Methodology In accordance with the WWSWM, the BMP facilities were sized using the Western Washington Hydrology Model (WWHM) 2012 version. The model inputs for the pre- and post-developed conditions are discussed in the following chapters. The model was analyzed for eight percent of the 2-year storm through the 50- year storm event. Table 4-2 summarizes the input parameters used in the WWHM model. The WWHM2012 pre-development and post-development model results are provided in Appendix C. Overall model results are discussed in later in this chapter. 21-3259 74 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 4-2 Table 4-2: WWHM Input Parameters Description Input Value WWHM Pre-Developed Pervious Area 34,456 sf (0.791 acres) New Plus Replaced PGHS 33,300 sf (0.763 acres) Proposed Bioretention Bottom Dimensions 150.38-feet long x 8-ft wide Proposed Bioretention Bottom Area 1,203 sf (0.028 acres) Enhanced Treatment Media Depth 1.5-ft Enhanced Treatment Media Infiltration Rate 12-inches/hour Native Soil Infiltration Rate 22-inches/hour 4.3 Pre-Developed Site Hydrology Runoff from the project site in pre-developed conditions would fully infiltrate into the native soils during the modeled storm events. The assumed WWHM inputs for the pre-developed site were flat, forested area. It is assumed that all pre-developed runoff will infiltrate via dispersion. Because the site is relatively flat and soils have high permeability, there is no run-on from off-site. 4.4 Developed Site 4.4.1 Project Summary The proposed road improvements include 0.763-acres of new or replaced impervious area, 0.214-acres of pervious sidewalk, and 0.028-acres that may be set aside for the stormwater facilities or landscaping. Utilizing the WWSWMM decision flow charts, bioretention was selected as the proposed BMP for this project site. The flow chart paths are attached as Appendix H. It is assumed that the new and replaced impervious roadway are graded such that stormwater from all areas will sheet flow to the proposed bioretention area on the north side of SE 318th Street. Sidewalks associated with the road improvements, constructed with permeable pavement, will contribute no additional flow to the bioretention area. 4.4.2 Developed Site Hydrology The new and replaced road areas were input as flat roads into the WWHM model. The bioretention area was included as saturated lawn. The sidewalks were not included in the model; it was assumed that rainfall will infiltrate directly through the pervious sidewalk, therefore the bioretention areas would not be affected by the sidewalks. There is assumed to be no run-on from any off-site sub-basins. The bioretention facility was input into the model with no underdrain; it is designed to fully infiltrate all runoff through the 50-year storm event. The facility is designed to include 18-inches of bioretention mix with an infiltration rate of 12-inches per hour in accordance with the standard bioretention design for Western Washington. An additional 6-inches of gravel is included at the bottom of the planter to facilitate infiltration. As discussed in Chapter 2 and Appendix D, there are two possible native infiltration rates. The model was run with both, to determine the appropriate depth of excavation for the bioretention facility. When the native infiltration rate of 22-inches per hour was utilized, no additional sand was placed between the 21-3259 75 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 4-3 bioretention soil mix and the gravel. When the native infiltration rate of 282-inches per hour was utilized, 30-inches of sand were included between the bioretention soil mix and the gravel to account for the extra excavation required to reach the native soils with that infiltration rate. The WWHM2012 Project reports are attached as Appendix C of this report. 4.4.3 On-Site Stormwater Management – Minimum Requirement #5 Stormwater BMPs for this project site were selected to meet the minimum requirements for treatment and flow control as described in the WWSWMM. Permeable pavement was selected as the BMP for the new sidewalks, and a bioretention facility was designed to treat the runoff from the new and improved road surfaces. The project site does not have connectivity to local storm drains. The historical borings show well-draining soils with anticipated good infiltration rates within the area, therefore, infiltration was selected as the primary method of flow control. The LID performance standard was the selected approach for stormwater design as opposed to the list approach. This is an acceptable approach for any project within the UGA. The LID performance standard is discussed further below. Since the project site is within the Zone 2 Groundwater Protection Area, Enhanced Treatment is required to protect the local groundwater aquifers from stormwater pollutants. Enhanced Treatment BMPs, per 2019 WWSWMM, include infiltration through soils that meet the criteria for run-off treatment per Site Suitability Criteria (SSC). The following chapter addresses each SSC criterium. 4.4.3.1 Site Suitability Criteria for Infiltration as Enhanced Treatment To ensure that infiltration is an acceptable Enhanced Treatment BMP approach, eight SSCs must be met. Each criterium is described in the following sub-sections. 4.4.3.1.1 SSC-1: Setback Criteria The project is partially located within the 10-year time of travel aquifer recharge area, as identified in Appendix E. Infiltration BMPs must therefore meet the Washington State Department of Health (WSDOH) requirements with respect to high-risk operations or facilities. No high-risk operations or facilities have been identified within the project runoff area; no additional steps to reduce contaminant loading are required. The biofiltration facilities must be located at least 20-feet downslope and 100-feet upslope of building foundations. The closest property foundations to the biofiltration facility are slightly upslope of the proposed bioretention facility location, and more than 20-feet away. The project site is naturally very flat; additional setback criteria for steep slopes do not apply. 4.4.3.1.2 SSC-2: Groundwater Protection Areas The project site is within the City of Auburn’s Zone 2 groundwater protection area, per maps provided in Appendix E. Infiltration BMPs are allowed with city engineer approval and use of enhanced treatment. 4.4.3.1.3 SSC-3: High Vehicle Traffic Areas The project site is not considered a high vehicle traffic area, therefore oil control BMPs are not required. 21-3259 76 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 4-4 4.4.3.1.4 SSC-4: Soil Infiltration Rate / Drawdown Time The measured (initial) soil infiltration rate should be 9-inches/hour or less for biofiltration facilities used for runoff treatment purposes. Initial infiltration rates for permeable pavements should be 12-inches/hour or less. This rate ensures adequate contact time between the stormwater runoff and the soils for treatment. For infiltration BMPs designed to provide runoff treatment, the water quality design volume must infiltrate through the infiltration BMP surface within 48-hours. 4.4.3.1.5 SSC-5: Depth to Bedrock, Water Table, or Impermeable Layer This criterion applies to infiltration basins and infiltration trenches, which are not proposed for this project site. 4.4.3.1.6 SSC-6: Soil Physical and Chemical Suitability for Treatment All runoff from pollutant generating sources shall be directed toward the bioretention facility. A bioretention media will be utilized in place of native soils to meet the treatment criteria which include cation exchange capacity and minimum organic content. Depth of soils used for infiltration treatment must be at least 18-inches within the biofiltration facility. The minimum cation exchange capacity (CEC) of treatment soils is 5 milliequivalents CEC per 100 grams of dry soil (meq/100g). Results from the geotechnical study of nearby native soils found a minimum CEC of 11.2 meq/100g at the project site, which exceeds this minimum requirement. The bioretention media will have a minimum of 1.0-percent organic content to increase the absorption capacity of the soil for pollutants. The organic content of the native soils was not measured during the geotechnical analysis. 4.4.3.1.7 SSC-7: Seepage Analysis and Control The proposed biofiltration area is not within any known seepage zones for nearby building foundations, basements, and roads. 4.4.3.1.8 SSC-8: Cold Climate and Impact of Roadway Deicers Deicers on the roadways could cause a violation of groundwater quality standards. It is recommended that the City of Auburn does not use deicers on the roadway sections which drain to biofiltration to project the facilities. 4.4.3.2 Permeable Sidewalks There are approximately 10,000 square feet of new sidewalk being proposed for this project site. Permeable pavement has been selected as the BMP for the sidewalk areas. By utilizing a permeable concrete, rainfall can permeate directly into the native soils. The concrete provides some pretreatment by removing trash and some sediments from the runoff before it is infiltrated. Because sidewalks are a non- pollutant-generating surface type, additional treatment of runoff that falls onto the sidewalks is not required. The permeable sidewalks therefore meet the treatment and flow control requirements for the new sidewalk construction. 21-3259 77 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 4-5 4.4.3.3 Bioretention Facility Runoff at this project site from pollutant-generating sources such as roadways require enhanced treatment due to the proximity to local Groundwater Protection Zone 2. In accordance with the WWSWMM, bioretention facilities meet enhanced treatment requirements by treating runoff with a specified bioretention media. Bioretention was therefore selected as the primary runoff mitigation technique for the pollution-generating road surfaces at this project site. 4.4.3.4 LID Performance Standard To meet the performance standard for both treatment and flow control, stormwater discharges must match developed discharge durations for the range of pre-developed discharge rates from eight percent of the 2-year peak flow through the full 50-year flow. Bioretention is an acceptable BMP to achieve the LID performance standard. The bioretention facility has been designed to fully infiltrate through the 50-year storm. Projects which choose the LID performance standard must also apply BMP T5.13. The post-construction soil quality and depth standards, as described in the WWSWMM, must be met for the biofiltration facilities and any additional landscaped areas. Native duff and topsoil will be retained to the maximum extent practicable, properly stockpiled for reapplication when necessary; compost and other materials will be used to meet organic matter content requirements, neutral or native pH, and appropriate carbon to nitrogen ratios; and once established, important soil depths will be protected from compaction and erosion. The biofiltration soil mix and facility design will meet the soil quality and depth requirements. A typical bioretention planter facility design example is attached as Appendix F. 4.4.3.5 Alternative Analysis The historical borings, discussed in Chapter 2 and attached as Appendix D, identified two native soil layers which could influence the bioretention infiltration rate. Two alternative designs have been identified utilizing the two infiltration rates. Alternative A assumes a standard depth bioretention facility, which will be bound by the shallower native infiltration rate of 22-inches per hour. Alternative B assumes a deeper excavation to reach the higher infiltration rate of 282-inches per hour. However, without a geotechnical boring within the exact footprint of the proposed bioretention facility, designing for the high infiltration rate presented in Alternative B presents risks. Modeling to size the bioretention facility was run with both infiltrations rates, as summarized below in Table 4-3. However, we recommend assuming the infiltration identified in Alternative A, while constructing the bioretention facility to the required depths of Alternative B to provide adequate safety factor to achieve the desired facility performance. Table 4-3: Bioretention Area Comparison Parameter Alternative A Alternative B Infiltration Rate 22 inches/hour 282 inches/hour Model Bioretention Area Output 1,203 square feet 900 square feet The main differences between the two alternatives are the bioretention area needed to meet enhanced treatment and LID performance standards, and excavation depth required to install the bioretention areas. Although the bioretention facility is sized to infiltrate the full water quality design volume, a back-up drainage system should be provided in case the bioretention facility is overwhelmed to prevent localized flooding (i.e., for scenarios where storm events exceed the 50-year storm). An overflow beehive grate can 21-3259 78 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 4-6 be added to route bioretention overflow to an underdrain which discharges to the existing stormwater drainage ditch along 104th Avenue SE. To meet the requirements of the WWSWMM, the overflow should be designed to receive only flows above the 50-year runoff event or receive flows that have passed through the bioretention media and been treated. 4.4.3.6 Facility Ownership and Maintenance The proposed stormwater facilities shall be within the City-owned right-of-way and shall therefore be the responsibility of the City Public Works department. Additional information on operations and maintenance procedures and protocol may be found in Appendix A. 4.4.4 Water Quality System – Minimum Requirement #6 Water quality standards can be met by utilizing the proper soil mix in the bioretention area. This has been addressed in the design concerns for the bioretention; therefore, Minimum Requirement #6 is met through Minimum Requirement #5. 4.4.5 Flow Control System – Minimum Requirement #7 Flow control standards can be met with infiltration, which causes no off-site discharge. The bioretention area sized for Minimum Requirement #5 is intended to collect and infiltrate all impervious area site runoff, thereby meeting Minimum Requirement #7 as well. 4.4.6 Conventional Conveyance System Analysis and Design The project site does not have good connectivity to local storm drains. No conventional conveyance system is proposed, analyzed, or designed. 21-3259 79 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 5-1 CHAPTER 5 Minimum Requirements Review 5.1 Applicable Minimum Requirements The project site existing surfaces are currently less than 35 percent impervious; therefore, the project is considered a new development under the Department of Ecology’s (Ecology) Stormwater Management Manual for Western Washington (SMMWW). Minimum Requirements #1 through #9 apply to new development projects which result in 5,000 square feet, or more, of new hard surfaces. The project results in 12,700 square feet of new hard surfaces; Minimum Requirements #1 through #9 apply to all new and replaced hard surfaces and converted vegetation areas. Per the City’s Supplemental Manual, all projects triggering Minimum Requirements #1 through #9 are also required to meet Minimum Requirement #10 – Off-Site Analysis and Mitigation. Each of the ten requirements are discussed in more detail in the sub- sections below. 5.1.1 Minimum Requirement #1 – Preparation of Stormwater Site Plan All projects must prepare a stormwater site plan (SSP) to address applicable Minimum Requirements and justify non-applicable Minimum Requirements. This report satisfies Minimum Requirement #1. 5.1.2 Minimum Requirement #2 – Construction Stormwater Pollution Prevention Plan Projects adding or replacing 5,000 square feet, or more, of hard surface must prepare a complete Construction Stormwater Pollution Prevention Plan (SWPPP). Best management practices (BMPs) must be chosen to address each of the thirteen elements, unless site conditions render the element unnecessary, and exemption is clearly justified. The thirteen elements are: preserve vegetation and mark clearing limits, establish construction access, control flow rates, install sediment controls, stabilize soils, protect slopes, protect drain inlets, stabilize channels and outlets, control pollutants, control de-watering, maintain BMPs, manage the project, and protect low impact development (LID) BMPs. Each of these elements, their applicability to the project, and recommended BMPs are discussed in more detail in the SWPPP, attached as Appendix B. 5.1.3 Minimum Requirement #3 – Source Control of Pollution All known, available, and reasonable source control BMPs are required for all projects. Source control BMPs include operational BMPs and structural source control BMPs. The site does not have any existing known or suspected pollutants of concern. Source control will be limited to standard roadway and construction BMPs. Construction source control is part of the SWPPP, attached as Appendix B. Permanent source control is included with the Operations and Maintenance Manual, attached as Appendix A. 21-3259 80 of 347 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 5-2 5.1.4 Minimum Requirement #4 – Preservation of Natural Drainage Systems and Outfalls Due to the flat nature and permeable soils of the site, there is little, if any surface runoff in existing conditions. The proposed improvements will result in the infiltration of all runoff within bioretention facilities, thereby preserving the natural drainage system. 5.1.5 Minimum Requirement #5 – On-site Stormwater Management Redevelopment projects within the UGA must follow low impact development (LID) performance standards and BMP T5.13 or List #2, as described in the WWSWMM. The project meets the LID performance standards through bioretention, and permeable pavement as discussed in Chapter 4, and documented with the WWHM2012 Project Report in Appendix C. All disturbed area without hard surface cover will be landscaped and soils will be amended per BMP T5.13. 5.1.6 Minimum Requirement #6 – Runoff Treatment Thresholds for runoff treatment will be assessed based upon all new and replaced pollution generating surfaces. The treatment threshold is 5,000 square feet, or more, total pollution generating hard surfaces. This project includes approximately 33,300 square feet of pollution generating hard surfaces. Additionally, this site is within the Zone 2 groundwater protection area, which requires Enhanced Treatment for runoff. Runoff treatment requirements will be met through bioretention and infiltration, as presented in Chapter 4 of this report. 5.1.7 Minimum Requirement #7 – Flow Control Runoff from all new impervious surfaces will be infiltrated resulting in less than 10,000 square feet of effective new impervious area. Full infiltration of runoff via Minimum Requirement #5 will effectively address flow control. No additional flow control measures are required. 5.1.8 Minimum Requirement #8 – Wetlands Protection There are no wetlands inventoried by the City on or in the vicinity of the site, and all runoff from new impervious surfaces will be captured, treated, and infiltrated. No additional wetlands protection measures are required. 5.1.9 Minimum Requirement #9 – Operation and Maintenance An Operation and Maintenance Manual is included with this report as Appendix A. 5.1.10 Minimum Requirement #10 – Off-Site Analysis and Mitigation All project runoff will infiltrate to meet previous Minimum Requirements; therefore, this project will cause no off-site discharge. No further off-site analysis is required. 21-3259 81 of 347 Appendix A Minimum Requirement Flow Chart 82 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 1 Operations and Maintenance Manual 1.1 Introduction The stormwater facilities at this project site will be maintained by the City of Auburn Public Works department (253-931-3048). The City will determine proper storage of this manual to facilitate continued maintenance. There are two types of facilities to be maintained on this project site, a bioretention facility and pervious pavement. The following sections describe the on-site stormwater management facilities and standard maintenance requirements for each. 1.2 Bioretention Facility The project site will contain 1,200 square feet of bioretention, in an 8-foot-wide strip along the northern edge of SE 318th Street. The site will be graded such that all stormwater from impervious surfaces on the site will sheet flow to the bioretention facility. The bioretention area will consist of three main layers: native soil base, special bioretention media, and topsoil with appropriate planting. Bioretention facilities require annual plant, soil, and mulch layer maintenance to maintain treatment and infiltration capabilities. It is recommended to maintain the facilities at least every 6 months and inspect them after all major rainfall events. Additional inspections may be required for the first few years after installation as the plants get established. The following items are included in the 2019 WWSWMM as typical maintenance procedures. See the maintenance tables at the end of this section for additional maintenance information. Watering: Plants should be selected to be drought tolerant and not require watering after establishment (2 to 3 years). Watering may be required during prolonged dry periods after plants are established. Erosion control: Inspect flow entrances, ponding area, and surface overflow areas periodically, and replace soil, plant material, and/or mulch layer in areas if erosion has occurred. Properly designed BMPs with appropriate flow velocities should not have erosion problems except perhaps in extreme events. If erosion problems occur, the following should be reassessed: (1) flow volumes from contributing areas and bioretention cell sizing; (2) flow velocities and gradients within the cell; and (3) flow dissipation and erosion protection strategies in the pretreatment area and flow entrance. If sediment is deposited in the bioretention area, immediately determine the source within the contributing area, stabilize, and remove excess surface deposits. 83 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 2 Sediment removal: Follow the maintenance plan schedule for visual inspection and remove sediment if the volume of the ponding area has been compromised. Plant material: Depending on aesthetic requirements, occasional pruning and removing dead plant material may be necessary. Replace all dead plants and if specific plants have a high mortality rate, assess the cause and replace with appropriate species. Periodic weeding is necessary until plants are established. Weeding: Invasive or nuisance plants should be removed regularly and not allowed to accumulate and exclude planted species. At a minimum, schedule weeding with inspections to coincide with important horticultural cycles (e.g., prior to major weed varieties dispersing seeds). Weeding should be done manually and without herbicide applications. The weeding schedule should become less frequent if the appropriate plant species and planting density are used and the selected plants grow to capture the site and exclude undesirable weeds. Nutrient and pesticides: The soil mix and plants are selected for optimum fertility, plant establishment, and growth. Nutrient and pesticide inputs should not be required and may degrade the pollutant processing capability of the bioretention area, as well as contribute pollutant loads to receiving waters. By design, bioretention BMPs are located in areas where phosphorous and nitrogen levels may be elevated and these should not be limiting nutrients. If in question, have soil analyzed for fertility. Mulch: Replace mulch annually in bioretention BMPs where heavy metal deposition is high (e.g., contributing areas that include gas stations, ports and roads with high traffic loads). In residential settings or other areas where metals or other pollutant loads are not anticipated to be high, replace or add mulch as needed (likely 3 to 5 years) to maintain a 2 to 3 inch depth. Soil: Soil mixes for bioretention BMPs are designed to maintain long-term fertility and pollutant processing capability. Estimates from metal attenuation research suggest that metal accumulation should not present an environmental concern for at least 20 years in bioretention systems, but this will vary according to pollutant load. Replacing mulch media in bioretention BMPs where heavy metal deposition is likely provides an additional level of protection for prolonged performance. If in question, have soil analyzed for fertility and pollutant levels. 1.3 Pervious Pavement The project site will contain approximately 10,000 square feet of new sidewalk. All sidewalk is proposed permeable pavement to reduce site runoff. Permeable concrete allows rainfall to permeate directly into the native soils, while providing some pretreatment through trash separation and some sediment capture. Pervious pavement should be maintained 1-2 times each year and maintained after major storm events. The following guidelines are included in the 2019 WWSWMM as maintenance recommendations for permeable pavements. Additional guidelines may be found at in the maintenance tables at the end of this document. 84 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 3 Erosion and introduction of sediment from surrounding land uses should be strictly controlled after construction by amending exposed soil with compost and mulch, planting exposed areas as soon as possible, and armoring outfall areas. Surrounding landscaped areas should be inspected regularly and possible sediment sources controlled immediately. Installations can be monitored for adequate or designed minimum infiltration rates by observing drainage immediately after heavier rainstorms for standing water or infiltration tests using ASTM C1701. Clean permeable pavement surfaces to maintain infiltration capacity at least once or twice annually following recommendations below. Utility cuts should be backfilled with the same aggregate base used under the permeable paving to allow continued conveyance of stormwater through the base, and to prevent migration of fines from the standard base aggregate to the more open graded permeable base material. Ice buildup on permeable pavement is reduced and the surface becomes free and clear more rapidly compared to conventional pavement. For western Washington, deicing and sand application may be reduced or eliminated, and the permeable pavement installation should be assessed during winter months and the winter traction program developed from those observations. Vacuum and sweeping frequency will likely be required more often if sand is applied. Clean surfaces using suction, sweeping with suction or high-pressure wash and suction (sweeping alone is minimally effective). Handheld pressure washers are effective for cleaning void spaces and appropriate for smaller areas such as sidewalks. For large scale cleaning use vacuum surface cleaning machines (such as Cyclone, Elgin, etc.) for cleaning pervious concrete and porous asphalt. Small utility cuts can be repaired with conventional asphalt or concrete if small batches of permeable material are not available or are too expensive. 1.4 Source Control BMPs The following source control BMPs are collected from several sections of the SWMMWW Source Control BMP Library, including: source control BMPs applicable to all sites; roads, ditches, and parking lot source controls BMPs; soil erosion, sediment control, and landscaping source control BMPs; and other source control BMPs. 1.4.1 S410 – Correcting Illicit Discharges to Storm Drains For all real properties, responsible parties must examine their plumbing systems to identify any potential illicit discharges. Review site plans, engineering drawings, or other sources of information for the plumbing systems on the property. 85 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 4 If an illicit discharge is suspected, trace the source using an appropriate method such as visual reconnaissance, smoke test, flow test, dye test with a nontoxic dye, or closed circuit television (CCTV) inspection. These tests are to be performed by qualified personnel such as a plumbing contractor. Note: Contact Ecology prior to performing a dye test which may result in a discharge to a receiving water. If illicit connections are found, permanently plug or disconnect the connections. Eliminate prohibited discharges to storm sewer, ground water, or surface water. Convey unpermitted discharges to a sanitary sewer if allowed by the local sewer authority, or to other approved treatment. Obtain all necessary permits for altering or repairing side sewers and plumbing fixtures. Restrictions on certain types of discharges, particularly industrial process waters, may require pretreatment of discharges before they enter the sanitary sewer. It is the responsibility of the property owner or business operator to obtain the necessary permits and to replace the connection. Obtain appropriate state and local permits for these discharges 1.4.2 S453 – Formation of a Pollution Prevention Team The pollution prevention team should be responsible for implementing and maintaining all BMPs and treatment for the site. This team should be able to address any corrective actions needed on site to mitigate potential stormwater contamination. The team members should: Consist of those people who are familiar with the facility and its operations. Possess the knowledge and skills to assess conditions and activities that could impact stormwater quality at your facility, and who can evaluate the effectiveness of control measures. Assign pollution prevention team staff to be on duty on a daily basis to cover applicable permittee facilities when those facilities are in operation. Have the primary responsibility for developing and overseeing facility activities necessary to comply with stormwater requirements. Have access to all applicable permit, monitoring, SWPPP, and other records. Be trained in the operation, maintenance and inspections of all BMPs and reporting procedures. Establish responsibilities for inspections, operation, maintenance, and emergencies. 86 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 5 Regularly meet to review overall facility operations and BMP effectiveness. 1.4.3 S454 – Preventative Maintenance and Good Housekeeping Prevent the discharge of unpermitted liquid or solid wastes, process wastewater, and sewage to ground or surface water, or to storm drains that discharge to surface water, or to the ground. Conduct all oily parts cleaning, steam cleaning, or pressure washing of equipment or containers inside a building, or on an impervious contained area, such as a concrete pad. Direct contaminated stormwater from such an area to a sanitary sewer where allowed by local sewer authority, or to other approved treatment. Promptly contain and clean up solid and liquid pollutant leaks and spills including oils, solvents, fuels, and dust from manufacturing operations on an exposed soil, vegetation, or paved area. If a contaminated surface must be pressure washed, collect the resulting washwater for proper disposal (usually involves plugging storm drains, or otherwise preventing discharge and pumping or vactoring up washwater, for discharge to sanitary sewer or for vactor truck transport to a waste water treatment plant for disposal). Do not hose down pollutants from any area to the ground, storm drains, conveyance ditches, or receiving water. Convey pollutants before discharge to a treatment system approved by the local jurisdiction. Sweep all appropriate surfaces with vacuum sweepers quarterly, or more frequently as needed, for the collection and disposal of dust and debris that could contaminate stormwater. Use mechanical sweepers, and manual sweeping as necessary to access areas that a vacuum sweeper can't reach to ensure that all surface contaminants are routinely removed. Do not pave over contaminated soil unless it has been determined that ground water has not been and will not be contaminated by the soil. Call Ecology for assistance. Construct impervious areas that are compatible with the materials handled. Portland cement concrete, asphalt, or equivalent material may be considered. Use drip pans to collect leaks and spills from industrial/commercial equipment such as cranes at ship/boat building and repair facilities, log stackers, industrial parts, trucks and other vehicles stored outside. At industrial and commercial facilities, drain oil and fuel filters before disposal. Discard empty oil and fuel filters, oily rags, and other oily solid waste into appropriately closed and properly labeled containers, and in compliance with the Uniform Fire Code or International Building Code. 87 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 6 For the storage of liquids use containers, such as steel and plastic drums, that are rigid and durable, corrosion resistant to the weather and fluid content, non-absorbent, water tight, rodent-proof, and equipped with a close fitting cover. For the temporary storage of solid wastes contaminated with liquids or other potential polluted materials use dumpsters, garbage cans, drums, and comparable containers, which are durable, corrosion resistant, non-absorbent, non-leaking, and equipped with either a solid cover or screen cover to prevent littering. If covered with a screen, the container must be stored under a roof or other form of adequate cover. Where exposed to stormwater, use containers, piping, tubing, pumps, fittings, and valves that are appropriate for their intended use and for the contained liquid. Clean oils, debris, sludge, etc. from all stormwater facilities regularly, including catch basins, settling/detention basins, oil/water separators, boomed areas, and conveyance systems to prevent the contamination of stormwater. Refer to Ecology Requirements for Generators of Dangerous Wastes in I-2.15 Other Requirements for references to assist in handling potentially dangerous waste. Promptly repair or replace all substantially cracked or otherwise damaged paved secondary containment, high-intensity parking, and any other drainage areas, subjected to pollutant material leaks or spills. Promptly repair or replace all leaking connections, pipes, hoses, valves, etc., which can contaminate stormwater. Do not connect floor drains in potential pollutant source areas to storm drains, surface water, or to the ground. 1.4.4 S455 – Spill Prevention and Cleanup Spill Prevention Clearly label or mark all containers that contain potential pollutants. Store and transport liquid materials in appropriate containers with tight-fitting lids. Place drip pans underneath all containers, fittings, valves, and where materials are likely to spill or leak. Use tarpaulins, ground cloths, or drip pans in areas where materials are mixed, carried, and applied to capture any spilled materials. Train employees on the safe techniques for handling materials used on the site and to check for leaks and spills. Spill Plan 88 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 7 Develop and implement a spill plan and update it annually or whenever there is a change in activities or staff responsible for spill cleanup. Post a written summary of the plan at areas with a high potential for spills, such as loading docks, product storage areas, waste storage areas, and near a phone. The spill plan may need to be posted at multiple locations. Describe the facility, including the owner's name, address, and telephone number; the nature of the facility activity; and the general types of chemicals used at the facility. Designate spill response employees to be on-site during business activities. Provide a current list of the names and telephone numbers (home and office) of designated spill response employees who are responsible for implementing the spill plan. Provide a site plan showing the locations of storage areas for chemicals, inlets/catch basins, spill kits and other relevant infrastructure or materials information. Describe the emergency cleanup and disposal procedures. Note the location of all spill kits in the spill plan. List the names and telephone numbers of public agencies to contact in the event of a spill. Spill Cleanup Kits Store all cleanup kits near areas with a high potential for spills so that they are easily accessible in the event of a spill. The contents of the spill kit must be appropriate to the types and quantities of materials stored or otherwise used at the facility, and refilled when the materials are used. Spill kits must be located within 25 feet of all fueling/fuel transfer areas, including on-board mobile fuel trucks. Note: Ecology recommends that the kit(s) include salvage drums or containers, such as high density polyethylene, polypropylene or polyethylene sheet-lined steel; polyethylene or equivalent disposal bags; an emergency response guidebook; safety gloves/clothes/equipment; shovels or other soil removal equipment; and oil containment booms and absorbent pads; all stored in an impervious container. Spill Cleanup and Proper Disposal of Waste Stop, contain, and clean up all spills immediately upon discovery. Implement the spill plan immediately. Contact the designated spill response employees. Block off and seal nearby inlets/catch basins to prevent materials from entering the drainage system or combined sewer. Use the appropriate material to clean up the spill. 89 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 8 Do not use emulsifiers or dispersants such as liquid detergents or degreasers unless disposed of proplerly. Emulsifiers and dispersants are not allowed to be used on surface water, or in a place where they may enter storm drains, surface waters, treatments systems, or sanitary sewers. Immediately notify Ecology and the local jurisdiction if a spill has reached or may reach a sanitary or storm sewer, ground water, or surface water. Notification must comply with state and federal spill reporting requirements. Do not wash absorbent material into interior floor drains or inlets/catch basins. Place used spill control materials in appropriate containers and dispose of according to regulations. 1.4.5 S456 – Employee Training Train all employees that work in pollutant source areas about the following topics: Identifying Pollution Prevention Team Members. Identifying pollutant sources. Understanding pollutant control measures. Spill prevention and response. Emergency response procedures. Handling practices that are environmentally acceptable. Particularly those related to vehicle/equipment liquids such as fuels, and vehicle/equipment cleaning. 1.4.6 S457 – Inspections Qualified personnel shall conduct inspections monthly. Make and maintain a record of each inspection on-site. The following requirements apply to inspections: Be conducted by someone familiar with the facility's site, operations, and BMPs. Verify the accuracy of the pollutant source descriptions in the SWPPP. Assess all BMPs that have been implemented for effectiveness and needed maintenance and locate areas where additional BMPs are needed. Reflect current conditions on the site. 90 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 9 Include written observations of the presence of floating materials, suspended solids, oil and grease, discoloration, turbidity and odor in the stormwater discharges; in outside vehicle maintenance/repair; and liquid handling, and storage areas. In areas where acid or alkaline materials are handled or stored use a simple litmus or pH paper to identify those types of stormwater contaminants where needed. Eliminate or obtain a permit for unpermitted non-stormwater discharges to storm drains or receiving waters, such as process wastewater and vehicle/equipment washwater. Identify actions to address inspection deficiencies. 1.4.7 S458 – Record Keeping See the applicable permit for specific record-keeping requirements and retention schedules for the following reports. At a minimum, retain the following reports for five years: Inspection reports which should include: o Time and date of the inspection o Locations inspected o Statement on status of compliance with the permit o Summary report of any remediation activities required o Name, title, and signature of person conducting the inspection Reports on spills of oil or hazardous substances in greater than Reportable Quantities (Code of Federal Regulations Title 40 Parts 302.4 and 117). Report spills of the following: antifreeze, oil, gasoline, or diesel fuel, that cause: o A violation of the State of Washington's Water Quality Standards. o A film or sheen upon or discoloration of the waters of the State or adjoining shorelines. o A sludge or emulsion to be deposited beneath the surface of the water or upon adjoining shorelines. To report a spill or to determine if a spill is a substance of a Reportable Quantity, call the Ecology regional office and ask for an oil spill operations or a dangerous waste specialist: Northwest Region (425)649-7000 In addition, call the Washington Emergency Management Division at 1-800-258-5990 or 1- 800-OILS-911 AND the National Response Center at 1-800-424-8802. 91 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 10 1.4.8 S406 – Streets and Highways Deicing and Anti-Icing Operations Adhere to manufacturer's guidelines and industry standards of use and application. Store and transfer de and anti-icing materials on impervious containment pads, or an equivalent spill/leak containment area in accordance with S429 BMPs for Storage or Transfer (Outside) of Solid Raw Materials, Byproducts, or Finished Products. Sweep/clean up accumulated de and anti-icing materials and grit from roads as soon as possible after the road surface clears. Minimize use in areas where runoff or spray from the roadway immediately enters sensitive areas such as fish-bearing streams. Maintenance Operations Use drip pans or absorbents wherever concrete, asphalt, asphalt emulsion, paint product, and drips are likely to spill, such as beneath discharge points from equipment. Cover and contain nearby storm drains to keep runoff from entering the drainage system. Collect and contain all solids, slurry, and rinse water. Do not allow these to enter gutters, storm drains, or drainage ditches or onto the paved surface of a roadway or driveway. Designate an area onsite for washing hand tools and collect that water for disposal. Conduct all fueling of equipment in accordance with S419 BMPs for Mobile Fueling of Vehicles and Heavy Equipment. Do not use diesel fuel for cleaning or prepping asphalt tools and equipment. Sweep areas as frequently as needed. Collect all loose aggregate and dust for disposal. Do not hose down areas into storm drains. Store all fuel, paint, and other products on secondary containment. Conduct paint striping operations during dry weather. 1.4.9 S417 – Maintenance of Stormwater Drainage and Treatment Systems Maintain stormwater treatment facilities per the operations and maintenance (O&M) procedures presented in Appendix V-A: BMP Maintenance Tables (included below for infiltration and permeable pavement) in addition to the following BMPs: 92 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 11 Inspect and clean treatment BMPs, conveyance systems, and catch basins as needed, and determine necessary O&M improvements. Promptly repair any deterioration threatening the structural integrity of stormwater facilities. These include replacement of clean-out gates, catch basin lids, and rock in emergency spillways. Ensure adequacy of storm sewer capacities and prevent heavy sediment discharges to the sewer system. Regularly remove debris and sludge from BMPs used for peak-rate control, treatment, etc. and discharge to a sanitary sewer if approved by the sewer authority, or truck to an appropriate local or state government approved disposal site. Clean catch basins when the depth of deposits reaches 60 percent of the sump depth as measured from the bottom of basin to the invert of the lowest pipe into or out of the basin. However, in no case should there be less than six inches clearance from the debris surface to the invert of the lowest pipe. Some catch basins (for example, WSDOT's Catch Basin Type 1L (WSDOT, 2011)) may have as little as 12 inches sediment storage below the invert. These catch basins need frequent inspection and cleaning to prevent scouring. Where these catch basins are part of a stormwater collection and treatment system, the system owner/operator may choose to concentrate maintenance efforts on downstream control devices as part of a systems approach. Properly dispose of all solids, polluted material, and stagnant water collected through system cleaning. Do not decant water back into the drainage system from eductor trucks or vacuum equipment since there may be residual contaminants in the cleaning equipment. Do not jet material downstream into the public drainage system. Clean woody debris in a catch basin as frequently as needed to ensure proper operation of the catch basin. Post warning signs; “Dump No Waste - Drains to Ground Water,” “Streams,” “Lakes,” or emboss on or adjacent to all storm drain inlets where possible. Disposal of sediments and liquids from the catch basins must comply with Appendix IV-B: Management of Street Waste Solids and Liquids 1.4.10 S430 – Urban Streets Conduct efficient street sweeping where and when appropriate to minimize the contamination of stormwater. Do not wash street debris into storm drains. 93 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 12 1.4.11 S411 – Landscaping, Lawn, and Vegetation Management Install engineered soil/landscape systems to improve the infiltration and regulation of stormwater in landscaped areas. Select the right plants for the planting location based on proposed use, available maintenance, soil conditions, sun exposure, water availability, height, sight factors, and space available. Ensure that plants selected for planting are not on the noxious weed list. For example, butterfly bush often gets planted as an ornamental but is actually on the noxious weed list. The Washington State Noxious Weed List can be found at the following webpage: https://www.nwcb.wa.gov/printable-noxious-weed-list Do not dispose of collected vegetation into waterways or storm sewer systems. Do not blow vegetation or other debris into the drainage system. Dispose of collected vegetation such as grass clippings, leaves, sticks by composting or recycling. Remove, bag, and dispose of class A & B noxious weeds in the garbage immediately. Do not compost noxious weeds as it may lead to spreading through seed or fragment if the composting process is not hot enough. Use manual and/or mechanical methods of vegetation removal (pincer-type weeding tools, flame weeders, or hot water weeders as appropriate) rather than applying herbicides, where practical. Use at least an eight-inch "topsoil" layer with at least 8 percent organic matter to provide a sufficient vegetation-growing medium. Organic matter is the least water-soluble form of nutrients that can be added to the soil. Composted organic matter generally releases only between 2 and 10 percent of its total nitrogen annually, and this release corresponds closely to the plant growth cycle. Return natural plant debris and mulch to the soil, to continue recycling nutrients indefinitely. Select the appropriate turfgrass mixture for the climate and soil type. Certain tall fescues and rye grasses resist insect attack because the symbiotic endophytic fungi found naturally in their tissues repel or kill common leaf and stem-eating lawn insects. 94 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 13 The fungus causes no known adverse effects to the host plant or to humans. Tall fescues and rye grasses do not repel root-feeding lawn pests such as Crane Fly larvae. Tall fescues and rye grasses are toxic to ruminants such as cattle and sheep Endophytic grasses are commercially available; use them in areas such as parks or golf courses where grazing does not occur. Local agricultural or gardening resources such as Washington State University Extension office can offer advice on which types of grass are best suited to the area and soil type. Use the following seeding and planting BMPs, or equivalent BMPs, to obtain information on grass mixtures, temporary and permanent seeding procedures, maintenance of a recently planted area, and fertilizer application rates: BMP C120: Temporary and Permanent Seeding, BMP C121: Mulching, BMP C123: Plastic Covering, and BMP C124: Sodding. Adjusting the soil properties of the subject site can assist in selection of desired plant species. Consult a soil restoration specialist for site-specific conditions. 1.4.12 S435 – Pesticides and an Integrated Pest Management Program Train employees on proper application of pesticides and disposal practices. Follow manufacturers’ application guidelines and label requirements. Do not apply pesticides in quantities that exceed the limits on the product the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) label. Avoid excessive application of chemical. Conduct spray applications during weather conditions as specified in the label requirements and applicable local and state regulations. Do not apply during rain or immediately before expected rain (unless the label directs such timing). Clean up any spilled pesticides immediately. Do not hose down to a storm drain, conveyance ditch, or water body. Remove weeds/vegetation in stormwater ditches, stormwater facilities, and drainage systems by hand or other mechanical means and only use pesticides as a last resort. Flag all sensitive areas including wells, creeks, and wetlands prior to spraying. Post notices and delineate the spray area prior to the application, as required by the local jurisdiction, or by Ecology. 95 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 14 Refer to S411 BMPs for Landscaping and Lawn / Vegetation Management and use pesticides only as a last resort. Conduct any pest control activity at the life stage when the pest is most vulnerable. For example, if it is necessary to use a Bacillus thuringiens application to control tent caterpillars, apply it to the material before the caterpillars cocoon or it will be ineffective. Any method used should be site-specific and not used wholesale over a wide area. Mix pesticides and clean the application equipment under cover in an area where accidental spills will not enter surface or ground waters, and will not contaminate the soil. The pesticide application equipment must be capable of immediate shutoff in the event of an emergency. Implement a pesticide-use plan and include at a minimum: o A list of selected pesticides and their specific uses. o Brands and formulations of the pesticides. o Application methods and quantities to be used. o Equipment use and maintenance procedures. o Safety, storage, and disposal methods. o Monitoring, record keeping, and public notice procedures. All procedures shall conform to the requirements of Chapter 17.21 RCW and Chapter 16-228 WAC. Develop and implement an Integrated Pest Management (IPM) program if pests are present. The following steps are adapted from (Daar, 1992). o Step One: Correctly identify problem pests and understand their life cycle. Learn more about the pest. Observe it and pay attention to any damage that may be occurring. Learn about the life cycle. Many pests are only a problem during certain seasons, or can only be treated effectively in certain phases of the life cycle. o Step Two: Establish tolerance thresholds for pests. 96 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 15 Decide on the level of infestation that must be exceeded before treatment needs to be considered. Pest populations under this threshold should be monitored but don’t need treatment. o Step Three: Monitor to detect and prevent pest problems. Monitor regularly to anticipate and prevent major pest outbreaks. Conduct a visual evaluation of the lawn or landscape's condition. Take a few minutes before mowing to walk around and look for problems. Keep a notebook, record when and where a problem occurs, then monitor for it at about the same time in future years. Specific monitoring techniques can be used in the appropriate season for some potential problem pests, such as European crane fly. o Step Four: Modify the maintenance program to promote healthy plants and discourage pests. Review your landscape maintenance practices to see if they can be modified to prevent or reduce the problem. A healthy landscape is resistant to most pest problems. Lawn aeration and overseeding along with proper mowing height, fertilization, and irrigation will help the grass out-compete weeds. Correcting drainage problems and letting soil dry out between waterings in the summer may reduce the number of crane-fly larvae that survive. o Step Five: If pests exceed the tolerance thresholds: Consider the most effective management options concurrent with reducing impacts to the environment. This may mean chemical pesticides are the best option in some circumstances. Consider the use of physical, mechanical, or biological controls. Study to determine what products are available and choose a product that is the least toxic and has the least non-target impact. o Step Six: Evaluate and record the effectiveness of the control, and modify maintenance practices to support lawn or landscape recovery and prevent recurrence. Keep records! 97 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 16 Note when, where, and what symptoms occurred, or when monitoring revealed a potential pest problem. Note what controls were applied and when, and the effectiveness of the control. Monitor next year for the same problems. 1.4.13 S450 – Irrigation Irrigate with the minimum amount of water needed. Never water at rates that exceed the infiltration rate of the soil. Maintain all irrigation systems so that irrigation water is applied evenly and where it is needed. Ensure sprinkler systems do not overspray vegetated areas resulting in excess water discharging into the drainage system. Inspect irrigated areas for excess watering. Adjust watering times and schedules to ensure that the appropriate amount of water is being used to minimize runoff. Consider factors such as soil structure, grade, time of year, and type of plant material in determining the proper amounts of water for a specific area. Inspect irrigated areas regularly for signs of erosion and / or discharge. Place sprinkler systems appropriately so that water is not being sprayed on impervious surfaces instead of vegetation. Repair broken or leaking sprinkler nozzles as soon as possible. Appropriately irrigate lawns based on the species planted, the available water holding capacity of the soil, and the efficiency of the irrigation system. The depth from which a plant normally extracts water depends on the rooting depth of the plant. Appropriately irrigated lawn grasses normally root in the top 6 to 12 inches of soil; lawns irrigated on a daily basis often root only in the top 1 inch of soil. Do not irrigate plants during or immediately after fertilizer application. The longer the period between fertilizer application and irrigation, the less fertilizer runoff occurs. Do not irrigate plants during or immediately after pesticide application (unless the pesticide label directs such timing). Reduce frequency and / or intensity of watering as appropriate for the wet season (October 1 to April 30). 98 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 17 Place irrigation systems to ensure that plants receive water where they need it. For example, do not place irrigation systems downgradient of plant’s root zones on hillsides. 1.4.14 S443 – Fertilizer Application Apply the minimum amount of slow-release fertilizer necessary to achieve successful plant establishment. Do not fertilize when the soil is dry or during a drought. Never apply fertilizers if it is raining or about to rain. Do not apply fertilizers within three days prior to predicted rainfall. The longer the period between fertilizer application and either rainfall or irrigation, the less fertilizer runoff occurs. Determine the proper fertilizer application for the types of soil and vegetation involved. Follow manufacturers’ recommendations and label directions. Train employees on the proper use and application of fertilizers. Keep fertilizer granules off impervious surfaces. Clean up any spills immediately. Do not hose down to a storm drain, conveyance ditch, or water body. If possible, do not fertilize areas within 100 feet of water bodies including wetlands, ponds, and streams. Avoid fertilizer applications in stormwater ditches, stormwater facilities, and drainage systems. In areas that drain to sensitive water bodies, apply no fertilizer at commercial and industrial facilities, to grass swales, filter strips, or buffer areas unless approved by the local jurisdiction. Use slow release fertilizers such as methylene urea, isobutylidene, or resin coated fertilizers when appropriate, generally in the spring. Use of slow release fertilizers is especially important in areas with sandy or gravelly soils. Apply fertilizers in amounts appropriate for the target vegetation and at the time of year that minimizes losses to surface and ground waters. Time the fertilizer application to periods of maximum plant uptake. Ecology generally recommends application in the fall and spring, although Washington State University turf specialists recommend four fertilizer applications per year. 99 of 347 21-3259 Garden Avenue Realignment Stormwater Site Plan March 2023 City of Auburn • Page 18 Do not use turf fertilizers containing phosphorous unless a soil sample analysis taken within the past 36 months indicates the soil of the established lawn is deficient in phosphorus. For more information about restrictions on turf fertilizers containing phosphorus, see the following website: o https://agr.wa.gov/departments/pesticides-and-fertilizers/fertilizers/fertilizers- containing-phosphorus 1.5 Maintenance Tables and Maintenance Log The following pages include maintenance tables from the 2019 WWSWMM for bioretention facilities and permeable pavements. Following those tables is an example maintenance log for recording regular maintenance events. 100 of 347 Appendix B Construction Stormwater Pollution Prevention Plan 101 of 347 21-3259 Page 1 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Construction Stormwater General Permit (CSWGP) Stormwater Pollution Prevention Plan (SWPPP) for Garden Avenue Realignment Prepared for: Department of Ecology Northwest Region Permittee / Owner Developer Operator / Contractor City of Auburn City of Auburn TBD SE 318th Street and 102nd Avenue SE, Auburn, WA Certified Erosion and Sediment Control Lead (CESCL) or Inspector Name Organization Contact Phone Number TBD TBD TBD SWPPP Prepared By Name Organization Contact Phone Number Katie Husk, P.E.Consor 206.462.7030 SWPPP Preparation Date March / 17 / 2023 Project Construction Dates Activity / Phase Start Date End Date [Insert Text]MM / DD / YYYY MM / DD / YYYY 102 of 347 21-3259 Page 2 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Table of Contents List of Acronyms and Abbreviations ............................................................................................................4 Project Information (1.0).............................................................................................................................5 Existing Conditions (1.1) ...........................................................................................................................5 Proposed Construction Activities (1.2) .....................................................................................................6 Contstuction Stormwater Best Management Practices (BMPs) (2.0).........................................................7 The 13 Elements (2.1)...............................................................................................................................7 Element 1: Preserve Vegetation / Mark Clearing Limits (2.1.1)............................................................7 Element 2: Establish Construction Access (2.1.2).................................................................................8 Element 3: Control Flow Rates (2.1.3)..................................................................................................9 Element 4: Install Sediment Controls (2.1.4)......................................................................................10 Element 5: Stablize Soils (2.1.5)..........................................................................................................11 Element 6: Protect Slopes (2.1.6) .......................................................................................................14 Element 7: Protect Drain Inlets (2.1.7) ...............................................................................................15 Element 8: Stabilize Channels and Outlets (2.1.8)..............................................................................16 Element 9: Control Pollutants (2.1.9) .................................................................................................17 Element 10: Control Dewatering (2.1.10)...........................................................................................20 Element 11: Maintain BMPs (2.1.11)..................................................................................................21 Element 12: Manage the Project (2.1.12)...........................................................................................22 Element 13: Protect Low Impact Development (LID) BMPs (2.1.13)..................................................24 Pollution Prevention Team (3.0)................................................................................................................24 Monitoring and Sampling Requirements (4.0)..........................................................................................25 Site Inspection (4.1)................................................................................................................................25 Stormwater Quality Sampling (4.2).........................................................................................................25 Turbidity Sampling (4.2.1)...................................................................................................................25 pH Sampling (4.2.2) ............................................................................................................................27 Discharges to 303(d) or Total Maximum Daily Load (TMDL) Waterbodies (5.0)......................................28 303(d) Listed Waterbodies (5.1).............................................................................................................28 TMDL Waterbodies (5.2).........................................................................................................................28 Reporting and Record Keeping (6.0)..........................................................................................................29 Record Keeping (6.1)...............................................................................................................................29 Site Log Book (6.1.1)...........................................................................................................................29 103 of 347 21-3259 Page 3 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Records Retention (6.1.2)...................................................................................................................29 Updating the SWPPP (6.1.3)...............................................................................................................29 Reporting (6.2)........................................................................................................................................30 Discharge Monitoring Reports (6.2.1) ................................................................................................30 Notification of Noncompliance...........................................................................................................30 List of Tables Table 1 - Pollutants.................................................................................................................................17 Table 2 – pH-Modifying Sources.............................................................................................................19 Table 3 - Management............................................................................................................................22 Table 4 – BMP Implementation Schedule...............................................................................................23 Table 5 – Team Information....................................................................................................................24 Table 6 – Turbidity Sampling Method.....................................................................................................25 Table 7 – pH Sampling Method...............................................................................................................27 List of Appendicies A. Site Map ...........................................................................................................................................31 B. BMP Details......................................................................................................................................XX C. Correspondence...............................................................................................................................XX D. Site Inspection Form.........................................................................................................................XX E. Construction Stormwater General Permit (CSWGP)........................................................................XX F. Engineering Calculations..................................................................................................................XX 104 of 347 21-3259 Page 4 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn List of Acronyms and Abbreviations Acronym / Abbreviation Explanation 303(d)Section of the Clean Water Act pertaining to Impaired Waterbodies BFO Bellingham Field Office of the Department of Ecology BMP(s)Best Management Practice(s) CESCL Certified Erosion and Sediment Control Lead CO2 Carbon Dioxide CRO Central Regional Office of the Department of Ecology CSWGP Construction Stormwater General Permit CWA Clean Water Act DMR Discharge Monitoring Report DO Dissolved Oxygen Ecology Washington State Department of Ecology EPA United States Environmental Protection Agency ERO Eastern Regional Office of the Department of Ecology ERTS Environmental Report Tracking System ESC Erosion and Sediment Control GULD General Use Level Designation NPDES National Pollutant Discharge Elimination System NTU Nephelometric Turbidity Units NWRO Northwest Regional Office of the Department of Ecology pH Power of Hydrogen RCW Revised Code of Washington SPCC Spill Prevention, Control, and Countermeasure su Standard Units SWMMEW Stormwater Management Manual for Eastern Washington SWMMWW Stormwater Management Manual for Western Washington SWPPP Stormwater Pollution Prevention Plan TESC Temporary Erosion and Sediment Control SWRO Southwest Regional Office of the Department of Ecology TMDL Total Maximum Daily Load VFO Vancouver Field Office of the Department of Ecology WAC Washington Administrative Code WSDOT Washington Department of Transportation WWHM Western Washington Hydrology Model 105 of 347 21-3259 Page 5 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Project Information (1.0) Project/Site Name: CP-2002 Garden Avenue Realignment Street/Location: SE 318th Street and 102nd Avenue SE City: Auburn State: WA Zip code: 98092 Subdivision: Lea Hill Receiving waterbody: Green River Existing Conditions (1.1) Total acreage (including support activities such as off-site equipment staging yards, material storage areas, borrow areas). Total acreage: 0.84 Disturbed acreage: 0.84 Existing structures: There is an existing fence, some existing roadway, and a tree which may need to be removed. Landscape topography: The project site is relatively level with minimal grade change. Drainage patterns: There are no significant drainage patterns – runoff infiltrates through dispersion Existing Vegetation: The local foliage includes grasses, blackberry bushes, thin alders and maples, and short brush. The widened street sections and sidewalk will be constructed in areas that are currently covered with short grasses and gravel. Critical Areas: Riparian Habitat Zone of the Green River, Zone 2 Groundwater Protection Area There are no known impairments for 303(d) listed or Total Maximum Daily Load (TMDL) for the receiving waterbody. Table 1 is not used because there are no suspected and/or known contaminants associated with the construction activity. 106 of 347 21-3259 Page 6 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Proposed Construction Activities (1.2) Description of site development: Roadway widening, half-street improvements, new roadway connection (intersection), and new cul-de-sac. Description of construction activities: Site preparation, excavation, backfill, paving (including grind and overlay), landscaping Description of site drainage including flow from and onto adjacent properties. Must be consistent with Site Map in Appendix A: There is no anticipated run-on from off-site. Runoff is infiltrated via dispersion. Description of final stabilization: Paving 0.55 acres, pervious concrete to cover 0.23 acres, and landscaping on 0.06 acres Contaminated Site Information: Proposed activities regarding contaminated soils or groundwater (example: on-site treatment system, authorized sanitary sewer discharge): There is no known contamination within the site area 107 of 347 21-3259 Page 7 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Construction Stormwater Best Management Practices (BMPs) (2.0) The SWPPP is a living document reflecting current conditions and changes throughout the life of the project. These changes may be informal (i.e. hand-written notes and deletions). Update the SWPPP when the CESCL has noted a deficiency in BMPs or deviation from original design. The 13 Elements (2.1) Element 1: Preserve Vegetation / Mark Clearing Limits (2.1.1) List and describe BMPs: C101: Preserve Natural Vegetation o Conditions of Use o Natural vegetation should be preserved on steep slopes, near perennial and intermittent watercourses or swales, and on building sites in wooded areas. Local government may have additional requirements. When necessary and possible, phase construction to preserve natural vegetation on the project site for as long as possible. o Design and Installation Specifications Natural vegetation can be preserved in clumps or as individual plants. Plants need protection from three kinds of injuries, construction equipment, grade changes, and excavations. o Maintenance Standards Inspect flagged and/or fenced areas regularly, replace markings as necessary. Prune exposed or injured tree roots and recover with native soil as necessary and applicable. C103: High Visibility Fence – o Restrict clearing to approved limits. o Prevent disturbance of sensitive areas, their buffers, and other areas required to be left undisturbed. o Limit construction traffic to designated construction entrances, exits, or internal roads. o Protect areas where marking with survey tape may not provide adequate protection Installation Schedules: Prior to soil disturbance. Inspection and Maintenance plan: Inspect and maintain weekly Responsible Staff: TBD 108 of 347 21-3259 Page 8 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 2: Establish Construction Access (2.1.2) List and describe BMPs: Construction access will primarily occur within existing paved areas. In the event that vehicles need to travel over unpaved areas, only stabilized access points will be utilized to reduce the amount of sediment transported onto paved roads surrounding the project. C105: Stabilized Construction Access o Conditions of Use Construction accesses shall be stabilized wherever traffic will be entering or leaving a construction site if paved roads or other paved areas are within 1,000 feet of the site. o Design and Installation Specification Construct stabilized construction accesses with a 12-inch thick pad of 4-inch to 8- inch quarry spalls, a 4-inch course of asphalt treated base (ATB), or use existing pavement. Do not use crushed concrete, cement, or calcium chloride for construction access stabilization because these products raise pH levels in stormwater and concrete discharge to waters of the State is prohibited. A separation geotextile shall be placed under the spalls to prevent fine sediment from pumping up into the rock pad o Maintenance Standards Quarry spalls shall be added if the pad is no longer in accordance with the spcifications. Monitor pavement for tracked sediment and remove by shoveling or high-efficiency street sweeping. C106: Wheel Wash o Conditions of Use Use a wheel wash only when stabilized construction access is not preventing sediment from being tracked off site. Note that wheel wash water is not stormwater; it is process water and must be discharged to a separate on-site treatment system or to the local sanitary sewer, with local sewer district approval. o Design and Installation Specifications Suggested details per Figure II-3.2, per the 2019 SWMMWW Use a low clearance truck to test the wheel wash set up, as applicable. o Maintenance Standards Start each day with fresh water Installation Schedules: Installed as needed prior to ground disturbing activities Inspection and Maintenance plan: Roadway will be swept regularly as needed to keep clean Responsible Staff: TBD 109 of 347 21-3259 Page 9 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 3: Control Flow Rates (2.1.3) Describe how you will protect properties and waterways downstream of the project from increased speed and volume of stormwater discharges due to construction activity. Construction of stormwater retention and/or detention facilities must be done as one of the first steps in grading. Assure that detention facilities are functioning properly before constructing site improvements (i.e. impervious surfaces). If applicable, describe how you will protect areas designed for infiltration from siltation during the construction phase. Will you construct stormwater retention and/or detention facilities? Yes No Will you use permanent infiltration ponds or other low impact development (example: rain gardens, bio-retention, porous pavement) to control flow during construction? Yes No List and describe BMPs: None Anticipated Installation Schedules: N/A Inspection and Maintenance plan: N/A Responsible Staff: N/A 110 of 347 21-3259 Page 10 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 4: Install Sediment Controls (2.1.4) Describe how you will minimize sediment discharges from the site. Construct sediment control BMPs as one of the first steps of grading. These BMPs must be functional before other land disturbing activities – especially grading and filling – take place. Describe the BMPs identified to filter sediment prior to it being discharged to an infiltration system or leaving the construction site. Describe how you will direct stormwater for maximum infiltration where feasible. Describe how you will not interfere with the movement of juvenile Salmonids attempting to enter off-channel areas or drainages. Describe how you will respond if sediment controls are ineffective and turbid water is observed discharging from the site. Consider the amount, frequency, intensity and duration of precipitation, soil characteristics, and site characteristics when selecting sediment control BMPs. List and describe BMPs: C233: Silt Fence o Conditions of Use May be used downslope of all disturbed areas, for no deeper than sheet flow and no steeper than 1:1 slopes. o Design and Installation Specifications Intended use in combination with other construction stormwater BMPs. Use geotextile fabrics meeting or exceeding Ecology standards and properly support fabrics with fence posts and wire. o Maintenance Standards Repair damage, remove sediment build-up, and direct concentrated flows through a sediment trapping BMP. Installation Schedules: Prior to construction Inspection and Maintenance plan: Inspect and maintain weekly Responsible Staff: TBD 111 of 347 21-3259 Page 11 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 5: Stabilize Soils (2.1.5) Describe how you will stabilize exposed and unworked soils throughout the life of the project (i.e. temporary and permanent seeding, mulching, erosion control fabrics, etc.). Describe how you will stabilize soil stockpiles. Describe how you will minimize the amount of soil exposed throughout the life of the project. Describe how you will minimize the disturbance of steep slopes. Describe how you will minimize soil compaction. Describe how you will stabilize contaminated soil and contaminated soil stockpiles if applicable. Exposed and unworked soils will be stabilized according to the time period set forth for dry and wet seasons, on the west or east sides of the crest of the Cascade Mountains. West of the Cascade Mountains Crest Season Dates Number of Days Soils Can be Left Exposed During the Dry Season May 1 – September 30 7 days During the Wet Season October 1 – April 30 2 days Soils must be stabilized at the end of the shift before a holiday or weekend if needed based on the weather forecast. Anticipated project dates:Start date: TBD End date: TBD Will you construct during the wet season? Yes No List and describe BMPs: Temporary and permanent seeding, sodding, mulching plastic covering, erosion control fabrics and matting, soil application of polyacryliamide (PAM), early application of gravel base on areas to be paved, and dust control C120: Temporary and Permanent Seeding o Conditions of Use 112 of 347 21-3259 Page 12 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Use seeding on disturbed areas that will remain unworked for more than 30 days. Pay special attention to potential seeding needs before the end of optimum seeding windows in the end of June and the end of September. o Design and Installation Specifications Establish 75 percent vegetation cover before allowing water to flow. Use applicable seeding mix for temporary erosion control, landscaping, low-growing turf, bioswale, wet areas, and meadows. o Maintenance Standards Areas which fail to establish 75 percent must be reseeded. When reseeding is ineffective, alternative methods should be used. C121: Mulching o Conditions of Use Mulch should be used no more than 30 days on disturbed areas that require cover, at all times for seeded areas o Design and Installation Specifications Consult with local supplier or the local conservation district for their recommendations with respect to mulch materials, application rates, and specifications o Maintenance Standards The thickness of mulch cover shall be maintained. Areas that experience erosion shall be remulched or reevaluated for erosion control measures. C123: Plastic Covering o Conditions of Use Plastic sheeting may be used on disturbed areas that require cover measures for less than 30 days. o Design and Installation Specifications Plastic sheeting to be applied up and down slopes, with 8 inches of overlap at seams, seams to be taped when high winds present. o Maintenance Standards Plastic sheets shall be checked for tears, open seams and deterioration due to ultraviolet light. Plastic will be replaced or repaired as necessary. C124: Sodding o Cnonditions of Use Sodding can be used as short-term or long-term cover and in waterways which require immediate vegetative lining. o Design and Installation Specifications Sod shall be free of weeds, of uniform thickness, and have dense root mat for mechanical strength. o Maintenance Standards If grass is unhealthy, the cause shall be determined and appropriate corrective action taken to reestablish a healthy groundcover. C126: Polyacrylamide (PAM) for Soil Erosion Protection o Conditions of Use 113 of 347 21-3259 Page 13 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn PAM shall not be applied directly to water or allowed to enter a water body. PAM can be applied to bare soil under certain conditions. o Design and Installation Specifications When using PAM on a site, maximize the use of silt fence to limit the discharge of sediment from the site. Apply PAM using the preferred method whenever possible. o Maintenance Standards PAM may be reapplied on actively worked areas after 48 hours, but reapplication is not required unless PAM treated soil is disturbed or turbidity levels show the need for additional application. C140: Dust Control o Conditions of Use Use dust control in areas subject to surface and air movement of dust where on- site or off-site impacts to roadways, drainage ways, or surface waters are likely. o Design and Installation Specifications Vegetate or mulch areas without vehicle traffic. Clear only areas where immediate activity will take place. Construct windbreaks. Sprinkle the site with water to keep surface wet or apply a dust palliative following manufacturer’s instructions. Use vacuum street sweepers. Keep speeds low when traveling on unpaved surfaces, add gravel and limit the amount of fines, use geotextiles, and encourage the use of alternative paved routes whenever possible. Limit dust- causing work on windy days. o Maintenance Standards Respray and reroute construction site when necessary Installation Schedules: Once ground disturbing activities are started and/or stockpiles are present Inspection and Maintenance plan: Inspect and maintain weekly or as needed Responsible Staff: TBD 114 of 347 21-3259 Page 14 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 6: Protect Slopes (2.1.6) Will steep slopes be present at the site during construction? Yes No List and describe BMPs: There are not steep slopes on or adjacent to the project site Installation Schedules: N/A Inspection and Maintenance plan: N/A Responsible Staff: N/A 115 of 347 21-3259 Page 15 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 7: Protect Drain Inlets (2.1.7) List and describe BMPs: There are no drain inlets within or adjacent to the project site. Installation Schedules: N/A Inspection and Maintenance plan: N/A Responsible Staff: N/A 116 of 347 21-3259 Page 16 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 8: Stabilize Channels and Outlets (2.1.8) List and describe BMPs: There are no surface channel outlets proposed for this project. Installation Schedules: N/A Inspection and Maintenance plan: N/A Responsible Staff: N/A 117 of 347 21-3259 Page 17 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 9: Control Pollutants (2.1.9) There are no known or suspected existing pollutants. Pollutants anticipated to be present on- site are limited to typical construction activities: Table 1 – Pollutants Pollutant (and source, if applicable) Gas and diesel fuel Petroleum products Concrete wash List and describe BMPs: C150: Materials on Hand o Conditions of Use Provide immediate protection of bare soil on which materials will be stored. Materials should be stockpiled and ready before and site clearing, grubbing, or earthwork begins. o Design and Installation Criteria Materials and quantity will vary by site. o Maintenance Standards All materials with the exception of quarry spalls, steel “T” posts, and gravel should be kept covered and out of both sun and rain. C153: Material Delivery, Storage, and Containment o Conditions of Use Petroleum products; soil stabilizers and binders; fertilizers, pesticides, and herbicides; detergents; asphalt and concrete compounds; hazardous chemicals such as acids, lime, adhesives, paints, solvents, and curing compounds; any other material that may be detrimental is released to the environment. o Design and Installation Criteria Hazardous material storage on-site should be minimized. When necessary, temporary storage areas shall be designated and secondary containment provided. Safety Data Sheets (SDS) should be supplied for all materials stored. o Maintenance Standards Secondary containment facilities shall be maintained free of acculumated rainwater and spills. In the event of spills or leaks, accumulated rainwater and spills shall be collected and placed into drums. These liquids shall be handled as hazardous waste unless testing determines them to be non-hazardous. Installation Schedules: Prior to pollutant generating activities 118 of 347 21-3259 Page 18 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Inspection and Maintenance plan: Inspect and maintain weekly Responsible Staff: TBD Will maintenance, fueling, and/or repair of heavy equipment and vehicles occur on-site? Yes No If yes, describe spill prevention and control measures in place while conducting maintenance, fueling, and repair of heavy equipment and vehicles. If yes, also provide the total volume of fuel on-site and capacity of the secondary containment for each fuel tank. Secondary containment structures shall be impervious. All vehicles, equipment, and petroleum product storage/dispensing areas will be inspected regularly to detect any leaks or spills, and to identify maintenance needs to prevent leaks or spills. On-site fueling tanks and petroleum product storage containers shall include secondary containment. Spill prevention measures, such as drip pans, will be used when conducting maintenance and repair of vehicles or equipment. In order to perform emergency repairs on site, temporary plastic will be placed beneath and, if raining, over the vehicle. Contaminated surfaces shall be cleaned immediately following any discharge or spill incident. A Spill Prevention, Control and Countermeasure Plan would be developed and implemented by the Contractor in order to protect land and water resources. List and describe BMPs: BMP C153: Materials Delivery, Storage and Containment o This process is used to store materials in safe areas with secondary containment. This includes a spill kit on-site. Installation Schedules: Prior to construction Inspection and Maintenance plan: Inspect and maintain weekly Responsible Staff: TBD 119 of 347 21-3259 Page 19 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Will wheel wash or tire bath system BMPs be used during construction? Yes No If yes, provide disposal methods for wastewater generated by BMPs. If discharging to the sanitary sewer, include the approval letter from your local sewer district under Correspondence in Appendix C. List and describe BMPs: N/A Installation Schedules: N/A Inspection and Maintenance plan: N/A Responsible Staff: N/A Will pH-modifying sources be present on-site? Yes No If yes, check the source(s). Table 2 – pH-Modifying Sources None x Bulk cement Cement kiln dust Fly ash Other cementitious materials x New concrete washing or curing waters Waste streams generated from concrete grinding and sawing Exposed aggregate processes Dewatering concrete vaults x Concrete pumping and mixer washout waters Recycled concrete Other (i.e. calcium lignosulfate) [please describe] Describe BMPs you will use to prevent pH-modifying sources from contaminating stormwater. List and describe BMPs: BMP C151: Concrete Handling o Prevent concrete slurry and process water from entering existing surface water. 120 of 347 21-3259 Page 20 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn BMP C152: Sawcutting and Surfacing Pollution Prevention o This process prevents slurry from entering surface water. This includes disposing of slurry properly. BMP C153: Materials Delivery, Storage and Containment o This process is used to store materials in safe areas with secondary containment. This includes a spill kit on site. BMP C154: Concrete Washout Area o Use only approved washout facility Installation Schedules: Prior to pollutant generating activities Inspection and Maintenance plan: Inspect and maintain weekly Responsible Staff: TBD Adjust pH of stormwater if outside the range of 6.5 to 8.5 su. Obtain written approval from Ecology before using chemical treatment with the exception of CO2 or dry ice to modify pH. Concrete trucks must not be washed out onto the ground, or into storm drains, open ditches, streets, or streams. Excess concrete must not be dumped on-site, except in designated concrete washout areas with appropriate BMPs installed. 121 of 347 21-3259 Page 21 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 10: Control Dewatering (2.1.10) Groundwater was encountered at 7.5 to 10-feet below the surface, and is not anticipated to be encountered during contruction. No dewatering efforts are anticipated. List and describe BMPs: N/A Installation Schedules: N/A Inspection and Maintenance plan: N/A Responsible Staff: N/A 122 of 347 21-3259 Page 22 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 11: Maintain BMPs (2.1.11) All temporary and permanent Erosion and Sediment Control (ESC) BMPs shall be maintained and repaired as needed to ensure continued performance of their intended function. Maintenance and repair shall be conducted in accordance with each particular BMP specification (see Volume II of the SWMMWW or Chapter 7 of the SWMMEW). Visual monitoring of all BMPs installed at the site will be conducted at least once every calendar week and within 24 hours of any stormwater or non-stormwater discharge from the site. If the site becomes inactive and is temporarily stabilized, the inspection frequency may be reduced to once every calendar month. All temporary ESC BMPs shall be removed within 30 days after final site stabilization is achieved or after the temporary BMPs are no longer needed. Trapped sediment shall be stabilized on-site or removed. Disturbed soil resulting from removal of either BMPs or vegetation shall be permanently stabilized. Additionally, protection must be provided for all BMPs installed for the permanent control of stormwater from sediment and compaction. BMPs that are to remain in place following completion of construction shall be examined and restored to full operating condition. If sediment enters these BMPs during construction, the sediment shall be removed and the facility shall be returned to conditions specified in the construction documents. 123 of 347 21-3259 Page 23 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 12: Manage the Project (2.1.12) The project will be managed based on the following principles: Projects will be phased to the maximum extent practicable and seasonal work limitations will be taken into account. Inspection and monitoring: o Inspection, maintenance and repair of all BMPs will occur as needed to ensure performance of their intended function. o Site inspections and monitoring will be conducted in accordance with Special Condition S4 of the CSWGP. Sampling locations are indicated on the Site Map. Sampling station(s) are located in accordance with applicable requirements of the CSWGP. Maintain an updated SWPPP. o The SWPPP will be updated, maintained, and implemented in accordance with Special Conditions S3, S4, and S9 of the CSWGP. As site work progresses the SWPPP will be modified routinely to reflect changing site conditions. The SWPPP will be reviewed monthly to ensure the content is current. Check all the management BMPs that apply at your site: Table 3 – Management X Design the project to fit the existing topography, soils, and drainage patterns X Emphasize erosion control rather than sediment control X Minimize the extent and duration of the area exposed X Keep runoff velocities low X Retain sediment on-site X Thoroughly monitor site and maintain all ESC measures X Schedule major earthwork during the dry season Other (please describe) 124 of 347 21-3259 Page 24 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Table 4 – BMP Implementation Schedule Phase of Construction Project Stormwater BMPs Date Wet/Dry Season [Insert construction activity] [Insert BMP][MM/DD/YYYY][Insert Season] 125 of 347 21-3259 Page 25 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Element 13: Protect Low Impact Development (LID) BMPs (2.1.13) LID BMPs present on the site include bioretention and permeable pavement. All LID BMPs will be protected from sedimentation through installation and maintenance of erosion and sediment control BMPs. Inlets to LID BMPs will be blocked with wattles or similar devices to keep construction debris out of the facility. If sediment is accumulated to construction, the BMP shall be restored to a fully function condition. All sediment and sediment- laden soils will be removed and replaced with soils that meet the design specifications. All LID BMPs will be protected against compaction by construction equipment and foot traffic. No heavy vehicles or equipment shall drive over proposed locations for LID facilities in order to retain infiltration rates. Extra care shall be taken to protect permeable pavement from sedimentation. Permeable pavement and base material shall be protected from muddy construction equipment and sediment-laden runoff. If permeable pavements become fouled with sediments, they shall be cleaned until restored to initial infiltration rates. Pollution Prevention Team (3.0) Table 5 – Team Information Title Name(s)Phone Number Certified Erosion and Sediment Control Lead (CESCL) TBD TBD Resident Engineer TBD TBD Emergency Ecology Contact Ecology High Turbidity Hotline 425-649-7000 Emergency Permittee/ Owner Contact TBD TBD Non-Emergency Owner Contact TBD TBD Monitoring Personnel TBD TBD Ecology Regional Office Rachel McCrea Water Quality Manager Northwest Region 425-649-7000 126 of 347 21-3259 Page 26 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Monitoring and Sampling Requirements (4.0) Monitoring includes visual inspection, sampling for water quality parameters of concern, and documentation of the inspection and sampling findings in a site log book. A site log book will be maintained for all on-site construction activities and will include: A record of the implementation of the SWPPP and other permit requirements Site inspections Stormwater sampling data Create your own Site Inspection Form or use the Construction Stormwater Site Inspection Form found on Ecology’s website. https://www.ecology.wa.gov/Regulations-Permits/Permits- certifications/Stormwater-general-permits/Construction-stormwater-permit File a blank form under Appendix D. The site log book must be maintained on-site within reasonable access to the site and be made available upon request to Ecology or the local jurisdiction. Numeric effluent limits may be required for certain discharges to 303(d) listed waterbodies. See CSWGP Special Condition S8 and Section 5 of this template. Complete the following paragraph for sites that discharge to impaired waterbodies for fine sediment, turbidity, phosphorus, or pH: The receiving waterbody, Green River, is impaired for: none. All stormwater and dewatering discharges from the site are subject to an effluent limit of 8.5 su for pH and/or 25 NTU for turbidity. Site Inspection (4.1) Site inspections will be conducted at least once every calendar week and within 24 hours following any discharge from the site. For sites that are temporarily stabilized and inactive, the required frequency is reduced to once per calendar month. The discharge point(s) are indicated on the Site Map (see Appendix A) and in accordance with the applicable requirements of the CSWGP. Stormwater Quality Sampling (4.2) Turbidity Sampling (4.2.1) Requirements include calibrated turbidity meter or transparency tube to sample site discharges for compliance with the CSWGP. Sampling will be conducted at all discharge points at least once per calendar week. 127 of 347 21-3259 Page 27 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Method for sampling turbidity: Check the analysis method you will use: Table 6 – Turbidity Sampling Method Turbidity Meter/Turbidimeter (required for disturbances 5 acres or greater in size) X Transparency Tube (option for disturbances less than 1 acre and up to 5 acres in size) The benchmark for turbidity value is 25 nephelometric turbidity units (NTU) and a transparency less than 33 centimeters. If the discharge’s turbidity is 26 to 249 NTU or the transparency is less than 33 cm but equal to or greater than 6 cm, the following steps will be conducted: 1. Review the SWPPP for compliance with Special Condition S9. Make appropriate revisions within 7 days of the date the discharge exceeded the benchmark. 2. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible. Address the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period. 3. Document BMP implementation and maintenance in the site log book. If the turbidity exceeds 250 NTU or the transparency is 6 cm or less at any time, the following steps will be conducted: 1. Telephone or submit an electronic report to the applicable Ecology Region’s Environmental Report Tracking System (ERTS) within 24 hours. https://www.ecology.wa.gov/About-us/Get-involved/Report-an-environmental-issue Northwest Region (King, Kitsap, Island, San Juan, Skagit, Snohomish, Whatcom): (425) 649-7000 2. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible. Address the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period 3. Document BMP implementation and maintenance in the site log book. 4. Continue to sample discharges daily until one of the following is true: Turbidity is 25 NTU (or lower). Transparency is 33 cm (or greater). Compliance with the water quality limit for turbidity is achieved. o 1 - 5 NTU over background turbidity, if background is less than 50 NTU o 1% - 10% over background turbidity, if background is 50 NTU or greater The discharge stops or is eliminated. 128 of 347 21-3259 Page 28 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Discharges to 303(d) or Total Maximum Daily Load (TMDL) Waterbodies (5.0) 303(d) Listed Waterbodies (5.1) The 303(d) status is listed on the Water Quality Atlas: https://ecology.wa.gov/Water- Shorelines/Water-quality/Water-improvement/Assessment-of-state-waters-303d Circle the applicable answer, if necessary: Is the receiving water 303(d) (Category 5) listed for turbidity, fine sediment, phosphorus, or pH? Yes No List the impairment(s): The receiving waterbody, Green River, is impaired for: None. All stormwater and dewatering discharges from the site are subject to an effluent limit of 8.5 su for pH and/or 25 NTU for turbidity. If yes, discharges must comply with applicable effluent limitations in S8.C and S8.D of the CSWGP. Describe the method(s) for 303(d) compliance: List and describe BMPs: N/A TMDL Waterbodies (5.2) The reveiving water is not an impaired waterbody. 129 of 347 21-3259 Page 29 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Reporting and Record Keeping (6.0) Record Keeping (6.1) Site Log Book (6.1.1) A site log book will be maintained for all on-site construction activities and will include: A record of the implementation of the SWPPP and other permit requirements Site inspections Sample logs Records Retention (6.1.2) Records will be retained during the life of the project and for a minimum of three (3) years following the termination of permit coverage in accordance with Special Condition S5.C of the CSWGP. Permit documentation to be retained on-site: CSWGP Permit Coverage Letter SWPPP Site Log Book Permit documentation will be provided within 14 days of receipt of a written request from Ecology. A copy of the SWPPP or access to the SWPPP will be provided to the public when requested in writing in accordance with Special Condition S5.G.2.b of the CSWGP. Updating the SWPPP (6.1.3) The SWPPP will be modified if: Found ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site. There is a change in design, construction, operation, or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the State. The SWPPP will be modified within seven (7) days if inspection(s) or investigation(s) determine additional or modified BMPs are necessary for compliance. An updated timeline for BMP implementation will be prepared. 130 of 347 21-3259 Page 30 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Reporting (6.2) Discharge Monitoring Reports (6.2.1) Cumulative soil disturbance is less than one (1) acre; therefore, Discharge Monitoring Reports (DMRs) will not be submitted to Ecology because water quality sampling is not being conducted at the site. Notification of Noncompliance (6.2.2) If any of the terms and conditions of the permit is not met, and the resulting noncompliance may cause a threat to human health or the environment, the following actions will be taken: 1. Ecology will be notified within 24-hours of the failure to comply by calling the applicable Regional office ERTS phone number (Regional office numbers listed below). 2. Immediate action will be taken to prevent the discharge/pollution or otherwise stop or correct the noncompliance. If applicable, sampling and analysis of any noncompliance will be repeated immediately and the results submitted to Ecology within five (5) days of becoming aware of the violation. 3. A detailed written report describing the noncompliance will be submitted to Ecology within five (5) days, unless requested earlier by Ecology. a. The report must contain a description of the noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and the steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. b. The Permittee must report any unanticipated bypass and/or upset that exceeds any effluent limit in the permit in accordance with the 24-hour reporting requirement contained in 40 C.F.R. 122.41(l)(6). c. Compliance with these requirements does not relieve the Permittee from responsibility to maintain continuous compliance with the terms and conditions of this permit or the resulting liability for failure to comply. Upon request of the Permittee, Ecology may waive the requirement for a written report on a case-by- case basis, if the immediate notification is received by Ecology within 24 hours. Anytime turbidity sampling indicates turbidity is 250 NTUs or greater, or water transparency is 6 cm or less, the Ecology Regional office will be notified by phone within 24 hours of analysis as required by Special Condition S5.A of the CSWGP. Northwest Region at (425) 649-7000 for Island, King, Kitsap, San Juan, Skagit, Snohomish, or Whatcom County Include the following information: 1. Your name and / Phone number 2. Permit number 131 of 347 21-3259 Page 31 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn 3. City / County of project 4. Sample results 5. Date / Time of call 6. Date / Time of sample 7. Project name In accordance with Special Condition S4.D.5.b of the CSWGP, the Ecology Regional office will be notified if chemical treatment other than CO2 sparging is planned for adjustment of high pH water. 132 of 347 21-3259 Page 32 Garden Avenue Realingment March 2023 CP-2022 | City of Auburn Appendix/Glossary A. Site Map The site map must meet the requirements of Special Condition S9.E of the CSWGP B. BMP Detail Insert BMPs specification sheets here. Download BMPs from the Ecology Construction Stormwater website at: https://www.ecology.wa.gov/Regulations-Permits/Guidance-technical- assistance/Stormwater-permittee-guidance-resources/Stormwater-manuals C. Correspondence Ecology EPA Local Government D. Site Inspection Form Create your own or download Ecology’s template: https://www.ecology.wa.gov/Regulations-Permits/Permits-certifications/Stormwater- general-permits/Construction-stormwater-permit E. Construction Stormwater General Permit (CSWGP) F. Engineering Calculations 133 of 347 Issuance Date: November 18, 2020 Effective Date: January 1, 2021 Expiration Date: December 31, 2025 CONSTRUCTION STORMWATER GENERAL PERMIT National Pollutant Discharge Elimination System (NPDES) and State Waste Discharge General Permit for Stormwater Discharges Associated with Construction Activity State of Washington Department of Ecology Olympia, Washington 98504 In compliance with the provisions of Chapter 90.48 Revised Code of Washington (State of Washington Water Pollution Control Act) and Title 33 United States Code, Section 1251 et seq. The Federal Water Pollution Control Act (The Clean Water Act) Until this permit expires, is modified, or revoked, Permittees that have properly obtained coverage under this general permit are authorized to discharge in accordance with the special and general conditions that follow. __________________________________ Vincent McGowan, P.E. Water Quality Program Manager Washington State Department of Ecology 134 of 347 TABLE OF CONTENTS LIST OF TABLES .................................................................................................................................. ii SUMMARY OF PERMIT REPORT SUBMITTALS ...................................................................................... 1 SPECIAL CONDITIONS ......................................................................................................................... 3 S1. Permit Coverage .............................................................................................................................. 3 S2. Application Requirements ............................................................................................................... 7 S3. Compliance with Standards ............................................................................................................. 9 S4. Monitoring Requirements, Benchmarks, and Reporting Triggers ................................................. 10 S5. Reporting and Recordkeeping Requirements ................................................................................ 17 S6. Permit Fees .................................................................................................................................... 20 S7. Solid and Liquid Waste Disposal .................................................................................................... 20 S8. Discharges to 303(D) or TMDL Waterbodies ................................................................................. 20 S9. Stormwater Pollution Prevention Plan .......................................................................................... 23 S10. Notice Of Termination ................................................................................................................... 32 GENERAL CONDITIONS ..................................................................................................................... 34 G1. Discharge Violations....................................................................................................................... 34 G2. Signatory Requirements ................................................................................................................ 34 G3. Right of Inspection and Entry ......................................................................................................... 35 G4. General Permit Modification and Revocation ............................................................................... 35 G5. Revocation of Coverage Under tPermit ......................................................................................... 35 G6. Reporting a Cause for Modification ............................................................................................... 36 G7. Compliance with Other Laws and Statutes .................................................................................... 36 G8. Duty to Reapply.............................................................................................................................. 36 G9. Removed Substance ....................................................................................................................... 36 G10. Duty to Provide Information .......................................................................................................... 36 G11. Other Requirements of 40 CFR ...................................................................................................... 37 G12. Additional Monitoring .................................................................................................................... 37 G13. Penalties for Violating Permit Conditions ...................................................................................... 37 G14. Upset .............................................................................................................................................. 37 G15. Property Rights .............................................................................................................................. 37 G16. Duty to Comply .............................................................................................................................. 37 G17. Toxic Pollutants .............................................................................................................................. 38 G18. Penalties for Tampering ................................................................................................................. 38 G19. Reporting Planned Changes ........................................................................................................... 38 G20. Reporting Other Information ......................................................................................................... 38 G21. Reporting Anticipated Non-Compliance ........................................................................................ 38 135 of 347 G22. Requests to Be Excluded From Coverage Under the Permit ......................................................... 39 G23. Appeals........................................................................................................................................... 39 G24. Severability..................................................................................................................................... 39 G25. Bypass Prohibited .......................................................................................................................... 39 APPENDIX A – DEFINITIONS .............................................................................................................. 42 APPENDIX B – ACRONYMS ................................................................................................................ 50 LIST OF TABLES Table 1 Summary of Required Submittals ................................................................................................ 1 Table 2 Summary of Required On-site Documentation ........................................................................... 2 Table 3 Summary of Primary Monitoring Requirements ....................................................................... 12 Table 4 Monitoring and Reporting Requirements ................................................................................. 14 Table 5 Turbidity, Fine Sediment & Phosphorus Sampling and Limits for 303(d)-Listed Waters ................................................................................................................ 22 Table 6 pH Sampling and Limits for 303(d)-Listed Waters ..................................................................... 22 136 of 347 SUMMARY OF PERMIT REPORT SUBMITTALS Refer to the Special and General Conditions within this permit for additional submittal requirements. Appendix A provides a list of definitions. Appendix B provides a list of acronyms. Table 1 Summary of Required Submittals Permit Section Submittal Frequency First Submittal Date S5.A and S8 High Turbidity/Transparency Phone Reporting As Necessary Within 24 hours S5.B Discharge Monitoring Report Monthly* Within 15 days following the end of each month S5.F and S8 Noncompliance Notification – Telephone Notification As necessary Within 24 hours S5.F Noncompliance Notification – Written Report As necessary Within 5 Days of non-compliance S9.D Request for Chemical Treatment Form As necessary Written approval from Ecology is required prior to using chemical treatment (with the exception of dry ice, CO2 or food grade vinegar to adjust pH) G2 Notice of Change in Authorization As necessary G6 Permit Application for Substantive Changes to the Discharge As necessary G8 Application for Permit Renewal 1/permit cycle No later than 180 days before expiration S2.A Notice of Permit Transfer As necessary G19 Notice of Planned Changes As necessary G21 Reporting Anticipated Non-compliance As necessary NOTE: *Permittees must submit electronic Discharge Monitoring Reports (DMRs) to the Washington State Department of Ecology monthly, regardless of site discharge, for the full duration of permit coverage. Refer to Section S5.B of this General Permit for more specific information regarding DMRs. 137 of 347 Table 2 Summary of Required On-site Documentation Document Title Permit Conditions Permit Coverage Letter See Conditions S2, S5 Construction Stormwater General Permit (CSWGP) See Conditions S2, S5 Site Log Book See Conditions S4, S5 Stormwater Pollution Prevention Plan (SWPPP) See Conditions S5, S9 Site Map See Conditions S5, S9 138 of 347 SPECIAL CONDITIONS S1. PERMIT COVERAGE A.Permit Area This Construction Stormwater General Permit (CSWGP) covers all areas of Washington State, except for federal operators and Indian Country as specified in Special Condition S1.E.3 and 4. B.Operators Required to Seek Coverage Under this General Permit 1.Operators of the following construction activities are required to seek coverage under this CSWGP: a.Clearing, grading and/or excavation that results in the disturbance of one or more acres (including off-site disturbance acreage related to construction-support activity as authorized in S1.C.2) and discharges stormwater to surface waters of the State; and clearing, grading and/or excavation on sites smaller than one acre that are part of a larger common plan of development or sale, if the common plan of development or sale will ultimately disturb one acre or more and discharge stormwater to surface waters of the State. i.This category includes forest practices (including, but not limited to, class IV conversions) that are part of a construction activity that will result in the disturbance of one or more acres, and discharge to surface waters of the State (that is, forest practices that prepare a site for construction activities); and b.Any size construction activity discharging stormwater to waters of the State that the Washington State Department of Ecology (Ecology): i.Determines to be a significant contributor of pollutants to waters of the State of Washington. ii.Reasonably expects to cause a violation of any water quality standard. 2.Operators of the following activities are not required to seek coverage under this CSWGP (unless specifically required under Special Condition S1.B.1.b, above): a.Construction activities that discharge all stormwater and non-stormwater to groundwater, sanitary sewer, or combined sewer, and have no point source discharge to either surface water or a storm sewer system that drains to surface waters of the State. b.Construction activities covered under an Erosivity Waiver (Special Condition S1.F). c.Routine maintenance that is performed to maintain the original line and grade, hydraulic capacity, or original purpose of a facility. C.Authorized Discharges 1.Stormwater Associated with Construction Activity. Subject to compliance with the terms and conditions of this permit, Permittees are authorized to discharge stormwater associated with construction activity to surface waters of the State or to a storm sewer system that drains to surface waters of the State. (Note that “surface waters of the 139 of 347 State” may exist on a construction site as well as off site; for example, a creek running through a site.) 2. Stormwater Associated with Construction Support Activity. This permit also authorizes stormwater discharge from support activities related to the permitted construction site (for example, an on-site portable rock crusher, off-site equipment staging yards, material storage areas, borrow areas, etc.) provided: a. The support activity relates directly to the permitted construction site that is required to have an NPDES permit; and b. The support activity is not a commercial operation serving multiple unrelated construction projects, and does not operate beyond the completion of the construction activity; and c. Appropriate controls and measures are identified in the Stormwater Pollution Prevention Plan (SWPPP) for the discharges from the support activity areas. 3. Non-Stormwater Discharges. The categories and sources of non-stormwater discharges identified below are authorized conditionally, provided the discharge is consistent with the terms and conditions of this permit: a. Discharges from fire-fighting activities. b. Fire hydrant system flushing. c. Potable water, including uncontaminated water line flushing. d. Hydrostatic test water. e. Uncontaminated air conditioning or compressor condensate. f. Uncontaminated groundwater or spring water. g. Uncontaminated excavation dewatering water (in accordance with S9.D.10). h. Uncontaminated discharges from foundation or footing drains. i. Uncontaminated or potable water used to control dust. Permittees must minimize the amount of dust control water used. j. Routine external building wash down that does not use detergents. k. Landscape irrigation water. The SWPPP must adequately address all authorized non-stormwater discharges, except for discharges from fire-fighting activities, and must comply with Special Condition S3. At a minimum, discharges from potable water (including water line flushing), fire hydrant system flushing, and pipeline hydrostatic test water must undergo the following: dechlorination to a concentration of 0.1 parts per million (ppm) or less, and pH adjustment to within 6.5 – 8.5 standard units (su), if necessary. D. Prohibited Discharges The following discharges to waters of the State, including groundwater, are prohibited: 140 of 347 1. Concrete wastewater 2. Wastewater from washout and clean-up of stucco, paint, form release oils, curing compounds and other construction materials. 3. Process wastewater as defined by 40 Code of Federal Regulations (CFR) 122.2 (See Appendix A of this permit). 4. Slurry materials and waste from shaft drilling, including process wastewater from shaft drilling for construction of building, road, and bridge foundations unless managed according to Special Condition S9.D.9.j. 5. Fuels, oils, or other pollutants used in vehicle and equipment operation and maintenance. 6. Soaps or solvents used in vehicle and equipment washing. 7. Wheel wash wastewater, unless managed according to Special Condition S9.D.9. 8. Discharges from dewatering activities, including discharges from dewatering of trenches and excavations, unless managed according to Special Condition S9.D.10. E. Limits on Coverage Ecology may require any discharger to apply for and obtain coverage under an individual permit or another more specific general permit. Such alternative coverage will be required when Ecology determines that this CSWGP does not provide adequate assurance that water quality will be protected, or there is a reasonable potential for the project to cause or contribute to a violation of water quality standards. The following stormwater discharges are not covered by this permit: 1. Post-construction stormwater discharges that originate from the site after completion of construction activities and the site has undergone final stabilization. 2. Non-point source silvicultural activities such as nursery operations, site preparation, reforestation and subsequent cultural treatment, thinning, prescribed burning, pest and fire control, harvesting operations, surface drainage, or road construction and maintenance, from which there is natural runoff as excluded in 40 CFR Subpart 122. 3. Stormwater from any federal operator. 4. Stormwater from facilities located on Indian Country as defined in 18 U.S.C.§1151, except portions of the Puyallup Reservation as noted below. Indian Country includes: a. All land within any Indian Reservation notwithstanding the issuance of any patent, and, including rights-of-way running through the reservation. This includes all federal, tribal, and Indian and non-Indian privately owned land within the reservation. b. All off-reservation Indian allotments, the Indian titles to which have not been extinguished, including rights-of-way running through the same. c. All off-reservation federal trust lands held for Native American Tribes. 141 of 347 Puyallup Exception: Following the Puyallup Tribes of Indians Land Settlement Act of 1989, 25 U.S.C. §1773; the permit does apply to land within the Puyallup Reservation except for discharges to surface water on land held in trust by the federal government. 5. Stormwater from any site covered under an existing NPDES individual permit in which stormwater management and/or treatment requirements are included for all stormwater discharges associated with construction activity. 6. Stormwater from a site where an applicable Total Maximum Daily Load (TMDL) requirement specifically precludes or prohibits discharges from construction activity. F. Erosivity Waiver Construction site operators may qualify for an Erosivity Waiver from the CSWGP if the following conditions are met: 1. The site will result in the disturbance of fewer than five (5) acres and the site is not a portion of a common plan of development or sale that will disturb five (5) acres or greater. 2. Calculation of Erosivity “R” Factor and Regional Timeframe: a. The project’s calculated rainfall erosivity factor (“R” Factor) must be less than five (5) during the period of construction activity, (See the CSWGP homepage http://www.ecy.wa.gov/programs/wq/stormwater/construction/index.html for a link to the EPA’s calculator and step by step instructions on computing the “R” Factor in the EPA Erosivity Waiver Fact Sheet). The period of construction activity starts when the land is first disturbed and ends with final stabilization. In addition: b. The entire period of construction activity must fall within the following timeframes: i. For sites west of the Cascades Crest: June 15 – September 15. ii. For sites east of the Cascades Crest, excluding the Central Basin: June 15 – October 15. iii. For sites east of the Cascades Crest, within the Central Basin: no timeframe restrictions apply. The Central Basin is defined as the portions of Eastern Washington with mean annual precipitation of less than 12 inches. For a map of the Central Basin (Average Annual Precipitation Region 2), refer to: http://www.ecy.wa.gov/programs/wq/stormwater/construction/resourcesguida nce.html. 3. Construction site operators must submit a complete Erosivity Waiver certification form at least one week before disturbing the land. Certification must include statements that the operator will: a. Comply with applicable local stormwater requirements; and b. Implement appropriate erosion and sediment control BMPs to prevent violations of water quality standards. 4. This waiver is not available for facilities declared significant contributors of pollutants as defined in Special Condition S1.B.1.b or for any size construction activity that could 142 of 347 reasonably expect to cause a violation of any water quality standard as defined in Special Condition S1.B.1.b.ii. 5. This waiver does not apply to construction activities which include non-stormwater discharges listed in Special Condition S1.C.3. 6. If construction activity extends beyond the certified waiver period for any reason, the operator must either: a. Recalculate the rainfall erosivity “R” factor using the original start date and a new projected ending date and, if the “R” factor is still under 5 and the entire project falls within the applicable regional timeframe in Special Condition S1.F.2.b, complete and submit an amended waiver certification form before the original waiver expires; or b. Submit a complete permit application to Ecology in accordance with Special Condition S2.A and B before the end of the certified waiver period. S2. APPLICATION REQUIREMENTS A. Permit Application Forms 1. Notice of Intent Form a. Operators of new or previously unpermitted construction activities must submit a complete and accurate permit application (Notice of Intent, or NOI) to Ecology. b. Operators must apply using the electronic application form (NOI) available on Ecology’s website (http://ecy.wa.gov/programs/wq/stormwater/construction/index.html). Permittees unable to submit electronically (for example, those who do not have an internet connection) must contact Ecology to request a waiver and obtain instructions on how to obtain a paper NOI. Department of Ecology Water Quality Program - Construction Stormwater PO Box 47696 Olympia, Washington 98504-7696 c. The operator must submit the NOI at least 60 days before discharging stormwater from construction activities and must submit it prior to the date of the first public notice (See Special Condition S2.B, below, for details). The 30-day public comment period begins on the publication date of the second public notice. Unless Ecology responds to the complete application in writing, coverage under the general permit will automatically commence on the 31st day following receipt by Ecology of a completed NOI, or the issuance date of this permit, whichever is later; unless Ecology specifies a later date in writing as required by WAC173-226-200(2). See S8.B for Limits on Coverage for New Discharges to TMDL or 303(d)-Listed Waters. d. If an applicant intends to use a Best Management Practice (BMP) selected on the basis of Special Condition S9.C.4 (“demonstrably equivalent” BMPs), the applicant must notify Ecology of its selection as part of the NOI. In the event the applicant selects BMPs after submission of the NOI, the applicant must provide notice of the 143 of 347 selection of an equivalent BMP to Ecology at least 60 days before intended use of the equivalent BMP. e. Applicants must notify Ecology if they are aware of contaminated soils and/or groundwater associated with the construction activity. Provide detailed information with the NOI (as known and readily available) on the nature and extent of the contamination (concentrations, locations, and depth), as well as pollution prevention and/or treatment BMPs proposed to control the discharge of soil and/or groundwater contaminants in stormwater. Examples of such detail may include, but are not limited to: i. List or table of all known contaminants with laboratory test results showing concentration and depth, ii. Map with sample locations, iii. Related portions of the Stormwater Pollution Prevention Plan (SWPPP) that address the management of contaminated and potentially contaminated construction stormwater and dewatering water, iv. Dewatering plan and/or dewatering contingency plan. 2. Transfer of Coverage Form The Permittee can transfer current coverage under this permit to one or more new operators, including operators of sites within a Common Plan of Development, provided: i. The Permittee submits a complete Transfer of Coverage Form to Ecology, signed by the current and new discharger and containing a specific date for transfer of permit responsibility, coverage and liability (including any Administrative Orders associated with the permit); and ii. Ecology does not notify the current discharger and new discharger of intent to revoke coverage under the general permit. If this notice is not given, the transfer is effective on the date specified in the written agreement. When a current discharger (Permittee) transfers a portion of a permitted site, the current discharger must also indicate the remaining permitted acreage after the transfer. Transfers do not require public notice. 3. Modification of Coverage Form Permittees must notify Ecology regarding any changes to the information provided on the NOI by submitting an Update/Modification of Permit Coverage form in accordance with General Conditions G6 and G19. Examples of such changes include, but are not limited to: i. Changes to the Permittee’s mailing address, ii. Changes to the on-site contact person information, and iii. Changes to the area/acreage affected by construction activity. 144 of 347 B. Public Notice For new or previously unpermitted construction activities, the applicant must publish a public notice at least one time each week for two consecutive weeks, at least 7 days apart, in a newspaper with general circulation in the county where the construction is to take place. The notice must be run after the NOI has been submitted and must contain: 1. A statement that “The applicant is seeking coverage under the Washington State Department of Ecology’s Construction Stormwater NPDES and State Waste Discharge General Permit.” 2. The name, address, and location of the construction site. 3. The name and address of the applicant. 4. The type of construction activity that will result in a discharge (for example, residential construction, commercial construction, etc.), and the total number of acres to be disturbed over the lifetime of the project. 5. The name of the receiving water(s) (that is, the surface water(s) to which the site will discharge), or, if the discharge is through a storm sewer system, the name of the operator of the system and the receiving water(s) the system discharges to. 6. The statement: Any persons desiring to present their views to the Washington State Department of Ecology regarding this application, or interested in Ecology’s action on this application, may notify Ecology in writing no later than 30 days of the last date of publication of this notice. Ecology reviews public comments and considers whether discharges from this project would cause a measurable change in receiving water quality, and, if so, whether the project is necessary and in the overriding public interest according to Tier II antidegradation requirements under WAC 173-201A-320. Comments can be submitted to: Department of Ecology, PO Box 47696, Olympia, Washington 98504-7696 Attn: Water Quality Program, Construction Stormwater. S3. COMPLIANCE WITH STANDARDS A. Discharges must not cause or contribute to a violation of surface water quality standards (Chapter 173-201A WAC), groundwater quality standards (Chapter 173-200 WAC), sediment management standards (Chapter 173-204 WAC), and human health-based criteria in the Federal water quality criteria applicable to Washington. (40 CFR Part 131.45) Discharges that are not in compliance with these standards are prohibited. B. Prior to the discharge of stormwater and non-stormwater to waters of the State, the Permittee must apply All Known, Available, and Reasonable methods of prevention, control, and Treatment (AKART). This includes the preparation and implementation of an adequate SWPPP, with all appropriate BMPs installed and maintained in accordance with the SWPPP and the terms and conditions of this permit. C. Ecology presumes that a Permittee complies with water quality standards unless discharge monitoring data or other site-specific information demonstrates that a discharge causes or contributes to a violation of water quality standards, when the Permittee complies with the following conditions. The Permittee must fully: 145 of 347 1. Comply with all permit conditions, including; planning, sampling, monitoring, reporting, and recordkeeping conditions. 2. Implement stormwater BMPs contained in stormwater management manuals published or approved by Ecology, or BMPs that are demonstrably equivalent to BMPs contained in stormwater management manuals published or approved by Ecology, including the proper selection, implementation, and maintenance of all applicable and appropriate BMPs for on-site pollution control. (For purposes of this section, the stormwater manuals listed in Appendix 10 of the Phase I Municipal Stormwater Permit are approved by Ecology.) D. Where construction sites also discharge to groundwater, the groundwater discharges must also meet the terms and conditions of this CSWGP. Permittees who discharge to groundwater through an injection well must also comply with any applicable requirements of the Underground Injection Control (UIC) regulations, Chapter 173-218 WAC. S4. MONITORING REQUIREMENTS, BENCHMARKS, AND REPORTING TRIGGERS A. Site Log Book The Permittee must maintain a site log book that contains a record of the implementation of the SWPPP and other permit requirements, including the installation and maintenance of BMPs, site inspections, and stormwater monitoring. B. Site Inspections Construction sites one (1) acre or larger that discharge stormwater to surface waters of the State must have site inspections conducted by a Certified Erosion and Sediment Control Lead (CESCL). Sites less than one (1) acre may have a person without CESCL certification conduct inspections. (See Special Conditions S4.B.3 and B.4, below, for detailed requirements of the Permittee’s CESCL.) Site inspections must include all areas disturbed by construction activities, all BMPs, and all stormwater discharge points under the Permittee’s operational control. 1. The Permittee must have staff knowledgeable in the principles and practices of erosion and sediment control. The CESCL (sites one acre or more) or inspector (sites less than one acre) must have the skills to assess the: a. Site conditions and construction activities that could impact the quality of stormwater; and b. Effectiveness of erosion and sediment control measures used to control the quality of stormwater discharges. The SWPPP must identify the CESCL or inspector, who must be present on site or on-call at all times. The CESCL (sites one (1) acre or more) must obtain this certification through an approved erosion and sediment control training program that meets the minimum training standards established by Ecology. (See BMP C160 in the manual, referred to in Special Condition S9.C.1 and 2.) 2. The CESCL or inspector must examine stormwater visually for the presence of suspended sediment, turbidity, discoloration, and oil sheen. BMP effectiveness must be evaluated to 146 of 347 determine if it is necessary to install, maintain, or repair BMPs to improve the quality of stormwater discharges. Based on the results of the inspection, the Permittee must correct the problems identified, by: a. Reviewing the SWPPP for compliance with Special Condition S9 and making appropriate revisions within 7 days of the inspection. b. Immediately beginning the process of fully implementing and maintaining appropriate source control and/or treatment BMPs, within 10 days of the inspection. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when an extension is requested by a Permittee within the initial 10-day response period. c. Documenting BMP implementation and maintenance in the site log book. 3. The CESCL or inspector must inspect all areas disturbed by construction activities, all BMPs, and all stormwater discharge points at least once every calendar week and within 24 hours of any discharge from the site. (For purposes of this condition, individual discharge events that last more than one (1) day do not require daily inspections. For example, if a stormwater pond discharges continuously over the course of a week, only one (1) inspection is required that week.) Inspection frequency may be reduced to once every calendar month for inactive sites that are temporarily stabilized. 4. The Permittee must summarize the results of each inspection in an inspection report or checklist and enter the report/checklist into, or attach it to, the site log book. At a minimum, each inspection report or checklist must include: a. Inspection date and time. b. Weather information. c. The general conditions during inspection. d. The approximate amount of precipitation since the last inspection. e. The approximate amount of precipitation within the last 24 hours. f. A summary or list of all implemented BMPs, including observations of all erosion/sediment control structures or practices. g. A description of: i. BMPs inspected (including location). ii. BMPs that need maintenance and why. iii. BMPs that failed to operate as designed or intended, and iv. Where additional or different BMPs are needed, and why. h. A description of stormwater discharged from the site. The Permittee must note the presence of suspended sediment, turbidity, discoloration, and oil sheen, as applicable. 147 of 347 i. Any water quality monitoring performed during inspection. j. General comments and notes, including a brief description of any BMP repairs, maintenance, or installations made following the inspection. k. An implementation schedule for the remedial actions that the Permittee plans to take if the site inspection indicates that the site is out of compliance. The remedial actions taken must meet the requirements of the SWPPP and the permit. l. A summary report of the inspection. m. The name, title, and signature of the person conducting the site inspection, a phone number or other reliable method to reach this person, and the following statement: I certify that this report is true, accurate, and complete to the best of my knowledge and belief. Table 3 Summary of Primary Monitoring Requirements Size of Soil Disturbance 1 Weekly Site Inspections Weekly Sampling w/ Turbidity Meter Weekly Sampling w/ Transparency Tube Weekly pH Sampling 2 CESCL Required for Inspections? Sites that disturb less than 1 acre, but are part of a larger Common Plan of Development Required Not Required Not Required Not Required No Sites that disturb 1 acre or more, but fewer than 5 acres Required Sampling Required – either method 3 Required Yes Sites that disturb 5 acres or more Required Required Not Required 4 Required Yes 1 Soil disturbance is calculated by adding together all areas that will be affected by construction activity. Construction activity means clearing, grading, excavation, and any other activity that disturbs the surface of the land, including ingress/egress from the site. 2 If construction activity results in the disturbance of 1 acre or more, and involves significant concrete work (1,000 cubic yards of concrete or recycled concrete placed or poured over the life of a project) or the use of engineered soils (soil amendments including but not limited to Portland cement-treated base [CTB], cement kiln dust [CKD], or fly ash), and stormwater from the affected area drains to surface waters of the State or to a storm sewer stormwater collection system that drains to other surface waters of the State, the Permittee must conduct pH sampling in accordance with Special Condition S4.D. 3 Sites with one or more acres, but fewer than 5 acres of soil disturbance, must conduct turbidity or transparency sampling in accordance with Special Condition S4.C.4.a or b. 4 Sites equal to or greater than 5 acres of soil disturbance must conduct turbidity sampling using a turbidity meter in accordance with Special Condition S4.C.4.a. 148 of 347 C. Turbidity/Transparency Sampling Requirements 1. Sampling Methods a. If construction activity involves the disturbance of five (5) acres or more, the Permittee must conduct turbidity sampling per Special Condition S4.C.4.a, below. b. If construction activity involves one (1) acre or more but fewer than five (5) acres of soil disturbance, the Permittee must conduct either transparency sampling or turbidity sampling per Special Condition S4.C.4.a or b, below. 2. Sampling Frequency a. The Permittee must sample all discharge points at least once every calendar week when stormwater (or authorized non-stormwater) discharges from the site or enters any on-site surface waters of the state (for example, a creek running through a site); sampling is not required on sites that disturb less than an acre. b. Samples must be representative of the flow and characteristics of the discharge. c. Sampling is not required when there is no discharge during a calendar week. d. Sampling is not required outside of normal working hours or during unsafe conditions. e. If the Permittee is unable to sample during a monitoring period, the Permittee must include a brief explanation in the monthly Discharge Monitoring Report (DMR). f. Sampling is not required before construction activity begins. g. The Permittee may reduce the sampling frequency for temporarily stabilized, inactive sites to once every calendar month. 3. Sampling Locations a. Sampling is required at all points where stormwater associated with construction activity (or authorized non-stormwater) is discharged off site, including where it enters any on-site surface waters of the state (for example, a creek running through a site). b. The Permittee may discontinue sampling at discharge points that drain areas of the project that are fully stabilized to prevent erosion. c. The Permittee must identify all sampling point(s) in the SWPPP and on the site map and clearly mark these points in the field with a flag, tape, stake or other visible marker. d. Sampling is not required for discharge that is sent directly to sanitary or combined sewer systems. e. The Permittee may discontinue sampling at discharge points in areas of the project where the Permittee no longer has operational control of the construction activity. 149 of 347 4. Sampling and Analysis Methods a. The Permittee performs turbidity analysis with a calibrated turbidity meter (turbidimeter) either on site or at an accredited lab. The Permittee must record the results in the site log book in nephelometric turbidity units (NTUs). b. The Permittee performs transparency analysis on site with a 1¾ inch diameter, 60 centimeter (cm)-long transparency tube. The Permittee will record the results in the site log book in centimeters (cm). Table 4 Monitoring and Reporting Requirements Parameter Unit Analytical Method Sampling Frequency Benchmark Value Turbidity NTU SM2130 Weekly, if discharging 25 NTUs Transparency Cm Manufacturer instructions, or Ecology guidance Weekly, if discharging 33 cm 5. Turbidity/Transparency Benchmark Values and Reporting Triggers The benchmark value for turbidity is 25 NTUs. The benchmark value for transparency is 33 centimeters (cm). Note: Benchmark values do not apply to discharges to segments of water bodies on Washington State’s 303(d) list (Category 5) for turbidity, fine sediment, or phosphorus; these discharges are subject to a numeric effluent limit for turbidity. Refer to Special Condition S8 for more information and follow S5.F – Noncompliance Notification for reporting requirements applicable to discharges which exceed the numeric effluent limit for turbidity. a. Turbidity 26 – 249 NTUs, or Transparency 32 – 7 cm: If the discharge turbidity is 26 to 249 NTUs; or if discharge transparency is 32 to 7 cm, the Permittee must: i. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs, and no later than 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period. ii. Review the SWPPP for compliance with Special Condition S9 and make appropriate revisions within 7 days of the date the discharge exceeded the benchmark. iii. Document BMP implementation and maintenance in the site log book. b. Turbidity 250 NTUs or greater, or Transparency 6 cm or less: If a discharge point’s turbidity is 250 NTUs or greater, or if discharge transparency is less than or equal to 6 cm, the Permittee must complete the reporting and adaptive 150 of 347 management process described below. For discharges which are subject to a numeric effluent limit for turbidity, see S5.F – Noncompliance Notification. i. Within 24 hours, telephone or submit an electronic report to the applicable Ecology Region’s Environmental Report Tracking System (ERTS) number (or through Ecology’s Water Quality Permitting Portal [WQWebPortal] – Permit Submittals when the form is available), in accordance with Special Condition S5.A. • Central Region (Okanogan, Chelan, Douglas, Kittitas, Yakima, Klickitat, Benton): (509) 575-2490 • Eastern Region (Adams, Asotin, Columbia, Ferry, Franklin, Garfield, Grant, Lincoln, Pend Oreille, Spokane, Stevens, Walla Walla, Whitman): (509) 329-3400 • Northwest Region (Kitsap, Snohomish, Island, King, San Juan, Skagit, Whatcom): (425) 649-7000 • Southwest Region (Grays Harbor, Lewis, Mason, Thurston, Pierce, Clark, Cowlitz, Skamania, Wahkiakum, Clallam, Jefferson, Pacific): (360) 407-6300 These numbers and a link to the ERTS reporting page are also listed at the following website: http://www.ecy.wa.gov/programs/wq/stormwater/construction/index.html. ii. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible, addressing the problems within 10 days of the date the discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when the Permittee requests an extension within the initial 10-day response period. iii. Sample discharges daily until: a) Turbidity is 25 NTUs (or lower); or b) Transparency is 33 cm (or greater); or c) The Permittee has demonstrated compliance with the water quality standard for turbidity: 1) No more than 5 NTUs over background turbidity, if background is less than 50 NTUs, or 2) No more than 10% over background turbidity, if background is 50 NTUs or greater; or *Note: background turbidity in the receiving water must be measured immediately upstream (upgradient) or outside of the area of influence of the discharge. d) The discharge stops or is eliminated. iv. Review the SWPPP for compliance with Special Condition S9 and make appropriate revisions within seven (7) days of the date the discharge exceeded the benchmark. 151 of 347 v. Document BMP implementation and maintenance in the site log book. Compliance with these requirements does not relieve the Permittee from responsibility to maintain continuous compliance with permit benchmarks. D. pH Sampling Requirements – Significant Concrete Work or Engineered Soils If construction activity results in the disturbance of 1 acre or more, and involves significant concrete work (significant concrete work means greater than 1000 cubic yards placed or poured concrete or recycled concrete used over the life of a project) or the use of engineered soils (soil amendments including but not limited to Portland cement-treated base [CTB], cement kiln dust [CKD], or fly ash), and stormwater from the affected area drains to surface waters of the State or to a storm sewer system that drains to surface waters of the State, the Permittee must conduct pH sampling as set forth below. Note: In addition, discharges to segments of water bodies on Washington State’s 303(d) list (Category 5) for high pH are subject to a numeric effluent limit for pH; refer to Special Condition S8. 1. The Permittee must perform pH analysis on site with a calibrated pH meter, pH test kit, or wide range pH indicator paper. The Permittee must record pH sampling results in the site log book. 2. During the applicable pH monitoring period defined below, the Permittee must obtain a representative sample of stormwater and conduct pH analysis at least once per week. a. For sites with significant concrete work, the Permittee must begin the pH sampling period when the concrete is first placed or poured and exposed to precipitation, and continue weekly throughout and after the concrete placement, pour and curing period, until stormwater pH is in the range of 6.5 to 8.5 (su). b. For sites with recycled concrete where monitoring is required, the Permittee must begin the weekly pH sampling period when the recycled concrete is first exposed to precipitation and must continue until the recycled concrete is fully stabilized with the stormwater pH in the range of 6.5 to 8.5 (su). c. For sites with engineered soils, the Permittee must begin the pH sampling period when the soil amendments are first exposed to precipitation and must continue until the area of engineered soils is fully stabilized. 3. The Permittee must sample pH in the sediment trap/pond(s) or other locations that receive stormwater runoff from the area of significant concrete work or engineered soils before the stormwater discharges to surface waters. 4. The benchmark value for pH is 8.5 standard units. Anytime sampling indicates that pH is 8.5 or greater, the Permittee must either: a. Prevent the high pH water (8.5 or above) from entering storm sewer systems or surface waters of the state; or b. If necessary, adjust or neutralize the high pH water until it is in the range of pH 6.5 to 8.5 (su) using an appropriate treatment BMP such as carbon dioxide (CO2) sparging, dry ice or food grade vinegar. The Permittee must obtain written approval from Ecology before using any form of chemical treatment other than CO2 sparging, dry ice or food grade vinegar. 152 of 347 S5. REPORTING AND RECORDKEEPING REQUIREMENTS A. High Turbidity Reporting Anytime sampling performed in accordance with Special Condition S4.C indicates turbidity has reached the 250 NTUs or more (or transparency less than or equal to 6 cm), high turbidity reporting level, the Permittee must notify Ecology within 24 hours of analysis either by calling the applicable Ecology Region’s Environmental Report Tracking System (ERTS) number by phone or by submitting an electronic ERTS report (through Ecology’s Water Quality Permitting Portal (WQWebPortal) – Permit Submittals when the form is available). See the CSWGP website for links to ERTS and the WQWebPortal. (http://www.ecy.wa.gov/programs/wq/stormwater/ construction/index.html) Also, see phone numbers in Special Condition S4.C.5.b.i. B. Discharge Monitoring Reports (DMRs) Permittees required to conduct water quality sampling in accordance with Special Conditions S4.C (Turbidity/Transparency), S4.D (pH), S8 (303[d]/TMDL sampling), and/or G12 (Additional Sampling) must submit the results to Ecology. Permittees must submit monitoring data using Ecology's WQWebDMR web application accessed through Ecology’s Water Quality Permitting Portal. Permittees unable to submit electronically (for example, those who do not have an internet connection) must contact Ecology to request a waiver and obtain instructions on how to obtain a paper copy DMR at: Department of Ecology Water Quality Program - Construction Stormwater PO Box 47696 Olympia, WA 98504-7696 Permittees who obtain a waiver not to use WQWebDMR must use the forms provided to them by Ecology; submittals must be mailed to the address above. Permittees must submit DMR forms to be received by Ecology within 15 days following the end of each month. If there was no discharge during a given monitoring period, all Permittees must submit a DMR as required with “no discharge” entered in place of the monitoring results. DMRs are required for the full duration of permit coverage (from the first full month following the effective date of permit coverage up until Ecology has approved termination of the coverage). For more information, contact Ecology staff using information provided at the following website: www.ecy.wa.gov/programs/wq/permits/paris/contacts.html. C. Records Retention The Permittee must retain records of all monitoring information (site log book, sampling results, inspection reports/checklists, etc.), Stormwater Pollution Prevention Plan, copy of the permit coverage letter (including Transfer of Coverage documentation) and any other documentation of compliance with permit requirements for the entire life of the construction project and for a minimum of five (5) years following the termination of permit coverage. Such information must include all calibration and maintenance records, and records of all data used to complete the application for this permit. This period of retention must be extended during 153 of 347 the course of any unresolved litigation regarding the discharge of pollutants by the Permittee or when requested by Ecology. D. Recording Results For each measurement or sample taken, the Permittee must record the following information: 1. Date, place, method, and time of sampling or measurement. 2. The first and last name of the individual who performed the sampling or measurement. 3. The date(s) the analyses were performed. 4. The first and last name of the individual who performed the analyses. 5. The analytical techniques or methods used. 6. The results of all analyses. E. Additional Monitoring by the Permittee If the Permittee samples or monitors any pollutant more frequently than required by this permit using test procedures specified by Special Condition S4 of this permit, the sampling results for this monitoring must be included in the calculation and reporting of the data submitted in the Permittee’s DMR. F. Noncompliance Notification In the event the Permittee is unable to comply with any part of the terms and conditions of this permit, and the resulting noncompliance may cause a threat to human health or the environment (such as but not limited to spills or fuels or other materials, catastrophic pond or slope failure, and discharges that violate water quality standards), or exceed numeric effluent limitations (see S8 – Discharges to 303(d) or TMDL Waterbodies), the Permittee must, upon becoming aware of the circumstance: 1. Notify Ecology within 24 hours of the failure to comply by calling the applicable Regional office ERTS phone number (refer to Special Condition S4.C.5.b.i, or go to https://ecology.wa.gov/About-us/Get-involved/Report-an-environmental-issue to find contact information for the regional offices.) 2. Immediately take action to prevent the discharge/pollution, or otherwise stop or correct the noncompliance, and, if applicable, repeat sampling and analysis of any noncompliance immediately and submit the results to Ecology within five (5) days of becoming aware of the violation (See S5.F.3, below, for details on submitting results in a report). 3. Submit a detailed written report to Ecology within five (5) days of the time the Permittee becomes aware of the circumstances, unless requested earlier by Ecology. The report must be submitted using Ecology’s Water Quality Permitting Portal (WQWebPortal) – Permit Submittals, unless a waiver from electronic reporting has been granted according to S5.B. The report must contain a description of the noncompliance, including exact dates and times, and if the noncompliance has not been corrected, the anticipated time it is expected to continue; and the steps taken or planned to reduce, eliminate, and prevent reoccurrence of the noncompliance. 154 of 347 The Permittee must report any unanticipated bypass and/or upset that exceeds any effluent limit in the permit in accordance with the 24-hour reporting requirement contained in 40 C.F.R. 122.41(l)(6). Compliance with these requirements does not relieve the Permittee from responsibility to maintain continuous compliance with the terms and conditions of this permit or the resulting liability for failure to comply. Upon request of the Permittee, Ecology may waive the requirement for a written report on a case-by-case basis, if the immediate notification is received by Ecology within 24 hours. G. Access to Plans and Records 1. The Permittee must retain the following permit documentation (plans and records) on site, or within reasonable access to the site, for use by the operator or for on-site review by Ecology or the local jurisdiction: a. General Permit b. Permit Coverage Letter c. Stormwater Pollution Prevention Plan (SWPPP) d. Site Log Book e. Erosivity Waiver (if applicable) 2. The Permittee must address written requests for plans and records listed above (Special Condition S5.G.1) as follows: a. The Permittee must provide a copy of plans and records to Ecology within 14 days of receipt of a written request from Ecology. b. The Permittee must provide a copy of plans and records to the public when requested in writing. Upon receiving a written request from the public for the Permittee’s plans and records, the Permittee must either: i. Provide a copy of the plans and records to the requester within 14 days of a receipt of the written request; or ii. Notify the requester within 10 days of receipt of the written request of the location and times within normal business hours when the plans and records may be viewed; and provide access to the plans and records within 14 days of receipt of the written request; or Within 14 days of receipt of the written request, the Permittee may submit a copy of the plans and records to Ecology for viewing and/or copying by the requester at an Ecology office, or a mutually agreed location. If plans and records are viewed and/or copied at a location other than at an Ecology office, the Permittee will provide reasonable access to copying services for which a reasonable fee may be charged. The Permittee must notify the requester within 10 days of receipt of the request where the plans and records may be viewed and/or copied. 155 of 347 S6. PERMIT FEES The Permittee must pay permit fees assessed by Ecology. Fees for stormwater discharges covered under this permit are established by Chapter 173-224 WAC. Ecology continues to assess permit fees until the permit is terminated in accordance with Special Condition S10 or revoked in accordance with General Condition G5. S7. SOLID AND LIQUID WASTE DISPOSAL The Permittee must handle and dispose of solid and liquid wastes generated by construction activity, such as demolition debris, construction materials, contaminated materials, and waste materials from maintenance activities, including liquids and solids from cleaning catch basins and other stormwater facilities, in accordance with: A. Special Condition S3, Compliance with Standards. B. WAC 173-216-110. C. Other applicable regulations. S8. DISCHARGES TO 303(d) OR TMDL WATERBODIES A. Sampling and Numeric Effluent Limits For Certain Discharges to 303(d)-Listed Water Bodies 1. Permittees who discharge to segments of water bodies listed as impaired by the State of Washington under Section 303(d) of the Clean Water Act for turbidity, fine sediment, high pH, or phosphorus, must conduct water quality sampling according to the requirements of this section, and Special Conditions S4.C.2.b-f and S4.C.3.b-d, and must comply with the applicable numeric effluent limitations in S8.C and S8.D. 2. All references and requirements associated with Section 303(d) of the Clean Water Act mean the most current listing by Ecology of impaired waters (Category 5) that exists on January 1, 2021, or the date when the operator’s complete permit application is received by Ecology, whichever is later. B. Limits on Coverage for New Discharges to TMDL or 303(d)-Listed Waters Construction sites that discharge to a TMDL or 303(d)-listed waterbody are not eligible for coverage under this permit unless the operator: 156 of 347 1. Prevents exposing stormwater to pollutants for which the waterbody is impaired, and retains documentation in the SWPPP that details procedures taken to prevent exposure on site; or 2. Documents that the pollutants for which the waterbody is impaired are not present at the site, and retains documentation of this finding within the SWPPP; or 3. Provides Ecology with data indicating the discharge is not expected to cause or contribute to an exceedance of a water quality standard, and retains such data on site with the SWPPP. The operator must provide data and other technical information to Ecology that sufficiently demonstrate: a. For discharges to waters without an EPA-approved or -established TMDL, that the discharge of the pollutant for which the water is impaired will meet in-stream water quality criteria at the point of discharge to the waterbody; or b. For discharges to waters with an EPA-approved or -established TMDL, that there is sufficient remaining wasteload allocation in the TMDL to allow construction stormwater discharge and that existing dischargers to the waterbody are subject to compliance schedules designed to bring the waterbody into attainment with water quality standards. Operators of construction sites are eligible for coverage under this permit only after Ecology makes an affirmative determination that the discharge will not cause or contribute to the existing impairment or exceed the TMDL. C. Sampling and Numeric Effluent Limits for Discharges to Water Bodies on the 303(d) List for Turbidity, Fine Sediment, or Phosphorus 1. Permittees who discharge to segments of water bodies on the 303(d) list (Category 5) for turbidity, fine sediment, or phosphorus must conduct turbidity sampling in accordance with Special Condition S4.C.2 and comply with either of the numeric effluent limits noted in Table 5 below. 2. As an alternative to the 25 NTUs effluent limit noted in Table 5 below (applied at the point where stormwater [or authorized non-stormwater] is discharged off-site), Permittees may choose to comply with the surface water quality standard for turbidity. The standard is: no more than 5 NTUs over background turbidity when the background turbidity is 50 NTUs or less, or no more than a 10% increase in turbidity when the background turbidity is more than 50 NTUs. In order to use the water quality standard requirement, the sampling must take place at the following locations: a. Background turbidity in the 303(d)-listed receiving water immediately upstream (upgradient) or outside the area of influence of the discharge. b. Turbidity at the point of discharge into the 303(d)-listed receiving water, inside the area of influence of the discharge. 3. Discharges that exceed the numeric effluent limit for turbidity constitute a violation of this permit. 4. Permittees whose discharges exceed the numeric effluent limit must sample discharges daily until the violation is corrected and comply with the non-compliance notification requirements in Special Condition S5.F. 157 of 347 Table 5 Turbidity, Fine Sediment & Phosphorus Sampling and Limits for 303(d)-Listed Waters Parameter identified in 303(d) listing Parameter Sampled Unit Analytical Method Sampling Frequency Numeric Effluent Limit1 • Turbidity • Fine Sediment • Phosphorus Turbidity NTU SM2130 Weekly, if discharging 25 NTUs, at the point where stormwater is discharged from the site; OR In compliance with the surface water quality standard for turbidity (S8.C.2.a) 1 Permittees subject to a numeric effluent limit for turbidity may, at their discretion, choose either numeric effluent limitation based on site-specific considerations including, but not limited to, safety, access and convenience. D. Discharges to Water Bodies on the 303(d) List for High pH 1. Permittees who discharge to segments of water bodies on the 303(d) list (Category 5) for high pH must conduct pH sampling in accordance with the table below, and comply with the numeric effluent limit of pH 6.5 to 8.5 su (Table 6). Table 6 pH Sampling and Limits for 303(d)-Listed Waters Parameter identified in 303(d) listing Parameter Sampled/Units Analytical Method Sampling Frequency Numeric Effluent Limit High pH pH /Standard Units pH meter Weekly, if discharging In the range of 6.5 – 8.5 su 2. At the Permittee’s discretion, compliance with the limit shall be assessed at one of the following locations: a. Directly in the 303(d)-listed waterbody segment, inside the immediate area of influence of the discharge; or b. Alternatively, the Permittee may measure pH at the point where the discharge leaves the construction site, rather than in the receiving water. 3. Discharges that exceed the numeric effluent limit for pH (outside the range of 6.5 – 8.5 su) constitute a violation of this permit. 4. Permittees whose discharges exceed the numeric effluent limit must sample discharges daily until the violation is corrected and comply with the non-compliance notification requirements in Special Condition S5.F. E. Sampling and Limits for Sites Discharging to Waters Covered by a TMDL or another Pollution Control Plan 158 of 347 1. Discharges to a waterbody that is subject to a Total Maximum Daily Load (TMDL) for turbidity, fine sediment, high pH, or phosphorus must be consistent with the TMDL. Refer to http://www.ecy.wa.gov/programs/wq/tmdl/TMDLsbyWria/TMDLbyWria.html for more information on TMDLs. a. Where an applicable TMDL sets specific waste load allocations or requirements for discharges covered by this permit, discharges must be consistent with any specific waste load allocations or requirements established by the applicable TMDL. i. The Permittee must sample discharges weekly, unless otherwise specified by the TMDL, to evaluate compliance with the specific waste load allocations or requirements. ii. Analytical methods used to meet the monitoring requirements must conform to the latest revision of the Guidelines Establishing Test Procedures for the Analysis of Pollutants contained in 40 CFR Part 136. iii. Turbidity and pH methods need not be accredited or registered unless conducted at a laboratory which must otherwise be accredited or registered. b. Where an applicable TMDL has established a general waste load allocation for construction stormwater discharges, but has not identified specific requirements, compliance with Special Conditions S4 (Monitoring) and S9 (SWPPPs) will constitute compliance with the approved TMDL. c. Where an applicable TMDL has not specified a waste load allocation for construction stormwater discharges, but has not excluded these discharges, compliance with Special Conditions S4 (Monitoring) and S9 (SWPPPs) will constitute compliance with the approved TMDL. d. Where an applicable TMDL specifically precludes or prohibits discharges from construction activity, the operator is not eligible for coverage under this permit. S9. STORMWATER POLLUTION PREVENTION PLAN The Permittee must prepare and properly implement an adequate Stormwater Pollution Prevention Plan (SWPPP) for construction activity in accordance with the requirements of this permit beginning with initial soil disturbance and until final stabilization. A. The Permittee’s SWPPP must meet the following objectives: 1. To identify best management practices (BMPs) which prevent erosion and sedimentation, and to reduce, eliminate or prevent stormwater contamination and water pollution from construction activity. 2. To prevent violations of surface water quality, groundwater quality, or sediment management standards. 3. To control peak volumetric flow rates and velocities of stormwater discharges. 159 of 347 B. General Requirements 1. The SWPPP must include a narrative and drawings. All BMPs must be clearly referenced in the narrative and marked on the drawings. The SWPPP narrative must include documentation to explain and justify the pollution prevention decisions made for the project. Documentation must include: a. Information about existing site conditions (topography, drainage, soils, vegetation, etc.). b. Potential erosion problem areas. c. The 13 elements of a SWPPP in Special Condition S9.D.1-13, including BMPs used to address each element. d. Construction phasing/sequence and general BMP implementation schedule. e. The actions to be taken if BMP performance goals are not achieved—for example, a contingency plan for additional treatment and/or storage of stormwater that would violate the water quality standards if discharged. f. Engineering calculations for ponds, treatment systems, and any other designed structures. When a treatment system requires engineering calculations, these calculations must be included in the SWPPP. Engineering calculations do not need to be included in the SWPPP for treatment systems that do not require such calculations. 2. The Permittee must modify the SWPPP if, during inspections or investigations conducted by the owner/operator, or the applicable local or state regulatory authority, it is determined that the SWPPP is, or would be, ineffective in eliminating or significantly minimizing pollutants in stormwater discharges from the site. The Permittee must then: a. Review the SWPPP for compliance with Special Condition S9 and make appropriate revisions within 7 days of the inspection or investigation. b. Immediately begin the process to fully implement and maintain appropriate source control and/or treatment BMPs as soon as possible, addressing the problems no later than 10 days from the inspection or investigation. If installation of necessary treatment BMPs is not feasible within 10 days, Ecology may approve additional time when an extension is requested by a Permittee within the initial 10-day response period. c. Document BMP implementation and maintenance in the site log book. The Permittee must modify the SWPPP whenever there is a change in design, construction, operation, or maintenance at the construction site that has, or could have, a significant effect on the discharge of pollutants to waters of the State. C. Stormwater Best Management Practices (BMPs) BMPs must be consistent with: 1. Stormwater Management Manual for Western Washington (most current approved edition at the time this permit was issued), for sites west of the crest of the Cascade Mountains; or 160 of 347 2. Stormwater Management Manual for Eastern Washington (most current approved edition at the time this permit was issued), for sites east of the crest of the Cascade Mountains; or 3. Revisions to the manuals listed in Special Condition S9.C.1 & 2, or other stormwater management guidance documents or manuals which provide an equivalent level of pollution prevention, that are approved by Ecology and incorporated into this permit in accordance with the permit modification requirements of WAC 173-226-230; or 4. Documentation in the SWPPP that the BMPs selected provide an equivalent level of pollution prevention, compared to the applicable stormwater management manuals, including: a. The technical basis for the selection of all stormwater BMPs (scientific, technical studies, and/or modeling) that support the performance claims for the BMPs being selected. b. An assessment of how the selected BMP will satisfy AKART requirements and the applicable federal technology-based treatment requirements under 40 CFR part 125.3. D. SWPPP – Narrative Contents and Requirements The Permittee must include each of the 13 elements below in Special Condition S9.D.1-13 in the narrative of the SWPPP and implement them unless site conditions render the element unnecessary and the exemption from that element is clearly justified in the SWPPP. 1. Preserve Vegetation/Mark Clearing Limits a. Before beginning land-disturbing activities, including clearing and grading, clearly mark all clearing limits, sensitive areas and their buffers, and trees that are to be preserved within the construction area. b. Retain the duff layer, native topsoil, and natural vegetation in an undisturbed state to the maximum degree practicable. 2. Establish Construction Access a. Limit construction vehicle access and exit to one route, if possible. b. Stabilize access points with a pad of quarry spalls, crushed rock, or other equivalent BMPs, to minimize tracking sediment onto roads. c. Locate wheel wash or tire baths on site, if the stabilized construction entrance is not effective in preventing tracking sediment onto roads. d. If sediment is tracked off site, clean the affected roadway thoroughly at the end of each day, or more frequently as necessary (for example, during wet weather). Remove sediment from roads by shoveling, sweeping, or pickup and transport of the sediment to a controlled sediment disposal area. e. Conduct street washing only after sediment removal in accordance with Special Condition S9.D.2.d. f. Control street wash wastewater by pumping back on site or otherwise preventing it from discharging into systems tributary to waters of the State. 161 of 347 3. Control Flow Rates a. Protect properties and waterways downstream of construction sites from erosion and the associated discharge of turbid waters due to increases in the velocity and peak volumetric flow rate of stormwater runoff from the project site, as required by local plan approval authority. b. Where necessary to comply with Special Condition S9.D.3.a, construct stormwater infiltration or detention BMPs as one of the first steps in grading. Assure that detention BMPs function properly before constructing site improvements (for example, impervious surfaces). c. If permanent infiltration ponds are used for flow control during construction, protect these facilities from sedimentation during the construction phase. 4. Install Sediment Controls The Permittee must design, install and maintain effective erosion controls and sediment controls to minimize the discharge of pollutants. At a minimum, the Permittee must: a. Construct sediment control BMPs (sediment ponds, traps, filters, infiltration facilities, etc.) as one of the first steps in grading. These BMPs must be functional before other land disturbing activities take place. b. Minimize sediment discharges from the site. The design, installation and maintenance of erosion and sediment controls must address factors such as the amount, frequency, intensity and duration of precipitation, the nature of resulting stormwater runoff, and soil characteristics, including the range of soil particle sizes expected to be present on the site. c. Direct stormwater runoff from disturbed areas through a sediment pond or other appropriate sediment removal BMP, before the runoff leaves a construction site or before discharge to an infiltration facility. Runoff from fully stabilized areas may be discharged without a sediment removal BMP, but must meet the flow control performance standard of Special Condition S9.D.3.a. d. Locate BMPs intended to trap sediment on site in a manner to avoid interference with the movement of juvenile salmonids attempting to enter off-channel areas or drainages. e. Provide and maintain natural buffers around surface waters, direct stormwater to vegetated areas to increase sediment removal and maximize stormwater infiltration, unless infeasible. f. Where feasible, design outlet structures that withdraw impounded stormwater from the surface to avoid discharging sediment that is still suspended lower in the water column. 5. Stabilize Soils a. The Permittee must stabilize exposed and unworked soils by application of effective BMPs that prevent erosion. Applicable BMPs include, but are not limited to: temporary and permanent seeding, sodding, mulching, plastic covering, erosion 162 of 347 control fabrics and matting, soil application of polyacrylamide (PAM), the early application of gravel base on areas to be paved, and dust control. b. The Permittee must control stormwater volume and velocity within the site to minimize soil erosion. c. The Permittee must control stormwater discharges, including both peak flow rates and total stormwater volume, to minimize erosion at outlets and to minimize downstream channel and stream bank erosion. d. Depending on the geographic location of the project, the Permittee must not allow soils to remain exposed and unworked for more than the time periods set forth below to prevent erosion. West of the Cascade Mountains Crest During the dry season (May 1 - September 30): 7 days During the wet season (October 1 - April 30): 2 days East of the Cascade Mountains Crest, except for Central Basin* During the dry season (July 1 - September 30): 10 days During the wet season (October 1 - June 30): 5 days The Central Basin*, East of the Cascade Mountains Crest During the dry Season (July 1 - September 30): 30 days During the wet season (October 1 - June 30): 15 days *Note: The Central Basin is defined as the portions of Eastern Washington with mean annual precipitation of less than 12 inches. e. The Permittee must stabilize soils at the end of the shift before a holiday or weekend if needed based on the weather forecast. f. The Permittee must stabilize soil stockpiles from erosion, protected with sediment trapping measures, and where possible, be located away from storm drain inlets, waterways, and drainage channels. g. The Permittee must minimize the amount of soil exposed during construction activity. h. The Permittee must minimize the disturbance of steep slopes. i. The Permittee must minimize soil compaction and, unless infeasible, preserve topsoil. 6. Protect Slopes a. The Permittee must design and construct cut-and-fill slopes in a manner to minimize erosion. Applicable practices include, but are not limited to, reducing continuous length of slope with terracing and diversions, reducing slope steepness, and roughening slope surfaces (for example, track walking). b. The Permittee must divert off-site stormwater (run-on) or groundwater away from slopes and disturbed areas with interceptor dikes, pipes, and/or swales. Off-site stormwater should be managed separately from stormwater generated on the site. c. At the top of slopes, collect drainage in pipe slope drains or protected channels to prevent erosion. 163 of 347 i. West of the Cascade Mountains Crest: Temporary pipe slope drains must handle the peak 10-minute flow rate from a Type 1A, 10-year, 24-hour frequency storm for the developed condition. Alternatively, the 10-year, 1-hour flow rate predicted by an approved continuous runoff model, increased by a factor of 1.6, may be used. The hydrologic analysis must use the existing land cover condition for predicting flow rates from tributary areas outside the project limits. For tributary areas on the project site, the analysis must use the temporary or permanent project land cover condition, whichever will produce the highest flow rates. If using the Western Washington Hydrology Model (WWHM) to predict flows, bare soil areas should be modeled as "landscaped area.” ii. East of the Cascade Mountains Crest: Temporary pipe slope drains must handle the expected peak flow rate from a 6-month, 3-hour storm for the developed condition, referred to as the short duration storm. d. Place excavated material on the uphill side of trenches, consistent with safety and space considerations. e. Place check dams at regular intervals within constructed channels that are cut down a slope. 7. Protect Drain Inlets a. Protect all storm drain inlets made operable during construction so that stormwater runoff does not enter the conveyance system without first being filtered or treated to remove sediment. b. Clean or remove and replace inlet protection devices when sediment has filled one- third of the available storage (unless a different standard is specified by the product manufacturer). 8. Stabilize Channels and Outlets a. Design, construct and stabilize all on-site conveyance channels to prevent erosion from the following expected peak flows: i. West of the Cascade Mountains Crest: Channels must handle the peak 10- minute flow rate from a Type 1A, 10-year, 24-hour frequency storm for the developed condition. Alternatively, the 10-year, 1-hour flow rate indicated by an approved continuous runoff model, increased by a factor of 1.6, may be used. The hydrologic analysis must use the existing land cover condition for predicting flow rates from tributary areas outside the project limits. For tributary areas on the project site, the analysis must use the temporary or permanent project land cover condition, whichever will produce the highest flow rates. If using the WWHM to predict flows, bare soil areas should be modeled as "landscaped area.” ii. East of the Cascade Mountains Crest: Channels must handle the expected peak flow rate from a 6-month, 3-hour storm for the developed condition, referred to as the short duration storm. b. Provide stabilization, including armoring material, adequate to prevent erosion of outlets, adjacent stream banks, slopes, and downstream reaches at the outlets of all conveyance systems. 164 of 347 9. Control Pollutants Design, install, implement and maintain effective pollution prevention measures to minimize the discharge of pollutants. The Permittee must: a. Handle and dispose of all pollutants, including waste materials and demolition debris that occur on site in a manner that does not cause contamination of stormwater. b. Provide cover, containment, and protection from vandalism for all chemicals, liquid products, petroleum products, and other materials that have the potential to pose a threat to human health or the environment. Minimize storage of hazardous materials on-site. Safety Data Sheets (SDS) should be supplied for all materials stored. Chemicals should be kept in their original labeled containers. On-site fueling tanks must include secondary containment. Secondary containment means placing tanks or containers within an impervious structure capable of containing 110% of the volume of the largest tank within the containment structure. Double-walled tanks do not require additional secondary containment. c. Conduct maintenance, fueling, and repair of heavy equipment and vehicles using spill prevention and control measures. Clean contaminated surfaces immediately following any spill incident. d. Discharge wheel wash or tire bath wastewater to a separate on-site treatment system that prevents discharge to surface water, such as closed-loop recirculation or upland land application, or to the sanitary sewer with local sewer district approval. e. Apply fertilizers and pesticides in a manner and at application rates that will not result in loss of chemical to stormwater runoff. Follow manufacturers’ label requirements for application rates and procedures. f. Use BMPs to prevent contamination of stormwater runoff by pH-modifying sources. The sources for this contamination include, but are not limited to: bulk cement, cement kiln dust, fly ash, new concrete washing and curing waters, recycled concrete stockpiles, waste streams generated from concrete grinding and sawing, exposed aggregate processes, dewatering concrete vaults, concrete pumping and mixer washout waters. (Also refer to the definition for "concrete wastewater" in Appendix A – Definitions.) g. Adjust the pH of stormwater or authorized non-stormwater if necessary to prevent an exceedance of groundwater and/or surface water quality standards. h. Assure that washout of concrete trucks is performed off-site or in designated concrete washout areas only. Do not wash out concrete truck drums onto the ground, or into storm drains, open ditches, streets, or streams. Washout of small concrete handling equipment may be disposed of in a formed area awaiting concrete where it will not contaminate surface or groundwater. Do not dump excess concrete on site, except in designated concrete washout areas. Concrete spillage or concrete discharge directly to groundwater or surface waters of the State is 165 of 347 prohibited. At no time shall concrete be washed off into the footprint of an area where an infiltration BMP will be installed. i. Obtain written approval from Ecology before using any chemical treatment, with the exception of CO2, dry ice or food grade vinegar, to adjust pH. j. Uncontaminated water from water-only based shaft drilling for construction of building, road, and bridge foundations may be infiltrated provided the wastewater is managed in a way that prohibits discharge to surface waters. Prior to infiltration, water from water-only based shaft drilling that comes into contact with curing concrete must be neutralized until pH is in the range of 6.5 to 8.5 (su). 10. Control Dewatering a. Permittees must discharge foundation, vault, and trench dewatering water, which have characteristics similar to stormwater runoff at the site, in conjunction with BMPs to reduce sedimentation before discharge to a sediment trap or sediment pond. b. Permittees may discharge clean, non-turbid dewatering water, such as well-point groundwater, to systems tributary to, or directly into surface waters of the State, as specified in Special Condition S9.D.8, provided the dewatering flow does not cause erosion or flooding of receiving waters. Do not route clean dewatering water through stormwater sediment ponds. Note that “surface waters of the State” may exist on a construction site as well as off site; for example, a creek running through a site. c. Other dewatering treatment or disposal options may include: i. Infiltration ii. Transport off site in a vehicle, such as a vacuum flush truck, for legal disposal in a manner that does not pollute state waters. iii. Ecology-approved on-site chemical treatment or other suitable treatment technologies (See S9.D.9.i, regarding chemical treatment written approval). iv. Sanitary or combined sewer discharge with local sewer district approval, if there is no other option. v. Use of a sedimentation bag with discharge to a ditch or swale for small volumes of localized dewatering. d. Permittees must handle highly turbid or contaminated dewatering water separately from stormwater. 11. Maintain BMPs a. Permittees must maintain and repair all temporary and permanent erosion and sediment control BMPs as needed to assure continued performance of their intended function in accordance with BMP specifications. b. Permittees must remove all temporary erosion and sediment control BMPs within 30 days after achieving final site stabilization or after the temporary BMPs are no longer needed. 166 of 347 12. Manage the Project a. Phase development projects to the maximum degree practicable and take into account seasonal work limitations. b. Inspect, maintain and repair all BMPs as needed to assure continued performance of their intended function. Conduct site inspections and monitoring in accordance with Special Condition S4. c. Maintain, update, and implement the SWPPP in accordance with Special Conditions S3, S4, and S9. 13. Protect Low Impact Development (LID) BMPs The primary purpose of on-site LID Stormwater Management is to reduce the disruption of the natural site hydrology through infiltration. LID BMPs are permanent facilities. a. Permittees must protect all LID BMPs (including, but not limited to, Bioretention and Rain Garden facilities) from sedimentation through installation and maintenance of erosion and sediment control BMPs on portions of the site that drain into the Bioretention and/or Rain Garden facilities. Restore the BMPs to their fully functioning condition if they accumulate sediment during construction. Restoring the facility must include removal of sediment and any sediment-laden bioretention/ rain garden soils, and replacing the removed soils with soils meeting the design specification. b. Permittees must maintain the infiltration capabilities of LID BMPs by protecting against compaction by construction equipment and foot traffic. Protect completed lawn and landscaped areas from compaction due to construction equipment. c. Permittees must control erosion and avoid introducing sediment from surrounding land uses onto permeable pavements. Do not allow muddy construction equipment on the base material or pavement. Do not allow sediment-laden runoff onto permeable pavements or base materials. d. Permittees must clean permeable pavements fouled with sediments or no longer passing an initial infiltration test using local stormwater manual methodology or the manufacturer’s procedures. e. Permittees must keep all heavy equipment off existing soils under LID BMPs that have been excavated to final grade to retain the infiltration rate of the soils. E. SWPPP – Map Contents and Requirements The Permittee’s SWPPP must also include a vicinity map or general location map (for example, a USGS quadrangle map, a portion of a county or city map, or other appropriate map) with enough detail to identify the location of the construction site and receiving waters within one mile of the site. The SWPPP must also include a legible site map (or maps) showing the entire construction site. The following features must be identified, unless not applicable due to site conditions. 1. The direction of north, property lines, and existing structures and roads. 2. Cut and fill slopes indicating the top and bottom of slope catch lines. 167 of 347 3. Approximate slopes, contours, and direction of stormwater flow before and after major grading activities. 4. Areas of soil disturbance and areas that will not be disturbed. 5. Locations of structural and nonstructural controls (BMPs) identified in the SWPPP. 6. Locations of off-site material, stockpiles, waste storage, borrow areas, and vehicle/equipment storage areas. 7. Locations of all surface water bodies, including wetlands. 8. Locations where stormwater or non-stormwater discharges off-site and/or to a surface waterbody, including wetlands. 9. Location of water quality sampling station(s), if sampling is required by state or local permitting authority. 10. Areas where final stabilization has been accomplished and no further construction-phase permit requirements apply. 11. Location or proposed location of LID facilities. S10. NOTICE OF TERMINATION Partial terminations of permit coverage are not authorized. A. The site is eligible for termination of coverage when it has met any of the following conditions: 1. The site has undergone final stabilization, the Permittee has removed all temporary BMPs (except biodegradable BMPs clearly manufactured with the intention for the material to be left in place and not interfere with maintenance or land use), and all stormwater discharges associated with construction activity have been eliminated; or 2. All portions of the site that have not undergone final stabilization per Special Condition S10.A.1 have been sold and/or transferred (per Special Condition S2.A), and the Permittee no longer has operational control of the construction activity; or 3. For residential construction only, the Permittee has completed temporary stabilization and the homeowners have taken possession of the residences. B. When the site is eligible for termination, the Permittee must submit a complete and accurate Notice of Termination (NOT) form, signed in accordance with General Condition G2, to: Department of Ecology Water Quality Program - Construction Stormwater PO Box 47696 Olympia, WA 98504-7696 168 of 347 When an electronic termination form is available, the Permittee may choose to submit a complete and accurate Notice of Termination (NOT) form through the Water Quality Permitting Portal rather than mailing a hardcopy as noted above. The termination is effective on the 31st calendar day following the date Ecology receives a complete NOT form, unless Ecology notifies the Permittee that termination request is denied because the Permittee has not met the eligibility requirements in Special Condition S10.A. Permittees are required to comply with all conditions and effluent limitations in the permit until the permit has been terminated. Permittees transferring the property to a new property owner or operator/Permittee are required to complete and submit the Notice of Transfer form to Ecology, but are not required to submit a Notice of Termination form for this type of transaction. 169 of 347 GENERAL CONDITIONS G1. DISCHARGE VIOLATIONS All discharges and activities authorized by this general permit must be consistent with the terms and conditions of this general permit. Any discharge of any pollutant more frequent than or at a level in excess of that identified and authorized by the general permit must constitute a violation of the terms and conditions of this permit. G2. SIGNATORY REQUIREMENTS A. All permit applications must bear a certification of correctness to be signed: 1. In the case of corporations, by a responsible corporate officer. 2. In the case of a partnership, by a general partner of a partnership. 3. In the case of sole proprietorship, by the proprietor. 4. In the case of a municipal, state, or other public facility, by either a principal executive officer or ranking elected official. B. All reports required by this permit and other information requested by Ecology (including NOIs, NOTs, and Transfer of Coverage forms) must be signed by a person described above or by a duly authorized representative of that person. A person is a duly authorized representative only if: 1. The authorization is made in writing by a person described above and submitted to Ecology. 2. The authorization specifies either an individual or a position having responsibility for the overall operation of the regulated facility, such as the position of plant manager, superintendent, position of equivalent responsibility, or an individual or position having overall responsibility for environmental matters. C. Changes to authorization. If an authorization under paragraph G2.B.2 above is no longer accurate because a different individual or position has responsibility for the overall operation of the facility, a new authorization satisfying the requirements of paragraph G2.B.2 above must be submitted to Ecology prior to or together with any reports, information, or applications to be signed by an authorized representative. D. Certification. Any person signing a document under this section must make the following certification: I certify under penalty of law, that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. 170 of 347 G3. RIGHT OF INSPECTION AND ENTRY The Permittee must allow an authorized representative of Ecology, upon the presentation of credentials and such other documents as may be required by law: A. To enter upon the premises where a discharge is located or where any records are kept under the terms and conditions of this permit. B. To have access to and copy, at reasonable times and at reasonable cost, any records required to be kept under the terms and conditions of this permit. C. To inspect, at reasonable times, any facilities, equipment (including monitoring and control equipment), practices, methods, or operations regulated or required under this permit. D. To sample or monitor, at reasonable times, any substances or parameters at any location for purposes of assuring permit compliance or as otherwise authorized by the Clean Water Act. G4. GENERAL PERMIT MODIFICATION AND REVOCATION This permit may be modified, revoked and reissued, or terminated in accordance with the provisions of Chapter 173-226 WAC. Grounds for modification, revocation and reissuance, or termination include, but are not limited to, the following: A. When a change occurs in the technology or practices for control or abatement of pollutants applicable to the category of dischargers covered under this permit. B. When effluent limitation guidelines or standards are promulgated pursuant to the CWA or Chapter 90.48 RCW, for the category of dischargers covered under this permit. C. When a water quality management plan containing requirements applicable to the category of dischargers covered under this permit is approved, or D. When information is obtained that indicates cumulative effects on the environment from dischargers covered under this permit are unacceptable. G5. REVOCATION OF COVERAGE UNDER THE PERMIT Pursuant to Chapter 43.21B RCW and Chapter 173-226 WAC, the Director may terminate coverage for any discharger under this permit for cause. Cases where coverage may be terminated include, but are not limited to, the following: A. Violation of any term or condition of this permit. B. Obtaining coverage under this permit by misrepresentation or failure to disclose fully all relevant facts. C. A change in any condition that requires either a temporary or permanent reduction or elimination of the permitted discharge. D. Failure or refusal of the Permittee to allow entry as required in RCW 90.48.090. E. A determination that the permitted activity endangers human health or the environment, or contributes to water quality standards violations. F. Nonpayment of permit fees or penalties assessed pursuant to RCW 90.48.465 and Chapter 173-224 WAC. 171 of 347 G. Failure of the Permittee to satisfy the public notice requirements of WAC 173-226-130(5), when applicable. The Director may require any discharger under this permit to apply for and obtain coverage under an individual permit or another more specific general permit. Permittees who have their coverage revoked for cause according to WAC 173-226-240 may request temporary coverage under this permit during the time an individual permit is being developed, provided the request is made within ninety (90) days from the time of revocation and is submitted along with a complete individual permit application form. G6. REPORTING A CAUSE FOR MODIFICATION The Permittee must submit a new application, or a supplement to the previous application, whenever a material change to the construction activity or in the quantity or type of discharge is anticipated which is not specifically authorized by this permit. This application must be submitted at least sixty (60) days prior to any proposed changes. Filing a request for a permit modification, revocation and reissuance, or termination, or a notification of planned changes or anticipated noncompliance does not relieve the Permittee of the duty to comply with the existing permit until it is modified or reissued. G7. COMPLIANCE WITH OTHER LAWS AND STATUTES Nothing in this permit will be construed as excusing the Permittee from compliance with any applicable federal, state, or local statutes, ordinances, or regulations. G8. DUTY TO REAPPLY The Permittee must apply for permit renewal at least 180 days prior to the specified expiration date of this permit. The Permittee must reapply using the electronic application form (NOI) available on Ecology’s website. Permittees unable to submit electronically (for example, those who do not have an internet connection) must contact Ecology to request a waiver and obtain instructions on how to obtain a paper NOI. Department of Ecology Water Quality Program - Construction Stormwater PO Box 47696 Olympia, WA 98504-7696 G9. REMOVED SUBSTANCE The Permittee must not re-suspend or reintroduce collected screenings, grit, solids, sludges, filter backwash, or other pollutants removed in the course of treatment or control of stormwater to the final effluent stream for discharge to state waters. G10. DUTY TO PROVIDE INFORMATION The Permittee must submit to Ecology, within a reasonable time, all information that Ecology may request to determine whether cause exists for modifying, revoking and reissuing, or terminating this permit or to determine compliance with this permit. The Permittee must also submit to Ecology, upon request, copies of records required to be kept by this permit [40 CFR 122.41(h)]. 172 of 347 G11. OTHER REQUIREMENTS OF 40 CFR All other requirements of 40 CFR 122.41 and 122.42 are incorporated in this permit by reference. G12. ADDITIONAL MONITORING Ecology may establish specific monitoring requirements in addition to those contained in this permit by administrative order or permit modification. G13. PENALTIES FOR VIOLATING PERMIT CONDITIONS Any person who is found guilty of willfully violating the terms and conditions of this permit shall be deemed guilty of a crime, and upon conviction thereof shall be punished by a fine of up to ten thousand dollars ($10,000) and costs of prosecution, or by imprisonment at the discretion of the court. Each day upon which a willful violation occurs may be deemed a separate and additional violation. Any person who violates the terms and conditions of a waste discharge permit shall incur, in addition to any other penalty as provided by law, a civil penalty in the amount of up to ten thousand dollars ($10,000) for every such violation. Each and every such violation shall be a separate and distinct offense, and in case of a continuing violation, every day’s continuance shall be deemed to be a separate and distinct violation. G14. UPSET Definition – “Upset” means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the Permittee. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. An upset constitutes an affirmative defense to an action brought for noncompliance with such technology-based permit effluent limitations if the requirements of the following paragraph are met. A Permittee who wishes to establish the affirmative defense of upset must demonstrate, through properly signed, contemporaneous operating logs or other relevant evidence that: 1) an upset occurred and that the Permittee can identify the cause(s) of the upset; 2) the permitted facility was being properly operated at the time of the upset; 3) the Permittee submitted notice of the upset as required in Special Condition S5.F, and; 4) the Permittee complied with any remedial measures required under this permit. In any enforcement proceeding, the Permittee seeking to establish the occurrence of an upset has the burden of proof. G15. PROPERTY RIGHTS This permit does not convey any property rights of any sort, or any exclusive privilege. G16. DUTY TO COMPLY The Permittee must comply with all conditions of this permit. Any permit noncompliance constitutes a violation of the Clean Water Act and is grounds for enforcement action; for permit termination, revocation and reissuance, or modification; or denial of a permit renewal application. 173 of 347 G17. TOXIC POLLUTANTS The Permittee must comply with effluent standards or prohibitions established under Section 307(a) of the Clean Water Act for toxic pollutants within the time provided in the regulations that establish those standards or prohibitions, even if this permit has not yet been modified to incorporate the requirement. G18. PENALTIES FOR TAMPERING The Clean Water Act provides that any person who falsifies, tampers with, or knowingly renders inaccurate any monitoring device or method required to be maintained under this permit shall, upon conviction, be punished by a fine of not more than $10,000 per violation, or by imprisonment for not more than two years per violation, or by both. If a conviction of a person is for a violation committed after a first conviction of such person under this condition, punishment shall be a fine of not more than $20,000 per day of violation, or imprisonment of not more than four (4) years, or both. G19. REPORTING PLANNED CHANGES The Permittee must, as soon as possible, give notice to Ecology of planned physical alterations, modifications or additions to the permitted construction activity. The Permittee should be aware that, depending on the nature and size of the changes to the original permit, a new public notice and other permit process requirements may be required. Changes in activities that require reporting to Ecology include those that will result in: A. The permitted facility being determined to be a new source pursuant to 40 CFR 122.29(b). B. A significant change in the nature or an increase in quantity of pollutants discharged, including but not limited to: a 20% or greater increase in acreage disturbed by construction activity. C. A change in or addition of surface water(s) receiving stormwater or non-stormwater from the construction activity. D. A change in the construction plans and/or activity that affects the Permittee’s monitoring requirements in Special Condition S4. Following such notice, permit coverage may be modified, or revoked and reissued pursuant to 40 CFR 122.62(a) to specify and limit any pollutants not previously limited. Until such modification is effective, any new or increased discharge in excess of permit limits or not specifically authorized by this permit constitutes a violation. G20. REPORTING OTHER INFORMATION Where the Permittee becomes aware that it failed to submit any relevant facts in a permit application, or submitted incorrect information in a permit application or in any report to Ecology, it must promptly submit such facts or information. G21. REPORTING ANTICIPATED NON-COMPLIANCE The Permittee must give advance notice to Ecology by submission of a new application or supplement thereto at least forty-five (45) days prior to commencement of such discharges, of any facility expansions, production increases, or other planned changes, such as process modifications, in the permitted facility or activity which may result in noncompliance with permit limits or conditions. Any maintenance of facilities, which might necessitate unavoidable interruption of 174 of 347 operation and degradation of effluent quality, must be scheduled during non-critical water quality periods and carried out in a manner approved by Ecology. G22. REQUESTS TO BE EXCLUDED FROM COVERAGE UNDER THE PERMIT Any discharger authorized by this permit may request to be excluded from coverage under the general permit by applying for an individual permit. The discharger must submit to the Director an application as described in WAC 173-220-040 or WAC 173-216-070, whichever is applicable, with reasons supporting the request. These reasons will fully document how an individual permit will apply to the applicant in a way that the general permit cannot. Ecology may make specific requests for information to support the request. The Director will either issue an individual permit or deny the request with a statement explaining the reason for the denial. When an individual permit is issued to a discharger otherwise subject to the construction stormwater general permit, the applicability of the construction stormwater general permit to that Permittee is automatically terminated on the effective date of the individual permit. G23. APPEALS A. The terms and conditions of this general permit, as they apply to the appropriate class of dischargers, are subject to appeal by any person within 30 days of issuance of this general permit, in accordance with Chapter 43.21B RCW, and Chapter 173-226 WAC. B. The terms and conditions of this general permit, as they apply to an individual discharger, are appealable in accordance with Chapter 43.21B RCW within 30 days of the effective date of coverage of that discharger. Consideration of an appeal of general permit coverage of an individual discharger is limited to the general permit’s applicability or nonapplicability to that individual discharger. C. The appeal of general permit coverage of an individual discharger does not affect any other dischargers covered under this general permit. If the terms and conditions of this general permit are found to be inapplicable to any individual discharger(s), the matter shall be remanded to Ecology for consideration of issuance of an individual permit or permits. G24. SEVERABILITY The provisions of this permit are severable, and if any provision of this permit, or application of any provision of this permit to any circumstance, is held invalid, the application of such provision to other circumstances, and the remainder of this permit shall not be affected thereby. G25. BYPASS PROHIBITED A. Bypass Procedures Bypass, which is the intentional diversion of waste streams from any portion of a treatment facility, is prohibited for stormwater events below the design criteria for stormwater management. Ecology may take enforcement action against a Permittee for bypass unless one of the following circumstances (1, 2, 3 or 4) is applicable. 1. Bypass of stormwater is consistent with the design criteria and part of an approved management practice in the applicable stormwater management manual. 2. Bypass for essential maintenance without the potential to cause violation of permit limits or conditions. 175 of 347 Bypass is authorized if it is for essential maintenance and does not have the potential to cause violations of limitations or other conditions of this permit, or adversely impact public health. 3. Bypass of stormwater is unavoidable, unanticipated, and results in noncompliance of this permit. This bypass is permitted only if: a. Bypass is unavoidable to prevent loss of life, personal injury, or severe property damage. “Severe property damage” means substantial physical damage to property, damage to the treatment facilities which would cause them to become inoperable, or substantial and permanent loss of natural resources which can reasonably be expected to occur in the absence of a bypass. b. There are no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, maintenance during normal periods of equipment downtime (but not if adequate backup equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass which occurred during normal periods of equipment downtime or preventative maintenance), or transport of untreated wastes to another treatment facility. c. Ecology is properly notified of the bypass as required in Special Condition S5.F of this permit. 4. A planned action that would cause bypass of stormwater and has the potential to result in noncompliance of this permit during a storm event. The Permittee must notify Ecology at least thirty (30) days before the planned date of bypass. The notice must contain: a. A description of the bypass and its cause b. An analysis of all known alternatives which would eliminate, reduce, or mitigate the need for bypassing. c. A cost-effectiveness analysis of alternatives including comparative resource damage assessment. d. The minimum and maximum duration of bypass under each alternative. e. A recommendation as to the preferred alternative for conducting the bypass. f. The projected date of bypass initiation. g. A statement of compliance with SEPA. h. A request for modification of water quality standards as provided for in WAC 173- 201A-110, if an exceedance of any water quality standard is anticipated. i. Steps taken or planned to reduce, eliminate, and prevent reoccurrence of the bypass. 5. For probable construction bypasses, the need to bypass is to be identified as early in the planning process as possible. The analysis required above must be considered during 176 of 347 preparation of the Stormwater Pollution Prevention Plan (SWPPP) and must be included to the extent practical. In cases where the probable need to bypass is determined early, continued analysis is necessary up to and including the construction period in an effort to minimize or eliminate the bypass. Ecology will consider the following before issuing an administrative order for this type bypass: a. If the bypass is necessary to perform construction or maintenance-related activities essential to meet the requirements of this permit. b. If there are feasible alternatives to bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes, stopping production, maintenance during normal periods of equipment down time, or transport of untreated wastes to another treatment facility. c. If the bypass is planned and scheduled to minimize adverse effects on the public and the environment. After consideration of the above and the adverse effects of the proposed bypass and any other relevant factors, Ecology will approve, conditionally approve, or deny the request. The public must be notified and given an opportunity to comment on bypass incidents of significant duration, to the extent feasible. Approval of a request to bypass will be by administrative order issued by Ecology under RCW 90.48.120. B. Duty to Mitigate The Permittee is required to take all reasonable steps to minimize or prevent any discharge or sludge use or disposal in violation of this permit that has a reasonable likelihood of adversely affecting human health or the environment. 177 of 347 APPENDIX A – DEFINITIONS AKART is an acronym for “All Known, Available, and Reasonable methods of prevention, control, and Treatment.” AKART represents the most current methodology that can be reasonably required for preventing, controlling, or abating the pollutants and controlling pollution associated with a discharge. Applicable TMDL means a TMDL for turbidity, fine sediment, high pH, or phosphorus, which was completed and approved by EPA before January 1, 2021, or before the date the operator’s complete permit application is received by Ecology, whichever is later. TMDLs completed after a complete permit application is received by Ecology become applicable to the Permittee only if they are imposed through an administrative order by Ecology, or through a modification of permit coverage. Applicant means an operator seeking coverage under this permit. Benchmark means a pollutant concentration used as a permit threshold, below which a pollutant is considered unlikely to cause a water quality violation, and above which it may. When pollutant concentrations exceed benchmarks, corrective action requirements take effect. Benchmark values are not water quality standards and are not numeric effluent limitations; they are indicator values. Best Management Practices (BMPs) means schedules of activities, prohibitions of practices, maintenance procedures, and other physical, structural and/or managerial practices to prevent or reduce the pollution of waters of the State. BMPs include treatment systems, operating procedures, and practices to control stormwater associated with construction activity, spillage or leaks, sludge or waste disposal, or drainage from raw material storage. Buffer means an area designated by a local jurisdiction that is contiguous to and intended to protect a sensitive area. Bypass means the intentional diversion of waste streams from any portion of a treatment facility. Calendar Day A period of 24 consecutive hours starting at 12:00 midnight and ending the following 12:00 midnight. Calendar Week (same as Week) means a period of seven consecutive days starting at 12:01 a.m. (0:01 hours) on Sunday. Certified Erosion and Sediment Control Lead (CESCL) means a person who has current certification through an approved erosion and sediment control training program that meets the minimum training standards established by Ecology (See BMP C160 in the SWMM). Chemical Treatment means the addition of chemicals to stormwater and/or authorized non-stormwater prior to filtration and discharge to surface waters. Clean Water Act (CWA) means the Federal Water Pollution Control Act enacted by Public Law 92-500, as amended by Public Laws 95-217, 95-576, 96-483, and 97-117; USC 1251 et seq. Combined Sewer means a sewer which has been designed to serve as a sanitary sewer and a storm sewer, and into which inflow is allowed by local ordinance. 178 of 347 Common Plan of Development or Sale means a site where multiple separate and distinct construction activities may be taking place at different times on different schedules and/or by different contractors, but still under a single plan. Examples include: 1) phased projects and projects with multiple filings or lots, even if the separate phases or filings/lots will be constructed under separate contract or by separate owners (e.g., a development where lots are sold to separate builders); 2) a development plan that may be phased over multiple years, but is still under a consistent plan for long-term development; 3) projects in a contiguous area that may be unrelated but still under the same contract, such as construction of a building extension and a new parking lot at the same facility; and 4) linear projects such as roads, pipelines, or utilities. If the project is part of a common plan of development or sale, the disturbed area of the entire plan must be used in determining permit requirements. Composite Sample means a mixture of grab samples collected at the same sampling point at different times, formed either by continuous sampling or by mixing discrete samples. May be "time-composite" (collected at constant time intervals) or "flow-proportional" (collected either as a constant sample volume at time intervals proportional to stream flow, or collected by increasing the volume of each aliquot as the flow increases while maintaining a constant time interval between the aliquots. Concrete Wastewater means any water used in the production, pouring and/or clean-up of concrete or concrete products, and any water used to cut, grind, wash, or otherwise modify concrete or concrete products. Examples include water used for or resulting from concrete truck/mixer/pumper/tool/chute rinsing or washing, concrete saw cutting and surfacing (sawing, coring, grinding, roughening, hydro- demolition, bridge and road surfacing). When stormwater comingles with concrete wastewater, the resulting water is considered concrete wastewater and must be managed to prevent discharge to waters of the State, including groundwater. Construction Activity means land disturbing operations including clearing, grading or excavation which disturbs the surface of the land (including off-site disturbance acreage related to construction-support activity). Such activities may include road construction, construction of residential houses, office buildings, or industrial buildings, site preparation, soil compaction, movement and stockpiling of topsoils, and demolition activity. Construction Support Activity means off-site acreage that will be disturbed as a direct result of the construction project and will discharge stormwater. For example, off-site equipment staging yards, material storage areas, borrow areas, and parking areas. Contaminant means any hazardous substance that does not occur naturally or occurs at greater than natural background levels. See definition of “hazardous substance” and WAC 173-340-200. Contaminated soil means soil which contains contaminants, pollutants, or hazardous substances that do not occur naturally or occur at levels greater than natural background. Contaminated groundwater means groundwater which contains contaminants, pollutants, or hazardous substances that do not occur naturally or occur at levels greater than natural background. Demonstrably Equivalent means that the technical basis for the selection of all stormwater BMPs is documented within a SWPPP, including: 1. The method and reasons for choosing the stormwater BMPs selected. 2. The pollutant removal performance expected from the BMPs selected. 179 of 347 3. The technical basis supporting the performance claims for the BMPs selected, including any available data concerning field performance of the BMPs selected. 4. An assessment of how the selected BMPs will comply with state water quality standards. 5. An assessment of how the selected BMPs will satisfy both applicable federal technology-based treatment requirements and state requirements to use all known, available, and reasonable methods of prevention, control, and treatment (AKART). Department means the Washington State Department of Ecology. Detention means the temporary storage of stormwater to improve quality and/or to reduce the mass flow rate of discharge. Dewatering means the act of pumping groundwater or stormwater away from an active construction site. Director means the Director of the Washington State Department of Ecology or his/her authorized representative. Discharger means an owner or operator of any facility or activity subject to regulation under Chapter 90.48 RCW or the Federal Clean Water Act. Domestic Wastewater means water carrying human wastes, including kitchen, bath, and laundry wastes from residences, buildings, industrial establishments, or other places, together with such groundwater infiltration or surface waters as may be present. Ecology means the Washington State Department of Ecology. Engineered Soils means the use of soil amendments including, but not limited, to Portland cement treated base (CTB), cement kiln dust (CKD), or fly ash to achieve certain desirable soil characteristics. Equivalent BMPs means operational, source control, treatment, or innovative BMPs which result in equal or better quality of stormwater discharge to surface water or to groundwater than BMPs selected from the SWMM. Erosion means the wearing away of the land surface by running water, wind, ice, or other geological agents, including such processes as gravitational creep. Erosion and Sediment Control BMPs means BMPs intended to prevent erosion and sedimentation, such as preserving natural vegetation, seeding, mulching and matting, plastic covering, filter fences, sediment traps, and ponds. Erosion and sediment control BMPs are synonymous with stabilization and structural BMPs. Federal Operator is an entity that meets the definition of “Operator” in this permit and is either any department, agency or instrumentality of the executive, legislative, and judicial branches of the Federal government of the United States, or another entity, such as a private contractor, performing construction activity for any such department, agency, or instrumentality. Final Stabilization (same as fully stabilized or full stabilization) means the completion of all soil disturbing activities at the site and the establishment of permanent vegetative cover, or equivalent permanent stabilization measures (such as pavement, riprap, gabions, or geotextiles) which will prevent erosion. See the applicable Stormwater Management Manual for more information on vegetative cover expectations and equivalent permanent stabilization measures. 180 of 347 Groundwater means water in a saturated zone or stratum beneath the land surface or a surface waterbody. Hazardous Substance means any dangerous or extremely hazardous waste as defined in RCW 70.105.010 (5) and (6), or any dangerous or extremely dangerous waste as designated by rule under chapter 70.105 RCW; any hazardous sub-stance as defined in RCW 70.105.010(14) or any hazardous substance as defined by rule under chapter 70.105 RCW; any substance that, on the effective date of this section, is a hazardous substance under section 101(14) of the federal cleanup law, 42U.S.C., Sec. 9601(14); petroleum or petroleum products; and any substance or category of substances, including solid waste decomposition products, determined by the director by rule to present a threat to human health or the environment if released into the environment. The term hazardous substance does not include any of the following when contained in an underground storage tank from which there is not a release: crude oil or any fraction thereof or petroleum, if the tank is in compliance with all applicable federal, state, and local law. Injection Well means a well that is used for the subsurface emplacement of fluids. (See Well.) Jurisdiction means a political unit such as a city, town or county; incorporated for local self-government. National Pollutant Discharge Elimination System (NPDES) means the national program for issuing, modifying, revoking and reissuing, terminating, monitoring, and enforcing permits, and imposing and enforcing pretreatment requirements, under sections 307, 402, 318, and 405 of the Federal Clean Water Act, for the discharge of pollutants to surface waters of the State from point sources. These permits are referred to as NPDES permits and, in Washington State, are administered by the Washington State Department of Ecology. Notice of Intent (NOI) means the application for, or a request for coverage under this general permit pursuant to WAC 173-226-200. Notice of Termination (NOT) means a request for termination of coverage under this general permit as specified by Special Condition S10 of this permit. Operator means any party associated with a construction project that meets either of the following two criteria: • The party has operational control over construction plans and specifications, including the ability to make modifications to those plans and specifications; or • The party has day-to-day operational control of those activities at a project that are necessary to ensure compliance with a SWPPP for the site or other permit conditions (e.g., they are authorized to direct workers at a site to carry out activities required by the SWPPP or comply with other permit conditions). Permittee means individual or entity that receives notice of coverage under this general permit. pH means a liquid’s measure of acidity or alkalinity. A pH of 7 is defined as neutral. Large variations above or below this value are considered harmful to most aquatic life. pH Monitoring Period means the time period in which the pH of stormwater runoff from a site must be tested a minimum of once every seven days to determine if stormwater pH is between 6.5 and 8.5. 181 of 347 Point Source means any discernible, confined, and discrete conveyance, including but not limited to, any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, and container from which pollutants are or may be discharged to surface waters of the State. This term does not include return flows from irrigated agriculture. (See the Fact Sheet for further explanation) Pollutant means dredged spoil, solid waste, incinerator residue, filter backwash, sewage, garbage, domestic sewage sludge (biosolids), munitions, chemical wastes, biological materials, radioactive materials, heat, wrecked or discarded equipment, rock, sand, cellar dirt, and industrial, municipal, and agricultural waste. This term does not include sewage from vessels within the meaning of section 312 of the CWA, nor does it include dredged or fill material discharged in accordance with a permit issued under section 404 of the CWA. Pollution means contamination or other alteration of the physical, chemical, or biological properties of waters of the State; including change in temperature, taste, color, turbidity, or odor of the waters; or such discharge of any liquid, gaseous, solid, radioactive or other substance into any waters of the State as will or is likely to create a nuisance or render such waters harmful, detrimental or injurious to the public health, safety or welfare; or to domestic, commercial, industrial, agricultural, recreational, or other legitimate beneficial uses; or to livestock, wild animals, birds, fish or other aquatic life. Process Wastewater means any non-stormwater which, during manufacturing or processing, comes into direct contact with or results from the production or use of any raw material, intermediate product, finished product, byproduct, or waste product. If stormwater commingles with process wastewater, the commingled water is considered process wastewater. Receiving Water means the waterbody at the point of discharge. If the discharge is to a storm sewer system, either surface or subsurface, the receiving water is the waterbody to which the storm system discharges. Systems designed primarily for other purposes such as for groundwater drainage, redirecting stream natural flows, or for conveyance of irrigation water/return flows that coincidentally convey stormwater are considered the receiving water. Representative means a stormwater or wastewater sample which represents the flow and characteristics of the discharge. Representative samples may be a grab sample, a time-proportionate composite sample, or a flow proportionate sample. Ecology’s Construction Stormwater Monitoring Manual provides guidance on representative sampling. Responsible Corporate Officer for the purpose of signatory authority means: (i) a president, secretary, treasurer, or vice-president of the corporation in charge of a principal business function, or any other person who performs similar policy- or decision-making functions for the corporation, or (ii) the manager of one or more manufacturing, production, or operating facilities, provided, the manager is authorized to make management decisions which govern the operation of the regulated facility including having the explicit or implicit duty of making major capital investment recommendations, and initiating and directing other comprehensive measures to assure long term environmental compliance with environmental laws and regulations; the manager can ensure that the necessary systems are established or actions taken to gather complete and accurate information for permit application requirements; and where authority to sign documents has been assigned or delegated to the manager in accordance with corporate procedures (40 CFR 122.22). Sanitary Sewer means a sewer which is designed to convey domestic wastewater. 182 of 347 Sediment means the fragmented material that originates from the weathering and erosion of rocks or unconsolidated deposits, and is transported by, suspended in, or deposited by water. Sedimentation means the depositing or formation of sediment. Sensitive Area means a waterbody, wetland, stream, aquifer recharge area, or channel migration zone. SEPA (State Environmental Policy Act) means the Washington State Law, RCW 43.21C.020, intended to prevent or eliminate damage to the environment. Significant Amount means an amount of a pollutant in a discharge that is amenable to available and reasonable methods of prevention or treatment; or an amount of a pollutant that has a reasonable potential to cause a violation of surface or groundwater quality or sediment management standards. Significant Concrete Work means greater than 1000 cubic yards placed or poured concrete or recycled concrete used over the life of a project. Significant Contributor of Pollutants means a facility determined by Ecology to be a contributor of a significant amount(s) of a pollutant(s) to waters of the State of Washington. Site means the land or water area where any "facility or activity" is physically located or conducted. Source Control BMPs means physical, structural or mechanical devices or facilities that are intended to prevent pollutants from entering stormwater. A few examples of source control BMPs are erosion control practices, maintenance of stormwater facilities, constructing roofs over storage and working areas, and directing wash water and similar discharges to the sanitary sewer or a dead end sump. Stabilization means the application of appropriate BMPs to prevent the erosion of soils, such as, temporary and permanent seeding, vegetative covers, mulching and matting, plastic covering and sodding. See also the definition of Erosion and Sediment Control BMPs. Storm Drain means any drain which drains directly into a storm sewer system, usually found along roadways or in parking lots. Storm Sewer System means a means a conveyance, or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, manmade channels, or storm drains designed or used for collecting or conveying stormwater. This does not include systems which are part of a combined sewer or Publicly Owned Treatment Works (POTW), as defined at 40 CFR 122.2. Stormwater means that portion of precipitation that does not naturally percolate into the ground or evaporate, but flows via overland flow, interflow, pipes, and other features of a stormwater drainage system into a defined surface waterbody, or a constructed infiltration facility. Stormwater Management Manual (SWMM) or Manual means the technical Manual published by Ecology for use by local governments that contain descriptions of and design criteria for BMPs to prevent, control, or treat pollutants in stormwater. Stormwater Pollution Prevention Plan (SWPPP) means a documented plan to implement measures to identify, prevent, and control the contamination of point source discharges of stormwater. 183 of 347 Surface Waters of the State includes lakes, rivers, ponds, streams, inland waters, salt waters, and all other surface waters and water courses within the jurisdiction of the state of Washington. Temporary Stabilization means the exposed ground surface has been covered with appropriate materials to provide temporary stabilization of the surface from water or wind erosion. Materials include, but are not limited to, mulch, riprap, erosion control mats or blankets and temporary cover crops. Seeding alone is not considered stabilization. Temporary stabilization is not a substitute for the more permanent “final stabilization.” Total Maximum Daily Load (TMDL) means a calculation of the maximum amount of a pollutant that a waterbody can receive and still meet state water quality standards. Percentages of the total maximum daily load are allocated to the various pollutant sources. A TMDL is the sum of the allowable loads of a single pollutant from all contributing point and nonpoint sources. The TMDL calculations must include a "margin of safety" to ensure that the waterbody can be protected in case there are unforeseen events or unknown sources of the pollutant. The calculation must also account for seasonable variation in water quality. Transfer of Coverage (TOC) means a request for transfer of coverage under this general permit as specified by Special Condition S2.A of this permit. Treatment BMPs means BMPs that are intended to remove pollutants from stormwater. A few examples of treatment BMPs are detention ponds, oil/water separators, biofiltration, and constructed wetlands. Transparency means a measurement of water clarity in centimeters (cm), using a 60 cm transparency tube. The transparency tube is used to estimate the relative clarity or transparency of water by noting the depth at which a black and white Secchi disc becomes visible when water is released from a value in the bottom of the tube. A transparency tube is sometimes referred to as a “turbidity tube.” Turbidity means the clarity of water expressed as nephelometric turbidity units (NTUs) and measured with a calibrated turbidimeter. Uncontaminated means free from any contaminant. See definition of “contaminant” and WAC 173-340-200. Upset means an exceptional incident in which there is unintentional and temporary noncompliance with technology-based permit effluent limitations because of factors beyond the reasonable control of the Permittee. An upset does not include noncompliance to the extent caused by operational error, improperly designed treatment facilities, inadequate treatment facilities, lack of preventive maintenance, or careless or improper operation. Waste Load Allocation (WLA) means the portion of a receiving water’s loading capacity that is allocated to one of its existing or future point sources of pollution. WLAs constitute a type of water quality based effluent limitation (40 CFR 130.2[h]). Water-Only Based Shaft Drilling is a shaft drilling process that uses water only and no additives are involved in the drilling of shafts for construction of building, road, or bridge foundations. Water Quality means the chemical, physical, and biological characteristics of water, usually with respect to its suitability for a particular purpose. Waters of the State includes those waters as defined as "waters of the United States" in 40 CFR Subpart 122.2 within the geographic boundaries of Washington State and "waters of the State" as defined in Chapter 90.48 RCW, which include lakes, rivers, ponds, streams, inland waters, underground waters, salt 184 of 347 waters, and all other surface waters and water courses within the jurisdiction of the state of Washington. Well means a bored, drilled or driven shaft, or dug hole whose depth is greater than the largest surface dimension. (See Injection Well.) Wheel Wash Wastewater means any water used in, or resulting from the operation of, a tire bath or wheel wash (BMP C106: Wheel Wash), or other structure or practice that uses water to physically remove mud and debris from vehicles leaving a construction site and prevent track-out onto roads. When stormwater comingles with wheel wash wastewater, the resulting water is considered wheel wash wastewater and must be managed according to Special Condition S9.D.9. 185 of 347 APPENDIX B – ACRONYMS AKART All Known, Available, and Reasonable Methods of Prevention, Control, and Treatment BMP Best Management Practice CESCL Certified Erosion and Sediment Control Lead CFR Code of Federal Regulations CKD Cement Kiln Dust cm Centimeters CPD Common Plan of Development CTB Cement-Treated Base CWA Clean Water Act DMR Discharge Monitoring Report EPA Environmental Protection Agency ERTS Environmental Report Tracking System ESC Erosion and Sediment Control FR Federal Register LID Low Impact Development NOI Notice of Intent NOT Notice of Termination NPDES National Pollutant Discharge Elimination System NTU Nephelometric Turbidity Unit RCW Revised Code of Washington SEPA State Environmental Policy Act SWMM Stormwater Management Manual SWPPP Stormwater Pollution Prevention Plan TMDL Total Maximum Daily Load UIC Underground Injection Control USC United States Code USEPA United States Environmental Protection Agency WAC Washington Administrative Code WQ Water Quality WWHM Western Washington Hydrology Model 186 of 347 Appendix C WWHM2012 Modeling Reports 187 of 347 WWHM2012 PROJECT REPORT 188 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:38 PM Page 2 General Model Information Project Name: Garden Ave Realignment_4.5bgs_22iph Site Name: Site Address: 31826 Garden Ave City:Auburn Report Date: 3/21/2023 Gage:Seatac Data Start: 1948/10/01 Data End: 2009/09/30 Timestep: 15 Minute Precip Scale: 1.000 Version Date: 2019/09/13 Version: 4.2.17 POC Thresholds Low Flow Threshold for POC1: 8 Percent of the 2 Year High Flow Threshold for POC1: 50 Year 189 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:38 PM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre A B, Forest, Flat 0.763 Pervious Total 0.763 Impervious Land Use acre Impervious Total 0 Basin Total 0.763 Element Flows To: Surface Interflow Groundwater 190 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:38 PM Page 4 Mitigated Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.028 Pervious Total 0.028 Impervious Land Use acre ROADS FLAT 0.735 Impervious Total 0.735 Basin Total 0.763 Element Flows To: Surface Interflow Groundwater Surface retention 1 191 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:38 PM Page 5 Routing Elements Predeveloped Routing 192 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:38 PM Page 6 Mitigated Routing Bioretention 1 Bottom Length: 150.38 ft. Bottom Width: 8.00 ft. Material thickness of first layer: 1.5 Material type for first layer: SMMWW 12 in/hr Material thickness of second layer: 0.5 Material type for second layer: GRAVEL Material thickness of third layer: 0 Material type for third layer: GRAVEL Infiltration On Infiltration rate:22 Infiltration safety factor:1 Total Volume Infiltrated (ac-ft.):117.709 Total Volume Through Riser (ac-ft.): 0 Total Volume Through Facility (ac-ft.): 117.709 Percent Infiltrated:100 Total Precip Applied to Facility:4.79 Total Evap From Facility:2.443 Underdrain not used Discharge Structure Riser Height:0.5 ft. Riser Diameter:12 in. Element Flows To: Outlet 1 Outlet 2 Bioretention Hydraulic Table Stage(feet) Area(ac.) Volume(ac-ft.) Discharge(cfs) Infilt(cfs) 0.0000 0.0276 0.0000 0.0000 0.0000 0.0330 0.0276 0.0004 0.0000 0.0000 0.0659 0.0276 0.0008 0.0000 0.0000 0.0989 0.0276 0.0012 0.0000 0.0000 0.1319 0.0276 0.0017 0.0000 0.0000 0.1648 0.0276 0.0021 0.0000 0.0000 0.1978 0.0276 0.0025 0.0000 0.0015 0.2308 0.0276 0.0029 0.0000 0.0023 0.2637 0.0276 0.0033 0.0000 0.0032 0.2967 0.0276 0.0037 0.0000 0.0044 0.3297 0.0276 0.0042 0.0000 0.0058 0.3626 0.0276 0.0046 0.0000 0.0074 0.3956 0.0276 0.0050 0.0000 0.0093 0.4286 0.0276 0.0054 0.0000 0.0115 0.4615 0.0276 0.0058 0.0000 0.0140 0.4945 0.0276 0.0062 0.0000 0.0167 0.5275 0.0276 0.0067 0.0000 0.0198 0.5604 0.0276 0.0071 0.0000 0.0233 0.5934 0.0276 0.0075 0.0000 0.0271 0.6264 0.0276 0.0079 0.0000 0.0312 0.6593 0.0276 0.0083 0.0000 0.0357 0.6923 0.0276 0.0087 0.0000 0.0406 0.7253 0.0276 0.0092 0.0000 0.0458 0.7582 0.0276 0.0096 0.0000 0.0515 0.7912 0.0276 0.0100 0.0000 0.0576 0.8242 0.0276 0.0104 0.0000 0.0640 193 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:38 PM Page 7 0.8571 0.0276 0.0108 0.0000 0.0709 0.8901 0.0276 0.0112 0.0000 0.0783 0.9231 0.0276 0.0117 0.0000 0.0861 0.9560 0.0276 0.0121 0.0000 0.0943 0.9890 0.0276 0.0125 0.0000 0.1030 1.0220 0.0276 0.0129 0.0000 0.1121 1.0549 0.0276 0.0133 0.0000 0.1218 1.0879 0.0276 0.0137 0.0000 0.1319 1.1209 0.0276 0.0142 0.0000 0.1410 1.1538 0.0276 0.0146 0.0000 0.1425 1.1868 0.0276 0.0150 0.0000 0.1536 1.2198 0.0276 0.0154 0.0000 0.1652 1.2527 0.0276 0.0158 0.0000 0.1773 1.2857 0.0276 0.0162 0.0000 0.1899 1.3187 0.0276 0.0167 0.0000 0.2031 1.3516 0.0276 0.0171 0.0000 0.2167 1.3846 0.0276 0.0175 0.0000 0.2309 1.4176 0.0276 0.0179 0.0000 0.2456 1.4505 0.0276 0.0183 0.0000 0.2609 1.4835 0.0276 0.0187 0.0000 0.2767 1.5165 0.0276 0.0191 0.0000 0.2930 1.5495 0.0276 0.0195 0.0000 0.3097 1.5824 0.0276 0.0199 0.0000 0.3267 1.6154 0.0276 0.0202 0.0000 0.4456 1.6484 0.0276 0.0206 0.0000 0.4456 1.6813 0.0276 0.0210 0.0000 0.4456 1.7143 0.0276 0.0214 0.0000 0.4456 1.7473 0.0276 0.0218 0.0000 0.4456 1.7802 0.0276 0.0221 0.0000 0.4456 1.8132 0.0276 0.0225 0.0000 0.4456 1.8462 0.0276 0.0229 0.0000 0.4456 1.8791 0.0276 0.0233 0.0000 0.4456 1.9121 0.0276 0.0236 0.0000 0.4456 1.9451 0.0276 0.0240 0.0000 0.4456 1.9780 0.0276 0.0244 0.0000 0.4456 2.0000 0.0276 0.0247 0.0000 0.4456 Bioretention Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)To Amended(cfs)Infilt(cfs) 2.0000 0.0276 0.0247 0.0000 0.3342 0.0000 2.0330 0.0276 0.0256 0.0000 0.3342 0.0000 2.0659 0.0276 0.0265 0.0000 0.3489 0.0000 2.0989 0.0276 0.0274 0.0000 0.3562 0.0000 2.1319 0.0276 0.0283 0.0000 0.3635 0.0000 2.1648 0.0276 0.0292 0.0000 0.3709 0.0000 2.1978 0.0276 0.0301 0.0000 0.3782 0.0000 2.2308 0.0276 0.0310 0.0000 0.3856 0.0000 2.2637 0.0276 0.0319 0.0000 0.3929 0.0000 2.2967 0.0276 0.0328 0.0000 0.4003 0.0000 2.3297 0.0276 0.0338 0.0000 0.4076 0.0000 2.3626 0.0276 0.0347 0.0000 0.4150 0.0000 2.3956 0.0276 0.0356 0.0000 0.4223 0.0000 2.4286 0.0276 0.0365 0.0000 0.4296 0.0000 2.4615 0.0276 0.0374 0.0000 0.4370 0.0000 2.4945 0.0276 0.0383 0.0000 0.4443 0.0000 2.5275 0.0276 0.0392 0.0483 0.4456 0.0000 2.5604 0.0276 0.0401 0.1574 0.4456 0.0000 2.5934 0.0276 0.0410 0.3014 0.4456 0.0000 194 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:39 PM Page 8 2.6264 0.0276 0.0420 0.4712 0.4456 0.0000 2.6593 0.0276 0.0429 0.6597 0.4456 0.0000 2.6923 0.0276 0.0438 0.8600 0.4456 0.0000 2.7253 0.0276 0.0447 1.0650 0.4456 0.0000 2.7582 0.0276 0.0456 1.2676 0.4456 0.0000 2.7912 0.0276 0.0465 1.4606 0.4456 0.0000 2.8242 0.0276 0.0474 1.6378 0.4456 0.0000 2.8571 0.0276 0.0483 1.7939 0.4456 0.0000 2.8901 0.0276 0.0492 1.9255 0.4456 0.0000 2.9231 0.0276 0.0501 2.0318 0.4456 0.0000 2.9560 0.0276 0.0511 2.1153 0.4456 0.0000 2.9890 0.0276 0.0520 2.1826 0.4456 0.0000 3.0000 0.0276 0.0523 2.2755 0.4456 0.0000 195 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:39 PM Page 9 Surface retention 1 Element Flows To: Outlet 1 Outlet 2 Bioretention 1 196 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:25:39 PM Page 10 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area: 0.763 Total Impervious Area: 0 Mitigated Landuse Totals for POC #1 Total Pervious Area: 0.028 Total Impervious Area: 0.735 Flow Frequency Method: Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.000647 5 year 0.00098 10 year 0.00125 25 year 0.001657 50 year 0.002011 100 year 0.002413 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0 5 year 0 10 year 0 25 year 0 50 year 0 100 year 0 Annual Peaks 197 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:28:40 PM Page 11 Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.001 0.000 1950 0.001 0.000 1951 0.001 0.000 1952 0.001 0.000 1953 0.001 0.000 1954 0.001 0.000 1955 0.001 0.000 1956 0.001 0.000 1957 0.001 0.000 1958 0.001 0.000 1959 0.001 0.000 1960 0.001 0.000 1961 0.001 0.000 1962 0.001 0.000 1963 0.001 0.000 1964 0.001 0.000 1965 0.001 0.000 1966 0.001 0.000 1967 0.001 0.000 1968 0.001 0.000 1969 0.001 0.000 1970 0.001 0.000 1971 0.001 0.000 1972 0.003 0.000 1973 0.001 0.000 1974 0.001 0.000 1975 0.001 0.000 1976 0.001 0.000 1977 0.000 0.000 1978 0.001 0.000 1979 0.001 0.000 1980 0.001 0.000 1981 0.001 0.000 1982 0.001 0.000 1983 0.001 0.000 1984 0.001 0.000 1985 0.001 0.000 1986 0.001 0.000 1987 0.001 0.000 1988 0.001 0.000 1989 0.001 0.000 1990 0.001 0.000 1991 0.001 0.000 1992 0.001 0.000 1993 0.000 0.000 1994 0.001 0.000 1995 0.001 0.000 1996 0.004 0.000 1997 0.001 0.000 1998 0.001 0.000 1999 0.001 0.000 2000 0.001 0.000 2001 0.001 0.000 2002 0.001 0.000 2003 0.001 0.000 2004 0.001 0.000 198 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:28:40 PM Page 12 2005 0.001 0.000 2006 0.001 0.000 2007 0.006 0.000 2008 0.001 0.000 2009 0.001 0.000 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0063 0.0000 2 0.0043 0.0000 3 0.0032 0.0000 4 0.0012 0.0000 5 0.0011 0.0000 6 0.0010 0.0000 7 0.0010 0.0000 8 0.0006 0.0000 9 0.0006 0.0000 10 0.0006 0.0000 11 0.0006 0.0000 12 0.0006 0.0000 13 0.0006 0.0000 14 0.0006 0.0000 15 0.0006 0.0000 16 0.0006 0.0000 17 0.0006 0.0000 18 0.0006 0.0000 19 0.0006 0.0000 20 0.0006 0.0000 21 0.0006 0.0000 22 0.0006 0.0000 23 0.0006 0.0000 24 0.0006 0.0000 25 0.0006 0.0000 26 0.0006 0.0000 27 0.0006 0.0000 28 0.0006 0.0000 29 0.0006 0.0000 30 0.0006 0.0000 31 0.0006 0.0000 32 0.0006 0.0000 33 0.0006 0.0000 34 0.0006 0.0000 35 0.0006 0.0000 36 0.0006 0.0000 37 0.0006 0.0000 38 0.0006 0.0000 39 0.0006 0.0000 40 0.0006 0.0000 41 0.0006 0.0000 42 0.0006 0.0000 43 0.0006 0.0000 44 0.0006 0.0000 45 0.0006 0.0000 46 0.0006 0.0000 47 0.0006 0.0000 48 0.0006 0.0000 49 0.0006 0.0000 199 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:28:40 PM Page 13 50 0.0006 0.0000 51 0.0006 0.0000 52 0.0006 0.0000 53 0.0006 0.0000 54 0.0006 0.0000 55 0.0006 0.0000 56 0.0006 0.0000 57 0.0006 0.0000 58 0.0005 0.0000 59 0.0005 0.0000 60 0.0005 0.0000 61 0.0005 0.0000 200 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:28:40 PM Page 14 LID Duration Flows The Facility PASSED Flow(cfs) Predev Mit Percentage Pass/Fail 0.0001 22373 0 0 Pass 0.0001 21365 0 0 Pass 0.0001 20529 0 0 Pass 0.0001 20052 0 0 Pass 0.0001 19327 0 0 Pass 0.0001 18486 0 0 Pass 0.0001 17836 0 0 Pass 0.0001 17410 0 0 Pass 0.0001 16848 0 0 Pass 0.0001 16322 0 0 Pass 0.0001 15796 0 0 Pass 0.0001 15471 0 0 Pass 0.0001 15043 0 0 Pass 0.0001 14598 0 0 Pass 0.0001 14142 0 0 Pass 0.0001 13854 0 0 Pass 0.0001 13466 0 0 Pass 0.0001 13060 0 0 Pass 0.0001 12718 0 0 Pass 0.0001 12547 0 0 Pass 0.0001 12226 0 0 Pass 0.0001 11952 0 0 Pass 0.0001 11618 0 0 Pass 0.0001 11434 0 0 Pass 0.0001 11137 0 0 Pass 0.0001 10855 0 0 Pass 0.0001 10555 0 0 Pass 0.0001 10299 0 0 Pass 0.0001 10066 0 0 Pass 0.0001 9877 0 0 Pass 0.0001 9685 0 0 Pass 0.0001 9548 0 0 Pass 0.0001 9347 0 0 Pass 0.0001 9152 0 0 Pass 0.0001 8953 0 0 Pass 0.0001 8806 0 0 Pass 0.0002 8609 0 0 Pass 0.0002 8442 0 0 Pass 0.0002 8284 0 0 Pass 0.0002 8164 0 0 Pass 0.0002 8027 0 0 Pass 0.0002 7888 0 0 Pass 0.0002 7762 0 0 Pass 0.0002 7655 0 0 Pass 0.0002 7497 0 0 Pass 0.0002 7360 0 0 Pass 0.0002 7232 0 0 Pass 0.0002 7131 0 0 Pass 0.0002 6953 0 0 Pass 0.0002 6844 0 0 Pass 0.0002 6710 0 0 Pass 0.0002 6628 0 0 Pass 0.0002 6509 0 0 Pass 201 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:28:40 PM Page 15 0.0002 6412 0 0 Pass 0.0002 6344 0 0 Pass 0.0002 6233 0 0 Pass 0.0002 6113 0 0 Pass 0.0002 6012 0 0 Pass 0.0002 5916 0 0 Pass 0.0002 5794 0 0 Pass 0.0002 5655 0 0 Pass 0.0002 5542 0 0 Pass 0.0002 5471 0 0 Pass 0.0002 5364 0 0 Pass 0.0002 5253 0 0 Pass 0.0002 5165 0 0 Pass 0.0002 5110 0 0 Pass 0.0002 5033 0 0 Pass 0.0002 4958 0 0 Pass 0.0002 4875 0 0 Pass 0.0002 4834 0 0 Pass 0.0002 4742 0 0 Pass 0.0002 4667 0 0 Pass 0.0003 4562 0 0 Pass 0.0003 4507 0 0 Pass 0.0003 4419 0 0 Pass 0.0003 4327 0 0 Pass 0.0003 4220 0 0 Pass 0.0003 4158 0 0 Pass 0.0003 4085 0 0 Pass 0.0003 4023 0 0 Pass 0.0003 3955 0 0 Pass 0.0003 3916 0 0 Pass 0.0003 3850 0 0 Pass 0.0003 3773 0 0 Pass 0.0003 3715 0 0 Pass 0.0003 3681 0 0 Pass 0.0003 3632 0 0 Pass 0.0003 3576 0 0 Pass 0.0003 3514 0 0 Pass 0.0003 3480 0 0 Pass 0.0003 3422 0 0 Pass 0.0003 3369 0 0 Pass 0.0003 3315 0 0 Pass 0.0003 3279 0 0 Pass 0.0003 3221 0 0 Pass 0.0003 3168 0 0 Pass 0.0003 3118 0 0 Pass 0.0003 3089 0 0 Pass 0.0003 3050 0 0 Pass 202 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:29:14 PM Page 16 Duration Flows The Facility PASSED Flow(cfs) Predev Mit Percentage Pass/Fail 0.0001 22373 0 0 Pass 0.0001 17239 0 0 Pass 0.0001 13984 0 0 Pass 0.0001 11717 0 0 Pass 0.0001 9933 0 0 Pass 0.0002 8609 0 0 Pass 0.0002 7595 0 0 Pass 0.0002 6663 0 0 Pass 0.0002 5916 0 0 Pass 0.0002 5189 0 0 Pass 0.0002 4667 0 0 Pass 0.0003 4057 0 0 Pass 0.0003 3651 0 0 Pass 0.0003 3279 0 0 Pass 0.0003 2947 0 0 Pass 0.0003 2573 0 0 Pass 0.0004 2248 0 0 Pass 0.0004 1955 0 0 Pass 0.0004 1707 0 0 Pass 0.0004 1466 0 0 Pass 0.0004 1291 0 0 Pass 0.0005 1121 0 0 Pass 0.0005 915 0 0 Pass 0.0005 729 0 0 Pass 0.0005 563 0 0 Pass 0.0005 435 0 0 Pass 0.0006 323 0 0 Pass 0.0006 210 0 0 Pass 0.0006 75 0 0 Pass 0.0006 26 0 0 Pass 0.0006 26 0 0 Pass 0.0007 26 0 0 Pass 0.0007 25 0 0 Pass 0.0007 25 0 0 Pass 0.0007 24 0 0 Pass 0.0007 23 0 0 Pass 0.0008 23 0 0 Pass 0.0008 23 0 0 Pass 0.0008 22 0 0 Pass 0.0008 22 0 0 Pass 0.0008 21 0 0 Pass 0.0009 21 0 0 Pass 0.0009 21 0 0 Pass 0.0009 21 0 0 Pass 0.0009 19 0 0 Pass 0.0009 19 0 0 Pass 0.0010 18 0 0 Pass 0.0010 18 0 0 Pass 0.0010 16 0 0 Pass 0.0010 16 0 0 Pass 0.0010 16 0 0 Pass 0.0011 16 0 0 Pass 0.0011 15 0 0 Pass 203 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:29:14 PM Page 17 0.0011 15 0 0 Pass 0.0011 15 0 0 Pass 0.0011 14 0 0 Pass 0.0012 13 0 0 Pass 0.0012 13 0 0 Pass 0.0012 13 0 0 Pass 0.0012 13 0 0 Pass 0.0012 13 0 0 Pass 0.0013 12 0 0 Pass 0.0013 12 0 0 Pass 0.0013 11 0 0 Pass 0.0013 11 0 0 Pass 0.0013 11 0 0 Pass 0.0014 11 0 0 Pass 0.0014 10 0 0 Pass 0.0014 10 0 0 Pass 0.0014 9 0 0 Pass 0.0014 9 0 0 Pass 0.0015 9 0 0 Pass 0.0015 9 0 0 Pass 0.0015 8 0 0 Pass 0.0015 8 0 0 Pass 0.0015 8 0 0 Pass 0.0016 8 0 0 Pass 0.0016 8 0 0 Pass 0.0016 8 0 0 Pass 0.0016 8 0 0 Pass 0.0016 8 0 0 Pass 0.0017 8 0 0 Pass 0.0017 8 0 0 Pass 0.0017 8 0 0 Pass 0.0017 8 0 0 Pass 0.0017 8 0 0 Pass 0.0018 8 0 0 Pass 0.0018 8 0 0 Pass 0.0018 8 0 0 Pass 0.0018 8 0 0 Pass 0.0018 8 0 0 Pass 0.0019 8 0 0 Pass 0.0019 8 0 0 Pass 0.0019 8 0 0 Pass 0.0019 8 0 0 Pass 0.0019 8 0 0 Pass 0.0020 8 0 0 Pass 0.0020 8 0 0 Pass 0.0020 8 0 0 Pass 0.0020 8 0 0 Pass 204 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:29:14 PM Page 18 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume: 0 acre-feet On-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. Off-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. 205 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:29:14 PM Page 19 LID Report 206 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:29:54 PM Page 20 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. 207 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:29:54 PM Page 21 Appendix Predeveloped Schematic 208 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:21 PM Page 22 Mitigated Schematic 209 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:51 PM Page 23 Predeveloped UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Garden Ave Realignment_4.5bgs_22iph.wdm MESSU 25 PreGarden Ave Realignment_4.5bgs_22iph.MES 27 PreGarden Ave Realignment_4.5bgs_22iph.L61 28 PreGarden Ave Realignment_4.5bgs_22iph.L62 30 POCGarden Ave Realignment_4.5bgs_22iph1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 1 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Basin 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 A/B, Forest, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 1 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 1 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO 210 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:51 PM Page 24 PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 1 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 1 0 5 2 400 0.05 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 1 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 1 0.2 0.5 0.35 0 0.7 0.7 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 1 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC END IWAT-PARM2 IWAT-PARM3 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS END IWAT-STATE1 211 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 25 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 1 0.763 COPY 501 12 PERLND 1 0.763 COPY 501 13 ******Routing****** END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC 212 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 26 WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP END EXT SOURCES EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** COPY 501 OUTPUT MEAN 1 1 48.4 WDM 501 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 13 PERLND PWATER IFWO 0.083333 COPY INPUT MEAN END MASS-LINK 13 END MASS-LINK END RUN 213 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 27 Mitigated UCI File RUN GLOBAL WWHM4 model simulation START 1948 10 01 END 2009 09 30 RUN INTERP OUTPUT LEVEL 3 0 RESUME 0 RUN 1 UNIT SYSTEM 1 END GLOBAL FILES <File> <Un#> <-----------File Name------------------------------>*** <-ID-> *** WDM 26 Garden Ave Realignment_4.5bgs_22iph.wdm MESSU 25 MitGarden Ave Realignment_4.5bgs_22iph.MES 27 MitGarden Ave Realignment_4.5bgs_22iph.L61 28 MitGarden Ave Realignment_4.5bgs_22iph.L62 30 POCGarden Ave Realignment_4.5bgs_22iph1.dat END FILES OPN SEQUENCE INGRP INDELT 00:15 PERLND 7 IMPLND 1 RCHRES 1 RCHRES 2 COPY 1 COPY 501 DISPLY 1 END INGRP END OPN SEQUENCE DISPLY DISPLY-INFO1 # - #<----------Title----------->***TRAN PIVL DIG1 FIL1 PYR DIG2 FIL2 YRND 1 Surface retention 1 MAX 1 2 30 9 END DISPLY-INFO1 END DISPLY COPY TIMESERIES # - # NPT NMN *** 1 1 1 501 1 1 END TIMESERIES END COPY GENER OPCODE # # OPCD *** END OPCODE PARM # # K *** END PARM END GENER PERLND GEN-INFO <PLS ><-------Name------->NBLKS Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 7 A/B, Lawn, Flat 1 1 1 1 27 0 END GEN-INFO *** Section PWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC *** 7 0 0 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ***************************** PIVL PYR 214 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 28 # - # ATMP SNOW PWAT SED PST PWG PQAL MSTL PEST NITR PHOS TRAC ********* 7 0 0 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO PWAT-PARM1 <PLS > PWATER variable monthly parameter value flags *** # - # CSNO RTOP UZFG VCS VUZ VNN VIFW VIRC VLE INFC HWT *** 7 0 0 0 0 0 0 0 0 0 0 0 END PWAT-PARM1 PWAT-PARM2 <PLS > PWATER input info: Part 2 *** # - # ***FOREST LZSN INFILT LSUR SLSUR KVARY AGWRC 7 0 5 0.8 400 0.05 0.3 0.996 END PWAT-PARM2 PWAT-PARM3 <PLS > PWATER input info: Part 3 *** # - # ***PETMAX PETMIN INFEXP INFILD DEEPFR BASETP AGWETP 7 0 0 2 2 0 0 0 END PWAT-PARM3 PWAT-PARM4 <PLS > PWATER input info: Part 4 *** # - # CEPSC UZSN NSUR INTFW IRC LZETP *** 7 0.1 0.5 0.25 0 0.7 0.25 END PWAT-PARM4 PWAT-STATE1 <PLS > *** Initial conditions at start of simulation ran from 1990 to end of 1992 (pat 1-11-95) RUN 21 *** # - # *** CEPS SURS UZS IFWS LZS AGWS GWVS 7 0 0 0 0 3 1 0 END PWAT-STATE1 END PERLND IMPLND GEN-INFO <PLS ><-------Name-------> Unit-systems Printer *** # - # User t-series Engl Metr *** in out *** 1 ROADS/FLAT 1 1 1 27 0 END GEN-INFO *** Section IWATER*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # ATMP SNOW IWAT SLD IWG IQAL *** 1 0 0 1 0 0 0 END ACTIVITY PRINT-INFO <ILS > ******** Print-flags ******** PIVL PYR # - # ATMP SNOW IWAT SLD IWG IQAL ********* 1 0 0 4 0 0 0 1 9 END PRINT-INFO IWAT-PARM1 <PLS > IWATER variable monthly parameter value flags *** # - # CSNO RTOP VRS VNN RTLI *** 1 0 0 0 0 0 END IWAT-PARM1 IWAT-PARM2 <PLS > IWATER input info: Part 2 *** # - # *** LSUR SLSUR NSUR RETSC 1 400 0.01 0.1 0.1 END IWAT-PARM2 IWAT-PARM3 215 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 29 <PLS > IWATER input info: Part 3 *** # - # ***PETMAX PETMIN 1 0 0 END IWAT-PARM3 IWAT-STATE1 <PLS > *** Initial conditions at start of simulation # - # *** RETS SURS 1 0 0 END IWAT-STATE1 END IMPLND SCHEMATIC <-Source-> <--Area--> <-Target-> MBLK *** <Name> # <-factor-> <Name> # Tbl# *** Basin 1*** PERLND 7 0.028 RCHRES 1 2 IMPLND 1 0.735 RCHRES 1 5 ******Routing****** PERLND 7 0.028 COPY 1 12 IMPLND 1 0.735 COPY 1 15 RCHRES 1 1 RCHRES 2 8 RCHRES 2 1 COPY 501 17 RCHRES 1 1 COPY 501 17 END SCHEMATIC NETWORK <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** COPY 501 OUTPUT MEAN 1 1 48.4 DISPLY 1 INPUT TIMSER 1 <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # #<-factor->strg <Name> # # <Name> # # *** END NETWORK RCHRES GEN-INFO RCHRES Name Nexits Unit Systems Printer *** # - #<------------------><---> User T-series Engl Metr LKFG *** in out *** 1 Surface retentio-008 2 1 1 1 28 0 1 2 Bioretention 1 2 1 1 1 28 0 1 END GEN-INFO *** Section RCHRES*** ACTIVITY <PLS > ************* Active Sections ***************************** # - # HYFG ADFG CNFG HTFG SDFG GQFG OXFG NUFG PKFG PHFG *** 1 1 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 0 0 0 0 END ACTIVITY PRINT-INFO <PLS > ***************** Print-flags ******************* PIVL PYR # - # HYDR ADCA CONS HEAT SED GQL OXRX NUTR PLNK PHCB PIVL PYR ********* 1 4 0 0 0 0 0 0 0 0 0 1 9 2 4 0 0 0 0 0 0 0 0 0 1 9 END PRINT-INFO HYDR-PARM1 RCHRES Flags for each HYDR Section *** # - # VC A1 A2 A3 ODFVFG for each *** ODGTFG for each FUNCT for each FG FG FG FG possible exit *** possible exit possible exit * * * * * * * * * * * * * * *** 1 0 1 0 0 4 5 0 0 0 0 0 0 0 0 2 2 2 2 2 2 0 1 0 0 4 5 0 0 0 0 0 0 0 0 2 2 2 2 2 216 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 30 END HYDR-PARM1 HYDR-PARM2 # - # FTABNO LEN DELTH STCOR KS DB50 *** <------><--------><--------><--------><--------><--------><--------> *** 1 1 0.01 0.0 0.0 0.0 0.0 2 2 0.03 0.0 0.0 0.0 0.0 END HYDR-PARM2 HYDR-INIT RCHRES Initial conditions for each HYDR section *** # - # *** VOL Initial value of COLIND Initial value of OUTDGT *** ac-ft for each possible exit for each possible exit <------><--------> <---><---><---><---><---> *** <---><---><---><---><---> 1 0 4.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2 0 4.0 5.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 END HYDR-INIT END RCHRES SPEC-ACTIONS END SPEC-ACTIONS FTABLES FTABLE 2 62 5 Depth Area Volume Outflow1 Outflow2 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.027617 0.000000 0.000000 0.000000 0.032967 0.027617 0.000416 0.000000 0.000000 0.065934 0.027617 0.000833 0.000000 0.000000 0.098901 0.027617 0.001249 0.000000 0.000000 0.131868 0.027617 0.001665 0.000000 0.000000 0.164835 0.027617 0.002082 0.000000 0.000000 0.197802 0.027617 0.002498 0.000000 0.001524 0.230769 0.027617 0.002914 0.000000 0.002267 0.263736 0.027617 0.003331 0.000000 0.003207 0.296703 0.027617 0.003747 0.000000 0.004362 0.329670 0.027617 0.004164 0.000000 0.005752 0.362637 0.027617 0.004580 0.000000 0.007391 0.395604 0.027617 0.004996 0.000000 0.009295 0.428571 0.027617 0.005413 0.000000 0.011480 0.461538 0.027617 0.005829 0.000000 0.013958 0.494505 0.027617 0.006245 0.000000 0.016743 0.527473 0.027617 0.006662 0.000000 0.019848 0.560440 0.027617 0.007078 0.000000 0.023285 0.593407 0.027617 0.007494 0.000000 0.027065 0.626374 0.027617 0.007911 0.000000 0.031199 0.659341 0.027617 0.008327 0.000000 0.035699 0.692308 0.027617 0.008743 0.000000 0.040576 0.725275 0.027617 0.009160 0.000000 0.045838 0.758242 0.027617 0.009576 0.000000 0.051496 0.791209 0.027617 0.009992 0.000000 0.057561 0.824176 0.027617 0.010409 0.000000 0.064040 0.857143 0.027617 0.010825 0.000000 0.070944 0.890110 0.027617 0.011241 0.000000 0.078281 0.923077 0.027617 0.011658 0.000000 0.086061 0.956044 0.027617 0.012074 0.000000 0.094290 0.989011 0.027617 0.012491 0.000000 0.102979 1.021978 0.027617 0.012907 0.000000 0.112134 1.054945 0.027617 0.013323 0.000000 0.121763 1.087912 0.027617 0.013740 0.000000 0.131875 1.120879 0.027617 0.014156 0.000000 0.140992 1.153846 0.027617 0.014572 0.000000 0.142476 1.186813 0.027617 0.014989 0.000000 0.153573 1.219780 0.027617 0.015405 0.000000 0.165174 1.252747 0.027617 0.015821 0.000000 0.177283 1.285714 0.027617 0.016238 0.000000 0.189908 1.318681 0.027617 0.016654 0.000000 0.203053 1.351648 0.027617 0.017070 0.000000 0.216723 1.384615 0.027617 0.017487 0.000000 0.230921 1.417582 0.027617 0.017903 0.000000 0.245649 1.450549 0.027617 0.018319 0.000000 0.260906 217 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 31 1.483516 0.027617 0.018736 0.000000 0.276685 1.516484 0.027617 0.019114 0.000000 0.292968 1.549451 0.027617 0.019491 0.000000 0.309709 1.582418 0.027617 0.019869 0.000000 0.326713 1.615385 0.027617 0.020247 0.000000 0.445556 1.648352 0.027617 0.020625 0.000000 0.445556 1.681319 0.027617 0.021003 0.000000 0.445556 1.714286 0.027617 0.021381 0.000000 0.445556 1.747253 0.027617 0.021758 0.000000 0.445556 1.780220 0.027617 0.022136 0.000000 0.445556 1.813187 0.027617 0.022514 0.000000 0.445556 1.846154 0.027617 0.022892 0.000000 0.445556 1.879121 0.027617 0.023270 0.000000 0.445556 1.912088 0.027617 0.023648 0.000000 0.445556 1.945055 0.027617 0.024025 0.000000 0.445556 1.978022 0.027617 0.024403 0.000000 0.445556 2.000000 0.027617 0.033861 0.000000 0.445556 END FTABLE 2 FTABLE 1 32 5 Depth Area Volume Outflow1 Outflow2 Velocity Travel Time*** (ft) (acres) (acre-ft) (cfs) (cfs) (ft/sec) (Minutes)*** 0.000000 0.027617 0.000000 0.000000 0.000000 0.032967 0.027617 0.000910 0.000000 0.334167 0.065934 0.027617 0.001821 0.000000 0.348856 0.098901 0.027617 0.002731 0.000000 0.356200 0.131868 0.027617 0.003642 0.000000 0.363544 0.164835 0.027617 0.004552 0.000000 0.370889 0.197802 0.027617 0.005463 0.000000 0.378233 0.230769 0.027617 0.006373 0.000000 0.385577 0.263736 0.027617 0.007284 0.000000 0.392922 0.296703 0.027617 0.008194 0.000000 0.400266 0.329670 0.027617 0.009105 0.000000 0.407610 0.362637 0.027617 0.010015 0.000000 0.414955 0.395604 0.027617 0.010925 0.000000 0.422299 0.428571 0.027617 0.011836 0.000000 0.429643 0.461538 0.027617 0.012746 0.000000 0.436988 0.494505 0.027617 0.013657 0.000000 0.444332 0.527473 0.027617 0.014567 0.048301 0.445556 0.560440 0.027617 0.015478 0.157374 0.445556 0.593407 0.027617 0.016388 0.301385 0.445556 0.626374 0.027617 0.017299 0.471194 0.445556 0.659341 0.027617 0.018209 0.659695 0.445556 0.692308 0.027617 0.019120 0.859995 0.445556 0.725275 0.027617 0.020030 1.065020 0.445556 0.758242 0.027617 0.020940 1.267570 0.445556 0.791209 0.027617 0.021851 1.460630 0.445556 0.824176 0.027617 0.022761 1.637810 0.445556 0.857143 0.027617 0.023672 1.793902 0.445556 0.890110 0.027617 0.024582 1.925525 0.445556 0.923077 0.027617 0.025493 2.031838 0.445556 0.956044 0.027617 0.026403 2.115324 0.445556 0.989011 0.027617 0.027314 2.182633 0.445556 1.000000 0.027617 0.027617 2.275546 0.445556 END FTABLE 1 END FTABLES EXT SOURCES <-Volume-> <Member> SsysSgap<--Mult-->Tran <-Target vols> <-Grp> <-Member-> *** <Name> # <Name> # tem strg<-factor->strg <Name> # # <Name> # # *** WDM 2 PREC ENGL 1 PERLND 1 999 EXTNL PREC WDM 2 PREC ENGL 1 IMPLND 1 999 EXTNL PREC WDM 1 EVAP ENGL 0.76 PERLND 1 999 EXTNL PETINP WDM 1 EVAP ENGL 0.76 IMPLND 1 999 EXTNL PETINP WDM 2 PREC ENGL 1 RCHRES 1 EXTNL PREC WDM 1 EVAP ENGL 0.5 RCHRES 1 EXTNL POTEV WDM 1 EVAP ENGL 0.76 RCHRES 2 EXTNL POTEV END EXT SOURCES 218 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 32 EXT TARGETS <-Volume-> <-Grp> <-Member-><--Mult-->Tran <-Volume-> <Member> Tsys Tgap Amd *** <Name> # <Name> # #<-factor->strg <Name> # <Name> tem strg strg*** RCHRES 2 HYDR RO 1 1 1 WDM 1000 FLOW ENGL REPL RCHRES 2 HYDR O 1 1 1 WDM 1004 FLOW ENGL REPL RCHRES 2 HYDR O 2 1 1 WDM 1005 FLOW ENGL REPL RCHRES 2 HYDR STAGE 1 1 1 WDM 1001 STAG ENGL REPL RCHRES 1 HYDR STAGE 1 1 1 WDM 1002 STAG ENGL REPL RCHRES 1 HYDR O 1 1 1 WDM 1003 FLOW ENGL REPL COPY 1 OUTPUT MEAN 1 1 48.4 WDM 701 FLOW ENGL REPL COPY 501 OUTPUT MEAN 1 1 48.4 WDM 801 FLOW ENGL REPL END EXT TARGETS MASS-LINK <Volume> <-Grp> <-Member-><--Mult--> <Target> <-Grp> <-Member->*** <Name> <Name> # #<-factor-> <Name> <Name> # #*** MASS-LINK 2 PERLND PWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 2 MASS-LINK 5 IMPLND IWATER SURO 0.083333 RCHRES INFLOW IVOL END MASS-LINK 5 MASS-LINK 8 RCHRES OFLOW OVOL 2 RCHRES INFLOW IVOL END MASS-LINK 8 MASS-LINK 12 PERLND PWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 12 MASS-LINK 15 IMPLND IWATER SURO 0.083333 COPY INPUT MEAN END MASS-LINK 15 MASS-LINK 17 RCHRES OFLOW OVOL 1 COPY INPUT MEAN END MASS-LINK 17 END MASS-LINK END RUN 219 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:52 PM Page 33 Predeveloped HSPF Message File 220 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:53 PM Page 34 Mitigated HSPF Message File 221 of 347 DRAFTGarden Ave Realignment_4.5bgs_22iph 3/21/2023 1:30:53 PM Page 35 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2023; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com 222 of 347 WWHM2012 PROJECT REPORT 223 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:24 PM Page 2 General Model Information Project Name: Garden Ave Realignment_6.5bgs_282iph Site Name: Site Address: 31826 Garden Ave City:Auburn Report Date: 3/16/2023 Gage:Seatac Data Start: 1948/10/01 Data End: 2009/09/30 Timestep: 15 Minute Precip Scale: 1.000 Version Date: 2019/09/13 Version: 4.2.17 POC Thresholds Low Flow Threshold for POC1: 8 Percent of the 2 Year High Flow Threshold for POC1: 50 Year 224 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:24 PM Page 3 Landuse Basin Data Predeveloped Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre A B, Forest, Flat 0.791 Pervious Total 0.791 Impervious Land Use acre Impervious Total 0 Basin Total 0.791 Element Flows To: Surface Interflow Groundwater 225 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:24 PM Page 4 Mitigated Land Use Basin 1 Bypass:No GroundWater:No Pervious Land Use acre A B, Lawn, Flat 0.028 Pervious Total 0.028 Impervious Land Use acre ROADS FLAT 0.763 Impervious Total 0.763 Basin Total 0.791 Element Flows To: Surface Interflow Groundwater Surface retention 1 226 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:24 PM Page 5 Routing Elements Predeveloped Routing 227 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:25 PM Page 6 Mitigated Routing Bioretention 1 Bottom Length: 112.00 ft. Bottom Width: 8.00 ft. Material thickness of first layer: 1.5 Material type for first layer: SMMWW 12 in/hr Material thickness of second layer: 2.5 Material type for second layer: Sand Material thickness of third layer: 0.5 Material type for third layer: GRAVEL Infiltration On Infiltration rate:282 Infiltration safety factor:1 Total Volume Infiltrated (ac-ft.):121.126 Total Volume Through Riser (ac-ft.): 0.006 Total Volume Through Facility (ac-ft.): 121.132 Percent Infiltrated:100 Total Precip Applied to Facility:3.573 Total Evap From Facility:2.291 Underdrain not used Discharge Structure Riser Height:0.5 ft. Riser Diameter:12 in. Element Flows To: Outlet 1 Outlet 2 Bioretention Hydraulic Table Stage(feet) Area(ac.) Volume(ac-ft.) Discharge(cfs) Infilt(cfs) 0.0000 0.0206 0.0000 0.0000 0.0000 0.0604 0.0206 0.0006 0.0000 0.0000 0.1209 0.0206 0.0011 0.0000 0.0000 0.1813 0.0206 0.0017 0.0000 0.0000 0.2418 0.0206 0.0023 0.0000 0.0000 0.3022 0.0206 0.0028 0.0000 0.0000 0.3626 0.0206 0.0034 0.0000 0.0000 0.4231 0.0206 0.0040 0.0000 0.0005 0.4835 0.0206 0.0045 0.0000 0.0008 0.5440 0.0206 0.0051 0.0000 0.0013 0.6044 0.0206 0.0057 0.0000 0.0019 0.6648 0.0206 0.0063 0.0000 0.0020 0.7253 0.0206 0.0068 0.0000 0.0027 0.7857 0.0206 0.0074 0.0000 0.0036 0.8462 0.0206 0.0080 0.0000 0.0036 0.9066 0.0206 0.0085 0.0000 0.0048 0.9670 0.0206 0.0091 0.0000 0.0057 1.0275 0.0206 0.0097 0.0000 0.0061 1.0879 0.0206 0.0102 0.0000 0.0077 1.1484 0.0206 0.0108 0.0000 0.0086 1.2088 0.0206 0.0114 0.0000 0.0094 1.2692 0.0206 0.0119 0.0000 0.0114 1.3297 0.0206 0.0125 0.0000 0.0121 1.3901 0.0206 0.0131 0.0000 0.0136 1.4505 0.0206 0.0136 0.0000 0.0161 1.5110 0.0206 0.0141 0.0000 0.0165 228 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:25 PM Page 7 1.5714 0.0206 0.0146 0.0000 0.0188 1.6319 0.0206 0.0151 0.0000 0.0217 1.6923 0.0206 0.0156 0.0000 0.0218 1.7527 0.0206 0.0161 0.0000 0.0250 1.8132 0.0206 0.0166 0.0000 0.0278 1.8736 0.0206 0.0171 0.0000 0.0285 1.9341 0.0206 0.0176 0.0000 0.0323 1.9945 0.0206 0.0181 0.0000 0.0348 2.0549 0.0206 0.0186 0.0000 0.0364 2.1154 0.0206 0.0191 0.0000 0.0408 2.1758 0.0206 0.0196 0.0000 0.0429 2.2363 0.0206 0.0201 0.0000 0.0455 2.2967 0.0206 0.0206 0.0000 0.0505 2.3571 0.0206 0.0211 0.0000 0.0520 2.4176 0.0206 0.0216 0.0000 0.0559 2.4780 0.0206 0.0221 0.0000 0.0615 2.5385 0.0206 0.0226 0.0000 0.0621 2.5989 0.0206 0.0231 0.0000 0.0675 2.6593 0.0206 0.0236 0.0000 0.0734 2.7198 0.0206 0.0241 0.0000 0.0738 2.7802 0.0206 0.0246 0.0000 0.0805 2.8407 0.0206 0.0251 0.0000 0.0859 2.9011 0.0206 0.0256 0.0000 0.0875 2.9615 0.0206 0.0261 0.0000 0.0878 3.0220 0.0206 0.0266 0.0000 0.0949 3.0824 0.0206 0.0271 0.0000 0.0995 3.1429 0.0206 0.0276 0.0000 0.1026 3.2033 0.0206 0.0281 0.0000 0.1107 3.2637 0.0206 0.0286 0.0000 0.1144 3.3242 0.0206 0.0291 0.0000 0.1192 3.3846 0.0206 0.0296 0.0000 0.1280 3.4451 0.0206 0.0301 0.0000 0.1305 3.5055 0.0206 0.0306 0.0000 0.1372 3.5659 0.0206 0.0310 0.0000 0.1468 3.6264 0.0206 0.0315 0.0000 0.1479 3.6868 0.0206 0.0320 0.0000 0.1568 3.7473 0.0206 0.0325 0.0000 0.1667 3.8077 0.0206 0.0330 0.0000 0.1671 3.8681 0.0206 0.0335 0.0000 0.1778 3.9286 0.0206 0.0340 0.0000 0.1867 3.9890 0.0206 0.0345 0.0000 0.1888 4.0495 0.0206 0.0350 0.0000 0.1924 4.1099 0.0206 0.0356 0.0000 0.1924 4.1703 0.0206 0.0361 0.0000 0.3463 4.2308 0.0206 0.0366 0.0000 0.3463 4.2912 0.0206 0.0371 0.0000 0.3463 4.3516 0.0206 0.0376 0.0000 0.3463 4.4121 0.0206 0.0381 0.0000 0.3463 4.4725 0.0206 0.0387 0.0000 0.3463 4.5000 0.0206 0.0389 0.0000 0.3463 Bioretention Hydraulic Table Stage(feet)Area(ac.)Volume(ac-ft.)Discharge(cfs)To Amended(cfs)Infilt(cfs) 4.5000 0.0206 0.0389 0.0000 0.2489 0.0000 4.5604 0.0206 0.0401 0.0000 0.2489 0.0000 4.6209 0.0206 0.0414 0.0000 0.2689 0.0000 4.6813 0.0206 0.0426 0.0000 0.2790 0.0000 4.7418 0.0206 0.0439 0.0000 0.2890 0.0000 229 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:25 PM Page 8 4.8022 0.0206 0.0451 0.0000 0.2990 0.0000 4.8626 0.0206 0.0464 0.0000 0.3091 0.0000 4.9231 0.0206 0.0476 0.0000 0.3191 0.0000 4.9835 0.0206 0.0488 0.0000 0.3291 0.0000 5.0440 0.0206 0.0501 0.0977 0.3391 0.0000 5.1044 0.0206 0.0513 0.3555 0.3463 0.0000 5.1648 0.0206 0.0526 0.6924 0.3463 0.0000 5.2253 0.0206 0.0538 1.0650 0.3463 0.0000 5.2857 0.0206 0.0551 1.4294 0.3463 0.0000 5.3462 0.0206 0.0563 1.7445 0.3463 0.0000 5.4066 0.0206 0.0575 1.9818 0.3463 0.0000 5.4670 0.0206 0.0588 2.1391 0.3463 0.0000 5.5000 0.0206 0.0595 2.2875 0.3463 0.0000 230 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:25 PM Page 9 Surface retention 1 Element Flows To: Outlet 1 Outlet 2 Bioretention 1 231 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:57:25 PM Page 10 Analysis Results POC 1 + Predeveloped x Mitigated Predeveloped Landuse Totals for POC #1 Total Pervious Area: 0.791 Total Impervious Area: 0 Mitigated Landuse Totals for POC #1 Total Pervious Area: 0.028 Total Impervious Area: 0.763 Flow Frequency Method: Log Pearson Type III 17B Flow Frequency Return Periods for Predeveloped. POC #1 Return Period Flow(cfs) 2 year 0.000671 5 year 0.001016 10 year 0.001296 25 year 0.001718 50 year 0.002085 100 year 0.002502 Flow Frequency Return Periods for Mitigated. POC #1 Return Period Flow(cfs) 2 year 0 5 year 0 10 year 0 25 year 0 50 year 0 100 year 0 Annual Peaks 232 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:59:31 PM Page 11 Annual Peaks for Predeveloped and Mitigated. POC #1 Year Predeveloped Mitigated 1949 0.001 0.000 1950 0.001 0.000 1951 0.001 0.000 1952 0.001 0.000 1953 0.001 0.000 1954 0.001 0.000 1955 0.001 0.000 1956 0.001 0.000 1957 0.001 0.000 1958 0.001 0.000 1959 0.001 0.000 1960 0.001 0.000 1961 0.001 0.000 1962 0.001 0.000 1963 0.001 0.000 1964 0.001 0.000 1965 0.001 0.000 1966 0.001 0.000 1967 0.001 0.000 1968 0.001 0.000 1969 0.001 0.000 1970 0.001 0.000 1971 0.001 0.000 1972 0.003 0.000 1973 0.001 0.000 1974 0.001 0.000 1975 0.001 0.000 1976 0.001 0.000 1977 0.000 0.000 1978 0.001 0.000 1979 0.001 0.000 1980 0.001 0.000 1981 0.001 0.000 1982 0.001 0.000 1983 0.001 0.000 1984 0.001 0.000 1985 0.001 0.000 1986 0.001 0.000 1987 0.001 0.000 1988 0.001 0.000 1989 0.001 0.000 1990 0.001 0.000 1991 0.001 0.000 1992 0.001 0.000 1993 0.000 0.000 1994 0.001 0.000 1995 0.001 0.000 1996 0.004 0.000 1997 0.001 0.000 1998 0.001 0.000 1999 0.001 0.063 2000 0.001 0.000 2001 0.001 0.000 2002 0.001 0.000 2003 0.001 0.000 2004 0.001 0.074 233 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:59:31 PM Page 12 2005 0.001 0.000 2006 0.001 0.000 2007 0.007 0.000 2008 0.001 0.000 2009 0.001 0.000 Ranked Annual Peaks Ranked Annual Peaks for Predeveloped and Mitigated. POC #1 Rank Predeveloped Mitigated 1 0.0066 0.0740 2 0.0044 0.0633 3 0.0033 0.0000 4 0.0012 0.0000 5 0.0012 0.0000 6 0.0010 0.0000 7 0.0010 0.0000 8 0.0006 0.0000 9 0.0006 0.0000 10 0.0006 0.0000 11 0.0006 0.0000 12 0.0006 0.0000 13 0.0006 0.0000 14 0.0006 0.0000 15 0.0006 0.0000 16 0.0006 0.0000 17 0.0006 0.0000 18 0.0006 0.0000 19 0.0006 0.0000 20 0.0006 0.0000 21 0.0006 0.0000 22 0.0006 0.0000 23 0.0006 0.0000 24 0.0006 0.0000 25 0.0006 0.0000 26 0.0006 0.0000 27 0.0006 0.0000 28 0.0006 0.0000 29 0.0006 0.0000 30 0.0006 0.0000 31 0.0006 0.0000 32 0.0006 0.0000 33 0.0006 0.0000 34 0.0006 0.0000 35 0.0006 0.0000 36 0.0006 0.0000 37 0.0006 0.0000 38 0.0006 0.0000 39 0.0006 0.0000 40 0.0006 0.0000 41 0.0006 0.0000 42 0.0006 0.0000 43 0.0006 0.0000 44 0.0006 0.0000 45 0.0006 0.0000 46 0.0006 0.0000 47 0.0006 0.0000 48 0.0006 0.0000 49 0.0006 0.0000 234 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:59:31 PM Page 13 50 0.0006 0.0000 51 0.0006 0.0000 52 0.0006 0.0000 53 0.0006 0.0000 54 0.0006 0.0000 55 0.0006 0.0000 56 0.0006 0.0000 57 0.0006 0.0000 58 0.0006 0.0000 59 0.0005 0.0000 60 0.0005 0.0000 61 0.0005 0.0000 235 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:59:32 PM Page 14 LID Duration Flows The Facility PASSED Flow(cfs) Predev Mit Percentage Pass/Fail 0.0001 22351 10 0 Pass 0.0001 21359 10 0 Pass 0.0001 20552 10 0 Pass 0.0001 19868 10 0 Pass 0.0001 19079 10 0 Pass 0.0001 18591 10 0 Pass 0.0001 17939 10 0 Pass 0.0001 17325 10 0 Pass 0.0001 16797 10 0 Pass 0.0001 16281 10 0 Pass 0.0001 15781 10 0 Pass 0.0001 15466 10 0 Pass 0.0001 15058 10 0 Pass 0.0001 14617 10 0 Pass 0.0001 14185 10 0 Pass 0.0001 13768 10 0 Pass 0.0001 13400 10 0 Pass 0.0001 13019 10 0 Pass 0.0001 12799 10 0 Pass 0.0001 12527 10 0 Pass 0.0001 12215 10 0 Pass 0.0001 11952 10 0 Pass 0.0001 11627 10 0 Pass 0.0001 11355 10 0 Pass 0.0001 11064 10 0 Pass 0.0001 10891 10 0 Pass 0.0001 10598 10 0 Pass 0.0001 10271 10 0 Pass 0.0001 10051 10 0 Pass 0.0001 9865 10 0 Pass 0.0001 9681 10 0 Pass 0.0001 9548 10 0 Pass 0.0001 9355 10 0 Pass 0.0001 9165 10 0 Pass 0.0002 8975 10 0 Pass 0.0002 8765 10 0 Pass 0.0002 8585 10 0 Pass 0.0002 8425 10 0 Pass 0.0002 8331 10 0 Pass 0.0002 8158 10 0 Pass 0.0002 8023 10 0 Pass 0.0002 7888 10 0 Pass 0.0002 7762 10 0 Pass 0.0002 7612 10 0 Pass 0.0002 7512 10 0 Pass 0.0002 7375 10 0 Pass 0.0002 7259 10 0 Pass 0.0002 7112 10 0 Pass 0.0002 6934 10 0 Pass 0.0002 6842 10 0 Pass 0.0002 6705 10 0 Pass 0.0002 6628 10 0 Pass 0.0002 6511 10 0 Pass 236 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 4:59:32 PM Page 15 0.0002 6419 10 0 Pass 0.0002 6310 10 0 Pass 0.0002 6196 10 0 Pass 0.0002 6098 10 0 Pass 0.0002 6027 10 0 Pass 0.0002 5908 10 0 Pass 0.0002 5784 10 0 Pass 0.0002 5653 10 0 Pass 0.0002 5542 10 0 Pass 0.0002 5443 10 0 Pass 0.0002 5343 10 0 Pass 0.0002 5260 10 0 Pass 0.0002 5176 10 0 Pass 0.0002 5093 10 0 Pass 0.0002 5024 10 0 Pass 0.0002 4949 10 0 Pass 0.0003 4872 10 0 Pass 0.0003 4827 10 0 Pass 0.0003 4742 10 0 Pass 0.0003 4671 10 0 Pass 0.0003 4573 10 0 Pass 0.0003 4487 10 0 Pass 0.0003 4391 10 0 Pass 0.0003 4308 10 0 Pass 0.0003 4237 10 0 Pass 0.0003 4152 10 0 Pass 0.0003 4081 10 0 Pass 0.0003 4021 10 0 Pass 0.0003 3959 10 0 Pass 0.0003 3897 10 0 Pass 0.0003 3852 10 0 Pass 0.0003 3784 10 0 Pass 0.0003 3726 10 0 Pass 0.0003 3677 10 0 Pass 0.0003 3621 10 0 Pass 0.0003 3572 10 0 Pass 0.0003 3514 10 0 Pass 0.0003 3480 10 0 Pass 0.0003 3422 10 0 Pass 0.0003 3371 10 0 Pass 0.0003 3320 10 0 Pass 0.0003 3266 10 0 Pass 0.0003 3215 9 0 Pass 0.0003 3178 9 0 Pass 0.0003 3127 9 0 Pass 0.0003 3086 9 0 Pass 0.0003 3046 9 0 Pass 237 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:00:05 PM Page 16 Duration Flows Flow(cfs) Predev Mit Percentage Pass/Fail 0.0001 22351 10 0 Pass 0.0001 17158 10 0 Pass 0.0001 14040 10 0 Pass 0.0001 11721 10 0 Pass 0.0001 9920 10 0 Pass 0.0002 8585 10 0 Pass 0.0002 7612 10 0 Pass 0.0002 6663 10 0 Pass 0.0002 5953 10 0 Pass 0.0002 5176 10 0 Pass 0.0003 4671 10 0 Pass 0.0003 4055 10 0 Pass 0.0003 3664 10 0 Pass 0.0003 3283 10 0 Pass 0.0003 2952 9 0 Pass 0.0004 2571 9 0 Pass 0.0004 2257 9 0 Pass 0.0004 1958 9 0 Pass 0.0004 1691 9 0 Pass 0.0004 1461 9 0 Pass 0.0005 1291 9 0 Pass 0.0005 1122 9 0 Pass 0.0005 912 9 0 Pass 0.0005 729 9 1 Pass 0.0005 559 9 1 Pass 0.0006 435 9 2 Pass 0.0006 323 9 2 Pass 0.0006 213 9 4 Pass 0.0006 71 9 12 Pass 0.0006 26 9 34 Pass 0.0007 26 9 34 Pass 0.0007 26 9 34 Pass 0.0007 25 9 36 Pass 0.0007 25 9 36 Pass 0.0008 24 9 37 Pass 0.0008 23 9 39 Pass 0.0008 23 9 39 Pass 0.0008 23 9 39 Pass 0.0008 22 9 40 Pass 0.0009 22 9 40 Pass 0.0009 21 9 42 Pass 0.0009 21 9 42 Pass 0.0009 21 9 42 Pass 0.0009 21 9 42 Pass 0.0010 19 9 47 Pass 0.0010 19 9 47 Pass 0.0010 18 9 50 Pass 0.0010 18 9 50 Pass 0.0010 16 9 56 Pass 0.0011 16 9 56 Pass 0.0011 16 9 56 Pass 0.0011 16 9 56 Pass 0.0011 15 9 60 Pass 0.0011 15 9 60 Pass 238 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:00:05 PM Page 17 0.0012 15 9 60 Pass 0.0012 14 9 64 Pass 0.0012 13 9 69 Pass 0.0012 13 9 69 Pass 0.0012 13 9 69 Pass 0.0013 13 9 69 Pass 0.0013 13 9 69 Pass 0.0013 12 9 75 Pass 0.0013 12 9 75 Pass 0.0013 11 9 81 Pass 0.0014 11 9 81 Pass 0.0014 11 9 81 Pass 0.0014 11 9 81 Pass 0.0014 10 9 90 Pass 0.0014 10 9 90 Pass 0.0015 9 9 100 Pass 0.0015 9 9 100 Pass 0.0015 9 9 100 Pass 0.0015 9 9 100 Pass 0.0016 8 9 112 Fail 0.0016 8 9 112 Fail 0.0016 8 9 112 Fail 0.0016 8 9 112 Fail 0.0016 8 9 112 Fail 0.0017 8 9 112 Fail 0.0017 8 9 112 Fail 0.0017 8 9 112 Fail 0.0017 8 9 112 Fail 0.0017 8 9 112 Fail 0.0018 8 9 112 Fail 0.0018 8 9 112 Fail 0.0018 8 9 112 Fail 0.0018 8 9 112 Fail 0.0018 8 9 112 Fail 0.0019 8 9 112 Fail 0.0019 8 9 112 Fail 0.0019 8 9 112 Fail 0.0019 8 9 112 Fail 0.0019 8 9 112 Fail 0.0020 8 9 112 Fail 0.0020 8 9 112 Fail 0.0020 8 9 112 Fail 0.0020 8 9 112 Fail 0.0020 8 9 112 Fail 0.0021 8 9 112 Fail 0.0021 8 9 112 Fail The development has an increase in flow durations from 1/2 Predeveloped 2 year flow to the 2 year flow or more than a 10% increase from the 2 year to the 50 year flow. 239 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:00:05 PM Page 18 Water Quality Water Quality BMP Flow and Volume for POC #1 On-line facility volume: 0 acre-feet On-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. Off-line facility target flow: 0 cfs. Adjusted for 15 min: 0 cfs. 240 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:00:05 PM Page 19 LID Report 241 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:00:46 PM Page 20 Model Default Modifications Total of 0 changes have been made. PERLND Changes No PERLND changes have been made. IMPLND Changes No IMPLND changes have been made. 242 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:00:46 PM Page 21 Appendix Predeveloped Schematic 243 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:01:11 PM Page 22 Mitigated Schematic 244 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:01:38 PM Page 23 Predeveloped UCI File 245 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:01:38 PM Page 24 Mitigated UCI File 246 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:01:38 PM Page 25 Predeveloped HSPF Message File 247 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:01:38 PM Page 26 Mitigated HSPF Message File 248 of 347 DRAFTGarden Ave Realignment_6.5bgs_282iph 3/16/2023 5:01:38 PM Page 27 Disclaimer Legal Notice This program and accompanying documentation are provided 'as-is' without warranty of any kind. The entire risk regarding the performance and results of this program is assumed by End User. Clear Creek Solutions Inc. and the governmental licensee or sublicensees disclaim all warranties, either expressed or implied, including but not limited to implied warranties of program and accompanying documentation. In no event shall Clear Creek Solutions Inc. be liable for any damages whatsoever (including without limitation to damages for loss of business profits, loss of business information, business interruption, and the like) arising out of the use of, or inability to use this program even if Clear Creek Solutions Inc. or their authorized representatives have been advised of the possibility of such damages. Software Copyright © by : Clear Creek Solutions, Inc. 2005-2023; All Rights Reserved. Clear Creek Solutions, Inc. 6200 Capitol Blvd. Ste F Olympia, WA. 98501 Toll Free 1(866)943-0304 Local (360)943-0304 www.clearcreeksolutions.com 249 of 347 Appendix D Geotechnical Data 250 of 347 251 of 347 CLAYEY GRAVELS, POORLY GRADED GRAVEL-SAND-CLAY MIXTURES SILTS AND CLAYSCOARSE GRAINED SOILSMore than Half > #200 sieveLIQUID LIMIT LESS THAN 50 LIQUID LIMIT GREATER THAN 50 CLEAN GRAVELS WITH LITTLE OR NO FINES GRAVELS WITH OVER 15% FINES CLEAN SANDS WITH LITTLE OR NO FINES MORE THAN HALF COARSE FRACTION IS SMALLER THAN NO. 4 SIEVE MORE THAN HALF COARSE FRACTION IS LARGER THAN NO. 4 SIEVE INORGANIC SILTS, MICACEOUS OR DIATOMACIOUS FINE SANDY OR SILTY SOILS, ELASTIC SILTS ORGANIC CLAYS AND ORGANIC SILTY CLAYS OF LOW PLASTICITY OH INORGANIC SILTS AND VERY FINE SANDS, ROCK FLOUR, SILTY OR CLAYEY FINE SANDS, OR CLAYEY SILTS WITH SLIGHT PLASTICITY CH SILTY GRAVELS, POORLY GRADED GRAVEL-SAND-SILT MIXTURES SANDS SILTS AND CLAYS Figure A-1 INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS E3RA R-Value Sieve Analysis Swell Test Cyclic Triaxial Unconsolidated Undrained Triaxial Torvane Shear Unconfined Compression (Shear Strength, ksf) Wash Analysis (with % Passing No. 200 Sieve) Water Level at Time of Drilling Water Level after Drilling(with date measured) RV SA SW TC TX TV UC (1.2) WA (20) Modified California Split Spoon Pushed Shelby Tube Auger Cuttings Grab Sample Sample Attempt with No Recovery Chemical Analysis Consolidation Compaction Direct Shear Permeability Pocket Penetrometer CA CN CP DS PM PP PtHIGHLY ORGANIC SOILS TYPICAL NAMES GRAVELS ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY, ORGANIC SILTS WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES MAJOR DIVISIONS PEAT AND OTHER HIGHLY ORGANIC SOILS WELL GRADED SANDS, GRAVELLY SANDS POORLY GRADED SANDS, GRAVELLY SANDS SILTY SANDS, POOORLY GRADED SAND-SILT MIXTURES CLAYEY SANDS, POORLY GRADED SAND-CLAY MIXTURES POORLY GRADED GRAVELS, GRAVEL-SAND MIXTURES SOIL CLASSIFICATION CHART AND KEY TO TEST DATA GW GP GM GC SW SP SM SC ML FINE GRAINED SOILSMore than Half < #200 sieveLGD A NNNN02 GINT US LAB.GPJ 11/4/05INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS CL OL MH SANDS WITH OVER 15% FINES Migizi Group, Inc. 252 of 347 GB S-1 GB S-2 GB S-3 GB S-4 SM SM SM SP- SM GP GP 0.4 1.0 2.0 4.5 5.0 8.0 8.5 Sod and Topsoil (SM) Gray/brown silty sand with gravel (dense, damp) (Fill) (SM) Brown mottled fine silty sand (medium dense, moist) (SM) Red/brown fine silty sand (loose, moist) (SP-SM) Brown fine sand with silt (loose, moist) (GP) Dark gray gravel with fine to coarse sand (medium dense, moist) (GP) Red/brown gravel with fine sand and some silt (dense, wet) Severe caving observed from 4.5 to 8 feet Groundwater seepage observed at 8.5 feet The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. Bottom of test pit at 8.5 feet. NOTES LOGGED BY ZLL EXCAVATION METHOD Rubber-tracked Excavator EXCAVATION CONTRACTOR DSE GROUND WATER LEVELS: CHECKED BY JEB DATE STARTED 5/18/16 COMPLETED 5/18/16 AT TIME OF EXCAVATION 8.50 ft AT END OF EXCAVATION --- AFTER EXCAVATION --- TEST PIT SIZEGROUND ELEVATION SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 PAGE 1 OF 1 Figure A-2 TEST PIT NUMBER TP-1 CLIENT Azure Green Consultants PROJECT NUMBER P648-T16 PROJECT NAME JK Monarch Residential Development PROJECT LOCATION 102nd & 104th Ave SE, Auburn, WA COPY OF GENERAL BH / TP LOGS - FIGURE.GDT - 5/19/16 15:26 - C:\USERS\JESSICA\DESKTOP\TEST PITS AND BORINGS - GINT\P648-T16\P648-T16 TEST PITS.GPJMigizi Group, Inc. PO Box 44840 Tacoma, WA 98448 Telephone: 253-537-9400 Fax: 253-537-9401 U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION 253 of 347 GB S-1 GB S-2 SM SM SP- SM SP GP GP 0.7 1.5 4.0 5.0 8.5 9.5 10.0 Sod and Topsoil (SM) Gray/brown silty sand with gravel (dense, damp) (Fill) (SM) Brown fine silty sand (loose, moist) (SP-SM) Brown fine sand with silt (loose, moist) (SP) Gray fine to medium sand (loose, moist) (GP) Dark gray gravel with fine to coarse sand (medium dense, moist) (GP) Red/brown gravel with fine sand and some silt (dense, wet) Severe caving observed from 5 to 9.5 feet Groundwater seepage observed at 10 feet The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. Bottom of test pit at 10.0 feet. NOTES LOGGED BY ZLL EXCAVATION METHOD Rubber-tracked Excavator EXCAVATION CONTRACTOR DSE GROUND WATER LEVELS: CHECKED BY JEB DATE STARTED 5/18/16 COMPLETED 5/18/16 AT TIME OF EXCAVATION 10.00 ft AT END OF EXCAVATION --- AFTER EXCAVATION --- TEST PIT SIZEGROUND ELEVATION SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 10.0 PAGE 1 OF 1 Figure A-3 TEST PIT NUMBER TP-2 CLIENT Azure Green Consultants PROJECT NUMBER P648-T16 PROJECT NAME JK Monarch Residential Development PROJECT LOCATION 102nd & 104th Ave SE, Auburn, WA COPY OF GENERAL BH / TP LOGS - FIGURE.GDT - 5/19/16 15:26 - C:\USERS\JESSICA\DESKTOP\TEST PITS AND BORINGS - GINT\P648-T16\P648-T16 TEST PITS.GPJMigizi Group, Inc. PO Box 44840 Tacoma, WA 98448 Telephone: 253-537-9400 Fax: 253-537-9401 U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION 254 of 347 GB S-1 GB S-2 SM SM SP- SM GP GP 0.7 1.5 5.0 6.0 10.0 11.5 Sod and Topsoil (SM) Gray/brown silty sand with gravel and some asphalt debris (dense, damp) (Fill) (SM) Dark brown fine silty sand (loose, moist) (SP-SM) Brown fine sand with silt (loose, moist) (GP) Dark gray gravel with fine to coarse sand and scattered cobbles (medium dense, moist) (GP) Red/brown gravel with fine sand and some silt (dense, wet) Severe caving observed from 5 to 10 feet Groundwater seepage observed at 11 feet The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. Bottom of test pit at 11.5 feet. NOTES LOGGED BY ZLL EXCAVATION METHOD Rubber-tracked Excavator EXCAVATION CONTRACTOR DSE GROUND WATER LEVELS: CHECKED BY JEB DATE STARTED 5/18/16 COMPLETED 5/18/16 AT TIME OF EXCAVATION 11.00 ft AT END OF EXCAVATION --- AFTER EXCAVATION --- TEST PIT SIZEGROUND ELEVATION SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 10.0 PAGE 1 OF 1 Figure A-4 TEST PIT NUMBER TP-3 CLIENT Azure Green Consultants PROJECT NUMBER P648-T16 PROJECT NAME JK Monarch Residential Development PROJECT LOCATION 102nd & 104th Ave SE, Auburn, WA COPY OF GENERAL BH / TP LOGS - FIGURE.GDT - 5/19/16 15:26 - C:\USERS\JESSICA\DESKTOP\TEST PITS AND BORINGS - GINT\P648-T16\P648-T16 TEST PITS.GPJMigizi Group, Inc. PO Box 44840 Tacoma, WA 98448 Telephone: 253-537-9400 Fax: 253-537-9401 U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION 255 of 347 GB S-1 GB S-2 SM SM ML ML SP- SM GP 0.9 2.0 3.5 4.5 6.5 7.5 11.0 Sod and Topsoil (SM) Gray/brown silty sand with gravel and chunks of concrete (dense, damp) (Fill) (SM) Brown fine silty sand with lenses of blue/gray silty sand (loose, moist) (ML) Blue/gray silt (soft, moist) (ML) Gray/brown oxidized sandy silt (soft, moist) (SP-SM) Brown fine sand with silt (loose, moist) (GP) Dark gray gravel with fine to coarse sand and scattered cobbles (medium dense, moist) Severe caving observed from 7.5 to 11 feet Groundwater seepage observed at 11 feet The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. Bottom of test pit at 11.0 feet. NOTES LOGGED BY ZLL EXCAVATION METHOD Rubber-tracked Excavator EXCAVATION CONTRACTOR DSE GROUND WATER LEVELS: CHECKED BY JEB DATE STARTED 5/18/16 COMPLETED 5/18/16 AT TIME OF EXCAVATION 11.00 ft AT END OF EXCAVATION --- AFTER EXCAVATION --- TEST PIT SIZEGROUND ELEVATION SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 10.0 PAGE 1 OF 1 Figure A-5 TEST PIT NUMBER TP-4 CLIENT Azure Green Consultants PROJECT NUMBER P648-T16 PROJECT NAME JK Monarch Residential Development PROJECT LOCATION 102nd & 104th Ave SE, Auburn, WA COPY OF GENERAL BH / TP LOGS - FIGURE.GDT - 5/19/16 15:26 - C:\USERS\JESSICA\DESKTOP\TEST PITS AND BORINGS - GINT\P648-T16\P648-T16 TEST PITS.GPJMigizi Group, Inc. PO Box 44840 Tacoma, WA 98448 Telephone: 253-537-9400 Fax: 253-537-9401 U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION 256 of 347 GB S-1 GB S-2 SM SP- SM GP 0.8 4.5 6.5 10.5 Sod and Topsoil (SM) Brown fine silty sand (loose, moist) (SP-SM) Brown fine sand with silt (loose, moist) (GP) Dark gray gravel with fine to coarse sand and scattered cobbles (medium dense, moist) Severe caving observed from 6.5 to 10 feet Groundwater seepage observed at 10 feet The depths on the test pit logs are based on an average of measurements across the test pit and should be considered accurate to 0.5 foot. Bottom of test pit at 10.5 feet. NOTES LOGGED BY ZLL EXCAVATION METHOD Rubber-tracked Excavator EXCAVATION CONTRACTOR DSE GROUND WATER LEVELS: CHECKED BY JEB DATE STARTED 5/18/16 COMPLETED 5/18/16 AT TIME OF EXCAVATION 10.00 ft AT END OF EXCAVATION --- AFTER EXCAVATION --- TEST PIT SIZEGROUND ELEVATION SAMPLE TYPENUMBERDEPTH(ft)0.0 2.5 5.0 7.5 10.0 PAGE 1 OF 1 Figure A-6 TEST PIT NUMBER TP-5 CLIENT Azure Green Consultants PROJECT NUMBER P648-T16 PROJECT NAME JK Monarch Residential Development PROJECT LOCATION 102nd & 104th Ave SE, Auburn, WA COPY OF GENERAL BH / TP LOGS - FIGURE.GDT - 5/19/16 15:26 - C:\USERS\JESSICA\DESKTOP\TEST PITS AND BORINGS - GINT\P648-T16\P648-T16 TEST PITS.GPJMigizi Group, Inc. PO Box 44840 Tacoma, WA 98448 Telephone: 253-537-9400 Fax: 253-537-9401 U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION 257 of 347 Job Name:JK Monarch Residential Development Job Number:P648-T16 Tested By:ZLL Date:5/18/16 Boring #:TP-1 Sample #:S-4 Depth:6.5 feet Moisture Content (%)2.8% Sieve Size Percent Passing (%)Size Fraction Percent By Weight 3.0 in. (75.0)100.0 Coarse Gravel 30.4 1.5 in. (37.5)100.0 Fine Gravel 27.6 3/4 in. (19.0)69.6 3/8 in. (9.5-mm)53.5 Coarse Sand 9.8 No. 4 (4.75-mm)42.1 Medium Sand 28.6 No. 10 (2.00-mm)32.3 Fine Sand 3.1 No. 20 (.850-mm)19.0 No. 40 (.425-mm)3.7 Fines 0.6 No. 60 (.250-mm)1.2 Total 100.0 No. 100 (.150-mm)0.7 No. 200 (.075-mm)0.6 LL PI D10 0.57 D30 1.73 D60 12.57 Cc 0.42 Cu 22.24 Group Name Dark-gray poorly graded gravel with sand Symbol (GP) (med. dense, moist) Figure B-1 Soil Classification Data Sheet Particle Size Analysis Summary Data ASTM Classification 258 of 347 Sample Distribution Job Name:JK Monarch Residential Development Sample #:S-4 Job Number:P648-T16 Date:5/18/16 Figure:B-2 Tested By:ZLL Depth:6.5 feet Exploration #:TP-1 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.11101001000Percent PassingParticle Size (mm) Sample Distribution Sample Distribution U.S. Standard Sieve Sizes 3"1.5"3/4"3/8"4 10 4020 60 100 200 259 of 347 Job Name:JK Monarch Residential Development Job Number:P648-T16 Tested By:ZLL Date:5/18/16 Boring #:TP-2 Sample #:S-2 Depth:4.5 feet Moisture Content (%)12.7% Sieve Size Percent Passing (%)Size Fraction Percent By Weight 3.0 in. (75.0)100.0 Coarse Gravel 1.5 in. (37.5)100.0 Fine Gravel 0.1 3/4 in. (19.0)100.0 3/8 in. (9.5-mm)100.0 Coarse Sand 0.3 No. 4 (4.75-mm)99.9 Medium Sand 1.1 No. 10 (2.00-mm)99.7 Fine Sand 86.2 No. 20 (.850-mm)99.2 No. 40 (.425-mm)98.6 Fines 12.3 No. 60 (.250-mm)82.4 Total 100.0 No. 100 (.150-mm)36.0 No. 200 (.075-mm)12.3 LL PI D10 D30 0.13 D60 0.20 Cc Cu Group Name Brown silty sand Symbol (SM) (loose, moist) Figure B-3 Soil Classification Data Sheet Particle Size Analysis Summary Data ASTM Classification 260 of 347 Sample Distribution Job Name:JK Monarch Residential Development Sample #:S-2 Job Number:P648-T16 Date:5/18/16 Figure:B-4 Tested By:ZLL Depth:4.5 feet Exploration #:TP-2 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.11101001000Percent PassingParticle Size (mm) Sample Distribution Sample Distribution U.S. Standard Sieve Sizes 3"1.5"3/4"3/8"4 10 4020 60 100 200 261 of 347 Job Name:JK Monarch Residential Development Job Number:P648-T16 Tested By:ZLL Date:5/18/16 Boring #:TP-3 Sample #:S-2 Depth:3.5 feet Moisture Content (%)27.4% Sieve Size Percent Passing (%)Size Fraction Percent By Weight 3.0 in. (75.0)100.0 Coarse Gravel 1.5 in. (37.5)100.0 Fine Gravel 0.7 3/4 in. (19.0)100.0 3/8 in. (9.5-mm)99.7 Coarse Sand 1.1 No. 4 (4.75-mm)99.3 Medium Sand 5.0 No. 10 (2.00-mm)98.2 Fine Sand 44.8 No. 20 (.850-mm)96.0 No. 40 (.425-mm)93.1 Fines 48.4 No. 60 (.250-mm)87.9 Total 100.0 No. 100 (.150-mm)72.8 No. 200 (.075-mm)48.4 LL PI D10 D30 D60 0.10 Cc Cu Group Name Brown silty sand Symbol (SM) (loose, moist) Figure B-5 Soil Classification Data Sheet Particle Size Analysis Summary Data ASTM Classification 262 of 347 Sample Distribution Job Name:JK Monarch Residential Development Sample #:S-2 Job Number:P648-T16 Date:5/18/16 Figure:B-6 Tested By:ZLL Depth:3.5 feet Exploration #:TP-3 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.11101001000Percent PassingParticle Size (mm) Sample Distribution Sample Distribution U.S. Standard Sieve Sizes 3"1.5"3/4"3/8"4 10 4020 60 100 200 263 of 347 Job Name:JK Monarch Residential Development Job Number:P648-T16 Tested By:ZLL Date:5/18/16 Boring #:TP-5 Sample #:S-1 Depth:1.5 feet Moisture Content (%)19.0% Sieve Size Percent Passing (%)Size Fraction Percent By Weight 3.0 in. (75.0)100.0 Coarse Gravel 1.5 in. (37.5)100.0 Fine Gravel 3/4 in. (19.0)100.0 3/8 in. (9.5-mm)100.0 Coarse Sand 1.3 No. 4 (4.75-mm)100.0 Medium Sand 4.9 No. 10 (2.00-mm)98.7 Fine Sand 55.9 No. 20 (.850-mm)96.4 No. 40 (.425-mm)93.8 Fines 37.8 No. 60 (.250-mm)87.7 Total 100.0 No. 100 (.150-mm)64.4 No. 200 (.075-mm)37.8 LL PI D10 D30 D60 0.13 Cc Cu Group Name Brown silty sand Symbol (SM) (loose, moist) Figure B-7 Soil Classification Data Sheet Particle Size Analysis Summary Data ASTM Classification 264 of 347 Sample Distribution Job Name:JK Monarch Residential Development Sample #:S-1 Job Number:P648-T16 Date:5/18/16 Figure:B-8 Tested By:ZLL Depth:1.5 feet Exploration #:TP-5 0 10 20 30 40 50 60 70 80 90 100 0.0010.010.11101001000Percent PassingParticle Size (mm) Sample Distribution Sample Distribution U.S. Standard Sieve Sizes 3"1.5"3/4"3/8"4 10 4020 60 100 200 265 of 347 Soil Map—King County Area, Washington (Auburn - Soils) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 9/27/2021 Page 1 of 3524047052405505240630524071052407905240870524095052410305241110524047052405505240630524071052407905240870524095052410305241110559820559900559980560060560140560220560300 559820 559900 559980 560060 560140 560220 560300 47° 19' 15'' N 122° 12' 31'' W47° 19' 15'' N122° 12' 6'' W47° 18' 53'' N 122° 12' 31'' W47° 18' 53'' N 122° 12' 6'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 150 300 600 900 Feet 0 45 90 180 270 Meters Map Scale: 1:3,310 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. 266 of 347 MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: King County Area, Washington Survey Area Data: Version 16, Jun 4, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 25, 2020—Jul 27, 2020 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Soil Map—King County Area, Washington (Auburn - Soils) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 9/27/2021 Page 2 of 3 267 of 347 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI AgC Alderwood gravelly sandy loam, 8 to 15 percent slopes 0.7 1.3% AkF Alderwood and Kitsap soils, very steep 2.7 5.4% Ma Mixed alluvial land 3.8 7.6% Os Oridia silt loam 25.4 51.1% Ur Urban land 14.5 29.1% W Water 2.7 5.5% Totals for Area of Interest 49.7 100.0% Soil Map—King County Area, Washington Auburn - Soils Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 9/27/2021 Page 3 of 3 268 of 347 Project Name:Garden Ave. Realignment SSP ReportClient:City of AuburnProject Number: 21-3259Developed By:Melissa DiLoretoDate:12.05.2022Checked By:Nichole KruseDate Checked: 12.13.2022 Purpose:Summary:Referenced Geotechnical Data:This spreadsheet calculates the infiltration rate of existing soil conditions based on geotechnical sample data using the Ksat Determination Option 3 method per the Washington State Department of Ecology 2019 Stormwater Management Manual for Western Washington (soil grain size analysis). 1. The “Sample T-1” tab includes a calculated infiltra5on rate based on informa5on from boring T-1 in the development geotechnical report. The data is for the soils that are from a depth of 6.5-ft deep, which is the deeper of the two samples. 2. The “Sample T-2” tab includes a calculated infiltration rate based on the information from boring T-2 in the development geotechnical report. The data is for the soils that are from a depth of 4.5-ft deep. 3. At a depth of 4.5 feet, an infiltration rate of 22 inches per hour was calculated.5. At a depth of 6.5 feet, an infiltration rate of 282 inches per hour was calculated.Geotechnical data referenced in these calculations are extracted from the "JK Monarch Residential Development" report prepared for Azure Green Consultants on May 24, 2016. The locations of the borings are shown in the map below relative to the City's planned improvements.269 of 347 Proposed BMPLocationDevelopmentGeotechnical Boring Locations270 of 347 Tab:Sample T-1Background:Data shown on this tab is copied from the historical boringsCalculations By:Melissa DiLoretoDate:12.05.2022Checked By:Nichole KruseDate Checked: 12.13.2022Variable Value Unit NotesExcerpt from Washington State Department of Ecology 2019 Stormwater Management Manual for Western WashingtonD100.57 mmgrain size for which 10% is more fine(See Table Below for Value)D6012.57 mmgrain size for which 60% is more fine(See Table Below for Value)D9030 mmgrain size for which 90% is more fine(See Graph Below for Value)f fines 0.60% %fraction of soil by weight that passes the #200 sieve(See Table Below for Value)INPUTSlog10(Ksat) -0.70uses the equation provided by EcologyKsat (cm/s) 0.20 cm/s inverse logKsat (in/hr) 282.12 in/hr uses the conversion 1cm/sec=1,417in/hrOUTPUTS30D90 Valuef FinesD90 ValueD10 ValueD60 Value271 of 347 Tab:Sample T-2Background:Data shown on this tab is copied from the historical boringsCalculations By:Melissa DiLoretoDate:12.05.2022Checked By:Nichole KruseDate Checked: 12.13.2022Variable Value Unit NotesExcerpt from Washington State Department of Ecology 2019 Stormwater Management Manual for Western WashingtonD100.012 mmgrain size for which 10% is more fine(See Table Below for Value)D600.2 mmgrain size for which 60% is more fine(See Table Below for Value)D900.3 mmgrain size for which 90% is more fine(See Graph Below fopr Value)f fines 12.30% %fraction of soil by weight that passes the #200 sieve(See Table Below for Value)INPUTSlog10(Ksat) -1.80uses the equation provided by EcologyKsat (cm/s) 0.02 cm/s inverse logKsat (in/hr) 22.26 in/hr uses the conversion 1cm/sec=1,417in/hrOUTPUTSf FinesD60 ValueD10 ValueD90 Value0.3272 of 347 Appendix E Critical Area Maps 273 of 347 274 of 347 SE 320th SE 104thApprox Project Area 275 of 347 Key Riparian Habitat Bounds Approximate Project Boundary N Riparian Habitat Boundaries Near Proposed Project 276 of 347 Appendix F Department of Ecology Bioretention Planter Example 277 of 347 DEPARTMENT OF ECOLOGY State of Washington Please see http://www.ecy.wa.gov/copyright.html for copyright notice including permissions, limitation of liability, and disclaimer. Example of a Bioretention Planter Revised October 2016 NOT TO SCALE DESIGNER INFORMATION: 1. Adapt plan view example to your engineered design. 2. Include beginning and ending stations for each facility. Provide stations and/or dimensions and elevations at every inlet, outlet, check dam, planter corner and sidewalk notch. 3. Longitudinal slope of planter matches road. 4. Sidewalk elevation must be set above inlet and outlet elevations to allow overflow to drain to street before sidewalk. 5. Minimum interior planter width is 3 feet. A minimum of 4 feet interior planter width is required for street trees in planter. 6. Existing utility lines must be sleeved or relocated. Proposed utility lines to be located out of the facility. 7. Area and depth of facility are based upon engineering calculations and right-of-way constraints. 8. May use concrete or pavers.OverflowStreetInflowMetal inletSpecify lengthCurb & gutter 2'-6" 6" 3'-0" min. 6" Sidewalk Channel & grate (see note 2) 4" notch for sidewalk drianage, as necessary PlanterCheck dam (see note 2) 4" thick concrete splash pad at inlet 1'-6" Concrete or pavers 6'-0" typ. AA Plan View Section A-A 2'-6" Finished grade of planter Concrete or pavers (to be specified by designer) Curb and gutter (by others) Existing subgrade Open graded aggregate (when required) 3'-0" min 18" min Bioretention Soil Mix 6" bench for curb construction Planter wall Sidewalk drainage notch to be 1" lower than sidewalk, sloped to facility Top of wall at end of planter 12" max 4" min. exposed wall 278 of 347 Appendix G City of Auburn 90% Plans with Surface Area Delineations 279 of 347 14,278 sf 777 sf 426 sf Proposed Bioretention Area New Pervious Sidewalk Replaced Impervious Area New Impervious Area11,167 sf 4,593 sf1,862 sf 6,866 sf 2,442 sf Disparate Areas Total Areas Area Types Landscaping and Vegetated Area250 sf 99 sf1,356 sf 11,167 sf 22,085 sf 1,203 sf 9,308 sf 5,620 sf 1,352 sf 1,922 sf 1,993 sf SEE DETAIL 1 FOR CONTINUATION DETAIL 1 - CONTINUATION OF IMPROVEMENTS 280 of 347 Appendix H Minimum Requirements Flow Charts 281 of 347 282 of 347 283 of 347 COA Supplemental Manual to the Ecology Stormwater Management Manual for Western Washington Volume I - Minimum Technical Requirements and Site Planning Version 4 8 Figure 2.5.1 A Flow Chart for Determining LID MR #5 Requirements in the City of Auburn 284 of 347 SEPA ENVIRONMENTAL CHECKLIST Date Received: Physical Address: Auburn City Hall Annex, 2nd Floor 1 E Main St Mailing Address: 25 W Main St Auburn, WA 98001 Webpage & Application Submittal: www.auburnwa.gov applications@auburnwa.gov Phone and Email: 253-931-3090 permitcenter@auburnwa.gov Project Name: Parcel Number(s): A. Background [help] 1. Name of proposed project, if applicable: 2. Name of Applicant: Name of Agent (if applicable): 3. Address and phone number of Applicant: Address and phone number of Agent (if applicable): 4. Date Checklist prepared: Date(s) Checklist Revised: 5. Agency requesting checklist: 6. Proposed timing or schedule (including phasing, if applicable). 7. Do you have any plans for future additions, expansion, or further activity related to or connected with this proposal? If yes, explain. 8. List any environmental information you know about that has been prepared, or will be prepared, directly related to this proposal. 9. Do you know whether applications are pending for governmental approvals of other proposals directly affecting the property covered by your proposal? If yes, explain. 10. List any government approvals or permits that will be needed for your proposal, if known. 11. Give brief, complete description of your proposal, including the proposed uses and the size of the project and site. There are several questions later in this checklist that ask you to describe certain aspects of your proposal. You do not need to repeat those answers on this page. 285 of 347 EXHIBIT 9 12.Location of the proposal. Give sufficient information for a person to understand the precise location of your proposed project, including a street address, if any, and section, township, and range, if known. If a proposal would occur over a range of area, provide the range or boundaries of the site(s). Provide a legal description, site plan, vicinity map, and topographic map, if reasonably available. While you should submit any plans required by the agency, you are not required to duplicate maps or detailed plans submitted with any permit applications related to this checklist. B.Environmental Elements [help] 1.Earth [help] a.General description of the site:  flat,  rolling,  hilly,  steep slopes,  mountainous,  other b.What is the steepest slope on the site (approximate percent slope)? c.What general types of soils are found on the site (for example, clay, sand, gravel, peat, muck)? If you know the classification of agricultural soils, specify them and note any agricultural land of long-term commercial significance and whether the proposal results in removing any of these soils. d.Are there surface indications or history of unstable soils in the immediate vicinity? If so, describe. e.Describe the purpose, type, total area, and approximate quantities and total affected area of any filling, excavation, and grading proposed. Indicate source of fill. f.Could erosion occur as a result of clearing, construction, or use? If so, generally describe. g.About what percent of the site will be covered with impervious surfaces after project construction (for example, asphalt or buildings)? h.Proposed measures to reduce or control erosion, or other impacts to the earth, if any: 2.Air [help] a.What types of emissions to the air would result from the proposal during construction, operation, and maintenance when the project is completed? If any, generally describe and give approximate quantities if known. b.Are there any off-site sources of emissions or odor that may affect your proposal? If so, generally describe. c.Proposed measures to reduce or control emissions or other impacts to air, if any: 286 of 347 3. Water [help] a. Surface Water. [help] 1. Is there any surface water body on or in the immediate vicinity of the site (including year-round and seasonal streams, saltwater, lakes, ponds, wetlands)? If yes, describe type and provide names. If appropriate, state what stream or river it flows into. 2. Will the project require any work over, in, or adjacent to (within 200 feet) the described waters? If yes, please describe and attach available plans. 3. Estimate the amount of fill and dredge material that would be placed in or removed from surface water or wetlands and indicate the area of the site that would be affected. Indicate the source of fill material. 4. Will the proposal require surface water withdrawals or diversions? Give general description, purpose, and approximate quantities if known. 5. Does the proposal lie within a 100-year floodplain? If so, note location on the site plan. 6. Does the proposal involve any discharges of waste materials to surface waters? If so, describe the type of waste and anticipated volume of discharge. b. Ground Water. [help] 1. Will groundwater be withdrawn from a well for drinking water or other purposes? If so, give a general description of the well, proposed uses and approximate quantities withdrawn from the well. Will water be discharged to groundwater? Give general description, purpose, and approximate quantities if known. 2. Describe waste material that will be discharged into the ground from septic tanks or other sources, if any (for example: Domestic sewage; industrial, containing the following chemicals. . . ; agricultural; etc.). Describe the general size of the system, the number of such systems, the number of houses to be served (if applicable), or the number of animals or humans the system(s) are expected to serve. c. Water runoff (including stormwater). 1. Describe the source of runoff (including storm water) and method of collection and disposal, if any (include quantities, if known). Where will this water flow? Will this water flow into other waters? If so, describe. 2. Could waste materials enter ground or surface waters? If so, generally describe. 3. Does the proposal alter or otherwise affect drainage patterns in the vicinity of the site? If so, describe. 287 of 347 4.Plants [help] a.Check the types of vegetation found on the site: deciduous tree:  alder,  maple,  aspen,  other evergreen tree:  fir,  cedar,  pine,  other shrubs grass pasture crop or grain orchards, vineyards or other permanent crops wet soil plants:  cattail,  buttercup,  bullrush,  skunk cabbage,  other water plants:  water lily,  eelgrass,  milfoil,  other other types of vegetation b.What kind and amount of vegetation will be removed or altered? c.List threatened and endangered species known to be on or near the site. d.Proposed landscaping, use of native plants, or other measures to preserve or enhance vegetation on the site, if any: e.List all noxious weeds and invasive species known to be on or near the site. 5.Animals [help] a.Check any birds and other animals which have been observed on or near the site or are known to be on or near the site. Birds:  hawk,  heron,  eagle,  songbirds,  geese,  ducks,  crows,  other Mammals:  deer,  bear,  elk,  beaver,  other Fish:  bass,  salmon,  trout,  herring,  shellfish,  other b.List any threatened and endangered species known to be on or near the site. c. Is the site part of a migration route? If so, explain. d.Proposed measures to preserve or enhance wildlife, if any: e.List any invasive animal species known to be on or near the site. 6.Energy and Natural Resources [help] a.What kinds of energy (electric, natural gas, oil, wood stove, solar) will be used to meet the completed project's energy needs? Describe whether it will be used for heating, manufacturing, etc. b.Would your project affect the potential use of solar energy by adjacent properties? If so, generally describe. c.What kinds of energy conservation features are included in the plans of this proposal? List other proposed measures to reduce or control energy impacts, if any: 288 of 347 7. Environmental Health [help] a. Are there any environmental health hazards, including exposure to toxic chemicals, risk of fire and explosion, spill, or hazardous waste, that could occur as a result of this proposal? If so, describe. 1. Describe any known or possible contamination at the site from present or past uses. 2. Describe existing hazardous chemicals/conditions that might affect project development and design. This includes underground hazardous liquid and gas transmission pipelines located within the project area and in the vicinity. 3. Describe any toxic or hazardous chemicals that might be stored, used, or produced during the project's development or construction, or at any time during the operating life of the project. 4. Describe special emergency services that might be required. 5. Proposed measures to reduce or control environmental health hazards, if any: b. Noise. 1. What types of noise exist in the area which may affect your project (for example: traffic, equipment, operation, other)? 2. What types and levels of noise would be created by or associated with the project on a short-term or a long-term basis (for example: traffic, construction, operation, other)? Indicate what hours noise would come from the site. 3. Proposed measures to reduce or control noise impacts, if any: 8. Land and Shoreline Use [help] a. What is the current use of the site and adjacent properties? Will the proposal affect current land uses on nearby or adjacent properties? If so, describe. b. Has the project site been used as working farmlands or working forest lands? If so, describe. How much agricultural or forest land of long-term commercial significance will be converted to other uses as a result of the proposal, if any? If resource lands have not been designated, how many acres in farmland or forest land tax status will be converted to nonfarm or nonforest use? 1. Will the proposal affect or be affected by surrounding working farm or forest land normal business operations, such as oversize equipment access, the application of pesticides, tilling, and harvesting? If so, how: 289 of 347 290 of 347 c.Describe any structures on the site. d.Will any structures be demolished? If so, what? e.What is the current zoning classification of the site? f.What is the current Comprehensive Plan designation of the site? g.If applicable, what is the current Shoreline Master Program designation of the site? h.Has any part of the site been classified as a critical area? If so, specify. i.Approximately how many people would reside or work in the completed project? j.Approximately how many people would the completed project displace? k.Proposed measures to avoid or reduce displacement impacts, if any: L.Proposed measures to ensure the proposal is compatible with existing and projected land uses and plans, if any: m.Proposed measures to reduce or control impacts to agricultural and forest lands of long-term commercial significance, if any: 9.Housing [help] a.Approximately how many units would be provided, if any? Indicate whether high, middle, or low-income housing. b.Approximately how many units, if any, would be eliminated? Indicate whether high, middle, or low- income housing. c.Proposed measures to reduce or control housing impacts, if any: 10. Aesthetics [help] a.What is the tallest height of any proposed structure(s), not including antennas; what is the principal exterior building material(s) proposed? b.What views in the immediate vicinity would be altered or obstructed? c.Proposed measures to reduce or control aesthetic impacts, if any: 11.Light and Glare [help] a.What type of light or glare will the proposal produce? W hat time of day would it mainly occur? 291 of 347 b.Could light or glare from the finished project be a safety hazard or interfere with views? c.What existing off-site sources of light or glare may affect your proposal? d.Proposed measures to reduce or control light and glare impacts, if any: 12.Recreation [help] a.What designated and informal recreational opportunities are in the immediate vicinity? b.Would the proposed project displace any existing recreational uses? If so, describe. c.Proposed measures to reduce or control impacts on recreation, including recreation opportunities to be provided by the project or applicant, if any: 13.Historic and Cultural Preservation [help] a.Are there any buildings, structures, or sites, located on or near the site that are over 45 years old listed in or eligible for listing in national, state, or local preservation registers ? If so, specifically describe. b.Are there any landmarks, features, or other evidence of Indian or historic use or occupation? This may include human burials or old cemeteries. Are there any material evidence, artifacts, or areas of cultural importance on or near the site? Please list any professional studies conducted at the site to identify such resources. c.Describe the methods used to assess the potential impacts to cultural and historic resources on or near the project site. Examples include consultation with tribes and the Department of Archeology and Historic Preservation (DAHP), archaeological surveys, historic maps, GIS data, etc. d.Proposed measures to avoid, minimize, or compensate for loss, changes to, and disturbance to resources. Please include plans for the above and any permits that may be required. 14.Transportation [help] a.Identify public streets and highways serving the site or affected geographic area and describe proposed access to the existing street system. Show on site plans, if any. b.Is the site or affected geographic area currently served by public transit? If so, generally describe. If not, what is the approximate distance to the nearest transit stop? 292 of 347 c.How many additional parking spaces would the completed project or non-project proposal have? How many would the project or proposal eliminate? d.Will the proposal require any new or improvements to existing roads, streets, pedestrian, bicycle or state transportation facilities, not including driveways? If so, generally describe (indicate whether public or private). e.Will the project or proposal use (or occur in the immediate vicinity of) water, rail, or air transportation? If so, generally describe. f.How many vehicular trips per day would be generated by the completed project or proposal? If known, indicate when peak volumes would occur and what percentage of the volume would be trucks (such as commercial and nonpassenger vehicles). What data or transportation models were used to make these estimates? g. Will the proposal interfere with, affect or be affected by the movement of agricultural and forest products on roads or streets in the area? If so, generally describe. h. Proposed measures to reduce or control transportation impacts, if any: 15. Public Services [help] a.Would the project result in an increased need for public services (for example: fire protection, police protection, public transit, health care, schools, other)? If so, generally describe. b.Proposed measures to reduce or control direct impacts on public services, if any. 16. Utilities [help] a. Check utilities currently available at the site:  electricity,  natural gas,  water,  refuse service,  telephone,  sanitary sewer,  septic system,  other b.Describe the utilities that are proposed for the project, the utility providing the service, and the general construction activities on the site or in the immediate vicinity which might be needed. C. Signature [help] Signature: Name of Signee: Position and Agency/Organization: Date Submitted: 293 of 347 SEPA In response to section 3.2 (Water) of the SEPA checklist. The project site is located within the City's Type 1 Aquifer Recharge Areas (Groundwater Protection Zone 2). The following protective measures will be implemented as part of the project to ensure the groundwater is protected from potential contaminate created by the project. 1. Type I Aquifer Recharge Areas. a. Indicate how hazardous substances shall be stored and used such that any unauthorized release or discharge of the hazardous substances is prevented. The Spill Prevention, Control, and Countermeasures (SPCC) Plan will be required as part of the construction contract. The Contractor shall prepare the SPCC Plan and implement the plan for the duration of the project. The SPCC Plan shall address storage, containment, prevention, reporting and cleanup of all fuels, petroleum products, hazardous materials, and other materials. b. Specify that pesticides, herbicides, and fertilizers shall be applied in strict conformance with manufacturer’s instructions and by persons licensed to perform such applications, if applicable. As part of the contract, if pesticides and herbicides are needed, there shall be a plan and the plan shall be prepared and signed by a licensed Commercial Pest Control Operator or Consultant. The contract also stated the Contractor shall apply fertilizer in the form, mixture, and rate specified in the Special Provisions. Application procedures shall be in accordance with the manufacturer’s recommendations unless otherwise specified in the Special Provisions. c. Document hazardous substances management procedures, including, but not limited to, operations plans, drawings and as-built diagrams, emergency response and spill cleanup plans, and employee training documentation. This information can be provided in the form of copies of permits or other documentation required by other authorities. The Spill Prevention, Control, and Countermeasures (SPCC) Plan will be required as part of the construction contract. The Contractor shall prepare the SPCC Plan and implement the plan for the duration of the project. The SPCC Plan shall address storage, containment, prevention, reporting and cleanup of all fuels, petroleum products, hazardous materials, and other materials. d. Indicate that any fill material shall be documented to be free of contaminants that exceed Method A and Method B soil cleanup standards specified in Chapter 173- 340 WAC prior to placement on the ground, if applicable. The project’s Special Provisions will note that any fill material shall be free of contaminants. 294 of 347 e. Specify that any contaminant release reported to the Washington State Department of Ecology (Ecology) per Chapter 173-340 WAC shall also be reported to the city of Auburn public works department concurrent with notification of Ecology. The SPCC Plan will include the “Spill Reporting” section, which have the names and telephone numbers of the Federal, State, and local agencies to notify in the event of a spill f. Include a provision that the implementation of the protective measures will be maintained during the life of the project. Updates shall occur whenever there is a change in use or business occupancy or when there are significant changes in facility operations or hazardous substances management. A copy of the plan is to be available for review by city inspectors at the business or businesses within the development. The plan should cover the facility site in general as well as have a section(s) specific to any tenants within the development. The SPCC Plan will include implementing requirements where the Contractor shall update the SPCC Plan throughout project construction so that the written plan reflects actual site conditions and practices. The Contractor shall update the SPCC Plan at least annually and maintain a copy of the updated SPCC Plan on the project site. The Contractor shall fully implement the SPCC Plan, as accepted and updated, at all times. 295 of 347 296 of 347 SCALE: 1" = 30' SITE PLAN SCALE IN FEET 0 30 601530 (1" = 30')N 297 of 347 N 298 of 347 299 of 347 EXHIBIT 10 300 of 347 301 of 347 302 of 347 303 of 347 304 of 347 305 of 347 306 of 347 307 of 347 308 of 347 309 of 347 310 of 347 311 of 347 312 of 347 313 of 347 314 of 347 315 of 347 316 of 347 317 of 347 318 of 347 319 of 347 320 of 347 321 of 347 322 of 347 323 of 347 324 of 347 325 of 347 326 of 347 327 of 347 328 of 347 329 of 347 330 of 347 331 of 347 332 of 347 333 of 347 334 of 347 335 of 347 336 of 347 337 of 347 1 Dinah Reed From:Steven Sturza Sent:Tuesday, May 30, 2023 4:46 PM To:Dinah Reed Subject:FW: FDP22-0009 CIP2022 Garden Ave Realignment; Floodplain Permit Exemption FYI CODE QUESTIONS? Book an online meeting: Virtual Permit Center - City of Auburn (auburnwa.gov) Steve Sturza, P.E., CFM Development Engineer Manager City of Auburn Department of Community Development Direct: (253) 876-1969 Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Click Here for Map) Customer Service Survey | Application Forms | Zoning Maps From: Steven Sturza <ssturza@auburnwa.gov> Sent: Monday, February 6, 2023 8:32 AM To: Kim Truong <kbtruong@auburnwa.gov> Cc: Alexandria Teague <ateague@auburnwa.gov>; Development <Development@auburnwa.gov> Subject: FDP22-0009 CIP2022 Garden Ave Realignment; Floodplain Permit Exemption Good morning Kim, This email is to confirm that City of Auburn Capital Improvement Project CP2022 Garden Ave Realignment project outlined in the submittal documents for FDP22-0009 meet the criteria for exemption from a Floodplain Permit. The applicable exemption is found in ACC 15.68.370 (E), (F) and (G): Underground and above ground utility work located in previously disturbed areas, with no significant vegetation impacts, and will have no appreciable change in grade; Normal maintenance and preservation of public streets and private streets or parking lots (with approval of floodplain administrator), including, but not limited to, filling potholes, patching, crack seal, chip seal, repaving and installing signs and traffic signs, traffic control devices, striping/channelization, pavement markings, repair/replacement of sidewalk/curb and gutter, ADA improvements, nonmotorized improvements, repair of guardrails, repair of retaining walls, management of hazardous trees, fencing repair, lighting repair, but not including expansion of paved areas; Public street improvements with no significant vegetation impacts, and no appreciable change in grade; The capital project CP2022 – Garden Ave Realignment will fully construct SE 318th St with roadway, sidewalk, and curb and gutter connecting Garden Ave to 104th Ave. The project will also construct half-street improvements along the east side of Garden Ave with a cul-de-sac at the end of Garden Ave cutting off direct connection onto 8th St. Underground utilities improvements with associated appurtenances are also proposed with the project. The project area is within a developed right-of-way. There are currently existing paved streets and very little native vegetation. The project limit is not within the Riparian Buffer Zone (RBZ) or Special Flood Hazard Area. The project does extend into the Channel Migration Zone, however it meets the nondevelopment criteria above. 338 of 347 EXHIBIT 11 2 The above is consistent with the applicable City code’s definition of a nondevelopment activity and is therefore exempt from requiring a Floodplain Permit per ACC 15.68.160. This exemption is applicable to the activities provided in the application for FDP22-0009. Please let me know if there are any questions. Thank you, CODE QUESTIONS? Book an online meeting: Virtual Permit Center - City of Auburn (auburnwa.gov) Steve Sturza, P.E., CFM Development Engineer Manager | City of Auburn Department of Community Development Direct: (253) 876-1969 | ssturza@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Click Here for Map) Customer Service Survey | Application Forms | Zoning Maps 339 of 347 SCALE: 1" = 30' SITE PLAN SCALE IN FEET 0 30 601530 (1" = 30')N 340 of 347 EXHIBIT 12 N 341 of 347 1 Dinah Reed Subject:FW: Neighbor Comment - Garden Ave Realignment Dinah Reed, Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov Office 253-931-3092 | DReed@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Click Here for Map) Customer Service Survey | Application Forms | Zoning Maps Planning or Land Use Questions? Book an online meeting: Virtual Permit Center - City of Auburn (auburnwa.gov) From: Dinah Reed Sent: Thursday, June 8, 2023 5:40 PM To: jaleneking16@gmail.com Subject: FW: Neighbor Comment - Garden Ave Realignment Good afternoon Jalene, I forwarded your comment related to the Garden Avenue Realignment project to Jacob Sweeting, P.E., City Engineer/Assistant Director Engineering Services – so that he could respond. Your questions/comments were not necessarily directed toward Planning zoning and policies with regard to the Shoreline Substantial Development Permit (SHL22-0001) so I thought it would be best for him to reply. His response is below. Best regards, Dinah Reed Dinah Reed, Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov Office 253-931-3092 | DReed@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Click Here for Map) Customer Service Survey | Application Forms | Zoning Maps Planning or Land Use Questions? Book an online meeting: Virtual Permit Center - City of Auburn (auburnwa.gov) 342 of 347 EXHIBIT 13 2 From: Jacob Sweeting <jsweeting@auburnwa.gov> Sent: Thursday, June 8, 2023 5:12 PM To: Dinah Reed <DReed@auburnwa.gov> Cc: Kim Truong <kbtruong@auburnwa.gov>; James Webb <jwebb@auburnwa.gov> Subject: Neighbor Comment - Garden Ave Realignment PW Staff Response for Hearing Examiner Staff Report to Jalene King’s comment: Regarding the comment from Jalene King “All this new road is going to do for us is create much more traffic directly on our street as you are re-routing everyone on Garden Ave over to 104th. Why would we want that?”, City Staff have the following response: The Garden Avenue Realignment project will close the connection of Garden Avenue (also called 102nd Ave SE) to Lea Hill Road (also called 8th Street NE) and create a new roadway connection to 104th Ave SE. The idea for the project came about after the City annexed the remainder of Lea Hill from King County in 2008 and the City observed that increasing traffic on Lea Hill Road was creating traffic operational concerns at the Garden Avenue intersection. The project was further developed through the Lea Hill Road Corridor Study completed in 2020. The intersection of Garden Avenue and Lea Hill Road has the following issues: It is very close to the signalized intersection of 104th Ave SE (approximately 390 feet), is directly adjacent to the Green River Bridge, and is at a location where lane shifts and transitions are occurring. There is also a Metro bus stop between Garden Avenue and 104th Ave SE. The Garden Avenue approach to Lea Hill Road is steep and without a landing at the intersection. These conditions contribute to the following undesirable effects: 1) Cars backed up at the 104th Ave SE intersection block the Garden Avenue intersection. 2) Cars turning from Lea Hill Road to Garden Avenue block traffic and keep traffic from approaching or departing the signal, which degrades the signal’s effectiveness and increases delays. 3) Cars turning left or right from Garden Avenue to Lea Hill Road have few gaps to make their turns and experience frequent delays. The new connection of Garden Avenue to 104th Ave SE (at the location of SE 318th Street currently constructed as an access road) will be sufficiently spaced from the intersection of Lea Hill Road (approximately 580 feet), is not constrained by the Green River Bridge, is not at a location where lane shifts and transitions are occurring, is not near Metro bus stops, does not have approach grade issues and allows for an appropriate intersection landing. For these reasons, the new connection of Garden Avenue is expected to be more functional than the current connection of Garden Avenue to Lea Hill Road. Thanks, Jacob Sweeting, P.E. City Engineer/Assistant Director Engineering Services Public Works Dept., City of Auburn, WA 253-804-3118 jsweeting@auburnwa.gov From: Jalene King <jaleneking16@gmail.com> Sent: Tuesday, May 23, 2023 9:50 PM To: Planning-1 <Planning@auburnwa.gov> Cc: Darrell King <darrell.king@pcg.com>; jazzyjj7@msn.com Subject: Garden Ave Realignment 343 of 347 3 CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments I wish to receive notice of and participate in any hearings, request a copy of decisions once made, and be made aware of appeal rights. I will be attending the Public Hearing on June 21, 2023 at 5:30. Here are my comments to be shared: I want to make it publicly known that I think forcing three homeowners to pay 10% of the total cost for a road project that none of us want is very unfair and shows what little you care about your residents. The fact that you would allow a builder to pass on that kind of expense to his buyers unknowingly is also very shady. On September 1, 2022 City Engineer Jacob Sweeting admitted to us that the City no longer grants Deferrals such as this because of what it does to the homeowner aka the “little guy”. All this new road is going to do for us is create much more traffic directly on our street as you are re-routing everyone on Garden Ave over to 104th. Why would we want that? You have been no help to us over the years with the dozen times our fence, vehicles, and property have been hit by drunk drivers and now you are forcing us to pay for a project that doesn’t benefit us. It bewilders me how you can sleep at night while you are knowingly hurting members of your community. Jalene King 10387 SE 318th St. Auburn, WA 98092 253-334-5104 344 of 347 1 Dinah Reed Subject:FW: Public comment Garden Ave realignment Project Dinah Reed, Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov Office 253-931-3092 | DReed@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Click Here for Map) Customer Service Survey | Application Forms | Zoning Maps Planning or Land Use Questions? Book an online meeting: Virtual Permit Center - City of Auburn (auburnwa.gov) From: Dinah Reed Sent: Tuesday, June 13, 2023 2:34 PM To: Z. M. <Lethiathan@msn.com>; Planning-1 <Planning@auburnwa.gov> Subject: RE: Public comment Garden Ave realignment Project Dear Mr. Murphy, Below is staff response to your comment regarding SHL22-0001 for the Garden Avenue realignment project. Your comment will be included as an Exhibit for the Hearing and you have been included as a Party of Record. PUBLIC WORKS RESPONSE The proposed sidewalk is a required street element per the City’s adopted Engineering Design Standards (EDS) and is in accordance with ACC 12.64A, required improvements. Per the City’s Comprehensive Transportation Plan, 318 th Street SE and Garden Avenue/102nd Ave SE are classified as a local residential streets. The EDS requires local residential streets to include curb and gutter, a 5.5 foot wide landscaping strip with street trees, and a 5 foot sidewalk on both sides of the street or, alternatively, curb and gutter, a 7 ½ foot wide sidewalk on one side of the street and a 5 foot wide sidewalk on the other side of the street with an 8 foot wide landscaped area to accommodate low-impact-development storm facilities such as a bioretention swale. Sidewalks are included to provide non-motorized access to adjacent properties and to provide active transportation connectivity consistent with local, state, and regional planning requirements. This is consistent with, and supported by, the Complete Street Ordinance adopted by City Council in 2016. The sidewalks included in the Garden Avenue project will create a complete connection between 104 th Avenue SE with 102nd Avenue SE to the west, which in turn will connect with the existing sidewalk on 8 th Street NE/Lea Hill Road to the south along 102nd Ave/Garden Ave. This provides sidewalk connectivity to and across the Lea Hill Bridge. This in turn connects this residential neighborhood to commercial areas, public parks, and services including transit services on 8 th Street NE/Lea Hill Road. The 8th Street NE/Lea Hill Road Corridor is also identified in Metro’s Transit Connects Plan as a future Rapid Ride Corridor with frequent service intended to serve the neighborhoods along the corridor furthering the local and regional planning goals of non-motorized connectivity to transit services. 345 of 347 EXHIBIT 14 2 In addition, the City has a roundabout project at the Lea Hill Road/104 th Avenue SE intersection currently in design. This project includes the extension of the sidewalk along the west side of 104 th Avenue SE and the north side of 8th Street NE/Lea Hill Road to meet the sidewalk being constructed with the Garden Avenue project. This will further extend the existing sidewalk network providing access to additional properties. This is the first phase of a number of projects identified to improve the Lea Hill Road Corridor, which includes the creation of a non-motorized connection between the Auburn Valley and Lea Hill area including the crossing of the Green River which is a barrier to connectivity. As properties develop or redevelop, ACC 12.64A requires that frontage improvements be completed with the development, this project completes sidewalks where previous commitments are in place from past development and completes sidewalks across the City owned properties to complete the connections noted above. In addition, recent state legislation and adopted regional planning policies require the implementation of more active transportation and transit services within residential areas which requires the completion of sidewalks to meet planning goals within the urban growth management boundaries and provide the necessary connectivity between properties and transit services. PLANNING RESPONSE The “Urban Separator” designation has its origins in the King County, Countywide Planning Policies, as they are incorporated and implemented by the City of Auburn’s Comprehensive Plan (Volume 1, Land Use, Policies LU-122 and LU-123). This is a policy document and there is no direct regulation of land use by King County. The purpose of the Urban Separator areas are to designate low-density residential uses, as evidenced by the city’s R-1, Residential, one dwelling unit per acre zoning applicable to the area north of 8th Street NE/SE 320th Street. In addition, the purpose includes protection of the environmentally sensitive areas, which in this location is the shoreline of the Green River. While you describe the area as “rural”, all of the land within the City of Auburn is located within the “Urban Growth Area” and is officially designated “urban” and not “rural”. Urban areas are meant to be served by an urban level of improvements and services. While your comments suggest not including a sidewalk, including a sidewalk along Garden Avenue promotes non- motorized access in and around the shoreline and viewing of the shoreline which is consistent with policies of the city’s Shoreline Management Plan, as stated in Policy SMP 3.3.3(3) “Public access and public recreation objectives should be implemented whenever feasible and significant ecological impacts can be mitigated.” Dinah Reed, Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov Office 253-931-3092 | DReed@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Click Here for Map) Customer Service Survey | Application Forms | Zoning Maps Planning or Land Use Questions? Book an online meeting: Virtual Permit Center - City of Auburn (auburnwa.gov) From: Z. M. <Lethiathan@msn.com> Sent: Wednesday, June 7, 2023 1:14 PM To: Planning-1 <Planning@auburnwa.gov> Subject: Public comment Garden Ave realignment Project 346 of 347 3 CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Hello, I wish to submit my public comment for record and be included on all notices, decisions and appeal rights for the Garden Avenue realignment Project. I support the closure and construction of 318th as I believe this will provide the general public much needed safety and capacity improvements. I support the enhanced vegetation planting and incorporating as much natural elements as possible. I oppose the current design incorporating sidewalks for the entire project. The impacted subdivision is classified as urban separators under the King County planning policies and should be retained as a visual break between urban Auburn and the very rural nature of 104th, thus not include sidewalks. There a very little benefits for the taxpayers to pay for sidewalks which are not connected to any other continuous sidewalk. We should keep the surrounding area as is to provide a transition visual contrast point to rural Auburn and thereby retaining the unique identity of this community. Thanks, Zac Murphy 347 of 347