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Home My WebLink About10-16-2019 HE Packet 10.16.19 Copper RidgeHEARING EXAMINER October 16, 2019 5:30 p.m. City Council Chambers 25 West Main Street I.Case No:PLT18-0004, Copper Ridge Preliminary Applicant(s):Evan Mann Entitlement Manager Soundbuilt Northwest PO Box 73790 Puyallup, WA 98373 Property Owner: Paul Sloan 29255 59th Ave S. Auburn, WA 98001 Susan Wilkes 29242 59th Ave S. Auburn, WA 98001 Request: Preliminary plat application to subdivide approximately 4.77 acres into 19 single-family residential lots. The site is zoned R-5, Residential, which allows 5-7 dwelling units per acre. The proposed lots range in size from approximately 4,200 sq. ft. to 8,600 sq. ft. Roadways to be constructed include the on-site approximately 200-foot extension of 58th Ave. S. north from S.294th St. as a cul-de-sac and two private access tracts. Utility lines will be extended within the on-site public street and private access/utility tracts to serve the lots. Two open space tracts are proposed to contain the on-site wetlands and stream. Project Location: The project site is located at the northeast corner of S. 294th St. and 59th Ave S within NW ¼ of Section 2, Township 21, Range 4. Parcel Number(s): 0221049071 and 0221049044 1 of 291 AGENDA BILL APPROVAL FORM HEARING EXAMINER Agenda Subject/Title: PLT18-0004, Copper Ridge Preliminary Plat Date: October 1, 2019 Department: Community Development Budget Impact: Current Budget: $0 Proposed Revision: $0 Revised Budget: $0 DESCRIPTION: Preliminary plat application to subdivide approximately 4.77 acres into 19 single-family residential lots in the R-5, Residential Zoning District. ADMINISTRATIVE RECOMMENDATION: Hearing Examiner to conduct a public hearing and approve the Copper Ridge Preliminary Plat application with 20 conditions including two (2) Deviation requests related to Engineering Design Standards. PROJECT SUMMARY: Preliminary plat application to subdivide approximately 4.77 acres into 19 single-family residential lots. The site is zoned R-5, Residential, which allows 5-7 dwelling units per acre. The proposed lots range in size from approximately 4,200 sq. ft. to 8,600 sq. ft. Roadways to be constructed include the on-site approximately 200-foot extension of 58th Ave. S. north from S. 294th St. as a cul-de-sac and two private access tracts. Utility lines will be extended within the on-site public street and private access/utility tracts to serve the lots. Two open space tracts are proposed to contain the on-site wetlands and stream. LOCATION: The project site is located at the northeast corner of S 294th St. and 59th Ave. S., within NW ¼ of Section 2, Township 21, Range 4. King County Assessor Parcel Nos. 0221049071 and 0221049044. APPLICANT(S): Evan Mann, Entitlement Manager, Soundbuilt Northwest, PO Box 73790, Puyallup, WA 98373 APPLICANT’S REPRESENTATIVE: Evan Mann, Entitlement Manager, Soundbuilt Northwest, PO Box 73790, Puyallup, WA 98373 PROPERTY OWNER(S): Paul Sloan, 29255 59th Ave. S, Auburn, WA 98001 and Susan Wilkes, 29242 Ave. S, Auburn, WA 98001 2 of 291 Staff Member: Gouk Date: October 1, 2019 Page 2 of 22 Subject Property and Adjacent Property Comprehensive Plan Designation, Zoning Classification and Current Land Use: Comprehensive Plan Designation Zoning Classification Current Land Use Project Site Single Family R-5 Residential Zone Single-family residences and associated accessory structures North Single Family R-5 Residential Zone Single-Family Residences South Single Family; Institutional R-5 Residential Zone Single-Family Residences; COA Stormwater Detention Facility East Single Family R-5 Residential Zone Single-Family Residences West Single Family R-5 Residential Zone Single- Family Residences Excerpted Zoning Map: 3 of 291 Staff Member: Gouk Date: October 1, 2019 Page 3 of 22 Excerpted Comprehensive Plan Map: 2017 Aerial Vicinity Map: 4 of 291 Staff Member: Gouk Date: October 1, 2019 Page 4 of 22 Street Layout Map: SEPA STATUS: A Determination of Non-Significance (DNS) was issued under City File No. SEP18-0017 on August 14, 2019, see Exhibit 4. The comment period ended August 29, 2019 and the appeal period ended September 12, 2019. Four written comments were received. The comments received along with the City responses are included as Exhibit 5. No appeal of the SEPA decision was received. FINDINGS OF FACT: Preliminary Plat Findings 1. Evan Mann, Entitlement Manager, with Soundbuilt Homes, on behalf of Paul Sloan and Susan Wilkes, Property Owners, submitted a Preliminary Plat application and associated SEPA application on July 31, 2018 to subdivide approximately 4.77 acres (referred to in this Staff Report as the “Site”) into 19 single-family residential lots, two new private access/utility tracts stemming from 58th Ave. S (Tracts A and D), two private open space tracts (Tract C and E), and one publicly-dedicated stormwater vault tract (Tract B), referred to in this Staff Report as the “Project”. Access to the Site will be via S. 294th St./58th Ave. S from 59th Ave. S. (Note, in some documents the project is titled “West Hill Plat” or “Soundbuilt Homes Plat”.) 5 of 291 Staff Member: Gouk Date: October 1, 2019 Page 5 of 22 2. The Site consists of two parcels and is located in the West Hill portion of the City, directly north of S 294th St. and west of 59th Ave. S. The Site is located within the City of Auburn’s corporate limits, and referenced by King County Tax Assessor Parcel Nos. 022104-9071 and 022104-9044. 3. The Site has a Comprehensive Plan designation of “Single Family Residential” and is zoned R-5, Residential, Five Dwelling Units Per Acre, which has a density range of between 4 and 5 dwelling units per acre. The site is approximately 4.77 acres, which in accordance with the density calculation would require between 18.8 (rounded to 19) and 23.85 (rounded to 24) lots respectively per Auburn City Code (ACC) 18.02.065(A)(1)(a). 4. The Project is subject to the zoning development standards for the R-5 zoning district in effect at the time the Project application was considered “Complete” (i.e. vested). Per ACC 18.07.030 the zoning development standards for the R-5 zoning district include:  Minimum lot area: 4,500 square feet  Minimum lot width: 50 feet  Lot coverage: 40%  Impervious surface: 65%  Maximum building height: 35 feet  Minimum yard setbacks: o Front: 10 feet o Side, interior: 5 feet o Side, street: 10 feet o Rear: 20 feet 5. Per ACC 18.52.020 two off-street parking spaces per single family residence is required. 6. The Site currently features a single family residence on each of the two lots with accessory structures (sheds). The homes and associated accessory structures will be demolished. The site is currently served with water and sewer service by Lakehaven. 6 of 291 Staff Member: Gouk Date: October 1, 2019 Page 6 of 22 7. The Site is rectangular in shape, as shown and dimensioned here: 8. The Site is bordered by an existing “Local Residential” classified street to the east (59th Ave. S), and a “Local Residential” classified street (S 249th St.) to the south. The off-site portion of 58th Ave. S is classified as a “Local Residential” intersects the midpoint of the south boundary of the Site. 58th Ave. S will be extended through the Project with full public street improvements meeting “Local Residential” standards, and terminate in a cul-de-sac. Two new private access tracts (Tracts A and D) will radiate from 58th Ave S. For full size plans, see Exhibit 6. 9. The Site is located within the utility service areas of, and will be served by, Lakehaven Water & Sewer District for public water and sewer. 10. The Site slopes gradually from west to east, with areas containing slopes of 25% or greater occurring in the north-central, southwestern, and eastern portions of the Site. With the exception of the area along the eastern portion of the site, these areas will be placed into open space tracts (Tracts C and E). The area on the eastern side (adjacent to 59th Ave. S will be graded and be retained with a combination of a retaining wall and the outer wall of the proposed stormwater vault. 11. The Site is located within the critical area of Groundwater Protection Zone 4, the least stringent classification. Therefore no impacts are anticipated that cannot be mitigated by utilizing Best Management Practices (BMPs). As recommended in the Preliminary Stormwater Report (Exhibit 9), stormwater runoff from the Project will be treated and 630.82 ft. 630.94 ft. 329.54 ft. 329.65 ft. 7 of 291 Staff Member: Gouk Date: October 1, 2019 Page 7 of 22 detained in a stormwater detention facility (“stormwater vault”) located in Tract E, per the Department of Ecology Stormwater Management Manual for Western Washington (SWMMWW) and Auburn Supplements. 12. The Site is not located within any shoreline designation. 13. The Site is not located in the regulatory floodplain per Federal Emergency Management Agency (FEMA) maps. 14. Two wetlands (Wetland A and Wetland D (note that Wetland “D” is also referred to as Wetland “B” in some pages of the reports/plans) and a stream (Mullens Creek) have been identified on the Site (reference the Critical Areas Report, Exhibit 7). Both wetlands have been rated as Category III wetlands which have a minimum buffer of 25 ft. per the city’s critical areas regulations, Chapter 16.10 ACC. The Department of Natural Resources Forest Practices Application Review System (DNR FPARS) has identified Mullens Creek as a non- fish bearing or Type N stream as there is a gradient that is non-passable to fish offsite to the northeast. Wetlands A, D, Mullens Creeks, and their buffers will be placed within open space tracts for permanent preservation (Tracts C and E). Access to the Tracts for inspections and monitoring will be required and determined prior to civil plan (FAC) approval, as conditioned below. 15. There are occupation features (apparent property line encroachments) along the northeast boundary of the Site (i.e. fences and walls) affecting the boundary between the subject site and adjoining parcels, which are shown and appropriately dimensioned. Any potential adverse claims and/or unwritten rights associated with the depicted occupation features is a civil matter between private parties. During the civil plan review process, any encroaching fence or wall will need to be relocated or an easement granted to the occupation feature owner. The City’s review of this preliminary plat application is for its conformity to Auburn City Code and state platting law, and as such does not address nor adjudicate any potential unwritten rights that may be acquired by the Applicant or the adjoiners. The project is conditioned such that a note will be required on the Final Plat if these remain unchanged and/or unresolved at the time of final plat application. 16. Half-street improvements will be required to 59th Ave S. including the dedication of approximately 7 ft. of right-of-way (ROW), curb, gutter, sidewalks, street lighting, stormwater controls, and landscape strips to meet the City’s “Local Residential” standard. The same half street improvements are also required for S. 294th St., however, dedication of approximately 13.5 ft. of ROW is required. Additional ROW at the corner of S. 294th St. and 59th Ave. S will be required to include adequate area for intersection radius associated with the half street improvements. 17. Construction shall occur between the hours of 7 AM and 7 PM on weekdays, and between 9 AM and 6 PM on Saturday and Sunday per City regulation (ACC 8.28.010(B)(8)). 18. The current park impact fee shall be assessed at the time of building permit issuance, unless a different timing is requested and granted in accordance with Chapter 19.08 ACC ‘Parks Impact Fees’. 8 of 291 Staff Member: Gouk Date: October 1, 2019 Page 8 of 22 19. The current school impact fee shall be assessed at the time of building permit issuance, unless a different timing is requested and granted in accordance with Chapter 19.02 ACC ‘School Impact Fees’. 20. The current fire impact fee shall be assessed at the time of building permit issuance, unless a different timing is requested and granted in accordance with Chapter 19.06 ACC ‘Fire Impact Fees’. 21. The current traffic impact fee shall be assessed at the time of building permit issuance, unless a different timing is requested and granted in accordance with Chapter 19.04 ACC ‘Transportation Impact Fees’. 22. A combined Notice of Application, Notice of Public Hearing, and Determination of Non- Significance (DNS), was issued on August 14, 2019 (Exhibit 4). The notices were posted at the Site, mailed to property owners within 300 ft. of the Site, and published in The Seattle Times newspaper. 23. In response to the public notice the City received four comment letters as of October 2, 2019 (the date this Staff Report was finalized) on the project. The following is an abbreviated list of the comment(s) along with a short summary of the City’s response, if one was necessitated. Copies of the full comments and responses are included as Exhibit 5. a. Mary Jo Tarbuck, 29412 58th Ave. S: expressed concerns with increase traffic and impacts to the environment including the wetlands, stream, and wildlife. City Response: Staff’s response indicated that the wetlands and stream would be set aside as permanently protected areas. b. Mary Beth Dahl, 29417 58th Ave. S: expressed concerns with preservation of the wetlands and streams and their buffers. City Response: no response was provided. c. Karen Walters, Muckleshoot Indian Tribe (MIT) Fisheries Division: questioned the accuracy of the stream classification (fish bearing or not), concerns with reducing wetland and stream buffers, and questioning why the project is not providing enhanced stormwater treatment. City Response: the Applicant provided a response to these comments clarifying that the stream is not fish bearing as there is a natural barrier (stream channel gradient) that makes the Site inaccessible for fish, that there is no proposed reduction in wetland or stream buffer widths (i.e. the buffers meet current City standards), and that modular wetlands (stormwater vault) will be provided which provide enhanced treatment. d. Katelynn Piazza, Department of Ecology (ECY): provided comments regarding potential soil contamination from the Asarco smelter in north Tacoma. City Response: no response was provided, the information was passed along to the Developer. 9 of 291 Staff Member: Gouk Date: October 1, 2019 Page 9 of 22 Engineering Deviation Findings 1. Three deviations for relief from the City of Auburn Engineering Design Standards (COADS) were applied for by the Applicant as follows: 1) utilization of a stormwater detention vault in place of a pond (City File No. DEV19-0010, Exhibit 11); 2) construction of a private access tract with a slope greater than 8% (DEV19-0019, Exhibit 12); and, 3) reduce the design speeds for the crest and sag curves for the proposed cul-de-sac (DEV19-0032, Exhibit 13). 2. The first request (DEV19-0010) is to construct a stormwater detention vault in lieu of a detention pond. The City Engineer has drafted (i.e. not yet published) requirements for allowing detention vaults through the Deviation process and the proposed vault meets these anticipated requirements, as conditioned below. City engineer is recommending approval. 3. The second request (DEV19-0019) was to construct the private access road within Tract A to a slope of 8.66%. This request was denied by the City Engineer based on the proposal not adequately meeting several safety factors and therefore does not require consideration by the Hearing Examiner. Note that the private access road has since been redesigned to meet this Design Standard. 4. The third request is to reduce the design speed for a crest curve from 30 MPH to 25 MPH and to reduce the sag curve design speed from 30 MPH to 15 MPH for 58th Ave. S. The City Engineer concludes that these requests are applicable to a dead-end cul-de-sac and is recommending approval. 5. Deviations from the COADS are subject to approval of the Hearing Examiner per ACC 17.18.010(A) which states (emphasis added): “A. The hearing examiner may approve a modification of any standard or specification established or referenced by Chapter 17.14 ACC or established or referenced in the city’s design standards or construction standards, upon making the findings of fact in ACC 17.18.030; provided, that the hearing examiner shall obtain the concurrence of the city engineer for any requests to modify any city of Auburn design or construction standard.” CONCLUSIONS: Preliminary Plat Conclusions Staff recommends approval of the Preliminary Plat, with conditions. Per ACC 14.03.030, a preliminary plat is a Type III Decision which are quasi-judicial final decisions made by the Hearing Examiner. ACC 17.10.070 ‘Findings of Fact’ lists the approval criteria for a preliminary plat. A comparison of the project’s relationship to subdivision approval criteria are as follows (in italics) followed by a Staff analysis: 10 of 291 Staff Member: Gouk Date: October 1, 2019 Page 10 of 22 A. Adequate provisions are made for the public health, safety and general welfare and for open spaces, drainage ways, streets, alleys, other public ways, water supplies, sanitary wastes, parks, playgrounds and schools; Staff Analysis: No adverse impacts to the public health, safety and general welfare are anticipated from the proposed subdivision. Staff offers the following analysis of each of subcategory listed in this criterion: Open Spaces: The Project is not subject to any park dedication, open space, or clustering requirements under Title 18 ‘Zoning’ or Title 17 ‘Land Adjustments and Divisions’. Drainage Ways: No existing drainage ways that are not regulated critical areas appear to be located on the Site. Through the civil plan review process, the stormwater runoff from the Project will be evaluated, treated, and detained in a stormwater vault located in Tract B and dispersed into the wetland buffers, consistent with the SWMMWW and Auburn Supplements. Streets, Alleys, other Public Ways: The Project will be required to construct streets per ACC, Chapter 12.64A ACC ‘Required Public Improvements’, the City’s Engineering Design Standards, and the Comprehensive Transportation Plan. With the extension of 58th Ave. SE into the site and the completion of the half street improvements along S. 294th St. and 59th Ave. S, the City’s Transportation Division finds that there will be no decrease in the road network level of service (LOS) standard. The Applicant will be required, however, to provide an intersection control evaluation showing what intersection controls are necessitated, if any, at the intersection of 58th Ave. S and S. 294th St.. Additionally, as provided in ‘Finding of Fact’ No. 21, each new residence will be required to pay the Traffic Impact Fee in place at time of building permit issuance. Two private access roads (within Tracts A & D) will be constructed off of the northern end of the cul-de-sac. Tract A will provide access for Lots 8- 10 and 11-13 and also provide a secondary emergency access onto 59th Ave. S; Tract D will provide access to Lots 14-16. Details of the road improvements, which are consistent with the COADS, as modified by DEV19-0032, are shown on Sheet 4 of 10 of the Preliminary Plat drawings (Exhibit 6). Based on the City’s Comprehensive Transportation Plan, Functional Roadway Classification Map, all public roadways that require improvements are classified as “Local Residential” streets. One transportation-related deviation has been requested to reduce the crest and sag curve design speeds for 58th Ave. S, which the City Engineer recommends for approval; reference the Engineering Deviation Findings and Conclusions, above and below, respectively. Public Water: The Site is located within the Lakehaven Utility District and will provide adequate water supplies to the Project. See Exhibit 14 for availability certificate. Public Sanitary Sewer: The Site is located within the Lakehaven Utility District and will provide adequate sewer service to the Project. See Exhibit 14 for availability certificate. Parks, Playgrounds: No parks or playgrounds are proposed for the Project and none are 11 of 291 Staff Member: Gouk Date: October 1, 2019 Page 11 of 22 required under City Code authority. Per ‘Finding of Fact’ No. 18, Park Impact Fees will be paid at the time of building permit issuance (currently $3,500.00 per unit). There are no formal parks within ½ mile of the site, however, informal recreational opportunities are available in the area including Meredith Hill Elementary (approx. 0.7 mile walk) and the open space tracts within the Project. Per the City’s Parks Department, development of a new community park within the West Hill portion of the City is an ongoing process. The fees from the homes in this development will add to the funds available for purchasing park land and eventual development of a park. Schools: The Site is located within the Federal Way School District boundary. Per the Applicant, students within the Project will attend: 1) Meredith Hill Elementary School; 2) Kilo Middle School, and 3) Thomas Jefferson High School. Students will be bussed from a bus stop located near the intersection of 59th Ave. S and S. 294th St. to their respective schools. Students will have two options to walk to the bus stop (via sidewalks constructed with this project); 1) travel south on 58th Ave. S then west on S. 294th St. to the stop at 59th Ave. S; or 2) via the sidewalk within Tract A to 59th Ave. S then south along 59th to the stop at S. 294th St. It is unclear if the bus stop is located on the east or west side of 59th Ave. S (the Federal Way School District was provided with the public notice but did not provide a response). For additional school transportation details, see Exhibit 10. Staff therefore finds the Project meets this criterion, as conditioned herein. B. Conformance of the proposed subdivision to the general purposes of the comprehensive plan; Staff Analysis: The Project is consistent with the general purposes of the Comprehensive Plan. The Comprehensive Plan Map establishes the future land use designations for the City of Auburn. The designation of ‘Single Family Residential’ establishes areas intended for single family dwellings. The Comprehensive Plan Map depicts the Site as ‘Single Family Residential’. The Project will subdivide approximately 4.77 acres into 19 lots for single family dwellings. Therefore this Project meets the intent of the Comprehensive Plan by developing single family dwellings. Additionally, adequate City services / facilities and water / sewer service (Lakehaven) can be provided to serve the plat. The Project will also provide adequate facilities for stormwater; stormwater will be directed to the stormwater detention vault and the dispersion trenches. The stormwater facilities will be required to meet applicable code and engineering design standards, as conditioned below. 58th Ave .S, a “Local Residential” public street will be extended into the Site to serve the proposed Project. Sidewalks will be constructed on both sides of the 58th Ave. SE as well as along the project frontages on S. 294th St. and 59th Ave. S. The Project will connect pedestrians to 59th Ave. S via Tract A and 58th Ave. S. Public services such as the Auburn Police Department, Valley Regional Fire Authority, and the Federal Way School District will also serve the proposed Project. The Project will utilize a school bus stop located at the intersection of S. 294th St. and 59th Ave. S. Finally, impact fees for traffic, fire, parks, and schools will mitigate respective impacts generated by the Project. The Project is also consistent with or implements the specific following goals, objectives, and policies of the Comprehensive Plan: 12 of 291 Staff Member: Gouk Date: October 1, 2019 Page 12 of 22 Land Use Policies: “LU-5 New residential development should contribute to the creation, enhancement and improvement of the transportation system, health and human services, emergency services, school system, and park system. This may be accomplished through the development of level of service standards, mitigation fees, impact fees, or construction contributions.” Capital Facilities “Objective 1.1. To ensure that new development does not out-pace the City's ability to provide and maintain adequate public facilities and services, by allowing new development to occur only when and where adequate facilities exist or will be provided, and by encouraging development types and locations which can support the public services they require.” Policies: “CF-1 Lands designated for urban growth by this Plan shall have an urban level of public facilities (sewer, water, storm drainage, and parks) prior to or concurrent with development.” “CF-2 Encourage development where new public facilities can be provided in an efficient manner.” “CF-4 If adequate facilities are currently unavailable and public funds are not committed to provide such facilities, developers must provide such facilities at their own expense in order to develop.” “CF-7 The City shall encourage and approve development only where adequate public services including police protection, fire and emergency medical services, education, parks and other recreational facilities, solid waste collection, and other governmental services are available or will be made available at acceptable levels of service prior to project occupancy or use.” “Objective 1.2. To ensure that new developments are supported by an adequate level of public services through an effective system of public facilities.” Policies: “CF-10 Public facilities shall be provided in accord with the guidance of the Capital Facilities Plan or, as may be appropriate a system plan for each type of facility designed to serve at an adequate level of service the locations and intensities of uses specified in this comprehensive plan.” “CF-12 No new development shall be approved which is not supported by a minimum of 13 of 291 Staff Member: Gouk Date: October 1, 2019 Page 13 of 22 facilities to support the development and which does not provide for a proportionate share of related system needs.” “Objective 1.3. To ensure safe and adequate water service, for both domestic and fire protection purposes, to meet the needs of the existing community and provide for its planned growth.” “CF-16 The City shall continue its policy of requiring that water system extensions needed to serve new development shall be built prior to or simultaneously with such development, according to the size and configuration identified by the Comprehensive Water Plan as necessary to serve future planned development. The location and design of these facilities shall give full consideration to the ease of operation and maintenance of these facilities by the City. The City shall continue to participate to the extent permitted by law, through direct participation, LIDs, and payback agreements, to assist in the financing of such oversized improvements. Wherever any form of City finance is involved in a waterline extension, lines that promote a compact development pattern will be favored over lines traversing large undeveloped areas with uncertain future development plans.” “Objective 1.4. To ensure the efficient transmission of sanitary sewage to the appropriate treatment and disposal facilities in order to meet the needs of the existing community and provide for its planned growth.” “CF-23 The City shall continue its policy of requiring that sewer system extensions needed to serve new development shall be built prior to or simultaneously with such development, according to the size and configuration identified by the Comprehensive Sewer Plan and Comprehensive Plan as necessary to serve future planned development. The location and design of these facilities shall give full consideration to the ease of operation and maintenance of these facilities by the City. The City shall continue to use, to the extent permitted by law, direct participation, LIDs and payback agreements to assist in the financing of such oversized improvements. Wherever any form of City finance is involved in a sewer line extension, lines that promote a compact development pattern will be favored over lines traversing large undeveloped areas where future development plans are uncertain.” “Objective 1.6. To ensure that collection, conveyance, storage and discharge of storm drainage is provided in a sufficient and environmentally responsible manner, in order to meet the needs of the existing community and provide for its planned growth.” Policies: “CF-37 The City shall require developers to construct storm drainage improvements directly serving the development, including any necessary off-site improvements.” Transportation Plan “Connect-01: An efficient transportation system seeks to spread vehicle movements over a series of planned streets. The goal of the system is to encourage connectivity while preventing unacceptably high traffic volumes on any one street. Ample alternatives should 14 of 291 Staff Member: Gouk Date: October 1, 2019 Page 14 of 22 exist to accommodate access for emergency vehicles. For these reasons the City will continue to plan a series of collectors and arterials designed to national standards to provide efficient service to the community.” “Funding-01: Require developments or redevelopments to construct transportation infrastructure systems needed to serve new developments.” “Funding-03: Improvements that serve new developments will be constructed as a part of the development process. All costs will be borne by the developer when the development is served by the proposed transportation improvements. In some instances, the City may choose to participate in this construction if improvements serve more than adjacent developments.” “Parking-02: New developments should provide adequate off-street parking to meet their needs.” “ROW-01: The acquisition and preservation of right-of-way is a key component of maintaining a viable transportation system. Methods used to acquire and preserve right-of- way include:  Requiring dedication of right-of-way as a condition of development;  Purchasing right-of-way at fair market value; and  Acquiring development rights and easements from property owners.” “Ped-03: Require developers to incorporate pedestrian facilities into new development and redevelopment in conformance with the Auburn City Code.” Parks, Recreation, and Open Space Plan “PR-8 Park impact fees should be established that help fund the future development of new parks, park facilities, trails, and acquisition of open space that meet the needs of an increasing population.” C. Conformance of the proposed subdivision to the general purposes of any other applicable policies or plans which have been adopted by the city council; Staff Analysis: The preceding analysis for Criterion B demonstrates the Project’s consistency with the applicable policies and objectives of the Comprehensive Plan adopted by the City. The project is generally consistent with the policies of the Comprehensive Plan including the City of Auburn Capital Facilities Plan, Comprehensive Transportation Plan, and the Parks, Recreation and Open Space Plan. D. Conformance of the proposed subdivision to the general purposes of this title, as enumerated in ACC 17.02.030; Staff Analysis: The proposed subdivision meets the general purposes of Title 17 ACC ‘Land Adjustments and Subdivisions’. The Project is a 19-lot subdivision that is consistent with the R-5 zoning district. Adequate provisions for water, sewer, storm drainage, roads, and safe walking conditions will be provided with this Project. The plat has been processed 15 of 291 Staff Member: Gouk Date: October 1, 2019 Page 15 of 22 and reviewed for conformity with the regulations of the Auburn City Code, City plans, policies, and engineering design standards. Below is a comparison of the Project’s consistency with ACC 17.02.030 and the specific purpose statements of the subdivision code (in italics) followed by a Staff analysis for each item. “The purpose of this title is to regulate the division of land lying within the corporate limits of the city, and to promote the public health, safety and general welfare and prevent or abate public nuisances in accordance with standards established by the state and the city, and to: A. Prevent the overcrowding of land; Staff Analysis: The Project meets the minimum and base density of the R-5 zoning district. As provided under ‘Finding of Fact’ No. 3, the R-5 zoning district has a density range of between 4 and 5 dwelling units per acre. As the site is approximately 4.77 acres, which based on the density calculation requires between 19 and 24 lots. As proposed, the Project will contain 19 lots, the minimum density for the R-5 zoning district. Therefore, the Project will not create an overcrowding of the land. B. Promote safe and convenient travel by the public on streets and highways; Staff Analysis: The Project is extending 58th Ave. S into the Site and constructing half street improvements to complete the roadway sections on S. 294th St. and 59th Ave. S and therefore will provide a means of safe and convenient travel via public routes. C. Promote the effective use of land; Staff Analysis: The Project is effectively developing the Site by providing single family residential lots that are within the density ranges required for the R-5 zoning district. D. Provide for adequate light and air; Staff Analysis: The Project will provide adequate light and air through the applicable setback and lot coverage development standards. E. Facilitate adequate provision for water, sewerage, storm drainage, parks and recreational areas, sites for schools and school grounds, and other public requirements; Staff Analysis: The Finding of Facts, and preceding analysis for Criteria A and B demonstrates the Project is providing adequate provisions for water supplies, sanitary wastes, drainage, roads, and other public requirements such as public health, safety, parks, and schools. F. Identify, preserve, and utilize native soils and/or vegetation for the purposes of reducing storm water discharges, promoting groundwater infiltration, and implementing the use of storm water low impact development techniques; 16 of 291 Staff Member: Gouk Date: October 1, 2019 Page 16 of 22 Staff Analysis: As is typical with single family residential subdivisions, the Site will be graded throughout to create building pads for the future homes, to construct the public and private roadways to meet the COADS, and to construct the stormwater facility (vault). The two areas that will be set aside as open space tracts that contain the wetlands, stream, and their buffers will not be disturbed with the exception of the wetland buffer enhancement and removal of trash / debris within the wetlands. Stormwater LID facilities will be utilized for Lots 14-19 with dispersion trenches located within / adjacent to the buffer for the wetland along the western portion of the site. G. Provide for proper ingress and egress; Staff Analysis: As demonstrated in the analysis for Criterion A, the Project will provide proper ingress and egress for each individual future home, and pedestrian connections to the public way. H. Provide for the expeditious review and approval of proposed land divisions which comply with this title, the Auburn zoning ordinance, other city plans, policies and land use controls, and Chapter 58.17 RCW; Staff Analysis: Staff has worked with the applicant to ensure a timely and comprehensive review of the Project. I. Adequately provide for the housing and commercial needs of the citizens of the state and city; Staff Analysis: The Project will eventually provide for 19 new single-family residences to serve future residents. J. Require uniform monumenting of land divisions and conveyance by accurate legal description; Staff Analysis: Upon final plat map review, the Project will be required to meet all applicable survey requirements. K. Implement the goals, objectives and policies of the Auburn Comprehensive Plan.” Staff Analysis: As analyzed in Criterion B, the Project successfully implements the Comprehensive Plan. Staff therefore finds the Project meets this criterion, as conditioned herein. E. Conformance of the proposed subdivision to the Auburn zoning ordinance and any other applicable planning or engineering standards and specifications as adopted by the city, or as modified and approved as part of a previously approved PUD; Staff Analysis: As analyzed in the ‘Preliminary Plat Findings’, above, the Project is able to meet applicable zoning and engineering standards, with the exception of the requested 17 of 291 Staff Member: Gouk Date: October 1, 2019 Page 17 of 22 engineering deviations which is discussed under the Engineering Deviation Findings and Conclusions, provided above and below, respectively. The placement of homes will be required to meet the zoning development standards for the R-5 zoning district to which the Project is vested (reference ‘Preliminary Plat Findings’ No. 4). Staff therefore finds that the Project is able to meet this criterion, as conditioned herein. F. The potential environmental impacts of the proposed subdivision are mitigated such that the preliminary plat will not have an unacceptable adverse effect upon the quality of the environment; Staff Analysis: There are two wetlands and a stream that are located on the Site. These will be set aside and permanently protected upon recordation of the Final Plat. The Project has been reviewed for conformance with applicable environmental regulations and is not expected to have any adverse environmental impacts. In addition, a downstream analysis for Mullens Slough was performed in conjunction with the Critical Areas Report and the stormwater system has been designed to avoid adverse impacts to both the environment and potential flooding offsite. The wetlands and stream will be protected during site development with temporary construction fencing and silt fences. Reference Exhibits 6 and 7. The grading plans proposed have been reviewed for conformance with City codes and regulations and per the Geotechnical Report (Exhibit 8) have been deemed suitable for development and erosion impacts can be adequately minimized or avoided. The Site is also located within Groundwater Protection Zone 4, which is the least stringent classification. With the utilization of Best Management Practices, it is anticipated that potential impacts to groundwater can be avoided. A DNS was issued on August 14, 2019 for this Project. Compliance with the recommended conditions of approval, City code, and engineering design standards will ensure that the Project will not have an adverse impact on the environment. During civil plan review process, the Project will be reviewed in accordance with applicable local, state, and federal standards to ensure no unacceptable adverse impacts to the environment occur. Staff therefore finds the Project meets this criterion, as conditioned herein. G. Adequate provisions are made so the preliminary plat will prevent or abate public nuisances; Staff Analysis: Adequate provisions are made, and will be made through the subsequent civil plan review process, so the proposed Project will prevent or abate public nuisances. As the Site is mainly undeveloped, there are no active code violation cases for the site, and no known public nuisances. 18 of 291 Staff Member: Gouk Date: October 1, 2019 Page 18 of 22 Staff therefore finds the Project meets this criterion, as conditioned herein. H. Lot configuration, street and utility layouts, and building envelopes shall be designed in a manner that identifies, preserves, and utilizes native soils and/or vegetation that are integrated into a low impact development facility, consistent with the city’s adopted storm water management manual. Staff Analysis: As analyzed in Criteria A, B, and D above, the Project has been designed such that it will be consistent with the City’s Engineering Design Standards and the Department of Ecology Stormwater Management Manual for Western Washington (SWMMWW) and Auburn Supplements. Staff therefore finds the Project meets this criterion, as conditioned herein. Engineering Deviation Conclusions The City Engineer has reviewed the requested Deviations and conditionally recommended approval of two of the three. Per Chapter 17.18 ACC ‘Modifications of Standards and Specifications’, the Hearing Examiner may approve a modification of any standard or specification established or referenced by Chapter 17.14 ACC ‘Improvement Requirements – Subdivisions’. Further, the City Engineer shall make a recommendation to the Hearing Examiner on any modifications requested from the City of Auburn Engineering Design Standards (COADS). This process is referred to as a “Deviation” per Section 1.06 of the COADS. Three Deviations were requested: 1. Utilize a stormwater detention vault in lieu of a pond (DEV19-0010, Exhibit 11). 2. Construct the private access road in Tract A to a slope greater than 8% (DEV19-0019, Exhibit 12). 3. Reduce the vehicle design speeds for the crest and sag curves for the proposed cul-de- sac (58th Ave. S) (DEV19-0032, Exhibit 13). The City Engineer has reviewed the Deviation requests and conditionally recommends approval for the stormwater vault, denied the request for Tract A, and recommends approval of the request for reduced vehicle design speeds to the Hearing Examiner; see Condition No. 19 under ‘Recommended Conditions of Approval’, below. Note that the private access road, Tract A, has since been redesigned to meet this Design Standard. STAFF RECOMMENDATION: Staff recommends approval of the Copper Ridge Preliminary Plat and two Engineering Deviation requests, subject to the information contained in this Staff Report, the attached exhibits, and the 20 recommended conditions of approval below. 19 of 291 Staff Member: Gouk Date: October 1, 2019 Page 19 of 22 RECOMMENDED CONDITIONS OF APPROVAL: 1. A final wetland buffer enhancement (mitigation) plan for Tracts C and E and the on-site wetlands and stream buffers shall be prepared and submitted with the civil (FAC) plans and consistent with Chapter 16.10 ACC. The wetlands and their associated 25-ft. buffers shall be placed in separate tracts on which development is prohibited, and protected by execution of an easement dedicated to the City. The easement shall grant the City access to on-site mitigation areas for the purposes of monitoring, maintaining, preserving, and enhancing the on-site wetlands and associated buffer areas, but not the obligation to do so. The location and limitations associated with the wetlands, stream and their buffers shall be shown on the face the final plat. The plan shall also ensure that areas within the open space tracts that are disturbed during the civil construction process will need to be restored; a planting / restoration plan shall be included with the FAC submittal. 2. A means of access for inspections and monitoring of the critical areas and their buffers within Tracts C and E (open space tracts) shall be designed and included with the FAC drawings, as reviewed and approved by the City. A note shall be included on the Final Plat indicating as such. 3. A note shall be placed on the Final Plat that the Homeowner’s Association, and it’s heirs and successors (HOA), shall be responsible for ownership, maintenance of the open space Tracts C and E and that there shall not be removal of any vegetation without prior City approvals. 4. Fencing shall be placed around the perimeter of the critical area buffers consistent with Chapter 16.10 ACC. Maintenance of the fencing shall be the responsibility of the HOA. 5. FAC approval will not be provided by the City of Auburn until approval for the construction drawings is obtained from Lakehaven Water & Sewer District for public water and public sewer. The Applicant shall provide approved plans to the City of Auburn once obtained 6. Prior to City approval of the civil plans under the FAC, the Applicant must provide documentation of submittal of an application to the Washington State Department of Ecology for a General Storm Permit, as required for all projects over 1 acre in size. 7. Fencing shall be provided around the perimeter of the stormwater vault, the location of which to be reviewed and determined during the FAC review and consistent with current City standards. 8. As part of the civil plans, a landscaping plan for the publicly dedicated stormwater Tract B shall be provided for city review and approval. The type and location of landscaping shall be coordinated with the location and type of fencing installed in the stormwater tract. The landscaping plan shall generally provide perimeter landscaping including shrubs designed to provide screening of the vault area and provide visual interest. The stormwater tract landscaping design must meet all applicable vehicle sight distance requirements. 20 of 291 Staff Member: Gouk Date: October 1, 2019 Page 20 of 22 9. A note shall be placed on the Final Plat indicating that the HOA shall be responsible to regularly maintain those portions of the stormwater Tract B outside of the fenced perimeter of the stormwater vault, as determined by the City Engineer. Additionally, the Covenants, Conditions, and Restrictions (CC&Rs) that are approved by the City at Final Plat application, and as recorded thereafter, shall establish the HOA’s responsibility for regular landscape maintenance. 10. The Final Plat shall indicate if the property owner(s) or the HOA is responsible for maintenance of the storm drainage system dispersion areas. Access to these areas for maintenance shall be shown / indicated on the FAC plans and contained on the Final Plat. 11. Low impact development (LID) stormwater facilities are proposed within portions of the Tracts C and E (open space tracts) including but not limited to dispersion trenches and associated flow areas. An Operation and Maintenance Manual shall be prepared by the Design Engineer, reviewed by the Wetland consultant, and utilized by the HOA. A Stormwater Maintenance and Easement / Agreement will be on the Final Plat to ensure maintenance of the LID facilities 12. An intersection control evaluation is required at the intersection of S 294th St. and 58th. Ave. S to determine the appropriate intersection traffic controls, such as but not limited to signage and markings. The intersection control evaluation shall consider traffic control options necessary to meet City requirements for safety in the right of way, and shall consider traffic movements from all directions of the intersection. The intersection control evaluation shall also include a horizontal sight distance analysis for all turning directions. The results of the intersection control evaluation shall be implemented by the review and approval of the civil plans. 13. Prior to City approval of the construction plans under the FAC, the plans shall show that appropriate portions of public streets shall be posted no parking due to its road width or presence of medians. Also, the cul-de-sac shall be posted “No Parking” around their entire perimeter. Posting shall be in accordance with ACC and City of Auburn Engineering Design Standards. 14. Any significant trees within the open space tracts should be retained to the fullest extent possible. In the event significant trees are removed a replanting plan, that provides for replacement at a ratio commensurate with the tree(s) diameter at breast height (DBH), should be developed as part of the civil plan review and approval. 15. If at the time of Final Plat application, the nature and location of the depicted occupation features remain unchanged and / or unresolved, then per RCW 58.17.255, a “survey discrepancy note” shall be placed on the face of the FINAL SHORT PLAT similar to the following example: SURVEY DISCREPANCY NOTE: EXISTING FENCES, RETAINING WALL AND ROCKERY HAVE BEEN SHOWN PURSUANT TO RCW 58.17.255 AND SHALL BE DISCLOSED IN THE TITLE REPORT PREPARED BY THE TITLE INSURER AND ISSUED AFTER THE FILING OF THIS 21 of 291 Staff Member: Gouk Date: October 1, 2019 Page 21 of 22 PLAT 16. Tracts A and D are private access and utility tracts and will be owned and maintained by the HOA. An ingress and egress easement, or other instrument as approved by the City, over Tract A must be granted to the City of Auburn, for the purpose of accessing Tract B (stormwater vault), providing emergency services, and pedestrian access to 59th Ave. SE. A note shall be placed on the Final Plat that the HOA is responsible for maintenance including associated retaining walls, walkways, signage, and other associated features. 17. The Applicant has requested a deviation to utilize a stormwater detention vault rather than an open stormwater pond. The City Engineer supports and recommends the Hearing Examiner approves the request with the following condition: The associated appurtenances and structures that are required to meet all applicable storm requirements for flow control and treatment shall be modified during final engineering design as needed to meet City requirements for maintenance and access. This includes modifications as needed to location, configuration, and depth of all structures and appurtenances associated with the detention vault. 18. The Applicant has requested a deviation to reduce the design speed for a crest curve from 30 MPH to 25 MPH and to reduce the sag curve design speed from 30 MPH to 15 MPH for the construction of 58th Ave. S. The City Engineer supports and recommends the Hearing Examiner approves the request. 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 ATTACHMENTS: Exhibit 1. Staff Report Exhibit 2. Vicinity Map Exhibit 3. Completed Preliminary Plat Application Forms, prepared by Soundbuilt Northwest, received July 31, 2018 Exhibit 4. Combined Notice of Application, DNS, and Notice of Public Hearing, and completed SEPA Checklist application Exhibit 5. Written Comment(s) Received and City Response(s) Exhibit 6. Preliminary Civil Plans, CORE Design, September 9, 2019 Exhibit 7. Critical Area Study & Preliminary Buffer Enhancement Plan, J.S. Jones and Associates, Inc., July 20, 2018, March 3, 2019, September 6, 2019 Exhibit 8. Geotechnical Report, Earth Solutions NW, LLC, September 12, 2018, February 18, 2019 Exhibit 9. Preliminary Stormwater Report, CORE Design, July 30, 2019 Exhibit 10. School Walkway Analysis, CORE Design, July 16, 2018 Exhibit 11. DEV19-0010 Engineering Deviation Request & COA Recommend Approval Letter, CORE Design, February 22, 2018 / July 18, 2019 Exhibit 12. DEV19-0019 Engineering Deviation Request & COA Denial Letter, CORE Design, April 24, 2019 / May 30, 2019 Exhibit 13. DEV19-0032 Engineering Deviation Request & COA Recommended Approval Letter, CORE Design, September 27, 2019 / September 30, 2019 22 of 291 Staff Member: Gouk Date: October 1, 2019 Page 22 of 22 Exhibit 14. Water and Sewer Availability Certificate from Lakehaven, May 10, 2018 Prepared by Thaniel Gouk, Senior Planner / Alexandria Teague, Planner II, Reviewed by Jeff Dixon, Planning Services Manager 23 of 291 Map data © OpenStreetMap contributors, CC-BY-SA Date: 10/2/2019 Notes: tgouk ±The information included on this map has been compiled by King County staff from a variety of sources and issubject to change without notice. King County makes no representations or warranties, express or implied,as to accuracy, completeness, timeliness, or rights to the use of such information. This document is not intendedfor use as a survey product. King County shall not be liable for any general, special, indirect, incidental, orconsequential damages including, but not limited to, lost revenues or lost profits resulting from the use or misuseof the information contained on this map. Any sale of this map or information on this map is prohibited except bywritten permission of King County. Vicinity Map Project Site EXHIBIT 2 24 of 291 EXHIBIT 3 25 of 291 EXHIBIT 3 26 of 291 EXHIBIT 3 27 of 291 EXHIBIT 3 28 of 291 EXHIBIT 3 29 of 291 EXHIBIT 4 30 of 291 EXHIBIT 4 31 of 291 EXHIBIT 4 32 of 291 EXHIBIT 4 33 of 291 EXHIBIT 4 34 of 291 EXHIBIT 4 35 of 291 EXHIBIT 4 36 of 291 EXHIBIT 4 37 of 291 EXHIBIT 4 38 of 291 EXHIBIT 4 39 of 291 EXHIBIT 4 40 of 291 EXHIBIT 4 41 of 291 EXHIBIT 4 42 of 291 EXHIBIT 4 43 of 291 EXHIBIT 4 44 of 291 EXHIBIT 4 45 of 291 1 Thaniel Gouk Sent:Thursday, August 29, 2019 8:34 AM To:2065792968@mms.att.net Subject:RE: SEP18-0017/PLT18-0004 Good morning Mary Jo. Hopefully you received my voicemail the other day when I returned your call. I'm sorry our hours didn't work out that we could speak in person. I and the City appreciate your comments and concerns and I will be sure to point them out and include them in the staff report to the City's Hearing Examiner. If your schedule allows it I would also like to invite you to provide your comments in person at the public hearing on October 16th. In response to your comments, I understand your concerns and in case you weren't able to read through all the documents the applicant provided, they are setting aside the areas that contain the stream and wetlands and those areas will be permanently protected. I will be sure to include you if any future information is presented; at this time there will not likely be anything until after the public hearing. Thanks, Thaniel Gouk, Auburn Planning. (note, I see you sent this from your phone so I'm deleting your initial message so hopefully this comes through clear) -----Original Message----- From: 2065792968@mms.att.net <2065792968@mms.att.net> Sent: Wednesday, August 28, 2019 8:42 PM To: Planning-1 <Planning@auburnwa.gov> Subject: CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments SEP18-0017/PLT18-0004 I do not understand how the lead agency, the City of Auburn, has determined that it does not have probable significant adverse impact on the environment. I believe it does. I live on 294th and 58th street where you will be making an entrance to this 19 home project across from my home. There are wetlands and a stream that runs through here. There are also owls, doves, and an eagle that reside back there. Raccoons and rabbits also live there. Birds and hummingbirds etc. Many fruit trees are also there. Making 294th and 58th the entrance to this neighborhood will also be a hardship, considering there is already a lot of traffic through here. With 19 more homes it will be quite busy and more like an asphalt parking lot with cramped houses and much more traffic. I moved here because of the beauty, animals and wildlife, which gets harder to find these days, and nowhere for them to go but out of here. To me this is an environmental impact and I cannot understand that you think it is not. I don't feel that I will be the only person feeling this way. I would like to be included in any upcoming information regarding this matter. Sincerely, Mary Jo Tarbuck 253-941-3773 EXHIBIT 5 46 of 291 From: Thaniel Gouk Sent: Monday, August 19, 2019 8:28 AM To: 'Mary Beth Dahl' Subject: RE: Notice of proposed land use action App. #SEP18-0017 Mary Beth – your comment has been received and I will be sure to include it in the Staff Report to the Hearing Examiner. Thank you, Thaniel Gouk – Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov 253.804.5031 | tgouk@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 Customer Service Survey Application Forms Zoning Maps From: Mary Beth Dahl <mbeth.dahl@gmail.com> Sent: Friday, August 16, 2019 4:33 PM To: Planning-1 <Planning@auburnwa.gov> Subject: Notice of proposed land use action App. #SEP18-0017 CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments I want to register my strong objection to this proposed land use across the street from my house. The forests and greenbelts are disappearing from Auburn West Hill and enough is enough! We're losing animal and bird habitat and turning into Levittown. Please stop this latest attempt. Mary Beth Dahl 29417 58th Ave.S. Auburn, WA 98001 EXHIBIT 5 47 of 291 EXHIBIT 5 48 of 291 From: Karen Walter <KWalter@muckleshoot.nsn.us> Sent: Wednesday, August 28, 2019 11:12 AM To: Thaniel Gouk Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance Attachments: WDFW salmonscape map for Mullen Slough and tributaries.pdf; WDFW barrier map for Mullens Slough.pdf; Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban watersheds.pdf; Spromberg_et_al-2016 Coho salmon spawner mortality in western US urban biofiltration prevents lethal stormwater impacts.pdf CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Thaniel, We have reviewed the SEPA documents and other available information for the proposed West Hill 19- lot plat at 29255 and 29242 59th Ave S in Auburn, We offer the following comments in the interest of protecting and restoring the Tribe’s treaty-protected fisheries resources: 1. Stream classification The checklist may be incorrect regarding the stream classification of Mullens Slough tributaries found both on and adjacent to the project site. According to WDFW’s Salmonscape map, there is documented coho presence throughout the entire stream. (See attached map). This information was neither identified nor considered in the project materials. Further, there are no documented natural or artificial barriers currently identified in Mullen Slough or its tributaries downstream of the site. WDFW’s information may not be fully complete. If Auburn has data to suggest otherwise, we request a copy of this information. The culvert on 59th Avenue that conveys the Mullens Slough tributary may be a fish passage barrier based on its size (24”) versus the stream bankfull of 2-4 feet in width. The slope of culvert is unknown but it, too, may a factor in the barrier condition of this culvert. Auburn needs to treat this tributary of Mullens Slough as a fish-bearing water in absence of information otherwise. If there is data to suggest otherwise, we request a copy and the opportunity to review it and provide further comments as needed. 2. Project impacts The project currently does not comply with mitigation sequencing requirements. The Critical Areas Report starts with the proposal to reduce wetland (and arguably stream buffers) without any explanation as to purpose and need and how mitigation sequencing was met which is EXHIBIT 5 49 of 291 contrary to State SEPA requirements. There is no analysis or demonstration that this project needs to impact the existing stream and wetland buffers as proposed. Avoidance is the first step in mitigation sequencing. There is no information about how this project is minimizing its impacts. Finally, there is no analysis to demonstrate that the full impacts of the proposed buffer reductions affects stream and wetland functions (including a tree inventory to determine riparian functional losses). Finally, there is no analysis to demonstrate that the proposed mitigation adequately offsets these impacts and ensures a no net loss of wetland or stream functions. Also, with respect to the proposed stormwater treatment method, the project should be providing enhanced treatment since this project will discharge its stormwater to Mullens Slough tributaries that have known salmon use. Salmon can be adversely affected by oils and heavy metals in stormwater; therefore, the project needs to maximize treatment to minimize the project’s potential impacts from stormwater discharges. Some of the available scientific data and literature is in the attached papers. There is substantial more information on this topic available online. We appreciate the opportunity to review this proposal and look forward to the City/applicants’ written responses to these concerns. We may have further comments subsequently. Thank you, Karen Walter Watersheds and Land Use Team Leader Muckleshoot Indian Tribe Fisheries Division Habitat Program 39015-A 172nd Ave SE Auburn, WA 98092 253-876-3116 From: Thaniel Gouk [mailto:tgouk@auburnwa.gov] Sent: Wednesday, August 14, 2019 11:53 AM To: 'cblansfield@auburn.wednet.edu'; 'brian.davis@cityoffederalway.com'; 'paan461@ecy.wa.gov'; 'sepaunit@ecy.wa.gov'; 'MARI461@ECY.WA.GOV'; 'sepacenter@dnr.wa.gov'; 'jim.chan@kingcounty.gov'; 'hubenbj@dshs.wa.gov'; 'tosborne@lakehaven.org'; 'kbush@mbaks.com'; Karen Walter; 'shirlee.tan@kingcounty.gov'; 'cmoore@fwps.org'; 'tim@futurewise.org'; 'Valerie.Garza@kingcounty.gov'; 'Planning@KentWA.gov'; 'josh.baldi@kingcounty.gov'; 'Steve.Bleifuhs@kingcounty.gov'; 'beth.humphreys@kingcounty.gov'; 'laila.mcclinton@kingcounty.gov'; 'pazookr@wsdot.wa.gov'; 'maint.roads@kingcounty.gov'; 'jgreene@kingcounty.gov'; Jeffrey Watson; Krongthip Sangkapreecha; Rob Otsea; Laura Murphy; 'sepa@dahp.wa.gov'; 'gretchen.kaehler@dahp.wa.gov'; 'jeff.payne@pse.com'; 'James.H.Carsner@usace.army.mil'; 'SEPA@pscleanair.org'; 'perry.weinberg@soundtransit.org'; 'rob.ryan@wa.usda.gov'; Karen Stewart VRFA; 'reviewteam@commerce.wa.gov'; 'Larry.Fisher@dfw.wa.gov'; 'mindy@wecprotects.org'; 'SEPA.reviewteam@doh.wa.gov' Cc: Planning-1 Subject: SEP18-0017 - Soundbuilt Homes 19-Lot Preliminary Plat EXHIBIT 5 50 of 291 Please see the attached SEPA DNS and associated SEPA Checklist. Please submit any comments by August 29, 2019. More information is available on the City’s website at www.auburnwa.gov/landuse. Thanks, Thaniel Gouk – Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov 253.804.5031 | tgouk@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 Customer Service Survey Application Forms Zoning Maps This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. EXHIBIT 5 51 of 291 Mullens Slough tribs Sources: Esri, HERE, Garmin, Intermap, increment P Corp., GEBCO, USGS,FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, EsriJapan, METI, Esri China (Hong Kong), (c) OpenStreetMap contributors, andthe GIS User CommunityWDFW Coho Streams Documented Presence Documented Spawning Documented Rearing Modeled Presence Presumed Presence Potential: Blocked Documented Historic Presence Transported Presence Transported Spawning Transported Rearing Documented-Artificial, Presence Documented-Artificial, Spawning Documented-Artificial, Rearing August 28, 2019 0 0.6 1.20.3 mi 0 1 20.5 km 1:36,112 EXHIBIT 5 52 of 291 Coho salmon spawner mortality in western US urban watersheds: bioinﬁltration prevents lethal storm water impacts Julann A. Spromberg 1, David H. Baldwin 2, Steven E. Damm 3, Jenifer K. McIntyre 4, Michael Huff 5, Catherine A. Sloan 2, Bernadita F. Anulacion 2, Jay W. Davis 3 and Nathaniel L. Scholz 2* 1Ocean Associates, Under Contract to Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112, USA; 2Environmental and Fisheries Science Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. E., Seattle, WA 98112, USA;3U.S. Fish and Wildlife Service, Washington Fish and Wildlife Ofﬁce, 510 Desmond Dr. S.E., Lacey, WA 98503, USA;4Puyallup Research and Extension Center, Washington State University, 2606 W. Pioneer Ave., Puyallup, WA 98371, USA; and 5Suquamish Tribe, PO Box 498, 18490, Suquamish Way, Suquamish, WA 98392, USA Summary 1.Adult coho salmon Oncorhynchus kisutch return each autumn to freshwater spawning habitats throughout western North America. The migration coincides with increasing seasonal rainfall, which in turn increases storm water run-off, particularly in urban watersheds with extensive impervious land cover. Previous ﬁeld assessments in urban stream networks have shown that adult coho are dying prematurely at high rates (>50%). Despite signiﬁcant man- agement concerns for the long-term conservation of threatened wild coho populations, a cau- sal role for toxic run-off in the mortality syndrome has not been demonstrated. 2.We exposed otherwise healthy coho spawners to: (i) artiﬁcial storm water containing mix- tures of metals and petroleum hydrocarbons, at or above concentrations previously measured in urban run-off; (ii) undiluted storm water collected from a high trafﬁc volume urban arterial road (i.e. highway run-off); and (iii) highway run-off that was ﬁrst pre-treated via bioinﬁltra- tion through experimental soil columns to remove pollutants. 3.We ﬁnd that mixtures of metals and petroleum hydrocarbons –conventional toxic con- stituents in urban storm water –are not sufﬁcient to cause the spawner mortality syndrome. By contrast, untreated highway run-off collected during nine distinct storm events was univer- sally lethal to adult coho relative to unexposed controls. Lastly, the mortality syndrome was prevented when highway run-off was pretreated by soil inﬁltration, a conventional green storm water infrastructure technology. 4.Our results are the ﬁrst direct evidence that: (i) toxic run-off is killing adult coho in urban watersheds, and (ii) inexpensive mitigation measures can improve water quality and promote salmon survival. 5.Synthesis and applications. Coho salmon, an iconic species with exceptional economic and cultural signiﬁcance, are an ecological sentinel for the harmful effects of untreated urban run- off. Wild coho populations cannot withstand the high rates of mortality that are now regularly occurring in urban spawning habitats. Green storm water infrastructure or similar pollution prevention methods should be incorporated to the maximal extent practicable, at the watershed scale, for all future development and redevelopment projects, particularly those involving transportation infrastructure. Key-words:habitat restoration, non-point source pollution, Paciﬁc salmon, run-off, storm water, urban ecology, urban streams *Correspondence author. E-mail: nathaniel.scholz@noaa.gov ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. Journal of Applied Ecology 2016,53,398–407 doi: 10.1111/1365-2664.12534 EXHIBIT 5 53 of 291 Introduction In recent decades, non-point source run-off has become the leading pollution threat to aquatic habitats in the USA and similarly developed countries. In highly built watersheds, the transport of toxic chemical contaminants via storm water contributes to the well documented ‘urban stream syndrome’, as evidenced by various indica- tors of biological and ecological degradation (Walsh et al. 2005). These include declines in species abundance, species diversity and the proliferation of non-native, pollution- tolerant taxa. Nevertheless, ﬁeld assessments in urban watersheds rarely report ﬁsh kills or similar acute mortality events for aquatic life. A notable exception is the recurring die-off of adult coho salmon that return from the ocean to spawn each year in large metropolitan areas of northern Califor- nia, western Oregon and Washington in the USA, and southern British Columbia in Canada. The coho mortality phenomenon has been studied most extensively in lowland streams of the greater Seattle area of Puget Sound. Coho begin the freshwater phase of their spawning migration with the onset of autumn rainfall. Typically within days of arriving at stream reaches suitable for spawning, affected ﬁsh become stricken with symptoms that progress from a loss of orientation (surface swimming) to a loss of equilibrium and death on a time-scale of a few hours (Videos S1 and S2, Supporting information; Scholz et al. 2011). Year-to-year mortality rates within and across urban watersheds are typically high (~50–90%), as mea- sured by the proportion of unspawned females for an entire annual run (Scholz et al.2011). As might be expected, initial modelling indicates that such high mortality rates at the critical spawner life stages pose a signiﬁcant extinction risk for wild coho populations (Spromberg & Scholz 2011). Coho distinct population seg- ments, or evolutionarily signiﬁcant units (ESUs; Waples 1991), are comprised of metapopulations that span large river basins with varying degrees of urban and suburban land use (e.g. Pess et al.2002; Bilby & Mollot 2008). This population structure and the highly migratory life histories of salmonids have generally constrained ecotoxicological studies (Ross et al.2013). Nevertheless, if urban run-off is killing adult coho, ongoing regional development pressures may present an important obstacle to the recovery of coho ESUs, including those designated as threated (Lower Columbia River) or a species of concern (Puget Sound) under the US Endangered Species Act. To date, the evidence linking urban storm water run-off and coho spawner mortality has been indirect. The uni- form nature of the symptoms, over many years and across many streams, is consistent with a common and prevalent form of toxicity. A forensic investigation spanning nearly a decade ruled out several other potential causes, includ- ing conventional water quality parameters (e.g. dissolved oxygen, temperature), habitat availability, poor spawner condition and disease (Scholz et al.2011). Moreover, an initial geospatial land cover analysis found a signiﬁcant positive association between the severity of the coho die- off phenomenon and the extent of impervious surface within a watershed (Feist et al.2011). The aim of the present study was to explore the connec- tion between water quality and coho mortality more directly by experimentally exposing freshwater-phase spawners to both artiﬁcial and actual highway run-off. Although urban storm water is chemically complex, ﬁeld collected samples consistently contain motor vehicle- derived mixtures of metals and polycyclic aromatic hydro- carbons (PAHs), many of which are toxic to salmon at other life stages (e.g. copper, McIntyre et al.2012; Sandahl et al.2007; PAHs, Meador et al.2006; Heintz et al.2000). If the mortality syndrome could be repro- duced with an environmentally realistic mixture of metals and PAHs, it would then be possible to identify the causal agents by removing different components of the mixture. To account for the possibility that some other contami- nant(s) may be causal, we also exposed adult coho to storm water collected from a dense urban arterial road (i.e. highway run-off). Lastly, we exposed adult coho to highway run-off which was pre-treated with a conven- tional green storm water infrastructure (GSI) technology (bioinﬁltration through soil columns) to remove pollu- tants, with the aim of lessening or eliminating any overtly harmful impacts of unmitigated storm water. Materials and methods ANIMALS Adult coho salmon were collected at the Suquamish Tribe’s Gro- vers Creek Hatchery near Poulsbo, Washington. Hatchery coho are an appropriate surrogate for wild coho given that ﬁeld obser- vations have documented the mortality syndrome in spawners of both wild and hatchery origins (Scholz et al.2011). At Grovers Creek, returning coho migrate <4 km in freshwater from Miller Bay in Puget Sound to a hatchery pond via a ﬁsh ladder. The pond was seined on Monday, Wednesday and Friday of each week, and thus the ﬁsh were in the pond for a maximum of 72 h prior to capture. The coho were strays from a net-pen operation designed to provide a terminal ﬁshery to the south of Miller Bay. When available, females were used for the controlled storm water exposures. For trials with an insufﬁcient number of females, males were also included, as the urban mortality syndrome affects males and females alike (Scholz et al.2011). Only ﬁsh exhibiting normal behaviour and with no obvious signs of trauma, disease or poor condition were included. One set of exposures was con- ducted on a given day. Each individual coho spawner was placed in a holding tube con- structed of PVC, of either 15 2 9 762 cm (diameter 9 length) or 203 9 1067 cm with 1 1-cm-thick polyethylene gates ﬁtted into slots at either end. Ventilation was provided by six 25-cm-diameter holes on either side of the anterior (head) end of each tube and ﬁve 175-cm-diameter holes in each gate. A ventilation hose attached to a pump (for 2011–12, a Flotec Tempest 1/6 HP, 45m3 h 1 (Flotec Water, Delavan, WI, USA); for 2013–14, a Lifegard Aquatics Quiet One 3000, 31m3 h 1 (Lifegard Aquatics, Cerritos, CA, ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 399 EXHIBIT 5 54 of 291 USA)) submerged in the polyethylene tank supplied a minimum of 4 L min 1 ﬂow through the forward gate and over each ﬁsh in an anterior–posterior direction. For each trial, four separate coho holding tubes were placed in a large polyethylene tank containing 440 L of clean well water, artiﬁcial storm water, highway run-off, or run-off pretreated with soil inﬁltration. Adult coho were exposed for 4–48 h depending on the treatment (see below). Aeration was provided with air stones attached to an air pump (Coralife 05146 Model SL-38 Super Luft Air Pump, Central Aquatics-Coralife, Franklin, WI, USA). Exposure waters were maintained at temperatures below 14 °C by ﬂow-through (2011) and Aqua Logic Cyclone Drop- In Titanium Chillers (2012). Smaller ventilation pumps that pro- duced less heat were used in 2013–14, and thus, chillers were not needed. EXPOSURES TO ARTIFICIAL STORM WATER In the autumn of 2011, returning adult coho were exposed to artiﬁcial storm water containing mixtures of PAHs and metals. The mixtures were comprised of individual compounds at concen- trations at or above those measured during autumn storm events in Seattle-area urban streams (Seattle Public Utilities 2007), or at levels representative of urban storm water run-off more generally (Stein, Tiefenthaler & Schiff 2006; Gobel, Dierkes & Coldewey 2007; Tiefenthaler, Stein & Schiff 2008). The PAH proﬁle of urban run-off is compositionally similar to that of crude oil, par- ticularly for toxic three- and four-ring compounds (McIntyre et al.2014). The exception is a lack of dissolved pyrene and ﬂuo- ranthene in crude oil (Incardona et al.2009). Thus, the PAH por- tion of the mixture was generated from a water-accommodated fraction (WAF) of Alaska North Slope crude oil, to which pyro- genic pyrene and ﬂuoranthene were added (Table S1). The WAFs were prepared in a 3-speed commercial blender with a 38-L stainless steel container (Waring CB15; Waring Commercial, Tor- rington, CT, USA), following a protocol developed to yield ﬁne oil droplets and bioavailable PAHs in the dissolved phase (Incardona et al.2013). In brief, the stainless steel container was cleaned with acetone and dichloromethane, the rubber lid was lined with dichloromethane-rinsed heavy-duty aluminium foil, and the container was ﬁlled with 1 L of deionized water. The vol- ume of crude oil added to the WAF (1 mL) was intended to pro- duce a ﬁnal maximum phenanthrene exposure concentration of 0384 lgL 1 (Stein, Tiefenthaler & Schiff 2006). Pyrene and ﬂuo- ranthene were then added to coequal ﬁnal target exposure con- centrations of 0584 lgL 1. Water and oil were blended for 30 s on the lowest speed four times. The oil–water mixture was then poured into a 1-L separatory funnel and allowed to sit for 1 h. With care to leave the surface slick undisturbed, 7893 mL at the bottom were then drawn off and added to the exposure chamber. The metals fraction of the PAHs/metals mixture consisted of cadmium, nickel, lead, copper and zinc (anhydrous CdCl2, NiCl2, PbCl2,CuCl2 and ZnCl2; Sigma-Aldrich, St. Louis, MO, USA, >98% purity) added to clean well water at nominal concentra- tions (Table S1) that were in the upper range of metal detections in urban streams (Stein, Tiefenthaler & Schiff 2006; Gobel, Dierkes & Coldewey 2007; Seattle Public Utilities 2007; Tiefen- thaler, Stein & Schiff 2008). Moreover, the concentrations of met- als in urban run-off are transiently elevated during the ﬁrst ﬂush interval (Kayhanian et al.2012). To capture this exposure scenar- io, experiments in the autumn of 2012 used relatively higher nominal concentrations of metals only (Table S1). Temperature and dissolved oxygen were monitored and maintained at physio- logical ranges for adult salmon, and water samples were collected for analytical veriﬁcation of exposure concentrations. EXPOSURES TO HIGHWAY RUN-OFF Storm water was collected from the downspouts of an elevated urban principal arterial road in Seattle, WA. The downspouts receive run-off from the on-ramp to a four-lane (70 m wide) highway over which approximately 60 000 motor vehicles travel each day (WA DOT 2013a). The highway, paved with Portland cement concrete (WA DOT 2013b), is a conventional urban impervious surface. All of the ﬂow to the downspouts originated from precipitation falling on the active arterial road. The captured run-off was transported to the hatchery facility in either covered glass carboys or in a stainless steel tank. The holding interval prior to exposures varied with the timing and intensity of autumn storm events, but did not exceed 72 h. While some collec- tions took place after an extended antecedent dry interval and therefore included the ﬁrst ﬂush for a given storm, others spanned periods of intermittent rainfall. Daily and cumulative rainfall for each autumn season is shown in Fig. 1, with each storm water col- lection interval superimposed (solid rectangular boxes). Collected run-off was used for one exposure only. Temperature, pH and dis- solved oxygen were measured at the outset of each exposure, and water samples were collected for chemical analyses to quantify con- centrations of metals and PAHs (2012–13 but not 2014 storms). After exposures, the run-off was transported to a Kitsap County Wastewater Pump Station for disposal. EXPOSURES TO FILTERED RUN-OFF In the autumn of 2013, four 200-L bioretention columns were con- structed and plumbed with outﬂow drains following conventional guidelines for green storm water infrastructure (WA DOE 2012). The ﬁltration columns were composed of a 305-cm drainage layer of gravel aggregate overlain by 61 cm of bioretention soil media (60% sand: 40% compost) and topped with 5 cm of mulched bark. In the autumn of 2014, the bioretention columns were emptied and fresh media installed. In each year, the bioretention media were conditioned by passing seven pore volumes (660 L) of clean well water from the hatchery facility through each column at a rate of 2 L min 1: equivalent to 2 months of summer rainfall on a con- tributing area 20 times the size of the treatment area. Urban high- way run-off was collected as described above, and the homogenized volume was evenly divided to ﬂow through one of the four bioretention columns at a rate of 2 L min 1, with the out- ﬂows from the four columns recombined into a single post-treat- ment exposure volume. Adult coho spawners were exposed to either untreated urban storm water or the same run-off post- ﬁltration for 4–24 h. Water quality was measured, and samples were collected for chemical analyses as described above. OBSERVATIONS OF SYMPTOMATIC FISH Hallmark characteristics of the adult coho spawner mortality syn- drome include a progression from lethargy to a loss of orienta- tion, a loss of equilibrium, followed by death (Scholz et al.2011). Individual ﬁsh were examined for these symptoms during and after each exposure. Fish were moved from the large exposure ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 400 J. A. Spromberg et al. EXHIBIT 5 55 of 291 tank and released from their holding tubes into an observation tank containing clean well water at a minimum depth of 50 cm. Swimming ability and evasiveness (responses to light and gentle prodding) were recorded over a 1- to 3-min observation interval. For the trials using artiﬁcial storm water, symptomology was assessed at 24 h and then again at the end of the exposure. Coho exposed to highway run-off were visually examined at 2, 4 and 24 h. Live ﬁsh at 2 and 4 h were returned to their holding tubes and exposure chambers for the remainder of the trial. WATER QUALITY ANALYSES Conventional water quality parameters, including pH, dissolved oxygen, alkalinity, total suspended solids, N-ammonia, nutrients and organic carbon, were measured for selected trails using stan- dard instrumentation or by outside laboratories using US EPA- approved methods (Analytical Resources Inc., Tukwila, WA, USA or Am Test Inc., Kirkland, WA, USA). Total and dissolved concentrations of cadmium, copper, nickel, lead and zinc were determined by inductively coupled plasma mass spectrometry (ICP-MS) by Frontier Global Sciences (Bothell, WA, USA; EPA method 1638) or Am Test Inc. (EPA method 200.8). Brieﬂy, sam- ples were preserved in 1% (v/v) nitric acid (total metals) or passed through a 045-lm ﬁlter (dissolved metals) and then oven- digested prior to analysis by ICP-MS. Duplicate samples and lab- oratory blanks were included to ensure quality control. Selected water samples for PAH determinations were preserved with 10% dichloromethane and stored at 4 °C in amber glass bottles until analysis at the NOAA Northwest Fisheries Science Center by gas chromatography/mass spectrometry (GC-MS) with additional selected ion monitoring for alkyl-PAHs (Sloan et al.2014). TISSUE SAMPLING AND ANALYSES At the conclusion of each exposure, ﬁsh length, weight, reproduc- tive status and origin (i.e. hatchery or wild spawned) were assessed. To conﬁrm the bioavailability of PAHs in exposure waters, bile was screened for PAH metabolites in a subset of 2011 and 2012 trials with both artiﬁcial storm water and highway run-off. Fish were killed, and bile was collected from the gall bladder and stored in amber glass vials at 20 °C until analysis for PAH metabolites using high-performance liquid chromatogra- phy with ﬂuorescence detection (Krahn et al.1986; da Silva et al. 2006). The concentrations of ﬂuorescent PAH metabolites in bile are determined using naphthalene (NPH), phenanthrene (PHN) and benzo[a]pyrene (BaP) as external standards and converting the relative ﬂuorescence response of bile to NPH, PHN and BaP equivalents, and reported as ng g 1 bile or ng mg 1 biliary pro- tein. Coho gills were sampled to conﬁrm uptake of metals in selected 2011 and 2012 artiﬁcial and collected storm water exposures. Tis- sues were excised with Teﬂon or titanium scissors and plastic for- ceps, placed in plastic Whirl-paks, and stored at 80 °C. Metals analyses were determined by inductively coupled mass spec- troscopy (ICP-MS) at the Trace Elements Research Laboratory (TERL; College Station, TX, USA) using standard methods (TERL Method Codes 001, 006). Brieﬂy, gill tissues were wet digested with nitric acid, freeze-dried, and homogenized by ball- milling in plastic containers. Samples were ionized in high- temperature argon plasma, and positively charged ions were sepa- rated on the basis of their mass : charge ratios by a quadrupole mass spectrometer. Student’s t-tests assessed differences in the tis- sue concentrations between exposures and their respective paired control. Results ADULT COHO RESPONSES ACROSS TREATMENTS Coho spawners exposed for 24 h to mixtures of PAHs and metals at concentrations slightly higher than those previously measured in urban run-off were asymptomatic Fig. 1.The presence or absence of the pre- spawn mortality syndrome in adult coho salmon exposed to unﬁltered highway run- off (E) or clean well water (C). Paired exposures spanned three consecutive autumn spawning seasons, 2012–14. Shown in each panel are daily rainfall (shaded bars), cumulative rainfall (dotted lines), highway run-off collection intervals for each separate exposure event (black rectangles) and the presence or absence of symptomatic (or dead) ﬁsh in each individ- ual treatment (4–24 h duration; see Mate- rials and methods). Symptoms included lethargy, loss of orientation or loss of equilibrium. ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 401 EXHIBIT 5 56 of 291 –that is behaviourally indistinguishable from controls exposed to clean well water (Table 1). Although there was some mortality across the four independent trials (n =4 of 30 ﬁsh total), this was not signiﬁcantly different by treatment (Fisher exact tests, two-tailed,P ≥0 21) and was therefore apparently attributable to handling stress. Extending the exposures to 48 h did not increase the inci- dence of mortality or symptomology (n =4 of 22 ﬁsh total, two control and two exposed). Increasing the con- centrations of metals ﬁvefold or 10-fold in metal-only mixtures was also insufﬁcient to elicit the symptoms of the pre-spawn mortality syndrome (Table 2). As with the PAHs/metals mixture, there was a small but insigniﬁcant amount of mortality across treatments (n =2 of 38 ﬁsh; Fisher exact tests, two-tailed,P =1). Although the artiﬁcial storm water preparations were designed to have a similar composition to highway run- off for many PAHs and metals, the effects on coho spawners were very different. Whereas the artiﬁcial mix- tures did not elicit the distress characteristic of the mortal- ity syndrome, coho exposed to the unﬁltered highway run-off rapidly became symptomatic. For every discrete rainfall collection interval (n =9; 2012–2014), all of the exposed ﬁsh were either symptomatic or dead within 4 h (Fig. 1, Table 3). Those that survived the initial 4-h expo- sure were dead by 24 h. All of the paired control coho in clean well water survived, showing no behavioural symp- toms at 4 or 24 h (Fig. 1, Table 3). Each exposure showed a statistically signiﬁcant difference in mortality (Fisher exact tests, two-tailed,P =0 006). Examples of asymptomatic control ﬁsh and symptomatic, run-off- exposed spawners are shown in Video S3. For the purpose of comparing symptoms, digital movies of affected coho in Seattle-area urban watersheds are shown in Videos S1 and S2. Thus, despite the event-to-event variation in rain- fall duration and intensity, and a corresponding variation in water chemistry (conventionals, metals and PAHs, Tables S2, S3 and S5), urban run-off was 100% lethal to otherwise healthy adult coho salmon. The contribution of handling stress was evidently minimal, as the survival rate for controls across treatments in 2012–2014 was 100%. The constructed bioretention columns effectively treated the highway run-off in terms of both toxic chemical expo- sure and salmon spawner survival. Although the focal (measured) contaminants were not completely removed by inﬁltration, the overall improvement in water quality was sufﬁcient to completely prevent the lethal effects and sub- lethal symptomology caused by untreated storm water. All of the adult coho exposed to ﬁltered run-off survived and showed no behavioural symptoms at either 4 or 24 h (100% survival,n =20; Table 3; Video S3). Thus, urban storm water contains an as-yet unidentiﬁed chemical com- ponent(s) that, while lethal to salmon spawners, can be removed using inexpensive bioinﬁltration. MEASURED LEVELS OF METALS, PAHS AND CONVENTIONAL WATER QUALITY PARAMETERS ACROSS TREATMENTS The chemical properties of highway run-off were evaluated for the six distinct collection events in the autumn of 2012 Table 1.Adult coho salmon spawner mortality following a 24-h exposure to either clean well water (unexposed) or a mixture of polycyclic aromatic hydrocarbons (PAHs) and metals. Shown in parentheses are the numbers of symptomatic or dead ﬁsh as a proportion of the total numbers of spawners in each exposure. The PAH/metal exposures were based on measured levels in urban creeks during storm events (see Materials and methods). Relative to environmental samples, the artiﬁcial mixture con- tained higher concentrations of both total PAHs and metals. Each exposure was conducted on a separate day Exposure (h) Mortality Unexposed PAHs/Metals mixture 24 25% (1/4) 0% (0/4) 24 33% (1/3) 0% (0/3) 24 0% (0/4) 50% (2/4) 24 0% (0/4) 0% (0/4) Table 2.Exposures to relatively high levels of metals in artiﬁcial mixtures are not sufﬁcient to elicit the coho spawner mortality syndrome. Similar to unexposed controls, nearly all of the adults survived exposures to mixtures of metals (Cd, Cu, Pb, Ni, Zn) that were ﬁvefold (Low) or 10-fold (High) higher than measured concentrations in urban creeks where coho mortality syndrome was observed. Shown in parentheses are the numbers of symp- tomatic or dead ﬁsh as a proportion of the total numbers of spawners in each exposure. Each exposure was conducted on a separate day Exposure (h) Mortality Unexposed Low metals High metals 24 0% (0/4) 0% (0/4) 24 0% (0/4) 0% (0/3) 24 0% (0/4) 0% (0/4) 24 25% (1/4) 25% (1/4) 24 0% (0/3) 0% (0/4) Table 3.Proportion of adult coho displaying the spawner mortal- ity syndrome after placement in clean well water (unexposed) or highway run-off that was either unﬁltered or ﬁltered through an experimental soil bioretention system (during 2013 and 2014). Shown in parentheses are the numbers of symptomatic or dead ﬁsh as a fraction of the total number of coho in each treatment. Each exposure was conducted on a separate day Exposure (h) Mortality Unexposed Unﬁltered Filtered 4 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) 24 0% (0/4) 100% (4/4) 0% (0/4) ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 402 J. A. Spromberg et al. EXHIBIT 5 57 of 291 and 2013. As expected, conventional water quality parameters varied across storm water collections, as did concentrations of PAHs and metals. The analytical results are shown in Tables S2, S3 and S5. As expected, suspended solids (TSS: 23–220 mg L 1) and organic matter (DOC: 8–92 mg L 1) were elevated in urban run-off relative to control water (TSS <1 1mgL 1, DOC <1 8mgL 1). In contrast, run-off had lower Mg (t(8)=6 072,P <0 001), alkalinity (t(8)=6 201,P <0 001) and phosphate (t(8)=3 547,P =0 008). The pH values for run-off were circumneutral (6 12–7 47) and consistently lower than those for control water (t(8)=2 691,P =0 027). Other conven- tional chemistry parameters were not signiﬁcantly different among treatments, including Ca (t(8)=0 121,P =0 907) and hardness (t(8)=1 159, P =0 280). At the outset of exposures, dissolved oxygen levels ranged from 8 1to107mgO2 L 1 and were main- tained above 6 5mgL 1 with additional aeration as needed. Collected highway run-off had a more pyrogenic (or combustion-driven) PAH proﬁle relative to the artiﬁcial storm water mixtures, as evidenced by a relative enrich- ment of higher molecular weight (5- and 6-ring) com- pounds and fewer low molecular weight (2- and 3-ring) compounds (Fig. 2). Bile PAH metabolites were not sig- niﬁcantly different between ﬁsh exposed to control well water or storm water run-off after a 4-h exposure (Fig. 3). Although the measured concentrations of PAH metabo- lites in the bile of ﬁsh exposed for 24 h to the PAHs/met- als mixture were elevated relative to paired controls, the difference was not signiﬁcant (Student’s t-test;P =0 1, 0 14, 0 11 for phenanthrene, benzo-a-pyrene and naph- thalene metabolites, respectively). This indicates that low-level PAH exposures typical of urban run-off do not produce large increases in measurable bile metabolites, consistent with bile PAH metabolite measurements from symptomatic coho previously collected during ﬁeld sur- veys of urban spawning habitats (Scholz et al.2011). Notably, in 2012, the levels of 2- and 3-ring PAHs in the control exposure water were unexpectedly elevated rel- ative to all other control treatments (Fig. 2, arrow). This was attributed to the recent drilling of a new well at the Suquamish hatchery facility. Measured PAH levels in the well water declined sharply over a time span of 2 weeks (Fig. 2), and adult coho controls that were exposed dur- ing the interval did not exhibit behavioural symptoms (Fig. 1). Whereas the levels of dissolved-phase Cd and Pb were generally lower in collected run-off relative to all of the artiﬁcial storm water mixtures (Fig. 2), Cu and Ni in run- off spanned the range of these two metals in the environ- mentally relevant mixture. Zinc levels in run-off were Fig. 2.Dissolved metal (left column) and dissolved polycyclic aromatic hydrocarbon (right column) concentrations summarized by ring number for adult exposures to well water controls, polycyclic aromatic hydro- carbons (PAHs)/metal mixtures, highway run-off and ﬁltered run-off. Closed sym- bols indicate dead or symptomatic individ- uals were observed in the exposure. Lines connect paired highway run-off and ﬁl- tered run-off from the same collection. Control points are the mean of samples collected each year. The number of mean values below the reporting limits (i.e. non- detects) is indicated by # ND. ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 403 EXHIBIT 5 58 of 291 higher, and within the range of corresponding Zn levels in the high-metal mixture. The concentrations of metals in the gills of storm water-exposed and unexposed coho (4 h) were not signiﬁcantly different (Student’s t-tests, P >0 05; Fig. 3) and, in both cases, were lower than gill metal levels measured from symptomatic spawners col- lected from the ﬁeld (Scholz et al.2011). Similarly, expo- sures to the environmentally relevant artiﬁcial storm water mixture of PAHs/metals did not produce a signiﬁ- cant accumulation of metals in the gills, with the excep- tion of Ni (Student’s t-test,P =0 017). For the high metals mixture, only gill Cd, Cu and Pb levels were signif- icantly elevated relative to controls (Student’s t-test; P =0 002, 0 018, 0 003 for Cd, Cu and Pb, respectively). Filtering collected highway run-off through the biore- tention columns reduced total PAHs by 94% and total metals by 58%. As expected, removal efﬁciency varied for different contaminants. For example, the soil columns removed lower molecular weight PAHs less efﬁciently than higher molecular weight PAHs (e.g. 81–89% for 2–3 ring PAHs vs. 93% removal of 4- to 5-ring PAHs; Table S5). Notably, the medium in the bioretention col- umns was a source (i.e. an exporter) of total Ni to the treated run-off, resulting in a 57% increase over the pre- ﬁltration input (Table S3). All other total metals decreased by an average of 48–88% across the two events in the order of Cd <Pb <Cu <Zn. For each of the met- als, concentrations in the dissolved phase also declined after soil column inﬁltration (Table S3). In addition to exporting Ni, the bioretention columns were also a source of DOC (post-/pre-ﬁltration increase of 164%), alkalinity (+29%), Ca (+60%), Mg (+372%), ortho-P (+4000%) and increasing hardness (+107%). By contrast, column inﬁltra- tion reduced the ammonia content of storm water by 92% (Table S2). Discussion We have conﬁrmed that controlled exposures to untreated urban run-off are sufﬁcient to reproduce the coho spaw- ner mortality syndrome. Adult coho became symptomatic and died within a few hours of immersion in collected storm water. Mortality rates were 100% for exposed ﬁsh vs. 0% in control ﬁsh held in clean well water, and these results were consistent across nine distinct rainfall inter- vals that spanned three consecutive autumn spawning runs. As evidence that one or more toxic chemical con- taminants are causal, pre-treating the highway run-off with soil bioinﬁltration completely prevented the acutely lethal impacts on coho spawners. Surprisingly, coho did not develop symptoms in response to artiﬁcial mixtures of PAHs and metals, even at concentrations that were higher Fig. 3.Left column shows the relative measured concentrations of metals in adult coho salmon gill tissue for Cd, Cu, Pb, Ni and Zn (lgg 1). Control values are means of control tests run in 2011 and 2012. Closed symbols indicate dead or symp- tomatic individuals observed in the expo- sure. The right column shows bile ﬂuorescent aromatic compounds (FACs) detected at naphthalene (NPH), phenan- threne (PHN), benzo-a-pyrene (BAP) wavelengths shown as protein corrected polycyclic aromatic hydrocarbons (PAH) equivalents (ng mg 1). ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 404 J. A. Spromberg et al. EXHIBIT 5 59 of 291 than those typically measured in storm water, including the ﬁrst ﬂush. Urban run-off is chemically complex, with many chemical constituents that are very poorly charac- terized in terms of toxicity to ﬁsh. While it may take years of additional assessment to identify precisely which of these agents is killing coho, our initial results suggest that simple GSI technologies hold promise as a means to improve water quality and effectively prevent coho mor- tality in urban spawning habitats. Our ﬁnding that road run-off alone is sufﬁcient to induce the spawner mortality syndrome aligns with previ- ous evidence for a positive association between the amount of impervious surface within an urban watershed and the year-to-year severity of coho die-offs (Feist et al. 2011). It appears that other forms of water quality degra- dation are not necessary to produce the phenomenon. Consistent with this, symptomatic spawners do not show evidence of neurotoxic pesticide exposure (Scholz et al. 2011), and adult coho are not unusually vulnerable to low-level mixtures of currently used pesticides (King et al. 2013). The link to impervious run-off also discounts a role for personal care products, pharmaceuticals, and other classes of compounds that are transported to some urban streams via combined sewer overﬂows in heavy rains. As noted above, urban road run-off contains a complex mixture of chemicals, many of which originate from motor vehicles in the form of exhaust, leaking crankcase oil and the wearing of friction materials (i.e. brake pads) and tyres. We assessed the toxicity of PAH and metal mixtures because these compounds are ubiquitous in storm water and are known to be disruptive to the ﬁsh cardiovascular system (PAHs: Brette et al.2014), as well as the respiratory and osmoregulatory functions of the gill (metals: Niyogi & Wood 2004). Although bile and gill tis- sue results suggest that PAHs and some metals are bioavailable to the coho spawners (this study; Scholz et al.2011), artiﬁcial mixtures of PAHs and metals did not produce the symptoms of the mortality syndrome. Our results appear to rule out many of the PAHs that are common to urban run-off and crude oil spills (e.g. phenanthrenes). However, there may be a role for the higher molecular weight pyrogenic PAHs found in partic- ulate vehicle exhaust (i.e. soot), other than pyrene or ﬂuo- ranthene. The remaining list of potential causal chemicals is long and includes other organic hydrocarbons such as methylphenols, quinones, thiazoles, thiophenes, furans and quinolines. Given the logistical challenges associated with adult coho exposures –seasonal availability of ani- mals, large volume assays, limited number of ﬁsh, etc.–it may be years before the causal agent(s) is identiﬁed. Notably from a water resource management perspective, this will likely be a chemical or chemicals for which there are no existing water quality criteria. Biological indicators play an important role in ﬁeld assessments to document the urban stream syndrome in affected watersheds world-wide. Common examples are benthic indices of biological integrity (B-IBIs), which are used to characterize the health of streams based on the diversity and abundance of macroinvertebrates (Karr 1999). Although poor B-IBI scores are diagnostic of aqua- tic habitat degradation, they do not necessarily differenti- ate between drivers that may be chemical (i.e. pollution) vs. physical or biological. Conversely, biological indica- tors that are speciﬁc to toxic run-off may not have directly meaningful implications for individual survival, as a basis for guiding species conservation at the population and community scales. This includes, for example, the upregulation of sensitive and responsive cytochrome p450 enzymes in the livers of ﬁsh exposed in situ to certain PAHs and other contaminants that act via the aryl hydro- carbon receptor (van der Oost, Beyer & Vermeulen 2003). Coho spawners, by contrast, appear to be very sensitive ecological indicators, with a response metric that is directly attributable to toxic storm water. Moreover, the implications of widespread and recurring mortality are relatively clear at higher scales (e.g. Spromberg & Scholz 2011). Although the highway run-off used in this study (at the point of discharge) presumably contained higher concentrations of chemical contaminants than surface water conditions in urban spawning habitats, it is evident that run-off in urban waterways is not sufﬁciently diluted to protect many or most coho from premature death (Scholz et al.2011). By establishing a direct link between non-point source pollution and the mortality syndrome, our ﬁndings set the stage for future indicator studies in western North America. This includes, for example, more reﬁned predictive mapping of vulnerable habitats as a function of impervious land cover, at present and with future urban growth scenarios (Feist et al.2011). Coho survival in urban streams can also indicate the success of pollution control programmes, via GSI or other strategies. Intensive control measures will almost certainly be neces- sary, across large spatial scales, to: (i) recover viable coho populations in the built environment, and (ii) prevent the rapid future loss of coho as a consequence of expanding impervious cover in watersheds that are currently produc- tive but primarily non-urban. In the future, it may be possible to narrow the focal list of chemicals by determining more precisely why storm water-exposed coho are dying. The gaping, surface swim- ming and disequilibrium of affected spawners suggest adverse physiological impacts on the gill, the heart, the nervous system or some combination of these. An earlier forensic study found no evidence of physical injury to the gills or other tissues (Scholz et al.2011). An alternative approach would be to screen the target organs of symp- tomatic ﬁsh for changes in gene expression, and speciﬁ- cally gene sets that are diagnostic for speciﬁc categories of physiological stress (e.g. respiratory uncoupling). If the cause of death is ultimately found to be heart failure, for example, the candidate chemicals could be screened for cardiotoxic potential. It may also be possible to develop alternative exposure methods that reﬂect different sources of contaminants on roadways. This includes, for example, ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 405 EXHIBIT 5 60 of 291 large-volume suspensions of particulate soot from motor vehicle exhaust, dust from brake pad wear or ﬁne parti- cles from tyre wear. Lastly, toxic run-off is likely to represent an increas- ingly important conservation challenge for west coast coho populations in the coming years. Extant population segments are generally at historically low abundances, as evidenced by current US Endangered Species Act threat- ened designations in central and northern California, as well as north-western Oregon and south-western Washing- ton. Land cover change has been extensive in some low- land watersheds where coho spawn, as a consequence of sprawl in recent decades (e.g. Robinson, Newell & Mar- zluff 2005). Over a similar period of time, coho habitat use in areas affected by urbanization has declined sharply (Bilby & Mollot 2008). Resource managers have been aware of the urban pre-spawn mortality syndrome among adult coho since at least the 1980s (Kendra & Willms 1990). However, the extent to which recurring adult die- offs have driven down wild coho numbers in urbanizing watersheds is not presently known. Initial modelling has shown that local populations in urbanizing watersheds cannot withstand the rates of mortality observed in Puget Sound urban stream surveys since 2000 (Spromberg & Scholz 2011). However, in terms of recovery planning, this storm water-related threat has yet to be mapped out for actual coho conservation units at the sub-basin scale. In conclusion, a core objective of GSI is to slow, spread and inﬁltrate storm water. As anticipated from recent studies (e.g. McIntyre et al.2015), the experimental soil columns used here effectively prevented the acutely lethal toxicity of run-off from a dense urban arterial road. This extends the range of aquatic species and life stages that demonstrably beneﬁt from storm water bioinﬁltration. These include the early life stages of zebraﬁsh (McIntyre et al.2014), juvenile coho salmon and their macroinverte- brate prey (McIntyre et al.2015), and adult coho spawn- ers (this study). Bioretention is therefore a promising clean water technology from the standpoint of installation cost, reliability, reproducibility and scalability. However, the science of GSI effectiveness is still relatively young (Ahiablame, Engel & Chaubey 2012), and fundamental questions remain as-yet unanswered, for example how much treatment will be needed, over what spatial scales, to ensure coho salmon survival? Whereas bioretention may work well for small-footprint sites that receive mod- est inputs of storm water, they are but one of many evolv- ing non-point source pollution control and prevention methods that are currently under development (Hughes et al.2014). For the urban watersheds of the future, the coexistence of humans and wild coho will likely hinge on the success of these innovations. Acknowledgements We appreciate the technical assistance of Allisan Beck, Richard Edmunds, Tony Gill, Emma Mudrock, Tiffany Linbo, Kate Macneale, Jana Labenia, Mark Tagal, Frank Sommers, Gina Ylitalo, Daryle Boyd, Barb French, Ann England, Karen Peck, MaryJean Willis, Cathy Laetz, Sylvia Charles, William Alexander, Ben Purser, Corey Oster, Luke Williams and the Kit- sap Poggie Club. This study received agency funding from the NOAA Coastal Storms Program (National Ocean Service, Coastal Services Cen- ter), the U.S. Fish & Wildlife Service, the Puget Sound’s Regional Stormwater Monitoring Programme (RSMP as administered by the WA State Dept. of Ecology), and the U.S. Environmental Protection Agency, Region 10. Lastly, we appreciate the helpful suggestions of two anony- mous reviewers. 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Washington Department of Ecology (2012) Stormwater Management Manual for Western Washington Volume V: Runoff Treatment BMPs. Publication No. 12-10-030, 301 pp. Washington Department of Ecol- ogy, Olympia, Washington, USA. Washington State Department of Transportation (WA DOT) (2013a)2012 Annual Trafﬁc Report, 231 pp. WA DOT, Olympia, Washington, USA. Washington State Department of Transportation (WA DOT) (2013b) State Highway Log Planning Report 2012: SR2 to SR 971, 1781 pp. WA DOT, Olympia, Washington, USA. Received 2 April 2015; accepted 2 September 2015 Handling Editor: Julia Blanchard Supporting Information Additional Supporting Information may be found in the online version of this article. Table S1. Nominal concentrations (lgL 1) for metals and selected polycyclic aromatic hydrocarbons (PAHs) in the PAHs/ metals mixture and the metals-only mixture exposures. Table S2. Measured conventional water chemistry parameters in treatments used in adult coho experiments during 2012–2013. Table S3. Measured metal concentrations in treatments used in adult coho experiments during 2012–2013. Table S4. Abbreviations and polycyclic aromatic hydrocarbon (PAH) analytes, including sums of alkyl PAH isomers measured in water samples. Table S5. Measured parent and alkylated homologue polycyclic aromatic hydrocarbons (PAHs) (lgL 1) in treatments used in adult coho experiments during 2012–2013. Video S1. Video 1 of a symptomatic adult coho spawner in a Seattle-area urban stream. Video S2.Video 2 of a ﬁeld observation of a symptomatic adult coho in a Seattle-area urban stream. Video S3. Adult coho spawners exposed under controlled experi- mental conditions to either clean well water, unﬁltered urban run- off, or run-off treated using bioinﬁltration. ©2015 The Authors. Journal of Applied Ecology ©2015 British Ecological Society,Journal of Applied Ecology,53, 398–407 Toxic urban run-off and salmon survival 407 EXHIBIT 5 62 of 291 Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban Streams Blake E. Feist 1*, Eric R. Buhle 1, Paul Arnold 2, Jay W. Davis 2, Nathaniel L. Scholz 1 1 Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, Washington, United States of America, 2 Washington Fish and Wildlife Office, United States Fish and Wildlife Service, Lacey, Washington, United States of America Abstract In the Pacific Northwest of the United States, adult coho salmon (Oncorhynchus kisutch) returning from the ocean to spawn in urban basins of the Puget Sound region have been prematurely dying at high rates (up to 90% of the total runs) for more than a decade. The current weight of evidence indicates that coho deaths are caused by toxic chemical contaminants in land-based runoff to urban streams during the fall spawning season. Non-point source pollution in urban landscapes typically originates from discrete urban and residential land use activities. In the present study we conducted a series of spatial analyses to identify correlations between land use and land cover (roadways, impervious surfaces, forests, etc.) and the magnitude of coho mortality in six streams with different drainage basin characteristics. We found that spawner mortality was most closely and positively correlated with the relative proportion of local roads, impervious surfaces, and commercial property within a basin. These and other correlated variables were used to identify unmonitored basins in the greater Seattle metropolitan area where recurrent coho spawner die-offs may be likely. This predictive map indicates a substantial geographic area of vulnerability for the Puget Sound coho population segment, a species of concern under the U.S. Endangered Species Act. Our spatial risk representation has numerous applications for urban growth management, coho conservation, and basin restoration (e.g., avoiding the unintentional creation of ecological traps). Moreover, the approach and tools are transferable to areas supporting coho throughout western North America. Citation:Feist BE, Buhle ER, Arnold P, Davis JW, Scholz NL (2011) Landscape Ecotoxicology of Coho Salmon Spawner Mortality in Urban Streams. PLoS ONE 6(8): e23424. doi:10.1371/journal.pone.0023424 Editor:Howard Browman, Institute of Marine Research, Norway Received January 31, 2011;Accepted July 17, 2011;Published August 17, 2011 This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. Funding:This work was supported by the National Oceanic and Atmospheric Administration - Coastal Storms Program; U.S. Fish and Wildlife Service - National Contaminants Program; City of Seattle (Seattle Public Utilities); and the U.S. Environmental Protection Agency - Region 10. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests:The authors have declared that no competing interests exist. * E-mail: blake.feist@noaa.gov Introduction In recent decades, human population growth and development have continued to increase along the coastal margins of North America [1]. The associated changes in land cover and human land use have elevated land-based sources of pollution, and toxic stormwater runoff in particular, to become one of the most important threats to the biological integrity of basins, lakes, estuaries, and nearshore marine environments [2]. In the United States, concerns related to non-point source pollution have gained momentum over the past decade (e.g., [3,4]). This has culminated most recently in the designation of ‘‘water quality and sustainable practices on land’’ as one of nine National Priority Objectives for the newly established National Ocean Council, together with ecosystem-based management, marine spatial planning, climate change and ocean acidification, and changing conditions in the Arctic [2]. For toxic runoff, however, the connections between unsustainable practices on land and the decline of ecological resilience in aquatic habits remain poorly understood. In western North America, semelparous anadromous salmonids (Oncorhynchus spp.) typically migrate thousands of kilometers in their lifetimes. They hatch and rear in freshwater, migrate seaward to capitalize on the productivity of the oceans to grow rapidly and reach sexual maturity, and then return to their natal streams to spawn and die. Certain salmonids, including pink (O. gorbuscha) and chum (O. keta) migrate to the ocean relatively soon after hatching. Others, however, such as Chinook (O. tshawytscha), steelhead, (O. mykiss), sockeye (O. nerka), and coho (O. kisutch) may spend one or more years in freshwater lakes, rivers and streams. Because of this extended freshwater residency, juveniles of these species are potentially more vulnerable to anthropogenic modifications of freshwater habitat quality [5]. In contrast to the high mortality experienced by juvenile salmonids, mortality at the adult spawner life stage is relatively low. Familiar natural causes of mortality include predation, disease [6,7,8,9], stranding (following high flows), elevated stream temperatures, and competition – e.g., in habitats with abundant salmon returns and limited spawning substrate. Various human activities such as recreational and commercial fishing, stream dewatering, and the placement of migration barriers can also increase salmon spawner mortality. In general, however, salmon spawner mortality has not been attributed to toxic chemical contaminants in stormwater runoff – a data gap that may be due, in part, to 1) the relative rarity of salmon spawners in urban basins with poor water quality, and 2) the logistical difficulty of implementing toxicity studies on migratory, seawater-to-freshwa- ter transitional adults. The exception is a recently documented phenomenon of returning adult coho salmon dying at high rates in urban and urbanizing streams in lowland Puget Sound region, which includes PLoS ONE | www.plosone.org 1 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 63 of 291 the greater Seattle metropolitan area [10]. Coho return to small coastal stream networks to spawn each fall. Entry into freshwater is triggered by early autumn rainfall and rising stream flows. Since there had been extensive habitat degradation and loss in these lowlands, many basins were targeted for stream restoration projects in the 1990s. Subsequent surveys to evaluate project effectiveness discovered that many coho salmon were dying in newly-accessible stream reaches before they were able to spawn – i.e., female carcasses were found in good condition (ocean bright colors) with skeins (membrane or sac that contains the eggs within the fish) filled with unspawned eggs [10]. In addition, affected coho from several different urban basins showed a similar progression of symptoms leading up to death, including disorientation, lethargy, loss of equilibrium, mouth gaping, and fin splaying. Systematic daily spawner surveys in recent years (2002–2009) have shown that adult mortality rates in urban streams are consistently high (relative to spawning coho salmon in more pristine areas), ranging from ,25–90% of the total fall runs [10]. Mortality rates of this magnitude likely have important negative consequences for maintaining viable coho populations [11]. Consistent with this, most coho mortalities observed over the past decade were spawners that strayed (did not home to their natal stream reaches) into these restored urban freshwater habitats. The precise underlying cause of recurrent coho die-offs remains under investigation. An initial weight-of-evidence forensic study has systematically ruled out stream temperature, dissolved oxygen, poor overall spawner condition, tissue pathology (e.g., gill), pathogen prevalence or disease, and other factors commonly associated with fish kills in freshwater habitats (Scholz et al., unpublished data). These findings, together with the rapid onset of the syndrome, the nature of the symptoms (e.g., gaping and disequilibrium), and the consistent re-occurrence within and between urban basins over many years together point to toxic stormwater runoff from urban landscapes as the likely cause of coho spawner mortality. Urban runoff and stormwater-influenced combined sewer overflows (CSOs) contain an exceptionally complex mixture of chemical contaminants. Specifically, urban streams are receiving waters for runoff and discharges containing pesticides [12], metals [13], petroleum hydrocarbons [14], plasticizers, flame-retardants, pharmaceuticals, and many other potentially toxic chemicals. The list of possible causal agents is therefore long. The above chemical complexity notwithstanding, there are several reasons to suspect motor vehicles as sources of toxics that are killing returning coho. Vehicles deposit many compounds on road surfaces via exhaust emissions, leaking fluids, and the wearing of tires, brake pads and other friction materials [15]. Emissions contain nitrogen and sulfur dioxide, benzene, formaldehyde, and a large number of polycyclic aromatic hydrocarbons (PAHs). Fluids, including antifreeze and motor oil, contain ethylene and propylene glycol and PAHs. Tire wear releases zinc, lead, and PAHs onto road surfaces [16], and brake pad wear is a major source of copper, zinc, nickel, and chromium [16,17]. Collectively, these contaminants accumulate on streets and other impervious surfaces until they are mobilized by rainfall and transported to aquatic habitats via runoff. Polycyclic aromatic hydrocarbons and metals such as copper are known to be toxic to fish, although acute lethality usually occurs at exposure concentrations that are higher (by orders of magnitude) than those typically detected in urban streams. It is likely that fall stormwater pulses contain higher concentrations than winter and spring due to the potential buildup of contaminants during the relatively dry summer months. Although the adult die-off phenomenon has been observed in all Seattle-area urban streams where coho salmon occur, the overall rate of mortality has varied among basins. In qualitative terms, a higher proportion of returning animals have survived to spawn in basins that have more open space (e.g., parks and woodlands). Conversely, mortality rates have been consistently higher in basins with proportionately greater ‘‘urban’’ land cover and land uses. This raises the possibility of a quantitative relationship between discrete basin characteristics and coho survival and spawning success. Such a relationship would be important for several reasons. First, if coho mortality is significantly correlated with one or more land cover or land use variables, the latter could be used to identify unmonitored lowland basins where coho populations are at greatest risk. Second, it could provide a means to evaluate how future human population growth and development might impact wild coho populations in Puget Sound (and elsewhere) that are currently healthy. Finally, it could narrow the list of potentially causative pollution sources in urban basins, thereby focusing future toxicological studies to identify the specific contaminants involved. In this study we performed a spatial analysis to identify landscape variables that correlate most closely with surveyed rates of coho spawner mortality across six different basins in Puget Sound. The variables included land use and land cover, tax parcel types, roadways, and impervious surfaces. We then used the information from these correlations to generate spatially explicit predictions of recurrent spawner losses in unmonitored basins throughout the four most densely populated counties in the greater Seattle metropolitan area. Materials and Methods Study Sites We characterized habitat conditions within the drainage basins from streams at six sites in the Puget Sound lowlands (Figure 1). We chose these sites because coho spawner mortality has been monitored at these locations for several years (2000–2009; [10]). The sites represent a wide range of anthropogenic alteration, from highly urbanized (e.g., Longfellow Creek) to relatively undisturbed (e.g., Fortson Creek). Fortson Creek is considered a non-urban site, whereas the other five sites are urban streams and have varying degrees of development. The urban streams have all been a focus of varying restoration project efforts aimed at enhancing habitat quality for anadromous Pacific salmon. With the exception of the relatively unaltered Fortson Creek site, all site basins had impervious surface proportions well above the levels (5–10%) commonly associated with the decline of biological integrity in streams [18,19]. Confirmed observation of the coho spawner mortality syndrome (see below) within a stream system was a key factor in study site selection. Importantly, natural production of coho in Seattle-area urban streams is very low. Not unexpectedly, recent modeling has shown that local coho population abundance declines precipitous- ly at rates of spawner mortality documented for these drainages [11]. The adult returns to these streams are thus likely to be animals straying into sink or attractive nuisance habitats. Conversely, the syndrome has not been documented in streams where coho are relatively abundant – i.e., non-urban basins, as confirmed by a full season of daily stream surveys on Fortson Creek. Therefore, to evaluate the phenomenon in relation to land cover, we were constrained to streams where coho are affected, even if adult returns to these basins were low in certain years. Lastly, there is no evidence that the mortality syndrome is related to the origin of the spawners (i.e., hatchery vs. wild fish). For example, artificially propagated coho that return as adults to regional hatchery facilities in non-urban basins are unaffected. Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 2 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 64 of 291 Study Subjects Coho salmon in this study were all within the Puget Sound/ Strait of Georgia Evolutionarily Significant Unit (ESU). An ESU is defined as a group of populations that 1) are substantially reproductively isolated from conspecific populations and 2) collectively represent an important component in the evolutionary Figure 1. Six study sites where coho spawner mortality was monitored and landscape conditions were quantified.Main map depicts the Greater Seattle Metropolitan Area in Washington State, which is within the Puget Sound/Georgia Basin of the Pacific Northwest, United States of America (USA). Inset map illustrates location of the study sites within Washington State and the location of Washington State within the USA. For reference, red shading on main map represents the relative intensity of urbanization (light-medium and dense urban [23,24]). Drainage basins depicted in yellow shaded polygons represent the total basin flowing into a given stream reach site. Key for site numbers: 1=Des Moines; 2=Fauntleroy; 3=Fortson; 4=Longfellow; 5=Piper’s; and, 6=Thornton Creek. doi:10.1371/journal.pone.0023424.g001 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 3 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 65 of 291 legacy of the species [20]. Currently, Puget Sound/Strait of Georgia coho are designated a ‘‘species of concern’’ under the U.S. Endangered Species Act [21]. Coho typically spawn in small (lower order) streams in the Puget Sound lowlands in late fall and early winter and their fry emerge from stream substrates from March to May. Fry reside in riverine habitats for 14–18 months, smolt, migrate to marine environments where they grow rapidly and mature (16–20 months), and finally migrate to their natal basins where they spawn and die [22]. The adult spawners from the six study basins were both marked (adipose fin clipped) and unmarked, suggesting a mix of hatchery and wild origins. Coho Spawner Mortality We used existing monitoring data collected as part of daily and weekly spawner surveys in each of the six study locations (Table 1). Data were collected during the fall spawning season from 2000– 2009 by Seattle Public Utilities (SPU), the Wild Fish Conservancy, and the Northwest Fisheries Science Center (NWFSC). Streams were checked every few days in the early fall (usually the first or second week in October, depending on rainfall) until the first adult coho was observed. The streams were then surveyed daily for the duration of the fall run, until the last carcass was documented, typically in the first or second week of December. For several years, biologists working for the City of Seattle (Wild Fish Conservancy) also surveyed many of the same urban streams for coho spawner mortality on a weekly basis. Side-by-side compar- isons of daily and weekly survey data (e.g., for Longfellow Creek in 2005 and 2007) revealed practically no loss of carcasses to scavengers. Accordingly, we included the weekly survey data in our analyses. The entirety of the available spawning habitat within a given urban drainage was surveyed for premature adult coho mortality. For some streams, including Longfellow Creek, mid-stream barriers to upstream migration confined adults to the lower portions of the drainage. This made it possible, in the course of a few hours as part of a daily survey, to inspect all sections of the stream that 1) had a gravel substrate suitable for redds (spawning ‘‘nests’’ built by females), and 2) were focal areas for repeated (year-to-year) redd building during successive spawner runs. Monitoring data were not collected at all sites for all years (Table 1). Mortality among returning coho was quantified only for females on the basis of egg retention – i.e., the number of partially spawned or unspawned female carcasses observed in streams over an entire spawning season. Notably, the total number of returning adults was low for some years and some basins (Table 1). Nevertheless, the aggregate spawner survey data used in this analysis are the most comprehensive currently available. Geospatial Datalayers We used existing geospatial datalayers as our source of potential predictor variables and as a proxy for habitat type and condition. The datalayers were generated by a variety of organizations for planning and analytical purposes, making them suitable for running spatial analyses on habitat. They were also available over the entire spatial domain of our predictive model. We used four geospatial datalayers: Land-cover of the Greater Puget Sound Region [23,24]; impervious and impacted surfaces [25]; property type (compiled from King [26], Kitsap [27], Pierce [28] and Snohomish county [29] tax parcel databases), and roadways (Puget Sound Regional Council; PSRC [30]). The Land-cover of Puget Sound datalayer is the highest quality and most accurate depiction of land use and land cover in the Puget Sound lowlands. The datalayer used 30 m gridded LAND- SAT TM imagery from 2002, which was extensively analyzed and corrected to produce an accurate (83% overall accuracy, [24]) depiction of land use and land cover conditions. To reduce the total number of potential predictor variables, we only used the dense urban (.75%); light to medium urban (,75%); and grass, crops and/or shrubs categories. We also combined the mixed and deciduous forest with the coniferous forest category and named it forests. The impervious and impacted surfaces datalayer was derived from a 2001 LANDSAT TM image with 30 m pixels and an accuracy of 83–91% [25]. This datalayer depicts high to completely impermeable surfaces such as building roofs; concrete or asphalt roads and parking lots; concrete, asphalt or brick sidewalks, pedestrian walkways, and malls; etc. One of the limitations of these two datalayers was that the pixel size of the source LANDSAT TM imagery is 30 m, so smaller Table 1.Coho spawner mortality proportion and cumulative number of female carcasses enumerated (in parentheses) by site (columns) and year (rows). Des Moines Fauntleroy Fortson 1 Longfellow Piper’s Thornton 2000 -0.25 (12)-0.74 (135)0.18 (17)0.88 (33) 2001 -0.22 (9)-0.61 (111)0.70 (37)0.82 (11) 2002 -0.00 (1)0.01 (114) a 0.86 (57) a 0.60 (10)080 (5) 2003 -(0)-0.67 (18) a 0.00 (1)1.00 (2) 2004 0.63 (30) a (0)-0.89 (9) a 0.33 (3)1.00 (1) 2005 -0.75 (4)-0.72 (75) a 0.75 (4)0.50 (8) 2006 -(0)-1.00 (4) a 1.00 (9) a 1.00 (4) 2007 - 0.75 (4) - 0.73 (41) a 0.20 (5)0.80 (5) 2008 ---0.67 (12) a -1.00 (2) 2009 ---0.78 (36) a -- Overall 0.63 (30) 0.37 (30) 0.01 (114) 0.72 (498) 0.57 (86) 0.83 (71) A dash (-) indicates survey was not conducted for that year/site. aNorthwest Fisheries Science Center (NWFSC) daily surveys, all others were weekly and collected by Seattle Public Utilities (SPU) or the Wild Fish Conservancy [51,52]. 1Non-urban site. doi:10.1371/journal.pone.0023424.t001 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 4 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 66 of 291 features, such as roads and precise land cover boundaries, were not adequately captured. In order to address this deficiency, we analyzed property types and roadways, as they are represented as precise polyline and polygon delineations of the corresponding land cover variables. The boundaries in these geospatial datalayers were derived from precise survey data from major metropolitan areas, collected over many years by King, Kitsap, Pierce and Snohomish Counties. The property types (parcels) datalayer was based on ground surveyed delineations of property, which are used for taxation purposes, with positional accuracy of +/212 m or less [26,27,28,29]. The original number of parcel types described by each county was between 103 and 292. Using the descriptions in the documentation that accompanied the datalayers, we were able to place each of the original parcel types into one of the five following categories: apartments and condominiums; commercial; industrial; parks and open space; and, residential. The roadways datalayer was based on ground surveyed road and street centerlines. Each segment had a corresponding functional classification (FC##) code and width, as defined by the Federal Highway Administration [31] Highway Performance Monitoring System, and the Puget Sound Regional Council [30], respectively. We reduced the original nine functional classification types down to two categories: 1) heavily used roads (rural minor collector [FC08]; urban principal arterial - interstate [FC11]; urban principal arterial - other freeways and expressways [FC12]; urban principal arterial - other [FC14]; urban or rural minor arterial [FC16 or FC06]; urban collector [FC17]); and, 2) urban or rural local access roads (FC09 or FC19). We then calculated the total area (total length of given street centerline segment multiplied by its width) of each street functional classification for each corresponding site basin. Spatial Analyses We defined the area of influence of the surrounding landscape for each site as the total area draining into that site (basin). Drainage basins for each site were generated using the ‘flowaccumulation’ command in Environmental Systems Research Institute (ESRI) ArcGIS (v. 9.3). We used a United States Geological Survey (USGS) 10 m digital elevation model (DEM) as the underlying terrain for generating basins. We then intersected the corresponding basin boundary for each of the six sites with each of the geospatial datalayers and their associated categories using ArcGIS. We quantified each geospatial datalayer and its associated category in a given basin as the fraction or proportion of the total area of the basin occupied by that geospatial datalayer or category. Longfellow Creek stood apart from the other sites in terms of the accuracy of the flow accumulation model because an unknown fraction of stormwater runoff in this drainage is diverted into the municipal sewer system. Therefore, the theoretical basin area, based on the terrain represented in the DEM, was not as representative of the true basin area compared with the other five sites. Statistical Analyses We used generalized linear mixed-effects models (GLMMs; [32,33]) to test the relationships between geospatial variables and coho spawner mortality. The response was binomial (observed number of female spawner mortalities each year, given the total number of female coho that returned to each site) and the models used a logit link function. All models included a random effect of site on the intercept, which accounts for nonindependence of the repeated samples taken at each site. We constructed a set of 139 candidate models by considering all combinations of the 12 predictors taken one, two, three or four at a time, with the restriction that a model could include at most one predictor from each of the four geospatial datalayers (land cover, impervious surfaces, property types, and roadways). We also excluded combinations of predictors that had a pairwise Spearman rank correlation exceeding 0.9 in absolute value. The candidate set included an intercept-only model as a no-effect baseline against which we could assess the predictive power of the geospatial variables. We fitted the models using the Laplace approximation to the marginal likelihood [32] in the lme4 package in R [34,35]. We then used Akaike’s information criterion, corrected for sample size (AICc) to rank the strength of evidence for each candidate model based on the data. Akaike’s information criterion is a weight-of- evidence measure that reflects the balance between a model’s goodness-of-fit to the data and its parsimony (i.e., number of parameters). Lower AICc values indicate greater support, and are reported as differences (DAICc) relative to the best (smallest) value in the candidate set. We computed Akaike weights [36], which represent the relative support for each model, normalized so the weights sum to unity across the candidate set. We used these weights to compute model-averaged estimates and unconditional standard errors (SEs) for the fixed regression coefficients, and we quantified the relative importance of each predictor using variable weights (i.e., the summed Akaike weights of all models that included that predictor; [36]). These model averaging calculations were based on the 95% confidence set of models (i.e., the top- ranked models whose cumulative Akaike weight is 0.95), after re- normalizing the weights. Mapping coho spawner mortality Using the fitted models, we built a map of predicted coho spawner mortality throughout the four counties (King, Kitsap, Pierce and Snohomish) representing much of the Puget Sound lowlands, by applying the GLMM equations to geospatial data from unmonitored basins. We used basins delineated in the National Hydrography Dataset Plus [37] as the underlying mapping unit (300 ha mean, 466 ha SD) and intersected the NHDPlus datalayer with each of the geospatial datalayers used in the statistical analyses. Within the four-county region, we only made spawner mortality predictions in basins where coho salmon presence has been documented, based on current geospatial datalayers generated by the Washington Department of Fish and Wildlife [38]. We then calculated the proportion of each basin that was covered by the selected landscape feature. We generated predicted values of the proportion of mortalities from each model in the 95% confidence set and then model-averaged these values using the normalized Akaike weights [36]. These predictions apply to the average basin in the Puget Sound coho ESU with some given set of habitat conditions, in the sense that the random effect of site was set to zero. To be conservative in representing the precision of the predicted values, we divided the calculated rates of likely coho spawner mortality into three bins:,10%, 10–50%, and .50%. These break points were chosen somewhat arbitrarily to represent low, medium and high spawner mortality rates. Results We found strong associations between land use and land cover attributes and rates of coho spawner mortality. Across the 95% confidence set of fitted models, three variables were particularly important for predicting mortality based on high variable weights: impervious surfaces, local roads, and commercial property type (Table 2 and Figure 2). There was substantial model selection Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 5 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 67 of 291 uncertainty, reflected in a large 95% confidence set and large number of models with DAICc,2.0 (37 and 8 of 139 candidate models, respectively; Table 3). In addition, although we excluded highly multicollinear combinations of variables (|r|.0.9), many variables were still strongly correlated, resulting in unstable parameter estimates and large unconditional SE estimates (Table 2). Nonetheless, predictive models that included land use and land cover attributes as predictors were clearly superior to the intercept-only model (DAICc =20.4; Table 3), supporting the association of these variables with coho mortality. While the multicollinearity among potential predictors made causal interpretation of the models difficult, it did not preclude predictions of where coho salmon are likely to be affected along an urbanization gradient. Not surprisingly, the highest predicted mortality rates were clustered around the major metropolitan areas of eastern Puget Sound, contained within Snohomish, King, Kitsap, and Pierce counties (Figure 3). In addition, there is a significantly sized area in Eastern Puget Sound that has considerable proportions of the variables (local roads, impervious surface and commercial parcels) most correlated with substantial mortality rates. It is important to note that these predicted values have substantial associated uncertainty and should therefore be interpreted cautiously; however, it is reasonable to use them for assigning the break points for the low, medium, and high mortality rate categories represented on the map. Discussion Overall, we have used conventional tools in landscape ecology to shed light on an unusually complex ecotoxicological challenge. Our analyses strongly suggest that specific characteristics of basins in the Puget Sound lowlands are linked to the die-offs of coho spawners that have been widely observed in recent years. Across basins, the strength of the association is greatest for impervious surfaces, local roads, and commercial property. We did not evaluate hydrologic or geomorphic basin characteristics as part of our analysis. Nevertheless, our findings support the hypothesis that coho are being killed by as-yet unidentified toxic chemical contaminants that originate from these types of surfaces and are transported to salmon spawning habitats via stormwater runoff. Our results extend a large body of scientific information linking urbanization (broadly defined) and degraded water quality to a loss of biological integrity (sensu Karr [39]) and productivity in freshwater stream networks [18,40,41]. Previous studies have generally related land use and land cover variables to macroin- vertebrate assemblages in streams [42], or to the relative abundance of salmon and other fish (e.g., [22,43,44]). The present analysis is novel because it relates basin characteristics directly to salmon health and survival, versus species presence or absence. Moreover, it offers new insights on the water quality aspects of urban runoff. The focus of most salmon restoration projects is physical characteristics of spawning and rearing habitat [45]. Most salmon specific restoration projects are deemed successful if they simply restore the physical habitat to a suitable state for a given species [46]. Our study suggests that suitable spawning and rearing habitat may not be supportive of coho salmon persistence when the surrounding landscape is urbanized. The linkages between increased impervious coverage within a basin, increased storm- water runoff, altered hydrologic processes, and ecological decline are well established (e.g., [18]). However, stormwater impacts encompass both physical and chemical drivers of decline, and it can be difficult to distinguish between these via in situ assessments because stream invertebrate communities integrate both stressor categories. Coho salmon spawners, by contrast, appear to be promising and specific sentinels for the degraded water quality aspect of urban runoff. Compared to macroinvertebrate sampling and taxa identification, the coho mortality syndrome is relatively easy and inexpensive for non-specialists to monitor in the form of digital video recordings of symptomatic fish, or the presence of unspawned female carcasses in streams. Interestingly, the mortality syndrome appears to be specific to coho salmon. For example, there were temporally overlapping runs of coho and chum salmon (O. keta) in Piper’s Creek in the fall of 2006. Whereas all of the adult coho succumbed to the mortality syndrome, the chum were unaffected, with nearly all surviving to spawn (130 of 135 spawned out female carcasses; Scholz et al., unpublished data). Consistent with this, the survey Table 2.AIC weights, model averaged parameter estimates and unconditional confidence intervals for each variable, ranked by AICc weight. Model AICc Averaged Unconditional Datalayer Variable weight coefficient SE Impervious Impervious surfaces 0.7158 16.8425 14.5376 Roadways Local roads 0.5647 215.6199 68.3331 Property type Commercial 0.5107 7.9375 8.2616 Land cover Dense urban 0.3865 27.7776 16.1614 Property type Apartments & condominiums 0.2409 29.5330 31.1917 Roadways Heavily used roads 0.2019 5.3445 31.5073 Land cover Forest 0.1163 20.7793 6.2249 Land cover Light to medium urban 0.1149 0.3250 2.9751 Land cover Grass, shrubs & crops 0.0993 0.1664 5.4517 Property type Residential 0.0975 0.0738 16.8920 Property type Industrial 0.0547 20.2475 4.7008 Property type Parks & open space 0.0000 0.0000 0.0000 doi:10.1371/journal.pone.0023424.t002 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 6 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 68 of 291 teams have not observed the characteristic symptoms (e.g., surface swimming, gaping) among other fish species that inhabit urban streams such as sticklebacks and cutthroat trout. Not only are coho unusual in this respect, the phenomenon appears to be restricted to the adult life stage. In the fall of 2003, surface flows from Longfellow Creek were diverted through streamside sheds housing aquaria that contained individual juvenile coho from the NWFSC hatchery. The juveniles (n=20) were maintained and observed daily throughout the fall spawner run. Overall juvenile survival was 100%, and the juveniles behaved normally, even on days when symptomatic adults were observed in the nearby stream (Scholz et al., unpublished data). The underlying reasons Figure 2. Female coho spawner mortality as a function of the proportion of each of the top three predictors in a given site basin, at the six study sites.Individual points correspond to specific years for each site. Mortality expressed as proportion of all returning females that died in a given year. Solid circle=Des Moines; hollow circle=Fauntleroy; solid square=Fortson; hollow square=Longfellow; solid triangle=Piper’s; hollow triangle=Thornton Creek. doi:10.1371/journal.pone.0023424.g002 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 7 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 69 of 291 for the syndrome’s surprising uniqueness to adult coho are not yet known. Daily or weekly stream surveys are labor intensive, and for this reason only a subset of urban drainages in Puget Sound have been monitored to date. The GIS-based mapping tool developed for this study can be used to focus future monitoring efforts on basins with a higher likelihood of coho die-offs based on land cover attributes. In addition to the basins we have identified within the range of the Puget Sound/Georgia Basin ESU, this approach could be extrapolated to other geographic areas where coho return to spawn along a gradient of urban growth and development. This includes, for example, coho from the Lower Columbia River ESU, a threatened population segment with a spawner range encom- passing the greater metropolitan area of Portland, Oregon. Overall, future surveys will ground-truth initial model outputs and provide additional data that can be used to improve the predictive accuracy of the mapping tool. Our findings have two near-term applications. First, they identify likely ‘‘hotspots’’ for coho spawner mortality throughout central Puget Sound. Given that recurring adult losses at a rate greater than approximately 10% are likely to substantially reduce local population abundances, the high mortality basins in Figure 3 (10–50% and .50% predicted mortality categories) may represent sink habitats for the Puget Sound/Georgia Basin ESU. This is an important consideration for coho recovery planning at the local, county, and regional scales. Second, our results indicate areas where toxic runoff could potentially undermine stream restoration efforts - specifically, strategies that improve physical and biological habitat conditions (flow, connectivity, channel complexity, ripar- ian function, etc.) as a means to boost coho population productivity. The potential influence of rainfall, including timing, frequency, and individual storm intensity, remains an area of active investigation. Throughout the years of stream surveys, it has been qualitatively evident that rainfall influences the mortality syndrome. For example, salmon that arrive and enter a stream during an extended dry interval (a week or more) often survive and then become symptomatic and die when it next rains (Scholz et al., unpublished data). One of our aims in surveying Longfellow Creek (the stream with the most abundant overall returns) for more than a decade was to evaluate inter-annual variation in coho spawner mortality in relation to rainfall. However, a quantitative analysis has proven problematic due to highly variable rainfall patterns in combination with low adult returns in some years. It is clear, however, that the syndrome is not a simple first-flush phenomenon. In most years, both egg retaining and spawned out carcasses were observed across the 8– 10 week fall run, irrespective of the number and size of rain events over that interval. Over the longer term, an approach similar to the one developed here could be used to forecast the likely impacts of future human population growth and development on Puget Sound coho populations that are currently healthy. For example, the expansion of local road networks is a core focus for urban growth planning, and these projections could serve as a basis for evaluating how and where coho spawner mortality will increase under different growth management scenarios. This, in turn, would inform strategies to reduce or mitigate toxic runoff in highly productive basins, in advance of expanding transportation infrastructure – i.e., prevention vs. costly retrofits to the built environment. Also, our modeling approach could be expanded to include the timing and intensity of rainfall as potential drivers for coho spawner mortality. Rainfall patterns may be a key determinant of stormwater quality, although more work in this area is needed. Climate change is expected to shift regional rainfall patterns, and it should be possible to explore how this will interact with changing land cover (urbanization) to influence stormwater quality and toxic runoff to coho spawning habitats. Table 3.Summary of the 95% confidence set (37 of a total of 139 candidate models) of candidate models used to generate map of mortality rates, showing intercepts, estimated coefficients,DAICc and wAICc. Intercept only model included at bottom for reference. Model Equation DAICc wAICc a+b 24.5664+19.76(a)+44.41(b) 0.000 0.0933 c+d+b 23.92152109.56(b)+48.75(c)229.98(d) 0.046 0.0912 c+e+f 23.9355+12.94(c)240.15(e)+38.61(f) 0.372 0.0775 c+d+a 24.4921+12.61(a)+14.03(c)27.54(d) 0.579 0.0698 c+g+a 24.4858+14.31(a)+5.23(c)+3.62(g) 0.669 0.0668 h+a+b 22.6065+15.89(a)+30.87(b)22.38(h) 1.150 0.0525 c+a+b 24.6629+16.37(a)+35.26(b)+2.70(c) 1.357 0.0473 d+a+b 24.7001+17.52(a)+43.83(b)+1.62(d) 1.576 0.0424 c+e 24.5943+19.70(c)253.28(e)2.425 0.0277 c+d+i+b 23.0628283.44(b)+56.38(c)240.28(d)27.82(i) 2.485 0.0269 c+j+i+b 27.30552130.72(b)+21.23(c)+19.12(i)+10.65(j) 2.543 0.0262 c+d+k+b 23.9266294.52(b)+43.32(c)225.00(d)21.60(k) 2.613 0.0253 j+a+b 24.5174+20.03(a)+43.79(b)20.52(j)2.752 0.0236 c+d+a+b 24.0864+3.99(a)276.44(b)+38.23(c)223.27(d) 2.885 0.0221 c+d+a+f 24.7368+15.57(a)+16.88(c)29.22(d)222.10(f) 2.925 0.0216 c+d+e+b 23.96072100.49(b)+46.40(c)227.43(d)25.54(e) 2.954 0.0213 c+d+e+f 23.8347+12.37(c)+0.49(d)240.69(e)+39.28(f) 3.280 0.0181 c+g+e+f 23.8534+12.93(c)240.45(e)+38.73(f)20.18(g) 3.294 0.0180 c+j+e+f 23.9360+12.94(c)240.28(e)+39.36(f)20.31(j) 3.326 0.0177 c+g+a+f 24.6143+16.25(a)+5.79(c)213.40(f)+4.06(g) 3.378 0.0172 c+d+i 21.1996+64.26(c)255.97(d)224.83(i)3.423 0.0168 h+i+b 9.39112153.97(b)217.49(h)+15.89(i)3.858 0.0136 h+e+f 2.2747227.99(e)+47.38(f)27.31(h)3.931 0.0131 h+a 1.2512+8.63(a)26.13(h)4.028 0.0124 c+j+a+b 24.5887+16.71(a)+34.25(b)+2.72(c)20.75(j) 4.299 0.0109 h+k+b 5.8364227.35(b)211.39(h)25.97(k)4.837 0.0083 c+j+e 24.4356+18.70(c)250.31(e)+1.33(j)4.915 0.0080 c+j+k+b 22.4511252.30(b)+20.45(c)213.34(j)210.60(k) 4.937 0.0079 c+d+e 24.7362+20.37(c)20.45(d)253.43(e)5.141 0.0071 c+e+b 24.468021.36(b)+19.52(c)252.48(e)5.158 0.0071 c+g+e 24.5797+19.68(c)253.23(e)20.02(g)5.188 0.0070 h+e+b 8.1285220.52(b)245.07(e)214.67(h)5.509 0.0059 c+k 24.3426+13.30(c)25.31(k)5.649 0.0055 c+i+b 25.67752141.73(b)+22.77(c)+17.24(i) 5.821 0.0051 c+k+b 23.9708212.84(b)+14.63(c)26.46(k)5.896 0.0049 h+a+f 0.4930+6.87(a)+19.67(f)25.22(h)6.083 0.0045 c+d+i+f 21.0499+68.65(c)259.91(d)26.04(f)226.58(i) 6.343 0.0039 Intercept only N/A 20.428 0 Model weights shown here are re-normalized for the set of 37 top-ranked models shown. a=commercial; b=local roads; c=impervious; d=dense urban; e=apartments and condominiums; f=heavily used roads; g=light to medium urban; h=forest; i=residential; j=grass, crops and/or shrubs; and, k=industrial. doi:10.1371/journal.pone.0023424.t003 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 8 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 70 of 291 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 9 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 71 of 291 While not definitive, our results reinforce the parsimonious explanation that coho deaths are caused by one or more contaminants originating from motor vehicles. As noted earlier, this is important because it narrows the list of candidate toxics in complex urban landscapes. Future toxicological studies should focus on two ubiquitous urban runoff contaminant classes in particular. The first are metals in brake pads and other vehicle friction materials. Copper, zinc, and other metals are known to specifically target the fish gill, thereby disrupting respiration and osmoregulation [47]. The second, PAHs, [14,48,49] are taken up across the fish gill, and can impair cardiac function and respiration [50]. The symptoms displayed by affected coho (surface swimming, gaping, loss of equilibrium, etc.) are consistent with a disruption of respiration, osmoregulation, or circulation, or some combination of these. Notably, PAHs and metals usually cause the above toxicological effects at concentrations well above those typically detected in urban streams. However, the majority of conventional toxicology studies using salmonids focus on freshwater species (e.g., rainbow trout) or the freshwater life stages of juvenile anadromous species. There are practically no toxicity data for coho salmon at the adult spawner stage. Many important osmoregulatory changes take place during the transition from seawater prior to spawning, and these may render adult coho more vulnerable to metals and PAHs than freshwater-resident salmonids. Adding to this complexity is the possibility of interactive toxicity (e.g., synergism) among contaminant mixtures. Studies that experimentally reproduce the familiar symptomology and mortality in adult coho, under controlled exposure conditions with environmentally realistic mixtures of metals and PAHs, will likely be necessary to definitively implicate motor vehicles. Acknowledgments We thank John Williams and an anonymous reviewer for significantly improving previous drafts of this manuscript. Disclaimer: the findings, conclusions and views expressed herein are those of the authors and do not necessarily represent those of the National Oceanic and Atmospheric Administration or the U.S. Fish and Wildlife Service. Author Contributions Conceived and designed the experiments: BEF JWD NLS. Performed the experiments: BEF ERB PA. Analyzed the data: BEF ERB PA. Wrote the paper: BEF ERB NLS. References 1. Weinstein MP, Baird RC, Conover DO, Gross M, Keulartz J, et al. (2007) Managing coastal resources in the 21st century. Frontiers in Ecology and the Environment 5: 43–48. 2. Interagency Ocean Policy Task Force (2010) Final Recommendations of the Interagency Ocean Policy Task Force. Washington, DC: The White House Council on Environmental Quality. 96 p. 3. Pew Oceans Commission (2003) America’s Living Oceans: Charting a Course for Sea Change. Arlington, Virginia: Pew Charitable Trusts. 166 p. 4. U.S. Commission on Ocean Policy (2004) An Ocean Blueprint for the 21st Century: Final Report. Washington, DC: U.S. Commission on Ocean Policy. 676 p. 5. Spromberg JA, Meador JP (2006) Relating chronic toxicity responses to population-level effects: A comparison of population-level parameters for three salmon species as a function of low-level toxicity. Ecological Modelling 199: 240–252. 6. Raverty S, Kieser D, Bagshaw J, St-Hilaire S (2000) Renal infestation with Parvicapsula minibicornis in wild sockeye salmon from the Harrison and Adams rivers in British Columbia. Canadian Veterinary Journal 41: 317–318. 7. St-Hilaire S, Boichuk M, Barnes D, Higgins M, Devlin R, et al. (2002) Epizootiology of Parvicapsula minibicornis in Fraser River sockeye salmon, Oncorhynchus nerka (Walbaum). Journal of Fish Diseases 25: 107–120. 8. Kocan R, Hershberger P, Winton J (2004) Ichthyophoniasis: An emerging disease of Chinook salmon in the Yukon River. Journal of Aquatic Animal Health 16: 58–72. 9. Keefer ML, Taylor GA, Garletts DF, Gauthier GA, Pierce TM, et al. (2010) Prespawn mortality in adult spring Chinook salmon outplanted above barrier dams. Ecology of Freshwater Fish 19: 361–372. 10. McCarthy SG, Incardona JP, Scholz NL (2008) Coastal Storms, Toxic Runoff, and the Sustainable Conservation of Fish and Fisheries. In: McLaughlin KD, ed. Mitigating Impacts of Natural Hazards on Fishery Ecosystems. Bethesda, MD: American Fisheries Society. pp 7–27. 11. Spromberg JA, Scholz NL (2011) Estimating the future decline of wild coho salmon poplulation due to premature spawner die-offs in urbanizing watersheds, of the Pacific Northwest. Integrated Environmental Assessment and Manage- ment;doi: 10.1002/ieam.219. 12. Hoffman RS, Capel PD, Larson SJ (2000) Comparison of pesticides in eight U.S. urban streams. Environmental Toxicology and Chemistry 19: 2249–2258. 13. Tiefenthaler LL, Stein ED, Schiff KC (2008) Watershed and land use–based sources of trace metals in urban storm water. Environmental Toxicology and Chemistry 27: 277–287. 14. Stein ED, Tiefenthaler LL, Schiff K (2006) Watershed-based sources of polycyclic aromatic hydrocarbons in urban storm water. Environmental Toxicology and Chemistry 25: 373–385. 15. Conko KM, Rice KC, Kennedy MM (2004) Atmospheric wet deposition of trace elements to a suburban environment, Reston, Virginia, USA. Atmospheric Environment 38: 4025–4033. 16. Davis AP, Shokouhian M, Ni SB (2001) Loading estimates of lead, copper, cadmium, and zinc in urban runoff from specific sources. Chemosphere 44: 997–1009. 17. Bourcier DR, Hindin E (1979) Lead, iron, chromium and zinc in road runoff at Pullman, Washington. Science of the Total Environment 12: 205–215. 18. Booth DB, Jackson CR (1997) Urbanization of aquatic systems: degradation thresholds, stormwater detection, and the limits of mitigation. Journal of the American Water Resources Association 33: 1077–1090. 19. Cuffney TF, Brightbill RA, May JT, Waite IR (2010) Responses of benthic macroinvertebrates to environmental changes associated with urbanization in nine metropolitan areas. Ecological Applications 20: 1384–1401. 20. Johnson O, Waples R, Wainwright T, Neely K, Waknitz F, et al. (1994) Status Review for Oregon’s Umpqua River Sea-Run Cutthroat Trout. Washington, DC: U.S. Department of Commerce. 21. National Oceanic and Atmospheric Administration (2004) Endangered and Threatened Species; Establishment of Species of Concern List, Addition of Species to Species of Concern List, Description of Factors for Identifying Species of Concern, and Revision of Candidate Species List Under the Endangered Species Act Federal Register. pp 19975–19979. 22. Pess GR, Montgomery DR, Steel EA, Bilby RE, Feist BE, et al. (2002) Landscape characteristics, land use, and coho salmon (Oncorhynchus kisutch) abundance, Snohomish River, Wash., USA. Canadian Journal of Fisheries and Aquatic Sciences 59: 613–623. 23. Alberti M, Weeks R, Coe S (2004) Urban land-cover change analysis in Central Puget Sound. Photogrammetric Engineering and Remote Sensing 70: 1043–1052. 24. Alberti M, Weeks R, Hepsintall J, Russell C, Coe S, et al. (2004) Puget Sound Regional Synthesis Model: 2002 Land-cover Analysis of the Greater Puget Sound Region. Seattle, WA: University of Washington. 26 p. 25. Homer C, Huang C, Yang L, Wylie B, Coan M (2004) Development of a 2001 National Landcover Database for the United States. Photogrammetric Engineering and Remote Sensing 70: 829–840. 26. King County (2000) King County Tax Parcels. CD-ROM. Seattle, WA: King County. 27. Kitsap County (2010) Land Information System (LIS): Tax Parcels. Figure 3. Predictive map of modeled coho spawner mortality rates within the Puget Sound lowlands.Mortality rates are a function of the proportion of key landscape variables within a given basin. Green, yellow and red areas indicate basins with predicted rates of spawner mortality (as a percentage of total fall runs) of ,10%, 10–50%, and .50%, respectively. Black dots denote locations of the six study sites that were the basis for this analysis. Thick dashed black line depicts the southern boundary of the coho salmon Puget Sound/Georgia Basin Evolutionarily Significant Unit (ESU). Basins that do not have documented presence of coho salmon [38] are not represented on the map, even if they have landscape conditions associated with coho spawner mortality. Key for site numbers: 1=Des Moines; 2=Fauntleroy; 3=Fortson; 4=Longfellow; 5=Piper’s; and, 6=Thornton Creek. doi:10.1371/journal.pone.0023424.g003 Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 10 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 72 of 291 28. Pierce County (2008) Tax Parcels. Tacoma, WA: Pierce County Assessor- Treasurer. 29. Snohomish County (2010) Parcels Snohomish County Assessor. 30. Puget Sound Regional Council (2005) Road centerlines and widths. Available: http://www.psrc.org. Accessed: 2005 Aug 16. 31. Federal Highway Administration (1989) Functional Classification Guidelines U.S. Department of Transportation. 34 p. 32. Bolker BM, Brooks ME, Clark CJ, Geange SW, Poulsen JR, et al. (2009) Generalized linear mixed models: a practical guide for ecology and evolution. Trends in Ecology & Evolution 24: 127–135. 33. Gelman A, Hill J (2007) Data analysis using regression and multilevel/ hierarchical models. New York, NY: Cambridge University Press. 648 p. 34. Pinheiro JC, Bates DM (2001) Mixed-effects models in S and S-PLUS; Chambers J, Eddy W, Hardle W, Sheather S, Tierney L, eds. New York, NY: Springer Verlag. 528 p. 35. R Development Core Team (2010) R: A language and environment for statistical computing. 2.12.0 ed. Vienna, Austria: The R Development Core Team. 36. Burnham KP, Anderson DR (2002) Model selection and multimodel inference: A practical information theoretic approach. New York, NY: Springer-Verlag. 488 p. 37. U.S. Environmental Protection Agency, U.S. Geological Survey (2005) National Hydrography Dataset Plus – NHDPlus. Available: http://www.horizon-systems. com/NHDPlus/HSC-wth17.php. Accessed: 2010 May 26. 38. Washington Department of Fish and Wildlife (2011) 1:24,000 Fish Distribution of Washington State: Washington Lakes and Rivers Information System (WLRIS) - fishdist. February 2011 ed. Olympia, WA: Washington Department of Fish and Wildlife. 39. Karr JR (1991) Biological Integrity: A Long-Neglected Aspect of Water Resource Management. Ecological Applications 1: 66–84. 40. Alberti M, Booth D, Hill K, Coburn B, Avolio C, et al. (2007) The impact of urban patterns on aquatic ecosystems: An empirical analysis in Puget lowland sub-basins. Landscape and Urban Planning 80: 345–361. 41. Wenger SJ, Roy AH, Jackson CR, Bernhardt ES, Carter TL, et al. (2009) Twenty-six key research questions in urban stream ecology: an assessment of the state of the science. Journal of the North American Benthological Society 28: 1080–1098. 42. Morley SA, Karr JR (2002) Assessing and restoring the health of urban streams in the Puget Sound basin. Conservation Biology 16: 1498–1509. 43. Bilby RE, Mollot LA (2008) Effect of changing land use patterns on the distribution of coho salmon (Oncorhynchus kisutch) in the Puget Sound region. Canadian Journal of Fisheries and Aquatic Sciences 65: 2138–2148. 44. Feist BE, Steel EA, Jensen DW, Sather DND (2010) Does the scale of our observational window affect our conclusions about correlations between endangered salmon populations and their habitat? Landscape Ecology 25: 727–743. 45. Committee on Protection and Management of Pacific Northwest Anadromous Salmonids, National Research Council (1996) Habitat Management and Rehabilitation. Upstream: Salmon and Society in the Pacific Northwest. Washington, DC: National Academy Press. pp 204–225. 46. Katz SL, Barnas K, Hicks R, Cowen J, Jenkinson R (2007) Freshwater Habitat Restoration Actions in the Pacific Northwest: A Decade’s Investment in Habitat Improvement. Restoration Ecology 15: 494–505. 47. Niyogi S, Wood CM (2004) Biotic Ligand Model, a Flexible Tool for Developing Site-Specific Water Quality Guidelines for Metals. Environmental Science & Technology 38: 6177–6192. 48. Hoffman EJ, Latimer JS, Mills GL, Quinn JG (1982) Petroleum hydrocarbons in urban runoff from a commercial land use area. Journal Water Pollution Control Federation 54: 1517–1525. 49. Whipple W, Hunter JV (1979) Petroleum hydrocarbons in urban runoff. Journal of the American Water Resources Association 15: 1096–1105. 50. Claireaux G, Davoodi F (2010) Effect of exposure to petroleum hydrocarbons upon cardio-respiratory function in the common sole (Solea solea). Aquatic Toxicology 98: 113–119. 51. McMillan B (2007) The Spawning Survey Findings from Seattle’s Thornton, Piper’s, Longfellow, Fauntleroy and Taylor Creeks, September 21, 2006 to January 24, 2007. Also including the cumulative spawning survey data from 1999–2006 and Des Moines Creek in 2003 and 2004. Seattle, Washington, USA: Seattle Public Utilities. 52. Wild Fish Conservancy (2008) Spawning Survey Findings from Seattle’s Thornton, Piper’s, Longfellow, Fauntleroy and Taylor Creeks. Seattle, Washington, USA: Seattle Public Utilities. Ecotoxicology of Salmon Mortality in Urban Streams PLoS ONE | www.plosone.org 11 August 2011 | Volume 6 | Issue 8 | e23424 EXHIBIT 5 73 of 291 0 0.55 1.1 1.65 2.20.275 mi Not a barrier Partial FishPassageBlockage Total FishPassageBlockageBarrier,UnknownPercentPassable Diversion Natural Barrier -Verified Unknown CorrectedBarriers Fish Distribution Exported: 8/28/2019 10:43:40 AM Washington State Fish Passage Mullen Slough http://apps.wdfw.wa.gov/fishpassage/?extent=-122.3400,47.3173,-122.1661,47.3888 EXHIBIT 5 74 of 291 From: Evan Mann <evan@soundbuilthomes.com> Sent: Wednesday, September 11, 2019 10:33 AM To: Thaniel Gouk Cc: Steven Sturza; Sheri H. Murata; JEFFERY Jones; Kurt Wilson Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance Attachments: West Hill Crit Area Addendum 9 6 2019 Compl.pdf CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Good morning Thaniel, Please see attached the addendum from our biologist addressing the concerns of the Muckleshoot Indian Tribe. I have added some notes below in red as well. Evan Mann Entitlement Manager SoundBuilt Homes 253.820.7835 evan@soundbuilthomes.com From: Thaniel Gouk Sent: Thursday, August 29, 2019 7:52 AM To: Evan Mann Cc: Steven Sturza Subject: FW: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance Importance: High Evan – please see below comments from the MIT, I will need a response from your consultant. Depending on his response we will cater our response to the stormwater question posed. Thanks, Thaniel From: Karen Walter <KWalter@muckleshoot.nsn.us> Sent: Wednesday, August 28, 2019 11:12 AM To: Thaniel Gouk <tgouk@auburnwa.gov> Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance EXHIBIT 5 75 of 291 CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Thaniel, We have reviewed the SEPA documents and other available information for the proposed West Hill 19- lot plat at 29255 and 29242 59th Ave S in Auburn, We offer the following comments in the interest of protecting and restoring the Tribe’s treaty-protected fisheries resources: 1. Stream classification The checklist may be incorrect regarding the stream classification of Mullens Slough tributaries found both on and adjacent to the project site. According to WDFW’s Salmonscape map, there is documented coho presence throughout the entire stream. (See attached map). This information was neither identified nor considered in the project materials. This information was included in the first 2 versions of the critical area report but for some reason was not included in the 3rd and final report. This was an error and was not intentional. As such Jeff Jones, the wetland biologist, has prepared an addendum to address the stream and any fish-bearing potential. His findings are consistent with his earlier reports stating that there are significant gradients downstream of this site that are considered natural fish passage barriers. As such, the stream is not fish-bearing and the buffer as shown on the plans is accurate. Further, there are no documented natural or artificial barriers currently identified in Mullen Slough or its tributaries downstream of the site. WDFW’s information may not be fully complete. If Auburn has data to suggest otherwise, we request a copy of this information. The culvert on 59th Avenue that conveys the Mullens Slough tributary may be a fish passage barrier based on its size (24”) versus the stream bankfull of 2-4 feet in width. The slope of culvert is unknown but it, too, may a factor in the barrier condition of this culvert. The culvert is not a factor in fish passage that we are accounting for. The slopes are the natural barrier. Auburn needs to treat this tributary of Mullens Slough as a fish-bearing water in absence of information otherwise. If there is data to suggest otherwise, we request a copy and the opportunity to review it and provide further comments as needed. 2. Project impacts The project currently does not comply with mitigation sequencing requirements. The Critical Areas Report starts with the proposal to reduce wetland (and arguably stream buffers) without any explanation as to purpose and need and how mitigation sequencing was met which is contrary to State SEPA requirements. There is no analysis or demonstration that this project needs to impact the existing stream and wetland buffers as proposed. Avoidance is the first step in mitigation sequencing. There is no information about how this project is minimizing its impacts. Finally, there is no analysis to demonstrate that the full impacts of the proposed buffer reductions affects stream and wetland functions (including a tree inventory to determine EXHIBIT 5 76 of 291 riparian functional losses). Finally, there is no analysis to demonstrate that the proposed mitigation adequately offsets these impacts and ensures a no net loss of wetland or stream functions. The project as designed is not proposing wetland or stream buffer reductions or averaging. The 25’ buffers are being respected and preserved. As such, a discussion of mitigation sequencing is not required. Also, with respect to the proposed stormwater treatment method, the project should be providing enhanced treatment since this project will discharge its stormwater to Mullens Slough tributaries that have known salmon use. Salmon can be adversely affected by oils and heavy metals in stormwater; therefore, the project needs to maximize treatment to minimize the project’s potential impacts from stormwater discharges. Some of the available scientific data and literature is in the attached papers. There is substantial more information on this topic available online. Stormwater treatment for this site is proposed to meet the City of Auburn and DOE engineering and stormwater standards. These standards have been deemed sufficient to protect natural features from water quality issues. The stormwater from this site will be treated using Modular Wetlands and a Storm Vault and then released into an existing stormwater conveyance. We appreciate the opportunity to review this proposal and look forward to the City/applicants’ written responses to these concerns. We may have further comments subsequently. Thank you, Karen Walter Watersheds and Land Use Team Leader Muckleshoot Indian Tribe Fisheries Division Habitat Program 39015-A 172nd Ave SE Auburn, WA 98092 253-876-3116 From: Thaniel Gouk [mailto:tgouk@auburnwa.gov] Sent: Wednesday, August 14, 2019 11:53 AM To: 'cblansfield@auburn.wednet.edu'; 'brian.davis@cityoffederalway.com'; 'paan461@ecy.wa.gov'; 'sepaunit@ecy.wa.gov'; 'MARI461@ECY.WA.GOV'; 'sepacenter@dnr.wa.gov'; 'jim.chan@kingcounty.gov'; 'hubenbj@dshs.wa.gov'; 'tosborne@lakehaven.org'; 'kbush@mbaks.com'; Karen Walter; 'shirlee.tan@kingcounty.gov'; 'cmoore@fwps.org'; 'tim@futurewise.org'; 'Valerie.Garza@kingcounty.gov'; 'Planning@KentWA.gov'; 'josh.baldi@kingcounty.gov'; 'Steve.Bleifuhs@kingcounty.gov'; 'beth.humphreys@kingcounty.gov'; 'laila.mcclinton@kingcounty.gov'; 'pazookr@wsdot.wa.gov'; 'maint.roads@kingcounty.gov'; 'jgreene@kingcounty.gov'; Jeffrey Watson; Krongthip Sangkapreecha; Rob Otsea; Laura Murphy; 'sepa@dahp.wa.gov'; 'gretchen.kaehler@dahp.wa.gov'; 'jeff.payne@pse.com'; 'James.H.Carsner@usace.army.mil'; 'SEPA@pscleanair.org'; 'perry.weinberg@soundtransit.org'; 'rob.ryan@wa.usda.gov'; Karen Stewart VRFA; 'reviewteam@commerce.wa.gov'; 'Larry.Fisher@dfw.wa.gov'; 'mindy@wecprotects.org'; 'SEPA.reviewteam@doh.wa.gov' EXHIBIT 5 77 of 291 Cc: Planning-1 Subject: SEP18-0017 - Soundbuilt Homes 19-Lot Preliminary Plat Please see the attached SEPA DNS and associated SEPA Checklist. Please submit any comments by August 29, 2019. More information is available on the City’s website at www.auburnwa.gov/landuse. Thanks, Thaniel Gouk – Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov 253.804.5031 | tgouk@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 Customer Service Survey Application Forms Zoning Maps This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. EXHIBIT 5 78 of 291 King County Date: 9/6/2019 Notes: ±The information included on this map has been compiled by King County staff from a variety of sources and issubject to change without notice. King County makes no representations or warranties, express or implied,as to accuracy, completeness, timeliness, or rights to the use of such information. This document is not intendedfor use as a survey product. King County shall not be liable for any general, special, indirect, incidental, orconsequential damages including, but not limited to, lost revenues or lost profits resulting from the use or misuseof the information contained on this map. Any sale of this map or information on this map is prohibited except bywritten permission of King County. Mullens CreekEXHIBIT 5 79 of 291 1 Addendum to the Critical Area Study West Hills Plat 29241 & 29255 59th Ave. S. Auburn, Washington Tax Parcel Numbers: 022104-9044 & 9071 Southwest 1/4 of Section 2, Township 21 N, Range 4 E of the Willamette Meridian Prepared for: Sound Built Development P.O. Box 73790 Puyallup, WA 98371 Evan Mann Entitlement Manager SoundBuilt Homes 253.820.7835 evan@soundbuilthomes.com Dated: September 6, 2019 Prepared by: Jeffery S. Jones, Wetland Scientist & Wildlife Biologist EXHIBIT 5 80 of 291 Project Description The applicant proposes to plat the subject parcels into single-family lots. A Critical Area Study was conducted to determine the type and extent of wetlands and streams on and near the site. Stream Classification Karen Walter, Muckleshoot Fisheries Biologist, reviewed the SEPA checklist and provided comments. Her first comment was regarding the stream classification of Mullens Creek. The Salmonscape mapping, provided by Karen Walter, identifies all the Mullens Creek tributaries as having documented fish presence. However, there is no information about sampling or observations that document fish presence above the valley floor. About fifteen years ago, I walked the subject tributary upstream from the Litowitz property on S. 287th St. Above the valley floor, the stream channel gradient is 20-30%, with at least several sections exceeding 30%. The sections exceeding 30% are natural barriers to fish passage. There is over 1,200 feet of continuously steep gradient. Larry Fisher, the regional WDFW biologist, has been contacted to find out what he knows about fish presence in the subject stream. However, he has not replied as of the date of this report. It is extremely unlikely that coho are present in Mullens Creek at the subject site. The natural stream channel gradient downstream has sections that exceed a 30% gradient, which is are too steep for fish passage. Artificial barriers such as the culvert at 59th Ave. S. can be replaced with fish passage culverts and therefore are not used to make a determination of no fish presence. Project Impacts A critical area impact analysis will be prepared that addresses the code requirements for mitigation sequencing and a net effect on wetland and stream functions. It is our belief that the stream and wetland functions will increase with buffer enhancement, because the existing buffer is dominated by invasive plants. A tree inventory will be included in the impact analysis. Stormwater treatment will be addressed by the civil engineer. EXHIBIT 5 81 of 291 From: Karen Walter <KWalter@muckleshoot.nsn.us> Sent: Thursday, September 12, 2019 4:17 PM To: Thaniel Gouk Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance Follow Up Flag: Follow up Flag Status: Completed CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Thaniel, Thank you for getting back to us on this project. A couple of follow-ups: Mullen Slough stream typing The applicant notes a revised Critical Areas Report but did not include it. Please send us a copy. We also request the applicant’s consultants data regarding the streambed gradients, the extent of gradients that exceed 20% and the distance this is exceeded. To be considered a natural barrier, the consultant should be using WDFW’s natural barrier assessment method in the Fish Barrier Assessment Manual and the corresponding data sheets that are described in that manual. https://wdfw.wa.gov/publications/02061 Complete documentation of a downstream natural barrier is needed to demonstrate that there is no potential fish habitat on/near and upstream of this property. Stormwater comments The stormwater comments we raised is not sufficiently addressed with the responses. Best, Karen Walter Watersheds and Land Use Team Leader Muckleshoot Indian Tribe Fisheries Division Habitat Program 39015-A 172nd Ave SE Auburn, WA 98092 253-876-3116 From: Thaniel Gouk [mailto:tgouk@auburnwa.gov] Sent: Thursday, September 12, 2019 3:21 PM To: Karen Walter Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance EXHIBIT 5 82 of 291 Good afternoon Karen. The Applicant has provided a response to your comments below, please see attached. Let me know if you have any other comments or concerns with this response. Thanks, Thaniel From: Karen Walter <KWalter@muckleshoot.nsn.us> Sent: Wednesday, August 28, 2019 11:12 AM To: Thaniel Gouk <tgouk@auburnwa.gov> Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Thaniel, We have reviewed the SEPA documents and other available information for the proposed West Hill 19-lot plat at 29255 and 29242 59th Ave S in Auburn, We offer the following comments in the interest of protecting and restoring the Tribe’s treaty-protected fisheries resources: 1. Stream classification The checklist may be incorrect regarding the stream classification of Mullens Slough tributaries found both on and adjacent to the project site. According to WDFW’s Salmonscape map, there is documented coho presence throughout the entire stream. (See attached map). This information was neither identified nor considered in the project materials. Further, there are no documented natural or artificial barriers currently identified in Mullen Slough or its tributaries downstream of the site. WDFW’s information may not be fully complete. If Auburn has data to suggest otherwise, we request a copy of this information. The culvert on 59th Avenue that conveys the Mullens Slough tributary may be a fish passage barrier based on its size (24”) versus the stream bankfull of 2-4 feet in width. The slope of culvert is unknown but it, too, may a factor in the barrier condition of this culvert. Auburn needs to treat this tributary of Mullens Slough as a fish-bearing water in absence of information otherwise. If there is data to suggest otherwise, we request a copy and the opportunity to review it and provide further comments as needed. 2. Project impacts The project currently does not comply with mitigation sequencing requirements. The Critical Areas Report starts with the proposal to reduce wetland (and arguably stream buffers) without any explanation as to purpose and need and how mitigation sequencing was met which is contrary to State SEPA requirements. There is no analysis or demonstration that this project needs to impact the existing stream and wetland buffers as proposed. Avoidance is the first step EXHIBIT 5 83 of 291 in mitigation sequencing. There is no information about how this project is minimizing its impacts. Finally, there is no analysis to demonstrate that the full impacts of the proposed buffer reductions affects stream and wetland functions (including a tree inventory to determine riparian functional losses). Finally, there is no analysis to demonstrate that the proposed mitigation adequately offsets these impacts and ensures a no net loss of wetland or stream functions. Also, with respect to the proposed stormwater treatment method, the project should be providing enhanced treatment since this project will discharge its stormwater to Mullens Slough tributaries that have known salmon use. Salmon can be adversely affected by oils and heavy metals in stormwater; therefore, the project needs to maximize treatment to minimize the project’s potential impacts from stormwater discharges. Some of the available scientific data and literature is in the attached papers. There is substantial more information on this topic available online. We appreciate the opportunity to review this proposal and look forward to the City/applicants’ written responses to these concerns. We may have further comments subsequently. Thank you, Karen Walter Watersheds and Land Use Team Leader Muckleshoot Indian Tribe Fisheries Division Habitat Program 39015-A 172nd Ave SE Auburn, WA 98092 253-876-3116 From: Thaniel Gouk [mailto:tgouk@auburnwa.gov] Sent: Wednesday, August 14, 2019 11:53 AM To: 'cblansfield@auburn.wednet.edu'; 'brian.davis@cityoffederalway.com'; 'paan461@ecy.wa.gov'; 'sepaunit@ecy.wa.gov'; 'MARI461@ECY.WA.GOV'; 'sepacenter@dnr.wa.gov'; 'jim.chan@kingcounty.gov'; 'hubenbj@dshs.wa.gov'; 'tosborne@lakehaven.org'; 'kbush@mbaks.com'; Karen Walter; 'shirlee.tan@kingcounty.gov'; 'cmoore@fwps.org'; 'tim@futurewise.org'; 'Valerie.Garza@kingcounty.gov'; 'Planning@KentWA.gov'; 'josh.baldi@kingcounty.gov'; 'Steve.Bleifuhs@kingcounty.gov'; 'beth.humphreys@kingcounty.gov'; 'laila.mcclinton@kingcounty.gov'; 'pazookr@wsdot.wa.gov'; 'maint.roads@kingcounty.gov'; 'jgreene@kingcounty.gov'; Jeffrey Watson; Krongthip Sangkapreecha; Rob Otsea; Laura Murphy; 'sepa@dahp.wa.gov'; 'gretchen.kaehler@dahp.wa.gov'; 'jeff.payne@pse.com'; 'James.H.Carsner@usace.army.mil'; 'SEPA@pscleanair.org'; 'perry.weinberg@soundtransit.org'; 'rob.ryan@wa.usda.gov'; Karen Stewart VRFA; 'reviewteam@commerce.wa.gov'; 'Larry.Fisher@dfw.wa.gov'; 'mindy@wecprotects.org'; 'SEPA.reviewteam@doh.wa.gov' Cc: Planning-1 Subject: SEP18-0017 - Soundbuilt Homes 19-Lot Preliminary Plat Please see the attached SEPA DNS and associated SEPA Checklist. Please submit any comments by August 29, 2019. More information is available on the City’s website at www.auburnwa.gov/landuse. Thanks, Thaniel Gouk – Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov EXHIBIT 5 84 of 291 253.804.5031 | tgouk@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 Customer Service Survey Application Forms Zoning Maps This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. EXHIBIT 5 85 of 291 From: Shannon Howard Sent: Tuesday, September 17, 2019 2:42 PM To: 'Karen Walter' Cc: Development; Thaniel Gouk; Dustin Lawrence Subject: FW: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance Attachments: FW: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance; West Hill Downstream Gradient Exhibit.pdf Hi Karen- We received this response from Soundbuilt Homes regarding your comments on the West Hill Plat (SEP18-0017/PLT18-0004). Thaniel is out of the office until later this week, but I wanted to get them over to you as soon as possible. Please let me know if you have any questions. Thanks Shannon Shannon Howard, PE CFM Development Review Engineer Department of Community Development City of Auburn | www.auburnwa.gov Phone: (253) 804-5073 | showard@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Map) Customer Service Survey | Application Forms | Zoning Maps From: Evan Mann <evan@soundbuilthomes.com> Sent: Monday, September 16, 2019 5:09 PM To: Shannon Howard <showard@auburnwa.gov> Cc: Sheri H. Murata <shm@coredesigninc.com>; JEFFERY Jones <jeff.jsjones@comcast.net>; Kurt Wilson <kurt@soundbuilthomes.com>; Steven Sturza <ssturza@auburnwa.gov>; Thaniel Gouk <tgouk@auburnwa.gov> Subject: FW: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance EXHIBIT 5 86 of 291 CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Hi Shannon, I understand that while Thaniel is out of the office you will be managing this issue for the West Hill plat. Please see the response highlighted below from our wetland biologist Jeffrey Jones. This is in response to the attached email from Thaniel in which he forwarded additional comment from Karen Walter. The natural fish barrier is a known element in this area and was confirmed by WDFW below. No additional documentation should be necessary. The latest critical area report dated 9/13/18 (which the city has in the record) in conjunction with the addendum dated 9/6/19 that was provided on 9/11/19 via email should constitute a complete and satisfactory record to address critical areas. We have also prepared the attached West Hill Downstream Gradient Exhibit that shows the gradient barrier per the WDFW Fish Passage Inventory, Assessment, and Prioritization Manual. In order for the gradient to qualify as a natural fish passage barrier the manual states: “For a stream reach to be considered a gradient barrier, a water surface slope of 20% or greater should be sustained for a minimum length of 160 meters.” Per the attached exhibit the stream drops ±145 vertical feet over the distance of ±525 (160 meters) linear feet for a total gradient of 27.62%. This slope is consistent and constant along that stretch of the stream and is without resting areas for fish. This further confirms what Larry Fischer at WDFW and Jeffrey Jones have indicated. With regard to stormwater treatment, we will meet the necessary City of Auburn and DOE standards as they relate to water quality and cannot be required to do more when there are no proposed impacts as demonstrated in the stormwater report provided with our application. We expect this information is sufficient to proceed with the preparation of the necessary staff report conditions and the hearing scheduled in October. Thank you, Evan Mann Entitlement Manager SoundBuilt Homes 253.820.7835 evan@soundbuilthomes.com From: JEFFERY Jones <jeff.jsjones@comcast.net> Sent: Monday, September 16, 2019 2:19 PM To: Thaniel Gouk <tgouk@auburnwa.gov>; Evan Mann <evan@soundbuilthomes.com> Cc: Steven Sturza <ssturza@auburnwa.gov>; Sheri H. Murata <shm@coredesigninc.com>; Kurt Wilson <kurt@soundbuilthomes.com> Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance EXHIBIT 5 87 of 291 Thaniel, I had a phone conservation with the WDFW fisheries biologist for the Auburn area and he confirmed there are no fish use in streams with a 28% gradient which is the downstream gradient of the subject stream. The section with a 28% gradient is 1,200 feet long in a narrow steeply sided drainage pattern. WDFW considers streams above a 16% gradient non-fish bearing. The WDFW biologist is Larry Fischer. Jeff Jones On September 12, 2019 at 3:00 PM Thaniel Gouk <tgouk@auburnwa.gov> wrote: Received, thanks. -Thaniel From: Evan Mann <evan@soundbuilthomes.com> Sent: Wednesday, September 11, 2019 10:33 AM To: Thaniel Gouk <tgouk@auburnwa.gov> Cc: Steven Sturza <ssturza@auburnwa.gov>; Sheri H. Murata <shm@coredesigninc.com>; JEFFERY Jones <jeff.jsjones@comcast.net>; Kurt Wilson <kurt@soundbuilthomes.com> Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments Good morning Thaniel, Please see attached the addendum from our biologist addressing the concerns of the Muckleshoot Indian Tribe. I have added some notes below in red as well. EXHIBIT 5 88 of 291 Evan Mann Entitlement Manager SoundBuilt Homes 253.820.7835 evan@soundbuilthomes.com From: Thaniel Gouk <tgouk@auburnwa.gov> Sent: Thursday, August 29, 2019 7:52 AM To: Evan Mann <evan@soundbuilthomes.com> Cc: Steven Sturza <ssturza@auburnwa.gov> Subject: FW: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance Importance: High Evan – please see below comments from the MIT, I will need a response from your consultant. Depending on his response we will cater our response to the stormwater question posed. Thanks, Thaniel From: Karen Walter <KWalter@muckleshoot.nsn.us> Sent: Wednesday, August 28, 2019 11:12 AM To: Thaniel Gouk <tgouk@auburnwa.gov> Subject: RE: SEP18-0017/PLT18-0004 - Soundbuilt Homes, West Hill 19-Lot Preliminary Plat, Determination of Non-Significance CAUTION: The following message originated from outside the City of Auburn. Be careful opening links and attachments EXHIBIT 5 89 of 291 Thaniel, We have reviewed the SEPA documents and other available information for the proposed West Hill 19-lot plat at 29255 and 29242 59th Ave S in Auburn, We offer the following comments in the interest of protecting and restoring the Tribe’s treaty-protected fisheries resources: 1. Stream classification The checklist may be incorrect regarding the stream classification of Mullens Slough tributaries found both on and adjacent to the project site. According to WDFW’s Salmonscape map, there is documented coho presence throughout the entire stream. (See attached map). This information was neither identified nor considered in the project materials. This information was included in the first 2 versions of the critical area report but for some reason was not included in the 3rd and final report. This was an error and was not intentional. As such Jeff Jones, the wetland biologist, has prepared an addendum to address the stream and any fish-bearing potential. His findings are consistent with his earlier reports stating that there are significant gradients downstream of this site that are considered natural fish passage barriers. As such, the stream is not fish-bearing and the buffer as shown on the plans is accurate. Further, there are no documented natural or artificial barriers currently identified in Mullen Slough or its tributaries downstream of the site. WDFW’s information may not be fully complete. If Auburn has data to suggest otherwise, we request a copy of this information. The culvert on 59th Avenue that conveys the Mullens Slough tributary may be a fish passage barrier based on its size (24”) versus the stream bankfull of 2-4 feet in width. The slope of culvert is unknown but it, too, may a factor in the barrier condition of this culvert. The culvert is not a factor in fish passage that we are accounting for. The slopes are the natural barrier. Auburn needs to treat this tributary of Mullens Slough as a fish-bearing water in absence of information otherwise. If there is data to suggest otherwise, we request a copy and the opportunity to review it and provide further comments as needed. 2. Project impacts The project currently does not comply with mitigation sequencing requirements. The Critical Areas Report starts with the proposal to reduce wetland (and arguably stream buffers) without any explanation as to purpose and need and how mitigation sequencing EXHIBIT 5 90 of 291 was met which is contrary to State SEPA requirements. There is no analysis or demonstration that this project needs to impact the existing stream and wetland buffers as proposed. Avoidance is the first step in mitigation sequencing. There is no information about how this project is minimizing its impacts. Finally, there is no analysis to demonstrate that the full impacts of the proposed buffer reductions affects stream and wetland functions (including a tree inventory to determine riparian functional losses). Finally, there is no analysis to demonstrate that the proposed mitigation adequately offsets these impacts and ensures a no net loss of wetland or stream functions. The project as designed is not proposing wetland or stream buffer reductions or averaging. The 25’ buffers are being respected and preserved. As such, a discussion of mitigation sequencing is not required. Also, with respect to the proposed stormwater treatment method, the project should be providing enhanced treatment since this project will discharge its stormwater to Mullens Slough tributaries that have known salmon use. Salmon can be adversely affected by oils and heavy metals in stormwater; therefore, the project needs to maximize treatment to minimize the project’s potential impacts from stormwater discharges. Some of the available scientific data and literature is in the attached papers. There is substantial more information on this topic available online. Stormwater treatment for this site is proposed to meet the City of Auburn and DOE engineering and stormwater standards. These standards have been deemed sufficient to protect natural features from water quality issues. The stormwater from this site will be treated using Modular Wetlands and a Storm Vault and then released into an existing stormwater conveyance. We appreciate the opportunity to review this proposal and look forward to the City/applicants’ written responses to these concerns. We may have further comments subsequently. Thank you, Karen Walter Watersheds and Land Use Team Leader Muckleshoot Indian Tribe Fisheries Division Habitat Program 39015-A 172nd Ave SE Auburn, WA 98092 253-876-3116 EXHIBIT 5 91 of 291 From: Thaniel Gouk [mailto:tgouk@auburnwa.gov] Sent: Wednesday, August 14, 2019 11:53 AM To: 'cblansfield@auburn.wednet.edu'; 'brian.davis@cityoffederalway.com'; 'paan461@ecy.wa.gov'; 'sepaunit@ecy.wa.gov'; 'MARI461@ECY.WA.GOV'; 'sepacenter@dnr.wa.gov'; 'jim.chan@kingcounty.gov'; 'hubenbj@dshs.wa.gov'; 'tosborne@lakehaven.org'; 'kbush@mbaks.com'; Karen Walter; 'shirlee.tan@kingcounty.gov'; 'cmoore@fwps.org'; 'tim@futurewise.org'; 'Valerie.Garza@kingcounty.gov'; 'Planning@KentWA.gov'; 'josh.baldi@kingcounty.gov'; 'Steve.Bleifuhs@kingcounty.gov'; 'beth.humphreys@kingcounty.gov'; 'laila.mcclinton@kingcounty.gov'; 'pazookr@wsdot.wa.gov'; 'maint.roads@kingcounty.gov'; 'jgreene@kingcounty.gov'; Jeffrey Watson; Krongthip Sangkapreecha; Rob Otsea; Laura Murphy; 'sepa@dahp.wa.gov'; 'gretchen.kaehler@dahp.wa.gov'; 'jeff.payne@pse.com'; 'James.H.Carsner@usace.army.mil'; 'SEPA@pscleanair.org'; 'perry.weinberg@soundtransit.org'; 'rob.ryan@wa.usda.gov'; Karen Stewart VRFA; 'reviewteam@commerce.wa.gov'; 'Larry.Fisher@dfw.wa.gov'; 'mindy@wecprotects.org'; 'SEPA.reviewteam@doh.wa.gov' Cc: Planning-1 Subject: SEP18-0017 - Soundbuilt Homes 19-Lot Preliminary Plat Please see the attached SEPA DNS and associated SEPA Checklist. Please submit any comments by August 29, 2019. More information is available on the City’s website at www.auburnwa.gov/landuse. Thanks, Thaniel Gouk – Senior Planner Department of Community Development City of Auburn | www.auburnwa.gov 253.804.5031 | tgouk@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 EXHIBIT 5 92 of 291 Permit Center Address: 1 E Main Street, Auburn, WA 98002 Customer Service Survey Application Forms Zoning Maps This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. EXHIBIT 5 93 of 291 King County West Hill Downstream Gradient Exhibit Date: 9/16/2019 Notes:±The information included on this map has been compiled by King County staff from a variety of sources and is subject to change without notice. King Countymakes no representations or warranties, express or implied, as to accuracy, completeness, timeliness, or rights to the use of such information. This document isnot intended for use as a survey product. King County shall not be liable for any general, special, indirect, incidental, or consequential damages including,but not limited to, lost revenues or lost profits resulting from the use or misuse of the information contained on this map. Any sale of this map or information onthis map is prohibited except by written permission of King County. 525+ (>160 meters) linear feet at ±27% gradient equates to a natural barrier to fish passage. SITE EXHIBIT 5 94 of 291 STATE OF WASHINGTON DEPARTMENT OF ECOLOGY Northwest Regional Office  3190 160th Avenue SE  Bellevue, Washington 98008-5452  (425) 649-7000 711 for Washington Relay Service  Persons with a speech disability can call (877) 833-6341 August 28, 2019 Thaniel Gouk Planning & Development City of Auburn 25 West Main St Auburn, WA 98001 Re: West Hill Preliminary Plat File# SEP18-0017/PLT18-0004, Ecology SEPA# 201904664 Dear Thaniel Gouk: Thank you for the opportunity to provide comments on the West Hill Preliminary Plat. Based on review of the State Environmental Policy Act (SEPA) checklist associated with this Project, the Department of Ecology (Ecology) has the following comments: This proposed project is located in an area that may have been contaminated with heavy metals due to the air emissions originating from the old Asarco smelter in north Tacoma (visit Ecology’s Tacoma Smelter Plume map search tool: https://fortress.wa.gov/ecy/dirtalert/). Soil contamination from the former Asarco smelter poses a risk to human health and the environment. Children are at especially high risk from direct exposure to contaminated soil. Construction workers, landscapers, gardeners, and others who work in the soils are also at risk. Ecology recommends that the lead agency include the following as conditions of approval, prior to the issuance of any site development permits or the initiation of grading, filling, or clearing:  Sample the soil and analyze for arsenic and lead following the 2012 Tacoma Smelter Plume Guidance. The soil sampling results shall be sent to Ecology for review. If the project includes open space areas, contact the Technical Assistance Coordinator, Eva Barber, for assistance in soil sampling methodology within the open space area.  If lead or arsenic are found at concentrations above the Model Toxics Control Act (MTCA) cleanup levels (Chapter 173-340 WAC); the owners, potential buyers, construction workers, and others shall be notified of their occurrence. The MTCA cleanup level for arsenic is 20 parts per million (ppm) and lead is 250 ppm. EXHIBIT 5 95 of 291 Thaniel Gouk August 28, 2019 Page 2  If lead, arsenic and/or other contaminants are found at concentrations above MTCA cleanup levels, the applicant shall: 1. Develop soil remediation plan and enter into the Voluntary Cleanup Program with Ecology. For more information on the Voluntary Cleanup Program, visit Ecology website at: https://ecology.wa.gov/Spills-Cleanup/Contamination-cleanup/Cleanup- process/Cleanup-options/Voluntary-cleanup-program. 2. Obtain an opinion letter from Ecology stating that the proposed soil remediation plan will likely result in no further action under MTCA. The applicant shall provide to the local land use permitting agency the opinion letter from Ecology. 3. Prior to finalizing site development permits, provide to the local land use permitting agency “No Further Action” determination from Ecology indicating that the remediation plans were successfully implemented under MTCA.  If soils are found to be contaminated with arsenic, lead, or other contaminants, extra precautions shall be taken to avoid escaping dust, soil erosion, and water pollution during grading and site construction. Site design shall include protective measures to isolate or remove contaminated soils from public spaces, yards, and children’s play areas. Contaminated soils generated during site construction shall be managed and disposed of in accordance with state and local regulations, including the Solid Waste Handling Standards regulation (Chapter 173-350 WAC). For information about soil disposal contact the local health department in the jurisdiction where soils will be placed. The link below provides a fact sheet that explains more how the arsenic and lead clean-up levels were set and why Ecology sees that they are protective for human health: https://fortress.wa.gov/ecy/publications/SummaryPages/1109095.html Thank you for considering these comments from Ecology. For assistance and information about Tacoma Smelter Plume and soils contamination, contact Eva Barber with the Toxic Cleanup Program at 360-407-7094 or via email at Eva.Barber@ecy.wa.gov. Sincerely, Katelynn Piazza SEPA Coordinator Sent by email: Thaniel Gouk, planning@auburnwa.gov cc: Evan Mann, Soundbuilt Homes ecc: Eva Barber, Ecology EXHIBIT 5 96 of 291 DESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10 HORIZONTAL DATUM / BASIS OF BEARINGS VERTICAL DATUM BENCHMARK REFERENCES LEGAL DESCRIPTION VICINITY MAP APPLICANT PLANNER/LANDSCAPE ENGINEER/SURVEYOR SHEET INDEXSITE STATISTICS COVER SHEETP1 WATER/SEWER PROVIDER SCHOOL DISTRICT FIRE DISTRICT TELEPHONE SERVICE POWER SOURCE RESIDENTIAL TABLE WEST HILL PRELIMINARY PLAT SOUNDBUILT HOMES AUBURN, WASHINGTON FOR SITE ADDRESSES SUBDIVISION BREAKDOWN RESTRICTIONS NOTES PLT18-0004 OWNER EXHIBIT 6 97 of 291 S 294TH ST 59TH AVE S57TH AVE S58TH AVE S± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± 58TH AVE SDESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10PRELIMINARY PLATP2 VERTICAL DATUM BENCHMARK NOTESRESTRICTIONS HORIZONTAL DATUM / BASIS OF BEARINGS REFERENCES LEGAL DESCRIPTION EXHIBIT 6 98 of 291 COMBINED PROPERTY AREA S 294TH ST 59TH AVE S57TH AVE S58TH AVE SDESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10EXISTING FEATURES PLAN / FIELD TOPOGRAPHYP3 VERTICAL DATUM BENCHMARK RESTRICTIONS HORIZONTAL DATUM / BASIS OF BEARINGS REFERENCES LEGAL DESCRIPTION NOTES EXHIBIT 6 99 of 291 S 294TH ST 59TH AVE S57TH AVE S58TH AVE S± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± C C A A D D B B 59TH AVE SDESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10CONCEPTUAL ROAD AND GRADING PLANP4 VERTICAL DATUM BENCHMARK SECTION A-A: 58TH AVE S (LOCAL RESIDENTIAL) SECTION B-B: TRACT A (PRIVATE STREET) SECTION C-C: 59TH AVE S (LOCAL RESIDENTIAL) SECTION D-D: S 294TH ST (LOCAL RESIDENTIAL) EXHIBIT 6 100 of 291 59TH AVE S± ± ± 59TH AVE S 59TH AVE S 300 310 320 330 340 350 4+004+505+005+506+006+507+007+508+008+509+009+5010+0010+5011+0011+5012+00 VERTICAL SIGHT DISTANCE (DESIGN SPEED 30 MPH)DESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10CONCEPTUAL SIGHT DISTANCE PLANP5 VERTICAL DATUM BENCHMARK EXHIBIT 6 S 294TH ST 59TH AVE S57TH AVE S58TH AVE STRACT E 13 16 17 TRACT C 5 TRACT D ROW TRACT A 19 18 4 123 8 109 7 6 B B 13 1112 TRACT B A A DESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10CONCEPTUAL UTILITY PLANP6 VERTICAL DATUM BENCHMARK EXHIBIT 6 58TH AVE S 330 340 350 360 330 340 350 360 0+00 0+50 1+00 1+50 2+00 2+50 TRACT A 310 320 330 340 350 310 320 330 340 350 5+00 5+50 6+00 6+50 7+00 7+50 8+00 8+50 59TH AVE S 6+006+507+007+508+008+509+009+5010+0010+5011+0011+50 TRACT D 330 340 350 330 340 350 10+00 10+50 11+00 11+50 12+00 12+50 S 294TH ST 330 340 350 330 340 350 0+00 0+50 1+00 1+50 2+00 2+50 3+00 3+50 4+00 300 310 320 300 310 320 DESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10CONCEPTUAL UTILITY PROFILESP7 EXHIBIT 6 VAULT SECTION A-A 300 310 320 330 300 310 320 330 0+00 0+50 1+00 1+30 VAULT SECTION B-B 300 310 320 330 300 310 320 330 0+50 1+00 1+20 TRACT B B B A A 59TH AVE STRACT A TRACT B 59TH AVE STRACT B 59TH AVE SDESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10DETENTION VAULT DETAILSP8 CONTROL STRUCTUREDETENTION VAULT INTERIOR PLAN VIEW VACTOR TRUCK TURN AROUND ANALYSIS DETENTION VAULT EXTERIOR EXHIBIT 6 ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± X S 294TH ST 59TH AVE S57TH AVE S58TH AVE SDESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10 SCALE: 1" = 30' PRELIMINARY TREE RETENTION PLAN TREE RETENTION CALCULATIONS EXISTING ONSITE TREES: TREES PROPOSED FOR RETENTION: TREES PROPOSED FOR REMOVAL: 109 5 104 PRELIM. TREE RETENTION PLANP9 TREE TO BE RETAINED (TYP.) TREE TO BE REMOVED (TYP.)WETLAND BUFFER (TYP.) WETLAND (TYP.) EXHIBIT 6 ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± ± S 294TH ST 59TH AVE S57TH AVE S58TH AVE SRESTORATION TREES QTY BOTANICAL NAME COMMON NAME SIZE SPACING COMMENTS 10 ACER CIRCINATUM VINE MAPLE 6` HT. MIN.AS SHOWN MULTI-STEMMED STREET TREES QTY BOTANICAL NAME COMMON NAME SIZE SPACING COMMENTS 16 CARPINUS BETULUS `FASTIGIATA`PYRAMIDAL EUROPEAN HORNBEAN 2" CAL. MIN.AS SHOWN STREET TREE QUALITY SHRUBS QTY BOTANICAL NAME COMMON NAME SIZE SPACING COMMENTS 20 THUJA OCCIDENTALIS `SMARAGD`EMERALD GREEN ARBORVITAE 3 GAL./24" HT. MIN.4` O.C. RESTORATION PLANTING QTY BOTANICAL NAME COMMON NAME SIZE SPACING COMMENTS 45 NATIVE SHRUB AND GROUNDCOVER MIX 2 GAL. MIN.4` O.C.FULL & BUSHY PLANT SET CROWN OF PLANT AT FINISHED GRADE 2" LAYER MULCH; TAPER TO CROWN SAUCER 2" HIGH FINISHED GRADE ROOTBALL TOPSOIL BACKFILL & FERTILIZER ROUGHEN ALL SURFACES OF PIT CUT NEW ROOT MASS TO STIMULATE NEW ROOT GROWTH UNDISTURBED NATIVE SOIL 2 X ROOTBALL DIA. 1 1 2 X ROOTBALL DIA. DETAIL: PLANTING SHRUB NOT TO SCALE DETAIL: STREET TREE PLANTING SOURCE: CITY OF AUBURN NOT TO SCALE 3' 1 1 2 X ROOTBALL DIMENSION 1' DETAIL: PLANTING DECIDUOUS TREE STAKES SHALL EXTEND A MIN. OF 12" INTO UNDISTURBED SOIL 2 x ROOTBALL DIA. RUBBER HOSE AT TREE; HOSE SHALL BE LONG ENOUGH TO ACCOMMODATE 1 YEAR'S GROWTH AND BUFFER ALL BRANCHES FROM THE WIRE 3 HARDWOOD STAKES OR OTHER APPROVED MATERIAL; ALL STAKES TO BE DRIVEN OUTSIDE THE ROOTBALLL, AT 120° SPACING GALVANIZED WIRED OR CABLE; TWIST WIRE TO TIGHTEN ONLY ENOUGH TO KEEP FROM SLIPPING (ALLOW FOR SOME TRUNK MOVEMENT) STAKING NOTES: PLANT TREE SO THAT THE TRUNK CROWN IS VISIBLE AT THE TOP OF THE ROOTBALL; SET TOP OF ROOTBALL FLUSH TO GRADE; DO NOT COVER THE TOP OF THE ROOTBALL WITH SOIL MIN. 2" MULCH; DO NOT PLACE IN CONTACT WITH TRUNK 4" HIGH EARTH SAUCER AROUND EDGE OF PLANTING PIT FINISH GRADE ROUGHEN EDGES OF PIT REMOVE ALL TWINE, WIRE AND BURLAP FROM TOP HALF OF ROOTBALL; NON BIODEGRADABLE MATERIAL SHALL BE REMOVED COMPLETELY TAMP TOPSOIL BACKFILL AROUND ROOTBALL BASE FIRMLY WITH FOOT PRESSURE TO AVOID SHIFT OF ROOTBALL PLACE ROOTBALL ON UNEXCAVATED/UNDISTRUBED NATIVE SOIL PEDESTAL TO PREVENT SETTLING NOT TO SCALE GROUND COVERS QTY BOTANICAL NAME COMMON NAME SIZE SPACING COMMENTS 1,404 SF LAWN SOD9/16/2019 1:28 PMJ:\2018\18069\LANDSCAPE\PRELIMINARY\SHEETS\18069 P10.DWGDESIGN12100 NE 195th St, Suite 300 Bothell, Washington 98011 425.885.7877CIVIL ENGINEERINGLANDSCAPE ARCHITECTUREPLANNINGSURVEYING18069WEST HILLSOUNDBUILT HOMESSE1/4, NW1/4, SEC. 02, TWP. 21 N., RGE. 04 E., W.M. 10 SCALE: 1" = 30' PRELIMINARY LANDSCAPE PLAN PLANT SCHEDULE PRELIMINARY LANDSCAPE PLANP10 TREE TO BE RETAINED (TYP.) STREET TREE (TYP.) LAWN (TYP.) NOTES PROJECT NOTES 1.ALL PLANTING SHALL COMPLY WITH ACC 18.50 REQUIREMENTS. 2.ALL PLANT MATERIAL WITHIN SIGHT DISTANCE TRIANGLES SHALL BE MAINTAINED TO PROVIDE VISUAL CLEARANCE BETWEEN 3' AND 8' SO AS TO NOT OBSTRUCT SIGHT LINES. STREET TREES SHALL BE LIMBED UP TO 8' ABOVE FINISH GRADE. 3.STREET TREE MAINTENANCE IS THE RESPONSIBILITY OF THE ADJACENT LANDOWNER UPON OCCUPANCY. 4.RIGID ROOT BARRIER AT 24" DEPTH SHALL BE USED FOR ALL PLANTER STRIP PLANTING AREAS. SPECIES AND SPACING PER CITY OF AUBURN DESIGN STANDARDS STREET TREE LIST WETLAND BUFFER (TYP.) WETLAND (TYP.) VACCINIUM OVATUM GAULTHERIA SHALLON SYMPHORICAPOS ALBUS EVERGREEN HUCKLEBERRY SALAL SNOWBERRY PROPOSED RESTORATION TREE (TYP.) PROPOSED RESTORATION SHRUB AND GROUNDCOVER MIX (TYP.) SHRUB (TYP.) SITE DISTANCE TRIANGLE (TYP.) EXHIBIT 6 1 Critical Area Study Of the West Hills Plat 29241 & 29255 59th Ave. S. Auburn, Washington Tax Parcel Numbers: 022104-9044 & 9071 Southwest 1/4 of Section 2, Township 21 N, Range 4 E of the Willamette Meridian Prepared for: Sound Built Development P.O. Box 73790 Puyallup, WA 98371 John Harness john@soundbuilthomes.com 253-677-9234 Dated: July 20, 2018 Revised March 3, 2019 Prepared by: Jeffery S. Jones, Professional Wetland Scientist EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. i Table of Contents 1.0 Project Description..........................................................................................................1 2.0 Site Address, Identification and Directions ....................................................................1 3.0 Methodology ...................................................................................................................1 4.0 General Site Description .................................................................................................1 5.0 Vegetation .......................................................................................................................2 5.1 Vegetation Methodology ..............................................................................................2 5.2 Vegetation Results ........................................................................................................2-3 6.0 Hydrology .......................................................................................................................3 6.1 Hydrology Methodology ...............................................................................................3 6.2 Hydrology Results ........................................................................................................3-4 7.0 Soils.................................................................................................................................4 7.1 Soils Methodology ........................................................................................................4 7.2 Soil Series .....................................................................................................................4 7.3 Soils Results ..................................................................................................................4-5 8.0 Stream Determination, Rating, and Buffers ....................................................................5 9.0 Wetland Determination, Rating, and Buffers .................................................................6 10.0 Impacts ..........................................................................................................................6 11.0 Authority .......................................................................................................................6 12.0 Limitations ....................................................................................................................6 13.0 References .....................................................................................................................7 Tables 1.0 Plant Indicator Status ......................................................................................................2 Attachments Vicinity Map King County Assessor’s Property Details Soils Map DNR-FPARS Water Type Map Routine Field Data Forms Wetland Rating Data Forms Photos Wetland Assessment Unit (AU) & Sample Location map SAMP Email Wetland Critical Area Map (provided by land surveyor) EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 1 1.0 Project Description The applicant proposes to plat the subject parcels into single-family lots. This study was conducted to determine the type and extent of wetlands and streams on and near the site. 2.0 Site Address, Identification, and Directions The properties are adjoining tax parcels located at 29241 and 29255 59th Ave. S., Auburn, Washington 98001 (see attached Vicinity Map). The tax parcel numbers are 022104-9044 and 022104-9071. The properties are in the Northwest quarter of Section 2, Township 22 North, Range 4 East, of the Williamette Meridian. Directions to the site from downtown Auburn are as follows: 1. Head east on E. Main St. 2. Turn left onto M St. N.E. 3. Continue onto Harvey Road 4. At Starbucks continue onto 15th St. N.E. 5. Turn right onto W. Valley Hwy. N. 6. Turn left onto S. 292nd St. 7. Continue to 65th Ave. S. 8. 64th Ave. S. turns slight right and becomes S. 292nd St. 9. Turn right onto 64th Ave. S. 10. Continue onto S. 296th 11. Turn right onto 59th Ave. S. 12. Continue to street address 3.0 Methodology The wetland assessment and delineation were performed by Jeffery S. Jones PWS, using the Routine Determination methodology as described in the Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (COE, 2008), and the Washington State Wetlands Identification and Delineation Manual (DOE, 1997). The Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region data forms were used for this wetland determination (COE, 2008). “The regional supplement is designed for use with the current version of the Corps Manual and all subsequent versions.” Where differences in the two documents occur, and there are significant differences, the Regional Supplement takes precedence over the Corps Manual (COE, 2008). Wetland are classified according to the 2004 (2008 update) Washington State Department of Ecology methodology (DOE, 2004, Publication No. 04-06-025). 4.0 General Site Description The properties are adjoining 2.38-acre rectangles. They have existing single-family residences on the east sides, large lawns and undeveloped fields and pasture on the west half, see attached King County Imap 2017 aerial photo. EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 2 5.0 Vegetation 5.1 Vegetation Methodology Hydrophytic vegetation has adaptations that allow these species to survive in saturated or inundated environments. These environments are classified according to the Classification of Wetlands and Deepwater Habitats of the United States (Cowardin, 1979). The probability of plant species being found in wetland environments is been determined in the Western Mountains, Valleys, and Coast, 2016 Regional Wetland Plant List (Lichvar, et. al., 2016). An indicator status was applied to each species according to its probability of occurring in wetlands (see Table 1). Table 1. Plant Indicator Status Indicator Category Symbol Occurrence in Wetlands Obligate Wetland OBL > 99% Facultative Wetland FACW 67-99% Facultative FAC 34-67% Facultative Upland FACU 1-33% Upland UPL < 1% Vegetation data was recorded at six sample locations. At each sample location, the dominant plant species were assessed by indicator status to determine if the plant community was hydrophytic. Rules for determining dominant species are from the Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (COE, 2008). Dominants were determined using the 50/20 rule. Using this rule, percent cover for each stratum was added by order of descending cover until 50% cover was reached, these species were considered dominants. The next most common species was also included as a dominant if it had over 20% cover. 5.2 Vegetation Results At sample location 1 (SL-1), the plant community is dominated by Douglas fir (Pseudotsuga menziesii, FACU), unidentified grass, and common dandelion (Taraxacum officinale, FACU). The indicator status for the grass species was assumed to be FAC. The plant community is non- hydrophytic because not more than 50% of the plant species are FAC or wetter. At sample location 2 (SL-2), the plant community is dominated by unidentified grass, and common dandelion (Taraxacum officinale, FACU), and Himalayan blackberry (Rubus armeniacus, FAC). The indicator status for the grass species was assumed to be FAC. The plant community is hydrophytic because more than 50% of the plant species are FAC or wetter. At sample location 3 (SL-3), the plant community is dominated by red alder (Alnus rubra, FAC), unidentified grass, and common dandelion (Taraxacum officinale, FACU), and Himalayan blackberry (Rubus armeniacus, FAC). The indicator status for the grass species was assumed to be FAC. The plant community is hydrophytic because more than 50% of the plant species are FAC or wetter. At sample location 4 (SL-4), the plant community is dominated by big-leaf maple (Acer macrophyllum, FACU), red alder (Alnus rubra, FAC), creeping buttercup (Rananculus repens, FAC), common dandelion (Taraxacum officinale, FACU), and Himalayan blackberry (Rubus armeniacus, FAC). The plant community is hydrophytic because more than 50% of the dominant EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 3 species are OBL, FACW, or FAC (see attached field data sheet). At sample location 5 (SL-5), the plant community is dominated by Western red cedar (Thuja plicata, FAC), red alder (Alnus rubra, FAC), osoberry (Oemleria cerasiformis, FACU), salmonberry (Rubus spectabilis, FAC), skunk cabbage (Lysichiton americanum, OBL), and lady fern (Athyrium filix-femina, FACW), English ivy (Hederal helix, FACU), and Himalayan blackberry (Rubus armeniacus, FAC). The plant community is hydrophytic because more than 50% of the dominant species are OBL, FACW, or FAC. At sample location 6 (SL-6), the plant community is dominated by red alder (Alnus rubra, FAC), holly (Ilex aquifollum, FACU), salmonberry (Rubus spectabilis, FAC), skunk cabbage (Lysichiton americanum, OBL), and lady fern (Athyrium filix-femina, FACW), and Himalayan blackberry (Rubus armeniacus, FAC). The plant community is hydrophytic because more than 50% of the dominant species are OBL, FACW, or FAC. At sample location 7 (SL-7), the plant community is dominated by salmonberry (Rubus spectabilis, FAC), and Himalayan blackberry (Rubus armeniacus, FAC). The plant community is hydrophytic because more than 50% of the dominant species are OBL, FACW, or FAC. 6.0 Hydrology 6.1 Hydrology Methodology The presence or absence of primary and secondary hydrologic indicators was determined at each sample location by evaluating a variety of direct and indirect indicators. In addition to direct visual observation of inundation or saturation, secondary hydrologic indicators were used to infer wetland hydrology. Secondary indicators include oxidized channels (rhizospheres) associated with living roots and rhizomes, water marks on vegetation or fixed objects, drift lines, water-borne sediment deposits, water stained leaves, surface scoured areas, wetland drainage patterns, morphological plant adaptations, and hydric soil characteristics. The presence of wetland hydrology was determined at each sample location by evaluating a variety of direct and indirect indicators. In addition to direct visual observation of inundation or saturation, secondary hydrologic indicators were used to infer wetland hydrology. Secondary indicators include oxidized channels (rhizospheres) associated with living roots and rhizomes, water marks on vegetation or fixed objects, drift lines, water-borne sediment deposits, water stained leaves, surface scoured areas, wetland drainage patterns, morphological plant adaptations, and hydric soil characteristics. 6.2 Hydrology Results SL-1 does not have wetland hydrology. The soil profile is dry to the surface. A water table is not present within the upper 16 inches of the soil profile. There are no primary or secondary indicators of wetland hydrology. SL-2 does not have wetland hydrology. The soil profile is dry to the surface. A water table is not present within the upper 16 inches of the soil profile. There are no primary or secondary indicators of wetland hydrology. SL-3 does not have wetland hydrology. The soil profile is dry to the surface. A water table is not EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 4 present within the upper 16 inches of the soil profile. There are no primary or secondary indicators of wetland hydrology. SL-4 does not have wetland hydrology. The soil profile is dry to the surface. A water table is not present within the upper 16 inches of the soil profile. There are no primary or secondary indicators of wetland hydrology. SL-5 has wetland hydrology. The water table is present at a depth of 6 inches below the soil surface. Soils are saturated to the soil surface. SL-6 has wetland hydrology. The water table is present at the soil surface. SL-7 has wetland hydrology. The water table is present at the soil surface. 7.0 Soils 7.1 Soils Methodology The procedures for soil sampling are provided in the Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region (COE, 2008). Hydric soils are soils are either organic soils (peats and mucks) or are mineral soils that are saturated long enough to produce soil properties associated with a reducing environment. These soils have hydric characteristics such as a reduced matrix (a matrix that changes color when exposed to air), redox depletions (gleying), or redox concentrations (mottles). 7.2 Soil Series The USDA National Resource Conservation Service (NRCS) mapped the soils on the subject property as Alderwood gravelly sandy loam. Alderwood typically has inclusion of Norma silt or sandy loam in depressions and drainage patterns. 7.3 Soils Results The soil at SL-1 is an Alderwood gravelly sandy loam. Alderwood is a non-hydric soil series. From 0 to 6 inches, the soil is a dark brown (10YR 3/2) gravelly sandy loam (MacBeth, 2000). From 6-16 inches, the soil is brown (10YR 4/4) gravelly sandy loam. The soil is non-hydric because it has a four-chroma matrix immediately below the “A” horizon or at ten inches, whichever is shallower (DOE, 1997). The soil at SL-2 is an Alderwood gravelly sandy loam. Alderwood is a non-hydric soil series. From 0 to 2 inches, the soil is a dark brown (10YR 3/2) gravelly sandy loam. From 2-8 inches, the soil is dark brown (10YR 3/3) gravelly sandy loam. From 8-16+ inches, the soil is brown (10YR 4/4) gravelly sandy loam. The soil is non-hydric because it has a four-chroma matrix immediately below the “A” horizon or at ten inches, whichever is shallower (DOE, 1997). The soil at SL-3 is an Alderwood gravelly sandy loam. Alderwood is a non-hydric soil series. From 0 to 4 inches, the soil is a dark brown (10YR 3/2) gravelly sandy loam. From 4-8 inches, the soil is dark brown (10YR 3/3) gravelly sandy loam. From 8-16+ inches, the soil is brown (10YR 4/4) gravelly sandy loam. The soil is non-hydric because it has a four-chroma matrix immediately below the “A” horizon or at ten inches, whichever is shallower (DOE, 1997). EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 5 The soil at SL-4 is an Alderwood gravelly sandy loam. Alderwood is a non-hydric soil series. From 0 to 2 inches, the soil is a dark brown (10YR 3/2) gravelly sandy loam. From 2-14 inches, the soil is dark brown (10YR 4/2) gravelly sandy loam with 10YR 5/8 mottles. The soil is hydric because it has a two-chroma matrix with mottles, immediately below the “A” horizon or at ten inches, whichever is shallower (DOE, 1997). The soil at SL-5 is a hydric Norma sandy loam. From 0 to 5 inches, the soil is a very dark gray (10YR 3/1) sandy loam. From 5-18+ inches, the soil matrix is a gray (10YR 5/1) sandy loam. The soil is hydric because it has a one-chroma matrix immediately below the “A” horizon or at ten inches, whichever is shallower (DOE, 1997). The soil at SL-6 is a hydric Norma sandy loam. From 0 to 6 inches, the soil is a very dark gray (10YR 3/1) sandy loam. From 6-16+ inches, the soil matrix is a gray (10YR 5/1) sandy loam. The soil is hydric because it has a one-chroma matrix immediately below the “A” horizon or at ten inches, whichever is shallower (DOE, 1997). The soil at SL-7 is a hydric Norma sandy loam. From 0 to 18+ inches, the soil is a black (10YR 2/1) gravelly sandy loam. The soil is hydric because it has a one-chroma matrix immediately below the “A” horizon or at ten inches, whichever is shallower (DOE, 1997). 8.0 Stream Determination, Ratings, and Buffers A stream known as Mullens Creek is located off-site of a portion of the north property line and west of the site. Mullens Creek crosses the northwest corner and north property line, of the northern most parcel. There are several smaller ditch systems connecting to Mullens Creek. A wetland located south of the southern-most parcel outflows in a channel that is also tributary to Mullens Creek. These streams are shown on the attached critical areas map. 9.0 Wetland Determination, Ratings, and Buffers The west end of the property is wetland, identified as Mullens Creek A. The soils are a hydric Norma sandy loam. The plant community is dominated by wetland indicator species including obligate wetland plants species. The water table at or near the soil surface. Seepage springs a nd the wetland to the south are the sources of hydrology. Mullens Creek is located off-site but within the wetland. The wetland is a Palustrine forested wetland (PFO) (Cowardin, 1979). Wetland A rates as a Category III wetland with a total score of 45 and a habitat score 17. The maximum buffer width is 50 feet and the minimum buffer is 25 feet, according to Auburn Municipal Code, 16.10.090.E.1. The wetland minimum buffer of 25 feet is recommended, because the buffer for Wetland A will be restored to a native plant community. minimum wetland buffer provides a larger buffer than required for the stream. Below a steep slope, along the north property line, there is another Wetland identified as Mullens Creek B. Mullens Creek flows off-site through a neighboring properties backyard, where there appears to be no wetland adjacent to it. Therefore, Mullens Creek B is rated independently of wetland Mullens Creek A. The soil is a Norma silt loam soil. The water table is at and near the soil surface. The plant community is dominated by Himalayan blackberry, an invasive plant species which has a FAC indicator status. Mullens Creek B rates as a Category III with a total score of 38 points and a habitat score of 14. The maximum buffer width is 50 feet and the minimum buffer is 25 feet, according to Auburn Municipal Code, 16.10.090.E.1. The wetland EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 6 minimum buffer of 25 feet is recommended, because the buffer for Wetland B will be restored to a native plant community. minimum wetland buffer provides a larger buffer than required for the stream. The remainder of the subject property is upland. The soil is a non-hydric Alderwood gravelly sandy loam with a three to four-chroma matrix. There are no indicators of wetland hydrology. The soils profiles are dry. 10.0 Impacts According to the Suzanne Anderson, USACOE, the Special Area Management Plan, known as SAMP, was never adopted and is not in effect. A copy of a recent email from Suzanne Anderson is attached. There are no endangered or threatened plants or animals on or near the site, according to the DNR National Heritage Program and WDFW Priority Habitats and Species data. Therefore, there are not impacts to endangered or threatened plants or animals. The proposed site plan avoids all direct impacts to wetlands and streams. Limited buffer averaging may be proposed to make the buffer and rear lot lines straighter. The wetland buffer will in no location be less than 25 feet. The civil engineer has prepared pre-construction and post-construction hydrologic calculations and designed a stormwater dispersion system that will ensure the contributing on-site hydrology to the wetlands and stream is maintained. The buffer areas will be cleared, graded, enhanced with native vegetation according to an approved Mitigation Plan. The buffer areas will be placed in a Native Growth Protection Tract, split-rail fenced and signed. 11.0 Authority This wetland determination is in accordance with Section 404 of the Clean Water Act, the objective of which is to “maintain and restore the chemical, physical, and biological integrity of the waters of the United States” (DOE, 1997). Wetlands are “areas that are inundated or saturated by surface or ground water at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions. Wetlands generally include swamps, marshes, bogs, and similar areas (CFR, 2018). 12.0 Limitations Wetland determinations and delineations are not final until approved by regulatory agencies and/or local jurisdictions. J. S. Jones and Associates, Inc. does not guarantee acceptance or approval by regulatory agencies, or that any intended use will be achieved. EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 7 13.0 References CFR, 2018. Title 40, Chapter I, Subchapter H, Part 230, Section 404(b), Subpart A, Definitions. https://www.ecfr.gov/cgi-bin/text- idx?SID=7977290449ab243f2865159951305a77&node=40:25.0.1.3.24&rgn=div5#se40.27.230_1 3. COE. 2008. Interim Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Western Mountains, Valleys, and Coast Region. U.S. Army Engineer Research and Development Center, Environmental Laboratory, ERDC/EL TR-08-13, Vicksberg, MS. Cowardin, Lewis M. 1979. Classification of Wetlands and Deepwater Habitats of the United States. U.S. Fish and Wildlife Service. Jamestown, North Dakota. DOE. 1997. Washington State Wetlands Identification and Delineation Manual. Publication # 96- 94. Lichvar, R.W., D.L. Banks, W.N. Kirchnir, and N.C. Melvin. Western Mountains, Valleys, and Coast, 2016 Regional Wetland Plant List . The National Wetland Plant List: 2016 Wetland Ratings. Phytoneuron 2016-30: 1-17. Published 28 April 2016. ISSN 2153 733X (https://wetland_plants.usace.army.mil).. MacBeth. 2000. Munsell Soil Color Charts-Revised Washable Edition. 617 Little Britain Road, New Windsor, NY 12553. 10p + 9 charts. EXHIBIT 7 July 2018 J. S. Jones and Associates, Inc. 8 Attachments EXHIBIT 7 Vicin ity M ap Date: 3 /16 /20 18 Notes: Th e infor matio n in clu de d on t his map has been comp ile d b y Kin g Count y staf f from a variety of source s an d is su bject to cha ng ewithout n otice. Kin g Co unt y makes no re present ations o r wa rra nties, exp re ss o r im plied , a s to accu ra cy, complet en ess, t ime lin ess,or rig hts to the use of such informa tion . This d ocu me nt is not intended for u se as a survey pr od uct. King Cou nty shall n ot be lia blefor a ny g en er al, sp ecial, indirect, incide ntal, o r conse qu en tial damag es including , but not limited to , lost revenu es or lo st profitsresulting from th e use or m isu se of t he info rmat ion cont aine d on this map . An y sale of this map or in formation o n t his map isprohibited except by written p er mission of King County. EXHIBIT 7 Fair, Equitable, and Understandable Property Valuations You're in: Assessor >> Look up Property Info >> eReal Property Department of Assessments 500 Fourth Avenue, Suite ADM- AS-0708, Seattle, WA 98104 Office Hours: Mon - Fri 8:30 a.m. to 4:30 p.m. TEL: 206- 296-7300 FAX: 206- 296-5107 TTY: 206- 296-7888 Send us mail ADVERTISEMENT New Search Property Tax Bill Map This Property Glossary of Terms Area Report Print Property Detail PARCEL DATA Parcel 022104-9044 Name SLOAN PAUL J Site Address 29255 59TH AVE S 98001 Residential Area 027-011 (SW Appraisal District) Property Name Jurisdiction AUBURN Levy Code 0117 Property Type R Plat Block / Building Number Plat Lot / Unit Number Quarter-Section-Township- Range NW-2 -21-4 Legal Description S 1/2 OF S 1/2 OF NE 1/4 OF SE 1/4 OF NW 1/4 LESS CO RD PLat Block: Plat Lot: LAND DATA Highest & Best Use As If Vacant MULTI-FAMILY DWELLING Highest & Best Use As Improved PRESENT USE Present Use Single Family(Res Use/Zone) Land SqFt 103,672 Acres 2.38 Percentage Unusable Unbuildable NO Restrictive Size Shape NO Zoning R5 Water WATER DISTRICT Sewer/Septic PRIVATE Road Access PUBLIC Parking Street Surface PAVED Views Waterfront Rainier Territorial GOOD Olympics Cascades GOOD Seattle Skyline Puget Sound Lake Washington Lake Sammamish Lake/River/Creek Other View Waterfront Location Waterfront Footage 0 Lot Depth Factor 0 Waterfront Bank Tide/Shore Waterfront Restricted Access Waterfront Access Rights NO Poor Quality NO Proximity Influence NO Designations Nuisances Historic Site Current Use (none) Nbr Bldg Sites Adjacent to Golf Fairway NO Adjacent to Greenbelt NO Other Designation NO Deed Restrictions NO Development Rights Purchased NO Easements NO Native Growth Protection Easement NO DNR Lease NO Topography Traffic Noise Airport Noise Power Lines NO Other Nuisances NO Problems Water Problems NO Transportation Concurrency NO Other Problems NO Environmental Environmental NO BUILDING Building Number 1 Year Built 1961 Year Renovated 0 Stories 1 Living Units 1 Grade 7 Average Grade Variant 0 Condition Average Basement Grade 6 Low Average 1st Floor 1,300 1/2 Floor 0 2nd Floor 0 Upper Floor 0 Click the camera to see more pictures. Picture of Building 1 ADVERTISEMENT Reference Links: King County Tax Links Property Tax Advisor Washington State Department of Revenue (External link) Washington State Board of Tax Appeals (External link) Board of Appeals/Equalization Districts Report iMap Recorder's Office Scanned images of surveys and other map documents Notice mailing date: 05/31/2018 Search Kingcounty.gov Home How do I... Services About King County Departments King County Department of Assessments EXHIBIT 7 Finished Basement 800 Total Finished Area 2,100 Total Basement 1,300 Basement Garage 0 Unfinished 1/2 0 Unfinished Full 0 AGLA 1,300 Attached Garage 0 Bedrooms 4 Full Baths 1 3/4 Baths 1 1/2 Baths 0 Heat Source Oil Heat System Forced Air Deck Area SqFt 400 Open Porch SqFt 0 Enclosed Porch SqFt 60 Brick/Stone 0 Fireplace Single Story 0 Fireplace Muilti Story 1 Fireplace Free Standing 0 Fireplace Additional 0 AddnlCost 0 Obsolescence 0 Net Condition 0 Percentage Complete 0 Daylight Basement YES View Utilization Floor plan of Building 1 TAX ROLL HISTORY Account Valued Year Tax Year Omit Year Levy Code Appraised Land Value ($) Appraised Imps Value ($) Appraised Total Value ($) New Dollars ($) Taxable Land Value ($) Taxable Imps Value ($) Taxable Total Value ($) Tax Value Reason 022104904408 2018 2019 0117 186,000 193,000 379,000 0 186,000 193,000 379,000 022104904408 2017 2018 0117 178,000 163,000 341,000 0 178,000 163,000 341,000 022104904408 2016 2017 0117 185,000 183,000 368,000 0 185,000 183,000 368,000 022104904408 2015 2016 0117 176,000 165,000 341,000 0 176,000 165,000 341,000 022104904408 2014 2015 0117 169,000 156,000 325,000 0 169,000 156,000 325,000 022104904408 2013 2014 0117 169,000 102,000 271,000 0 169,000 102,000 271,000 022104904408 2012 2013 0117 169,000 98,000 267,000 0 169,000 98,000 267,000 022104904408 2011 2012 0117 131,000 105,000 236,000 0 131,000 105,000 236,000 022104904408 2010 2011 0117 144,000 115,000 259,000 0 144,000 115,000 259,000 022104904408 2009 2010 0117 144,000 125,000 269,000 0 144,000 125,000 269,000 022104904408 2008 2009 0117 144,000 189,000 333,000 0 144,000 189,000 333,000 022104904408 2007 2008 3494 138,000 168,000 306,000 0 138,000 168,000 306,000 022104904408 2006 2007 3494 123,000 136,000 259,000 0 123,000 136,000 259,000 022104904408 2005 2006 3494 121,000 144,000 265,000 0 121,000 144,000 265,000 022104904408 2004 2005 3494 112,000 133,000 245,000 0 112,000 133,000 245,000 022104904408 2003 2004 3494 108,000 126,000 234,000 0 108,000 126,000 234,000 022104904408 2002 2003 3494 103,000 118,000 221,000 0 103,000 118,000 221,000 022104904408 2001 2002 3494 99,000 103,000 202,000 0 99,000 103,000 202,000 022104904408 2000 2001 3494 95,000 92,000 187,000 0 95,000 92,000 187,000 022104904408 1999 2000 3494 86,000 113,000 199,000 0 86,000 113,000 199,000 022104904408 1998 1999 3494 81,000 79,000 160,000 0 81,000 79,000 160,000 022104904408 1997 1998 3494 0 0 0 0 75,000 72,000 147,000 022104904408 1996 1997 3494 0 0 0 0 72,000 68,600 140,600 022104904408 1994 1995 3494 0 0 0 0 72,000 68,600 140,600 022104904408 1992 1993 3494 0 0 0 0 70,800 71,100 141,900 022104904408 1990 1991 3494 0 0 0 0 64,400 64,600 129,000 022104904408 1988 1989 3494 0 0 0 0 37,400 59,900 97,300 022104904408 1986 1987 3494 0 0 0 0 37,400 55,700 93,100 022104904408 1984 1985 3493 0 0 0 0 28,500 62,800 91,300 022104904408 1982 1983 3493 0 0 0 0 28,500 62,800 91,300 SALES HISTORY Excise Number Recording Number Document Date Sale Price Seller Name Buyer Name Instrument Sale Reason 2512371 20110930002294 9/29/2011 $277,950.00 MCNEILL PATRICIA A SLOAN PAUL J Statutory Warranty Deed None 2486372 20110412000026 4/6/2011 $0.00 MCNEILL MALCOMB B+MCNEILL PATRICIA A MCNEILL PATRICIA A Deed of Personal Representative Other REVIEW HISTORY PERMIT HISTORY EXHIBIT 7 Information for... 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View King County social media © King County, WA 2018 Privacy Accessibility Terms of use HOME IMPROVEMENT EXEMPTION New Search Property Tax Bill Map This Property Glossary of Terms Area Report Print Property Detail ADVERTISEMENT Updated: March 17, 2016  Share  Tweet  Email  Print Information for...Do more online Get help EXHIBIT 7 Fair, Equitable, and Understandable Property Valuations You're in: Assessor >> Look up Property Info >> eReal Property Department of Assessments 500 Fourth Avenue, Suite ADM- AS-0708, Seattle, WA 98104 Office Hours: Mon - Fri 8:30 a.m. to 4:30 p.m. TEL: 206- 296-7300 FAX: 206- 296-5107 TTY: 206- 296-7888 Send us mail ADVERTISEMENT New Search Property Tax Bill Map This Property Glossary of Terms Area Report Print Property Detail PARCEL DATA Parcel 022104-9071 Name WILKES SUSAN MARIA Site Address 29241 59TH AVE S 98001 Residential Area 027-011 (SW Appraisal District) Property Name Jurisdiction AUBURN Levy Code 0117 Property Type R Plat Block / Building Number Plat Lot / Unit Number Quarter-Section-Township- Range NW-2 -21-4 Legal Description N 1/2 OF S 1/2 OF N 1/2 OF E 1/2 OF SE 1/4 OF NW 1/4 LESS CO RD PLat Block: Plat Lot: LAND DATA Highest & Best Use As If Vacant MULTI-FAMILY DWELLING Highest & Best Use As Improved PRESENT USE Present Use Single Family(Res Use/Zone) Land SqFt 103,672 Acres 2.38 Percentage Unusable Unbuildable NO Restrictive Size Shape NO Zoning R5 Water WATER DISTRICT Sewer/Septic PRIVATE Road Access PUBLIC Parking Street Surface PAVED Views Waterfront Rainier Territorial AVERAGE Olympics Cascades AVERAGE Seattle Skyline Puget Sound Lake Washington Lake Sammamish Lake/River/Creek Other View Waterfront Location Waterfront Footage 0 Lot Depth Factor 0 Waterfront Bank Tide/Shore Waterfront Restricted Access Waterfront Access Rights NO Poor Quality NO Proximity Influence NO Designations Nuisances Historic Site Current Use (none) Nbr Bldg Sites Adjacent to Golf Fairway NO Adjacent to Greenbelt NO Other Designation NO Deed Restrictions NO Development Rights Purchased NO Easements NO Native Growth Protection Easement NO DNR Lease NO Topography Traffic Noise Airport Noise Power Lines NO Other Nuisances NO Problems Water Problems NO Transportation Concurrency NO Other Problems NO Environmental Environmental NO BUILDING Building Number 1 Year Built 1920 Year Renovated 1963 Stories 1.5 Living Units 1 Grade 7 Average Grade Variant 0 Condition Average Basement Grade 1st Floor 1,220 1/2 Floor 890 2nd Floor 0 Upper Floor 0 Picture of Building 1 ADVERTISEMENT Reference Links: King County Tax Links Property Tax Advisor Washington State Department of Revenue (External link) Washington State Board of Tax Appeals (External link) Board of Appeals/Equalization Districts Report iMap Recorder's Office Scanned images of surveys and other map documents Notice mailing date: 05/31/2018 Search Kingcounty.gov Home How do I... Services About King County Departments King County Department of Assessments EXHIBIT 7 Finished Basement 0 Total Finished Area 2,110 Total Basement 0 Basement Garage 0 Unfinished 1/2 0 Unfinished Full 0 AGLA 2,110 Attached Garage 240 Bedrooms 5 Full Baths 1 3/4 Baths 0 1/2 Baths 1 Heat Source Oil Heat System Forced Air Deck Area SqFt 220 Open Porch SqFt 0 Enclosed Porch SqFt 0 Brick/Stone 0 Fireplace Single Story 0 Fireplace Muilti Story 0 Fireplace Free Standing 0 Fireplace Additional 0 AddnlCost 0 Obsolescence 0 Net Condition 0 Percentage Complete 0 Daylight Basement View Utilization Floor plan of Building 1 Accessory Of Building Number: 1 Accessory Type Picture Description SqFt Grade Eff Year %Value Date Valued PRK:CARPORT Shop/CP 22x32 704 1920 TAX ROLL HISTORY Account Valued Year Tax Year Omit Year Levy Code Appraised Land Value ($) Appraised Imps Value ($) Appraised Total Value ($) New Dollars ($) Taxable Land Value ($) Taxable Imps Value ($) Taxable Total Value ($) Tax Value Reason 022104907104 2018 2019 0117 181,000 208,000 389,000 0 181,000 208,000 389,000 022104907104 2017 2018 0117 173,000 177,000 350,000 0 173,000 177,000 350,000 022104907104 2016 2017 0117 180,000 159,000 339,000 0 180,000 159,000 339,000 022104907104 2015 2016 0117 171,000 143,000 314,000 0 171,000 143,000 314,000 022104907104 2014 2015 0117 165,000 135,000 300,000 0 165,000 135,000 300,000 022104907104 2013 2014 0117 165,000 85,000 250,000 0 165,000 85,000 250,000 022104907104 2012 2013 0117 165,000 81,000 246,000 0 165,000 81,000 246,000 022104907104 2011 2012 0117 125,000 126,000 251,000 0 125,000 126,000 251,000 022104907104 2010 2011 0117 138,000 137,000 275,000 0 138,000 137,000 275,000 022104907104 2009 2010 0117 138,000 147,000 285,000 0 138,000 147,000 285,000 022104907104 2008 2009 0117 138,000 214,000 352,000 0 138,000 214,000 352,000 022104907104 2007 2008 3494 132,000 191,000 323,000 0 132,000 191,000 323,000 022104907104 2006 2007 3494 118,000 155,000 273,000 0 118,000 155,000 273,000 022104907104 2005 2006 3494 121,000 129,000 250,000 0 121,000 129,000 250,000 022104907104 2004 2005 3494 112,000 119,000 231,000 0 112,000 119,000 231,000 022104907104 2003 2004 3494 108,000 113,000 221,000 0 108,000 113,000 221,000 022104907104 2002 2003 3494 103,000 110,000 213,000 0 103,000 110,000 213,000 022104907104 2001 2002 3494 99,000 105,000 204,000 0 99,000 105,000 204,000 022104907104 2000 2001 3494 95,000 100,000 195,000 0 95,000 100,000 195,000 022104907104 1999 2000 3494 86,000 136,000 222,000 0 86,000 136,000 222,000 022104907104 1998 1999 3494 81,000 97,000 178,000 0 81,000 97,000 178,000 022104907104 1997 1998 3494 0 0 0 0 75,000 88,000 163,000 022104907104 1996 1997 3494 0 0 0 0 72,000 83,600 155,600 022104907104 1994 1995 3494 0 0 0 0 72,000 83,600 155,600 022104907104 1992 1993 3494 0 0 0 0 70,800 72,800 143,600 022104907104 1990 1991 3494 0 0 0 0 64,400 66,200 130,600 022104907104 1988 1989 3494 0 0 0 0 37,400 51,800 89,200 022104907104 1986 1987 3494 0 0 0 0 37,400 43,900 81,300 022104907104 1984 1985 3493 0 0 0 0 28,500 49,600 78,100 022104907104 1982 1983 3493 0 0 0 0 28,500 49,600 78,100 SALES HISTORY Excise Number Recording Number Document Date Sale Price Seller Name Buyer Name Instrument Sale Reason 1531819 199703100964 3/4/1997 $0.00 SUNSERI MICHAEL C WILKES SUSAN MARIA Quit Claim Deed Divorce Settlement REVIEW HISTORY PERMIT HISTORY EXHIBIT 7 Information for... 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View King County social media © King County, WA 2018 Privacy Accessibility Terms of use HOME IMPROVEMENT EXEMPTION New Search Property Tax Bill Map This Property Glossary of Terms Area Report Print Property Detail ADVERTISEMENT Updated: March 17, 2016  Share  Tweet  Email  Print Information for...Do more online Get help EXHIBIT 7 Soil Map—King County Area, Washington (NRCS Soils Map) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 3/16/2018 Page 1 of 35243020524305052430805243110524314052431705243200524323052430205243050524308052431105243140524317052432005243230555550555580555610555640555670555700555730555760555790555820555850555880 555550 555580 555610 555640 555670 555700 555730 555760 555790 555820 555850 555880 555910 47° 20' 25'' N 122° 15' 53'' W47° 20' 25'' N122° 15' 35'' W47° 20' 17'' N 122° 15' 53'' W47° 20' 17'' N 122° 15' 35'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 50 100 200 300 Feet 0 20 40 80 120 Meters Map Scale: 1:1,670 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. EXHIBIT 7 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 13, Sep 7, 2017 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Jul 8, 2014—Jul 15, 2014 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 (NRCS Soils Map) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 3/16/2018 Page 2 of 3 EXHIBIT 7 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 8.4 79.2% AmC Arents, Alderwood material, 6 to 15 percent slopes 2.2 20.8% Totals for Area of Interest 10.6 100.0% Soil Map—King County Area, Washington NRCS Soils Map Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 3/16/2018 Page 3 of 3 EXHIBIT 7 «k «k «k E EE E E E E E EE E E400 200200400200X F NFNF NNF NF NNFNFN1723044 1723024 1723082 1723084 1723062 1723086 1723064 1723026 1723066 1723042 1723046 1723022 2 35 11 3 1 34 1210 36 FN Date: 3/16/2018 Time: 2:17:32 PM NAD 83 Contour Interval: 40 Feet Application #: ________________________ FOREST PRACTICE ACTIVITY MAP TOWNSHIP 21 NORTH HALF 0, RANGE 04 EAST (W .M.) HALF 0, SECTION 2 1,000 Feet Please use the legend from the FPA Instruction or provide a list of symbols used. ® EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 EXHIBIT 7 SL-1 SL-1 EXHIBIT 7 SL-2 SL-2 EXHIBIT 7 SL-3 SL-3 EXHIBIT 7 SL-4 SL-4 EXHIBIT 7 SL-5 SL-5 EXHIBIT 7 SL-5 soil from restrictive layer SL-6 EXHIBIT 7 SL-7 EXHIBIT 7 SL-7 EXHIBIT 7 Mullens Creek A Mullen s Cree k BSL-7SL-5 SL-6 SL-4 SL-3 SL-2 SL-1 Pictom etr y, Ki ng C ou n ty, K ing C ou nty Date : 7/22/20 18 Notes: ±The informati on included on this map has been compi led by King County staff from a variety of sour ces and issubject to change wi thout notice. King County makes no r epresentati ons or w ar ranties, expr ess or impl ied,as to accurac y, completenes s, timeli ness , or ri ghts to the use of such infor mation. This document is not intendedfor use as a s urvey pr oduct. King County shall not be liable for any gener al, s pecial, i ndir ect, incidental , orconsequential damages incl uding, but not li mited to, lost revenues or lost pr ofits resulting fr om the use or misuseof the information contained on this map. Any sale of this map or infor mati on on this map is pr ohibited except bywritten per mi ssi on of Ki ng County. Wetland Asses sment Unit (AU ) & Samp le Locatio n SketchEXHIBIT 7 EXHIBIT 7 COMBINED PROPERTY AREA S 294TH ST 59TH AVE S57TH AVE S58TH AVE SCRITICAL AREAS EXHIBITWEST HILLSOUND BUILT HOMESEXHIBIT 7 EXHIBIT 7 ////////////////////////58TH AVE S GGGGGGGGGGGG25' Buffer25' BufferWWWWWWWWWWW////// / / ///////////////////////////////////////////////// /////////////////////////////////////////////////////////////////////XXXXXXXXXXXXXSDSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSSS OHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPSSSSSSSSOHPOHP OHPSDSDSDOHPOHPOHPWWWWWWWWWWWWWWS 294TH STSD SD SS SS SS SS SS SSSSSSSDSD SDSD SD SD SD SD SD SD SD SD SDSDSD59TH AVE S 57TH AVE S GCOMBINED PROPERTY AREAXXXXXXXXXXXXXX X XEnhancement Area #28,271 SFEnhancement Area #111,472 SFXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXEnvironmental ConsultantsPROJECT: CLIENT: 1"=30' SCALE DRAWN BY: CHECKED BY: DESIGNED BY: 1 of 3 SHEET APPROVED BY: DATE: CONSULTANT: Wetlands, Streams, and Wildlife J. S. Jones and Associates, Inc. NO. DATE BY REVISION P.O. BOX 1908 ISSAQUAH, WASHINGTON 98027 Jeff Jones Jeff Jones 9/17/2018 Conceptual Buffer Enhancement Plan West Hills Plat Conceptual Buffer Enhancement Plan29241 & 29255 59th Ave. S., Auburn, Washington 98001Parcel No.'s 022104-9044 & 22104-9071NORTHSCALE: 1" = 30'KEYExisting WetlandCONTACT INFORMATIONApplicant:Sound Built DevelopmentBox 73790, Puyallup, WA 98371John Harknessjohn@soundbuilthomes.com253-677-9234Environmental Consultant:J. S. Jones and Associates, Inc.PO Box 1908Issaquah, Washington 98027253-905-5736jeff.jsjones@comcast.netSound Built Development P.O. Box 73790, Puyallup, WA 98371 West Hills Plat 29241 & 29255 59th Ave. S., Auburn, Washington 98001 CONTACT:Wetland BufferEnhancement AreaXXSilt FenceSplit-rail FenceWETLAND BUFFER ENHANCEMENTEnhancement Area #111,472 sfEnhancement Area #28,271 sfTotal Enhancement Area19,743 sfPROJECT REF: _________________________THESE PLANS ARE APPROVED FORCONFORMANCE WITH THE CITY OF AUBURN’SPLANNING DEPARTMENT REQUIREMENTS.APPROVED BY: _________________________DATE APPROVED: ______________________NORTHVicinity Map Not to Scale1 2/22/19 CJ City of Auburn Comments 10/19/18NOTE: A PIPE IN THE WETLAND WILL BE REMOVED. ALL GARBAGE AND DEBRIS WILL BEREMOVED FROM THE WETLAND AND WETLAND BUFFER. ALL STATE AND FEDERAL PERMITSWILL BE OBTAINED FOR THE PIPE REMOVAL WILL BE OBTAINED.2 4/5/19 CJ City of Auburn Comments 3/28/18 EXHIBIT 7EXHIBIT 7 Environmental ConsultantsPROJECT: CLIENT: NONE SCALE DRAWN BY: CHECKED BY: DESIGNED BY: 2 of 3 SHEET APPROVED BY: DATE: CONSULTANT: Wetlands, Streams, and Wildlife J. S. Jones and Associates, Inc. P.O. BOX 1908 ISSAQUAH, WASHINGTON 98027 Jeff Jones Jeff Jones NO. DATE BY REVISIONGENERAL NOTES1. THIS DEVELOPMENT PROJECT SHALL CONFORM TO THE CITY OF AUBURN'SREQUIREMENTS AND BE IN ACCORDANCE WITH THE APPROVED PLANS. ANY CHANGESFROM THE APPROVED PLAN WILL REQUIRE APPROVAL FROM THE OWNER, ENGINEER,AND THE CITY.2.ALL WORKMANSHIP AND MATERIALS SHALL CONFORM TO THE “WASHINGTONSTATE DEPARTMENT OF TRANSPORTATION (WSDOT) STANDARD SPECIFICATIONS FORROAD, BRIDGE, AND MUNICIPAL CONSTRUCTION (CURRENT EDITION),” EXCEPT WHERESUPPLEMENTED OR MODIFIED BY THE CITY'S CONSTRUCTION STANDARDS MANUAL.COPIES OF THE ABOVE DOCUMENTS SHALL BE AVAILABLE AT THE JOB SITE DURINGCONSTRUCTION.3. A PRE-CONSTRUCTION MEETING SHALL BE REQUIRED PRIOR TO THE START OFALL CONSTRUCTION. CONTACT THE COMMUNITY DEVELOPMENT & PUBLIC WORKSDEPARTMENT AT 253-931-3010, TO SCHEDULE A MEETING.4. LOCATIONS SHOWN FOR EXISTING UTILITIES ARE APPROXIMATE. THECONTRACTOR IS CAUTIONED THAT OVERHEAD UTILITY LINES MAY NOT BE SHOWN ONTHE DRAWINGS. IT SHALL BE THE CONTRACTOR'S RESPONSIBILITY TO DETERMINE THETRUE ELEVATIONS AND LOCATIONS OF ALL UNDERGROUND UTILITIES AND THE EXTENTOF ANY HAZARD CREATED BY OVERHEAD UTILITY LINES. IDENTIFICATION, LOCATION,MARKING, AND RESPONSIBILITY FOR UNDERGROUND FACILITIES OR UTILITIES, ISGOVERNED BY THE PROVISIONS OF CHAPTER 19.122 REVISED CODE OF WASHINGTON(RCW). PRIOR TO STARTING CONSTRUCTION, THE CONTRACTOR SHALL CALL ONE-CALL(811) FOR UTILITY LOCATIONS (WATER, SANITARY SEWER, STORM SEWER, GAS, POWER,TELEPHONE, AND CABLE).5. IF A PROPOSED ROUTE IS NOT INCLUDED ON THESE PLANS, A PROPOSED ROUTEAND SCHEDULE FOR HAULING MATERIAL TO THE SITE SHALL BE SUBMITTED TO THE CITYFOR APPROVAL PRIOR TO THE START OF CONSTRUCTION. IF THE CITY BELIEVES THATTHE PROPOSED HAUL ROUTE WILL ADVERSELY IMPACT THE STREET NETWORK, A SEPAAMENDMENT MAY BE REQUIRED TO EVALUATE THE IMPACTS AND DETERMINEMITIGATION REQUIREMENTS BEFORE BEGINNING WORK. HAULING MAY BE LIMITED TOAPPROPRIATE OFF-PEAK HOURS OR ALTERNATIVE ROUTES, AS DETERMINED BY THECITY.6. THE CONTRACTOR SHALL BE RESPONSIBLE FOR PUBLIC SAFETY ON AND AROUNDTHE PROJECT. PRIOR TO THE START OF WORK, ALL METHODS AND EQUIPMENT USEDFOR TRAFFIC CONTROL AND STREET MAINTENANCE SHALL BE SUBMITTED TO THE CITYFOR APPROVAL. CONTRACTORS AND THEIR SURETY SHALL BE LIABLE FOR INJURIESAND DAMAGES TO PERSONS AND PROPERTY SUFFERED BECAUSE OF CONTRACTORSOPERATIONS OR NEGLIGENCE CONNECTED WITH THEM.7. ALL CONSTRUCTION SURVEYING FOR EXTENSIONS OF PUBLIC FACILITIES SHALLBE DONE UNDER THE DIRECTION OF A WASHINGTON LICENSED LAND SURVEYOR OR AWASHINGTON LICENSED PROFESSIONAL CIVIL ENGINEER.8. CERTIFIED DRAWINGS ARE REQUIRED PRIOR TO PROJECT ACCEPTANCE. REFERTO THE CITY'S “RECORD CONSTRUCTION DOCUMENT” HANDOUT. IssuedFebruary 26, 2018 City of Auburn Engineering Design Standards Page 55 Appendix B (continued)GRADING AND EROSION CONTROLNOTES1. WITHIN THE CITY OF AUBURN, ALL REQUIRED SEDIMENTATION AND EROSIONCONTROL FACILITIES INDICATED ON THE PLANS MUST BE CONSTRUCTED AND INOPERATION PRIOR TO LAND CLEARING AND/OR OTHER CONSTRUCTION ACTIVITIES.THESE FACILITIES SHALL BE MAINTAINED AND UPGRADED, IF NECESSARY, TO INSURETHAT SEDIMENT-LADEN WATER AND STORM DRAINAGE RUNOFF DOES NOT IMPACT THEADJACENT PROPERTIES, NATURAL DRAINAGE WAYS, OR THE EXISTING CITY STORMDRAINAGE SYSTEM.2. THE SOURCES FOR ALL MATERIAL IMPORTED TO THE SITE SHALL BE APPROVED BYTHE CITY.3. THE STORM DRAINAGE DETENTION (RETENTION IF INFILTRATION SYSTEM IS USED),SEDIMENTATION AND EROSION CONTROL FACILITIES DEPICTED ON THE APPROVEDDRAWINGS ARE INTENDED TO BE MINIMUM REQUIREMENTS TO MEET ANTICIPATED SITECONDITIONS. ADDITIONAL DRAINAGE AND EROSION CONTROL FACILITIES MAY BEREQUIRED AS SITUATIONS WARRANT DURING CONSTRUCTION. THE IMPLEMENTATION,MAINTENANCE, REPLACEMENT AND ADDITIONS TO THESE CONTROL SYSTEMS SHALL BETHE RESPONSIBILITY OF THE PERMITEE.4. THE TEMPORARY EROSION CONTROL FACILITIES, INCLUDING ALL PERIMETERCONTROLS AND THE DETENTION (RETENTION IF INFILTRATION SYSTEM IS USED),CONTROL PONDS, SHALL REMAIN IN PLACE UNTIL FINAL SITE CONSTRUCTION ISCOMPLETED. AFTER CITY APPROVAL, THE CONTRACTOR WILL BE RESPONSIBLE FORREMOVING ALL TEMPORARY FACILITIES.5. THE CONTRACTOR WILL BE REQUIRED TO WATER THE SITE, AS NECESSARY, TOREDUCE DUST EMISSIONS AS A RESULT OF CONSTRUCTION ACTIVITY.6. NO TRACKING IN THE ROADWAY IS ALLOWED. IF SEDIMENT IS TRACKED ONTO THEROAD, THE ROAD SHALL BE THOROUGHLY AND IMMEDIATELY CLEANED BY SHOVELINGOR PICKUP SWEEPING. TRANSPORT SEDIMENT TO A CONTROLLED SEDIMENT DISPOSALAREA. KEEP STREETS CLEAN AT ALL TIMES.7. ALL AREAS OF ACTIVE EARTHWORK WHICH HAVE THE POTENTIAL FOR EROSIONAND SEDIMENTATION IMPACTS ON ADJACENT PROPERTIES, NATURAL DRAINAGE WAYS,OR THE EXISTING CITY STORM DRAINAGE SYSTEM MUST BE STABILIZED ACCORDING TOTHE FOLLOWING SCHEDULE: FROM MAY 1 TO SEPTEMBER 30, AREAS AT FINAL GRADEAND THOSE THAT ARE SCHEDULE TO REMAIN UN-WORKED FOR MORE THAN SEVEN (7)DAYS SHALL BE STABILIZED. FROM OCTOBER 1 TO APRIL 30 EARTHWORK ACTIVITIESSHALL BE CONDUCTED IN STAGES IN ORDER TO MINIMIZE SOIL EXPOSURE. EXPOSEDSOILS THAT WILL REMAIN UN-WORKED FOR MORE THAN TWO (2) DAYS SHALL BESTABILIZED IMMEDIATELY.Conceptual Buffer Enhancement Plan West Hills Plat Conceptual Buffer Enhancement Plan29241 & 29255 59th Ave. S., Auburn, Washington 98001Parcel No.'s 022104-9044 & 22104-9071Sound Built Development P.O. Box 73790, Puyallup, WA 98371 West Hills Plat 29241 & 29255 59th Ave. S., Auburn, Washington 98001 9/17/2018PROJECT REF: _________________________THESE PLANS ARE APPROVED FORCONFORMANCE WITH THE CITY OF AUBURN’SPLANNING DEPARTMENT REQUIREMENTS.APPROVED BY: _________________________DATE APPROVED: ______________________8' ON CENTER12" TO 16"8"30" TO 42"CONCRETE18" TO 24"4"x4"" SPLIT RAIL POST SPLIT RAIL FENCEFENCE NOTES:INSTALL SPLIT RAIL FENCE ALONG WETLAND BUFFER BOUNDARY AND CLEARINGLIMIT. FENCE MAYBE CONSTRUCTED OF SPLIT RAIL, PRESSURE TREATED RAIL,OF VINYL COATED PLASTIC. THE FENCE MUST ALLOW WILDLIFE TO PASSTHROUGH.SPLIT RAIL FENCE DETAILWETLAND SIGN DETAILNATIVE SOILBACKFILL WITH NATIVE SOILONLY, COMPACT MODERATELYBY HANDPLACE TOP OF ROOTBALL 1INCH ABOVE THE LEVEL OFNATIVE SOIL. BEFORE MULCH,POTTING SOIL SHOULD BEVISIBLE2 INCH DEPTH MEDIUM BARKMULCH NOT TOUCHING STEMREST BOTTOM OF ROOTBALL ONUNDISTURBED NATIVE SOILCUT CIRCLING ROOTS ANDSPREAD OR "BUTTERFLY"ROOTBALLSPREAD A 3 FOOT MINIMUMDIAMETER MULCH RING(DONUT) AROUND THEPLANTING HOLEWIDTH OF PLANTINGHOLE SHALL 3'' WIDER AND 2"DEEPER THAN ROOTBALLSTAKE TREE AT 1/3 HEIGHT OFTREE, USE "TREE TIES" ORENGINEER APPROVEDEQUIVALENT, REMOVE STAKEAND TIE AFTER 1 YEARSTAKE ONLY IF NECESSARY(TYPICALLY IF TREE IS GREATERTHAN 4 FEET TALL)BACKFILL WITH NATIVE SOILONLY, COMPACT MODERATELYBY HANDPLACE TOP OF ROOTBALL 1 INCHABOVE THE LEVEL OF NATIVE SOIL.BEFORE MULCH, POTTING SOILSHOULD BE VISIBLE2 INCH DEPTH MEDIUM BARKMULCH NOT TOUCHING STEMTREE TIE SHALL NOT CONSTRICTTREE DEVELOPMENTNATIVE SOILCUT CIRCLING ROOTS ANDSPREAD OR "BUTTERFLY"ROOTBALLBACKFILL WITH NATIVE SOILONLY, COMPACT MODERATELYBY HANDPLACE TOP OF ROOTBALL 1 INCHABOVE THE LEVEL OF NATIVE SOIL.BEFORE MULCH, POTTING SOILSHOULD BE VISIBLE2 INCH DEPTH MEDIUM BARKMULCH NOT TOUCHING STEMNATIVE SOILCUT CIRCLING ROOTS ANDSPREAD OR "BUTTERFLY"ROOTBALLSTAKE ONLY IF NECESSARY(TYPICALLY IF TREE IS GREATERTHAN 4 FEET TALL)TREE TIE SHALL NOT CONSTRICTTREE DEVELOPMENTSTAKE TREE AT 1/3 HEIGHT OFTREE, USE "TREE TIES" ORENGINEER APPROVEDEQUIVALENT, REMOVE STAKEAND TIE AFTER 1 YEARREST BOTTOM OF ROOTBALL ONUNDISTURBED NATIVE SOILSPREAD A 3 FOOT MINIMUMDIAMETER MULCH RING(DONUT) AROUND THEPLANTING HOLEWIDTH OF PLANTINGHOLE SHALL 3'' WIDER AND 2"DEEPER THAN ROOTBALLREST BOTTOM OF ROOTBALL ONUNDISTURBED NATIVE SOILSPREAD A 3 FOOT MINIMUMDIAMETER MULCH RING(DONUT) AROUND THEPLANTING HOLEWIDTH OF PLANTINGHOLE SHALL 3'' WIDER AND 2"DEEPER THAN ROOTBALLTREE AND SHRUB PLANTING AND STAKING DETAIL1 2/22/19 CJ City of Auburn Comments 10/19/18 2 4/5/19 CJ City of Auburn Comments 3/28/18 EXHIBIT 7EXHIBIT 2 Environmental ConsultantsPROJECT: CLIENT: NONE SCALE DRAWN BY: CHECKED BY: DESIGNED BY: 3 of 3 SHEET APPROVED BY: DATE: CONSULTANT: Wetlands, Streams, and Wildlife J. S. Jones and Associates, Inc. P.O. BOX 1908 ISSAQUAH, WASHINGTON 98027 Jeff Jones Jeff Jones NO. DATE BY REVISION1.0 Executive SummaryThe applicant proposes to plat the subject parcels into single-family lots. Mullens Creek isa Class III stream, according to Auburn Municipal Code 16.10.080. The minimum bufferrequirement is 25 feet for Class III streams, according to Auburn Municipal Code 16.10.090. Thewetlands on-site are Category III wetlands and have a buffer requirement of 25 to 50 feet,according to Auburn Municipal Code 16.10.090. The buffer area will be enhanced with nativevegetation and placed in a native growth protection tract. The recommended buffer is 25 feet.1.1 Goals and ObjectivesThe goal of mitigation is to increase the functions and values of the existing critical area bufferthrough enhancement. In its current degraded state, the critical area buffer does not provide thefunctions necessary to adequately protect the wetland. The objectives necessary to meet the abovestated goal area as follows:·Restore the buffer to a native plant community·Protect the Buffer from future impacts by fencing, signage and a notice on title·Maintain and monitor the enhancement area for a period of five years or until the site meetsthe specified performance standards·If the enhancement area fails to meet performance standards provide a contingency plan torectify the situation2.0 Project LocationThe property is King County Tax Parcel No.'s 022104-9044 & 22104-9071. Located at 29241 &29255 59th Ave. S., Auburn, Washington 98001.3.0 Responsible PartiesProperty OwnersSound Built DevelopmentP.O. Box 73790Puyallup, WA 98371John Harknessjohn@soundbuilthomes.com253-677-9234Environmental ConsultantJ. S. Jones and Associates, Inc.Attn: Jeffery S. Jones, PWSP.O. Box 1908Issaquah, Washington 98027253-905-57364.0 StandardsAll work and materials shall conform to the City of Auburn standards and specifications, and tothe specifications and details shown on these plans.5.0 City of Auburn ContactCertain actions within this mitigation/restoration plan require inspection or approval by City ofAuburn staff. Requests for inspection/approval shall be coordinated with the City of Auburn.6.0 Contractor InformationWhen it is available, contact information shall be provided to the City of Auburn that includesnames, addresses and phone numbers of persons/firms that will be responsible for grading themitigation/restoration area, installing required plants, and performing required maintenance andmonitoring.7.0 Contractor's QualificationsContractor/Landscape Installer must be experienced in mitigation and restoration work. ThePermittee shall provide that there is one person on the site at all times during work and installationwho is thoroughly familiar with the type of materials being installed and the best methods for theirinstallation, and who shall direct all work being performed under these specifications. This personshall be experienced in installing native plant materials for wetland mitigation or restorationprojects, unless otherwise allowed by the Wetland Scientist and/or City of Auburn staff .8.0 Site ConditionsThe Permittee and/or Wetland Scientist shall immediately notify City of Auburn staff of anydiscrepancies between these plans and the site conditions. The locations of plants shown may bemodified in the field by the Wetland Scientist and/or City of Auburn staff based on fieldconditions at the time of planting. Changes should be documented and as-built drawingssubmitted to City of Auburn upon request for formal construction approval.9.0 Plants9.1 Origin: Plant materials shall be Northwest native plants, nursery grown in the Puget Soundregion of Washington. Dug plants may only be used upon approval of City of Auburn staff.9.2 Handling: Plants shall be handled so as to avoid all damage, including breaking, bruising,root damage, sunburn, drying, freezing or other injury. Plants must be covered during transport.Plants shall not be bound with wire or rope in a manner that could damage branches. Protect plantroots with shade and wet soil in the time period between delivery and installation. Do not liftcontainer stock by trunks, stems, or tops. Do not remove from containers until ready to plant.Water all plants as necessary to keep moisture levels appropriate to the species horticulturalrequirements. Plants shall not be allowed to dry out. All plants shall be watered thoroughlyimmediately upon installation. Soak all containerized plants thoroughly prior to installation. Bareroot plants are subject to the following special requirements, and shall not be used unless plantedbetween November 1 and March 1, and only with the permission of the Wetland Scientist and Cityof Auburn staff. Bare root plants must have enough fibrous root to insure plant survival. Rootsmust be covered at all times with mud and/or wet straw, moss, or other suitable packing materialuntil time of installation. Plants whose roots have dried out from exposure will not be accepted atinstallation inspection.9.3 Storage: Plants stored by the Permittee for longer than one month prior to planting shall beplanted in nursery rows, and treated in a manner suitable to that species horticultural requirements.Plants must be inspected by the Wetland Scientist prior to installation.9.4 Damaged Plants: Damaged, dried out, or otherwise mishandled plants will be rejected atinstallation inspection. All rejected plants shall be immediately removed from the site.9.5 Plant Names: Plant names shall comply with those generally accepted in the native plantnursery trade. Any questions regarding plant species or variety shall be referred to the WetlandScientist or City of Auburn staff. All plant materials shall be true to species and variety.9.6 Plant Substitutions: Plant substitutions are not permitted without the permission of theWetland Scientist and/or City of Auburn staff. Same species substitutions of larger size do notrequire special permission. However, small plants often experience less transplant shock andadapt more quickly to site conditions, resulting in a higher success rate. As such, smaller plantswill be approved as substitutions based on certain site-specific conditions (trees not less than 1gallon size however).9.7 Quality and Condition: Plants shall be normal in pattern of growth, healthy, well-branched,vigorous, with well-developed root systems, and free of pests and diseases. Damaged, diseased,pest-infested, scraped, bruised, dried-out, burned, broken, or defective plants will be rejected.Plants with pruning wounds over 1" in diameter will be rejected.9.8 Roots: All plants shall be balled and burlapped or containerized, unless authorized by theWetland Scientist. Rootbound plants or B&B plants with damaged, cracked or loose rootballs(major damage) will be rejected. Immediately before installation, plants with minor root damage(some broken and/or twisted) must be root-pruned. Matted or circling roots of containerizedplantings must be pruned or straightened and the sides of the root ball must be roughened from topto bottom to a depth of approximately half and inch in two to four places. Bare root plantings ofwoody material is allowed only with permission from the Wetland Scientist, and/or City ofAuburn staff.9.9 Sizes: Plant sizes shall be the size indicated in the plant schedule. Larger stock may beacceptable provided that it has not been cut back to size specified, and that the root ball isproportionate to the size of the plant. Smaller stock may be acceptable, and under somecircumstances preferable, based on site-specific conditions. Measurements, caliper, branching andballing and burlap shall conform to the American Standard of Nursery Stock by the AmericanAssociation of Nurserymen (latest edition).9.10 Form: Evergreen trees, if used, shall have single trunks and symmetrical, well-developedform. Deciduous trees shall be single-trunked unless specified as multi-stem in the plant schedule.Shrubs shall have multiple stems, and be well-branched.9.11 Planting: Planting shall be done in accordance with illustrated details in themitigation/restoration plan set and accepted industry standards.9.12 Timing of Planting: Unless otherwise approved by City of Auburn staff, all planting shalloccur between September 1 and March 31.9.13 Weeding: Existing and exotic vegetation in the mitigation and buffer areas will be handweeded from around all newly installed plants at the time of installation and on routine basisthrough monitoring period. No chemical control of vegetation on any portion of the site isallowed without the written permission of City of Auburn staff.9.14 Soil Amendments: Unless otherwise specified and approved by City of Auburn, native soilwill be incorporated into the planting pits. Soil in the buffer enhancement area will be amended tocontain 20% organic soil in the entire buffer area.9.15 Mulch: The soil surface surrounding all planting pit areas shall receive no less than 2"-4"of organic compost or medium bark mulch after planting. Compost or mulch shall be kept wellaway (at least 2") from the trunks and stems of woody plants. Compost shall be Cedar Grove PureCompost or approved equal.9.16 Site Conditions: Contractor shall immediately notify the Wetland Scientist of drainage orsoil conditions likely to be deterimental to the growth or survival of plants. Planting operationsshall not be conducted under the following conditions: freezing weather, when the ground isfrozen, excessively wet weather, excessively windy weather, or in excessive heat.9.17 Plant Locations: Locations shall be as depicted in the approved plan set. The LandscapeDesigner and/or Wetland Scientist may change the locations of plantings shown on plans based onfield conditions.9.18 Planting in Pits: Planting pits shall be circular or square with vertical sides, and shall be 3"deeper and 6" larger in diameter than the root ball of the plant. Break up the sides of the pit incompacted soils. Set plants upright in pits, as illustrated in planting detail. Burlap shall beremoved from the planting pit. Backfill shall be worked back into holes such that air pockets areremoved without adversely compacting soils.9.19 Fertilizer: Slow release fertilizer may be used if pre-approved by City of Auburn staff.Fertilizers shall be applied only at the base of plantings underneath the required covering of mulch(that does not make contact with stems of the plants). No fertilizers will be placed in plantingholes.9.20 Water: Plants shall be watered upon completion of backfilling. For spring plantings (ifapproved), a rim of earth shall be mounded around the base of the tree or shrub no closer than thedrip line, or no less than 30" in diameter, except on steep slopes or in hollows. Plants shall bewatered a second time within 24-48 hours after installation. The earthen rim/dam should beleveled prior to the second growing season.10.0 Grass SeedingSeeding is required as described in approved plans. Use specified native mix at rate specified. Allseed materials shall be free of weed seeds or other foreign matter detrimental to plant growth.10.1 Timing: Seeding shall not take place until mulch has been applied. Contractor shall insurethat areas to receive seed are clean of debris and that final grades are correct. Seeding shall beperformed after other plant installation is complete. Seeding is the final step of the intialinstallation; site shall be closed to all vehicles and foot traffic shall be minimized after seeding iscomplete. Seeding shall not take place when the ground is frozen or in windy weather. Seedsshall be hand broadcast or by mechanical hand powered spreader, with as even distribution asfeasiable. Areas within 6"-12" of stems of installed plants shall not be seeded. 11.0 MaintenanceMaintenance shall be required in accordance with City of Auburn guidelines and approved plans.11.1 Survival: The Permittee shall be responsible for the health of 100% of all newly installedplants for one growing season after installation has been accepted by City of Auburn staff (seePerformance Standards). A growing season for these purposes is defined as occurring from springto spring (March 15 to March 15, following year). For fall installation (often required), thegrowing season will begin the following spring. The Permittee shall replace any plants that arefailing, weak, defective in a manner of growth, or dead during this growing season, as directed bythe Landscape Designer, Wetland Scientist, and/or City of Auburn staff.11.2 Installation Timing for Replacement Plants: Replacement plants shall be installedbetween September 1 and March 31, unless otherwise determined by the Landscape Designer,Wetland Scientist, and/or City of Auburn staff.11.3 Duration and Extent: In order to achieve performance standards, the Permittee shall havethe mitigation/restoration area maintained for the duration of the monitoring period, 3 years.Maintenance will include watering, weeding around base of installed plants, pruning, replacement,re-staking, removal of all classes of noxious weeds (see Washington State Noxious Weeds List,WAC 16-750-005) as well as Himalayan blackberry, and any other measures needed to insureplant survival. All maintenance shall be directed by the Wetland Scientist.11.4 Standards for Replacement Plants: Replacement plants shall meet the same standards forsize and type as those specified for original installation unless otherwise directed by theLandscape Designer, Wetland Scientist, and/or City of Auburn staff. Replacement plants shall beinspected as described above for the original installation.11.5 Replanting: Plants that have settled in their planting pits too deep, too shallow, loose, orcrooked shall be replanted as directed by the Wetland Scientist, and/or City of Auburn staff.11.6 Herbicides/Pesticides: Chemical controls shall not be used in the mitigation/restorationarea, sensitive areas or their buffers. However, limited use of herbicides may be approveddepending on site specific conditions, only if approved by City of Auburn staff.11.7 Irrigation/Watering: Water shall be provided during the dry season (July 1-October 15)for the first three years after installation to ensure plant survival and establishment. Water shouldbe provided by a temporary above ground irrigation system and/or water truck. Water should beapplied at a rate of 1" of water two times a week for year 1 and 1" of water one time a week duringyears 2 and 3. The temporary above ground irrigation system will be removed by the end of year5 and before the monitoring is finaled.11.8 General: The Permittee shall include in general maintenance activities the replacement ofany vandalized or damaged signs, habitat features, fences or other structural component of themitigation site.12.0 Performance Standards - Plant Cover and SurvivalPlant survival and cover standards are established to measure mitigation success as follows:Performance StandardsYear 1 Year 2 Year 3 Year 4 Year 5Shrub and Sapling Tree Cover* >10% >15% >20% >20% >25%Shrub and Sapling Tree Survival 100% >90% >80% >80% >80%*Includes beneficial native plants in that category that are naturally recruiting volunteersLess than 10% invasive vegetation during any monitoring event.13.0 MonitoringMonitoring shall be conducted annually for 5 years in accordance with the approvedmitigation/restoration monitoring plan.13.1 Vegetation Monitoring: Sample plots will be established for vegetation monitoring, andphoto-points established from which photos will be taken throughout the monitoring period.Sample plots are the preferred method for vegetation monitoring for this site. No less than four(4) plot will be established in each enhancement area. Permanent plot location(s) must beidentified on mitigation/restoration site plans in the first monitoring report (they may be drawn onapproved mitigation/restoration plans by hand). Plots shall detail herb, shrub, and tree aerialcover at radii of 1m, 5m, and 10m respectively, using the Braun-Blanquet releve method or otheracceptable field method. Monitoring of vegetation plots shall occur annually between August 1and September 30 (prior to leaf drop), unless otherwise specified.13.2 Photopoints: No less than one (1) permanent photo point per plot will be established withinthe mitigation/restoration area. Photographs will be taken from these points to visually record thecondition of the mitigation/restoration area. Photos shall be taken annually between August 1 andSeptember 30 (prior to leaf drop), unless otherwise specified.13.3 Reports: Monitioring reports shall be submitted by December 31 of each year during themonitoring period. As applicable, monitoring reports must include description/data for:i.Site plan and location mapii.Historic description of project, including date of installation, current year of monitoring,restatement of mitigation/restoration goals, and performance standardsiii.Plant survival, vigor, and aerial coverage from every plant community (transect data), andexplanation of monitoring methodology in the context of assessing performance standardsiv.Site hydrology, including extent of inundation, saturation, depth to groundwater, function ofany hydrologic structures, piezometer or staff guage if available, inputs, outlets, etc.v.Slope condition, site stability, any structures or special featuresvi.Buffer conditions, e.g. surrounding land use, use by humans, wild and domestic creaturesvii.Observed wildlife, including amphibians, avians and othersviii.Assessment of nuisance/exotic biota and recommendations for managementix.Soils, including texture, Munsell color, rooting and oxidized rhizoshperesx.Receipts for off-site disposal of any dumping, weeds, or invasive plantsxi.Receipts for any structural repair or replacementxii.4"x6" color photograph taken from permanent photo-points as shown onMonitoring/Restoration plan.xiii.Summary of maintenance and contingency measures proposed for next season and completedfor past season13.4 Deficiences: Any deficiency discovered during any monitoring or inspection visit must becorrected within 60 days of approval by City of Auburn.13.5 Contingency Plan: Should any monitoring report reveal the mitigation has failed in wholeor in part, and should that failure be beyond the scope of routine maintenance, a Contingency Planwill be submitted. The Contingency Plan may range in complexity from a list of plantssubstituted, to cross-sections of proposed engineered structures. Once approved, it may beinstalled, and will replace the approved mitigation/restoration plan. If the failure is substantial, theCity of Auburn may extend the monitoring period for that mitigation.14.0 BondPrior to beginning any work, the Permittee must provide a mitigation/restoration bond orassignment of funds per City of Auburn procedures. Upon approval of the mitigation plan, a bondquantity worksheet will completed based on all elements of the mitigation/restoration plan.15.0 ProtectionThe buffer enhancement area will be placed in a native growth protection easement.16.0 As-built ReportsAn as-built report will be provided to the City of Auburn within 30 days of the completion ofinstallation of the buffer enhancement plan.Conceptual Buffer Enhancement Plan Sound Built Development P.O. Box 73790, Puyallup, WA 98371 West Hills Plat 29241 & 29255 59th Ave. S., Auburn, Washington 98001 9/17/2018PROJECT REF: _________________________THESE PLANS ARE APPROVED FORCONFORMANCE WITH THE CITY OF AUBURN’SPLANNING DEPARTMENT REQUIREMENTS.APPROVED BY: _________________________DATE APPROVED: ______________________1 2/22/19 CJ City of Auburn Comments 10/19/18West Hills Plat Conceptual Buffer Enhancement Plan29241 & 29255 59th Ave. S., Auburn, Washington 98001Parcel No.'s 022104-9044 & 22104-90712 4/5/19 CJ City of Auburn Comments 3/28/18 EXHIBIT 7EXHIBIT 7 1 Addendum to the Critical Area Study West Hills Plat 29241 & 29255 59th Ave. S. Auburn, Washington Tax Parcel Numbers: 022104-9044 & 9071 Southwest 1/4 of Section 2, Township 21 N, Range 4 E of the Willamette Meridian Prepared for: Sound Built Development P.O. Box 73790 Puyallup, WA 98371 Evan Mann Entitlement Manager SoundBuilt Homes 253.820.7835 evan@soundbuilthomes.com Dated: September 6, 2019 Prepared by: Jeffery S. Jones, Wetland Scientist & Wildlife Biologist EXHIBIT 7 Project Description The applicant proposes to plat the subject parcels into single-family lots. A Critical Area Study was conducted to determine the type and extent of wetlands and streams on and near the site. Stream Classification Karen Walter, Muckleshoot Fisheries Biologist, reviewed the SEPA checklist and provided comments. Her first comment was regarding the stream classification of Mullens Creek. The Salmonscape mapping, provided by Karen Walter, identifies all the Mullens Creek tributaries as having documented fish presence. However, there is no information about sampling or observations that document fish presence above the valley floor. About fifteen years ago, I walked the subject tributary upstream from the Litowitz property on S. 287th St. Above the valley floor, the stream channel gradient is 20-30%, with at least several sections exceeding 30%. The sections exceeding 30% are natural barriers to fish passage. There is over 1,200 feet of continuously steep gradient. Larry Fisher, the regional WDFW biologist, has been contacted to find out what he knows about fish presence in the subject stream. However, he has not replied as of the date of this report. It is extremely unlikely that coho are present in Mullens Creek at the subject site. The natural stream channel gradient downstream has sections that exceed a 30% gradient, which is are too steep for fish passage. Artificial barriers such as the culvert at 59th Ave. S. can be replaced with fish passage culverts and therefore are not used to make a determination of no fish presence. Project Impacts A critical area impact analysis will be prepared that addresses the code requirements for mitigation sequencing and a net effect on wetland and stream functions. It is our belief that the stream and wetland functions will increase with buffer enhancement, because the existing buffer is dominated by invasive plants. A tree inventory will be included in the impact analysis. Stormwater treatment will be addressed by the civil engineer. EXHIBIT 7 King C oun ty Date : 9/6/201 9 Notes: ±The informati on included on this map has been compi led by King County staff from a variety of sour ces and issubject to change wi thout notice. King County makes no r epresentati ons or w ar ranties, expr ess or impl ied,as to accurac y, completenes s, timeli ness , or ri ghts to the use of such infor mation. This document is not intendedfor use as a s urvey pr oduct. King County shall not be liable for any gener al, s pecial, i ndir ect, incidental , orconsequential damages incl uding, but not li mited to, lost revenues or lost pr ofits resulting fr om the use or misuseof the information contained on this map. Any sale of this map or infor mati on on this map is pr ohibited except bywritten per mi ssi on of Ki ng County. Mul le ns Cr eekEXHIBIT 7 EarthSolutionsNWLLC EarthSolutions NW LLC Geotechnical Engineering Construction Observation/Testing Environmental Services 1805 -136th Place N.E.,Suite 201 Bellevue,WA 98005 (425)449-4704 Fax (425)449-4711 www.earthsolutionsnw.com GEOTECHNICAL ENGINEERING STUDY PROPOSED WEST HILL RESIDENTIAL PLAT 29255 &29241 -59 AVENUE SOUTH AUBURN,WASHINGTON ES-6095 TH EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 Geotechnical Engineering,Construction Observation/Testing and Environmental Services Drwn.CAM Checked SES Date July 2018 Date 07/20/2018 Proj.No.6095 Plate 1 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Vicinity Map West Hill Auburn,Washington Reference: King County,Washington Map 745 By The Thomas Guide Rand McNally 32nd Edition NORTH NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. SITE EXHIBIT 8 Plate Proj.No. Date Checked By Drwn.ByEarthSolutionsNWLLCGeotechnicalEngineering,ConstructionObservation/TestingandEnvironmentalServicesEarthSolutionsNWLLCEarthSolutionsNWLLC58thavenues.s.294th street 59thavenues.350350 340 340 330 330 320 320 12345 6 7 8 9 10 11 12131415 16 17 18 19 Tract A Access Tract B Storm Tract D Critical Area TP-1 TP-2 TP-3 TP-4 TP-5 TP-6 TP-7 TP-8 NOTE:This plate may contain areas of color.ESNW cannot be responsible for any subsequent misinterpretation of the information resulting from black &white reproductions of this plate. NOTE:The graphics shown on this plate are not intended for design purposes or precise scale measurements,but only to illustrate the approximate test locations relative to the approximate locations of existing and /or proposed site features.The information illustrated is largely based on data provided by the client at the time of our study.ESNW cannot be responsible for subsequent design changes or interpretation of the data by others. LEGEND Approximate Location of ESNW Test Pit,Proj.No. ES-6095,July 2018 Subject Site Proposed Lot Number TP-1 NORTH 0 4 0 8 0 1 6 0 Sc ale in Feet1"=8 0 ' 16 CAM SES 07/20/2018 6095 2TestPitLocationPlan WestHillAuburn,WashingtonEXHIBIT 8 Drwn.CAM Checked SES Date July 2018 Date 07/20/2018 Proj.No.6095 Plate 3 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Geotechnical Engineering,Construction Obser vation/Testing and Environmental Services Retaining Wall Drainage Detail West Hill Auburn,Washington NOTES: Free-draining Backfill should consist of soil having less than 5 percent fines. Percent passing No.4 sieve should be 25 to 75 percent. Sheet Drain may be feasible in lieu of Free-draining Backfill,per ESNW recommendations. Drain Pipe should consist of perforated, rigid PVC Pipe surrounded with 1-inch Drain Rock. LEGEND: Free-draining Structural Backfill 1-inch Drain Rock 18"Min. Structural Fill Perforated Rigid Drain Pipe (Surround in Drain Rock) SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAWING EXHIBIT 8 Drwn.CAM Checked SES Date July 2018 Date 07/20/2018 Proj.No.6095 Plate 4 Earth Solutions NWLLCEarthSolutionsNWLLC EarthSolutions NW LLC Geotechnical Engineering,Construction Observation/Testing and Environmental Services Footing Drain Detail West Hill Auburn,Washington Slope Perforated Rigid Drain Pipe (Surround in Drain Rock) 18"Min. NOTES: Do NOT tie roof downspouts to Footing Drain. Surface Seal to consist of 12"of less permeable,suitable soil.Slope away from building. LEGEND: Surface Seal:native soil or other low-permeability material. 1-inch Drain Rock SCHEMATIC ONLY -NOT TO SCALE NOT A CONSTRUCTION DRAW ING EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 EXHIBIT 8 PRELIMINARY STORMWATER REPORT FOR WEST HILL PLT18‐00047 CITY OF AUBURN IN KING COUNTY, WASHINGTON Project Manager: Lafe Hermansen Prepared by: Sheri Murata, P.E. Date: July 30, 2018 Revised: Sept 25, 2018, Feb 22, 2019, June 28, 2019 Core No.: 18069 6/28/19 EXHIBIT 9 Core Design, Inc. WEST HILL i Contents 1. PROJECT OVERVIEW ................................................................................................................................... 1 Figure 1‐1: Vicinity Map ............................................................................................................................. 1 Table 1‐1 Parcel Information...................................................................................................................... 1 Figure 1‐2: Site Map and Grading Plan ...................................................................................................... 3 2. EXISTING CONDITIONS SUMMARY ............................................................................................................. 4 Figure 2‐1: Drainage Complaints ................................................................................................................ 5 Table 2‐1 Drainage Complaints .................................................................................................................. 5 Figure 2‐2: Existing Conditions Summary Site Map ................................................................................... 7 Figure 2‐3: FIRM Map ................................................................................................................................. 8 3. OFF‐SITE ANALYSIS ..................................................................................................................................... 9 Figure 3‐1: Downstream Drainage Exhibit ............................................................................................... 16 Figure 3‐2 Offsite Drainage System Table ................................................................................................ 17 4. PERMANENT STORMWATER CONTROL PLAN .............................................................................................. 18 4.1 Threshold Discharge Areas ........................................................................................................................ 18 Table 4‐1 Threshold Discharge Area ........................................................................................................ 18 4.2 Pre‐Developed Site Hydrology ................................................................................................................... 19 4.3 Developed Site Hydrology ......................................................................................................................... 19 Table 4‐2 – Developed Areas to Vault ...................................................................................................... 19 Table 4‐3 – Area Bypassing Vault ............................................................................................................. 20 4.3 Performance Standards and Goals ............................................................................................................ 20 4.4 Flow Control ............................................................................................................................................... 21 4.5 Water Quality System ................................................................................................................................ 22 4.6 Conveyance System Analysis and Design .................................................................................................. 23 4.7 Managing Stormwater in Wetlands ........................................................................................................... 23 Table 4‐4 – Wetland Recharge (Existing Conditions) ............................................................................... 26 Table 4‐5 – Wetland Recharge (Developed Conditions) .......................................................................... 26 Figure 4‐1: Existing Basin Map ................................................................................................................. 28 Figure 4‐2: Developed Basin Map ............................................................................................................ 29 Figure 4‐3: Storm System Profile ............................................................................................................. 30 5. DISCUSSION OF MINIMUM REQUIREMENTS ............................................................................................... 31 EXHIBIT 9 Core Design, Inc. WEST HILL ii APPENDIX ATTACHMENT A – OPERATION AND MAINTENANCE (O & M) MANUAL (PROVIDED DURING FINAL ENGINEERING) ATTACHMENT B – CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN (PROVIDED DURING FINAL ENGINEERING) ATTACHMENT C – HYDRAULIC/HYDROLOGIC ANALYSIS WWHM Vault Sizing Wetland Recharge Analysis Modular Wetland Detail ATTACHMENT D – OTHER SPECIAL REPORTS (UNDER SEPARATE COVER) GEOTECHNICAL REPORT CRITICAL AREAS REPORT ARBORST REPORT ATTACHMENT E – DECLARATION OF COVENANT FOR PRIVATELY MAINTAINED FACILITIES (PROVIDED DURING FINAL ENGINEERING) EXHIBIT 9 Core Design, Inc. WEST HILL 1 1. PROJECT OVERVIEW This project proposes to construct 18 single family lots with associated roadway, curb, gutter, sidewalk, utilities, open space, and stormwater management on the site. Half street frontage improvements will be completed on S 294th Street and 59th Avenue S. Multiple permits will be required by the City of Auburn, including, but not limited to; Building, Grading, Land Clearing, Right‐of‐Way Use, and Utility permits. A Level 3 Storm Permit will be required, and this project will need to meet Minimum Requirements 1‐10. The project site is located at S 294th Street and 59th Avenue S. Specifically, the project is in the southeast quarter of the northwest quarter of Section 2, Township 21 north, Range 4, W.M. (See Figure 1‐1: Vicinity Map below). The King County tax parcel ID numbers for the two parcels involved in this project are listed in Table 1‐1 below. Figure 1‐1: Vicinity Map Table 1‐1 Parcel Information South 022104‐9044 103,956 sf North 022104‐9071 103,946 sf TOTAL 207,902 sf The current land‐use is single family residential and is within the R5 (Residential 5 DU/Acre) zone. The total site area is 4.77 acres. This project proposes to develop 3.45 acres and place the remaining 1.32 EXHIBIT 9 Core Design, Inc. WEST HILL 2 acres, including the existing onsite wetland and buffer, will be in an open space tract. All of the existing structures will be demolished. The project site resides within the Duwamish‐Green River watershed, and locally within the Lower Green River West Drainage Basin. Proposed conveyance improvements include storm pipes and catch basins within proposed right of way and replacing existing infrastructure in the frontage streets. The storm drain will be designed according to February 2018 City of Auburn Engineering Design Standards and Supplemental Manuals to the Ecology Stormwater Management Manual for Western Washington. Flow Control will be provided by a detention vault and water quality treatment will be provided by a Modular Wetland downstream of the detention vault discharging to 59th Avenue S. Refer to Figure 1‐2 – Site Map and Grading Plan. EXHIBIT 9 EXHIBIT 9 Core Design, Inc. WEST HILL 4 2. EXISTING CONDITIONS SUMMARY The South parcel has an existing one‐story residence with a daylight basement, carport and asphalt driveway off of 59th Avenue S and one accessory structure in the backyard. There is lawn in a “U” shaped area in the backyard in between the house and the accessory structure with the remaining area forested. The North parcel has an existing two‐story residence, carport and asphalt driveway off of 59th Avenue S and three accessory structures in the backyard. Like the South parcel, there is lawn in between the house and accessory structures with the remaining area forested. Refer to the Existing Conditions Summary Site Map and the end of this section. Existing Utilities Existing onsite utilities include water, gas, power, and septic systems. Both frontage streets have water, sewer, and storm mains. In addition, 59th Avenue S also has gas and overhead power. Drainage Patterns Both parcels drain to the west and north wetland at about 8 percent in flatter areas and up to 28 percent as you approach the wetland and Mullen Slough. About a third of the site also drains to the east at about 8 percent toward 59th Avenue S. Drainage Issues The ravine downstream of the project site has known drainage issues, so a qualitative downstream analysis has been requested by the City and is provided in Section 3. Other drainage complaints on record per King County iMap are shown in Figure 2‐1. EXHIBIT 9 Core Design, Inc. WEST HILL 5 Figure 2‐1: Drainage Complaints Table 2‐1 Drainage Complaints Complaint No. Complaint Date Closed 1979‐0051 Runoff/west valley heights area 8/16/79 2005‐0390 Sewer/septic pipe outlets into ditch? Investigation found new brick wall with 4" flex pipe leading out to ditch. Pipe appears to be storm drain outlet for wall 8/10/05 1998‐0826 Channel erosion impact retaining wall 1/10/99 1981‐0087 Drainage 11/24/81 Sensitive Areas There is a wetland on the west side of both properties and another wetland on the north side of the North parcel. Mullen Slough/Tributary 0045 flows north through both wetlands on the adjacent parcel to the west and continues east north of the North parcel and crosses under 59th Avenue S. There are no erosion, landslide, seismic or coal mine hazards on site. Environmental Issues There are no known fuel tanks on site, groundwater wells within 100 feet of the site or basin plans. This project is not in an aquifer recharge area nor is there any Superfund sites in the vicinity. Geotechnical Report A Geotechnical Engineering Study was completed by Earth Solutions NW, LLC on July 24, 2018 and revised on September 12, 2018. Per their report, the site generally consists of topsoil in the upper 3 to 2005‐0390 1998‐0826 PROJECT SITE 1979‐0051 1981‐0087 EXHIBIT 9 Core Design, Inc. WEST HILL 6 12 inches, with native soils consisting primarily of silty sand or glacial till. The upper, medium dense deposits were characterized as “weathered”, and the lower, dense to very dense deposits were characterized as “unweathered” or “hardpan”. FEMA 100‐year Flood Plain Map According to FEMA Map # 53033C1235F (dated May 16, 1995); the site is not located within a 100‐year floodplain. Refer to Figure 2‐3 Flood Insurance Rate Map included at the end of this chapter. EXHIBIT 9 EXHIBIT 9 EXHIBIT 9 Core Design, Inc. WEST HILL 9 3. OFF‐SITE ANALYSIS A level 2 downstream analysis was performed on the project site. All related tasks are addressed below. A field investigation was completed on July 10, 2018. The weather conditions were mostly sunny and approximately 75 degrees Fahrenheit. Upstream Tributary Analysis A negligible amount of overland flow would enter the site from the properties to the south during a storm event. Downstream Analysis A Level 2 downstream analysis was performed on the project site. The site currently contains two existing houses near the east property line with paved driveways connecting to 59th Avenue S to the east. There are several other small shed structures on the eastern half of the site. A portion of the eastern part of the site is covered by grass while the rest of the site is covered with trees and overgrown blackberry bush. A wetland exists on the west half of the site and near the north property line. The site slopes generally to the north and east, and all stormwater drainage on site will flow either to the storm system along the frontage to the east or into the stream at the north property line flowing east. The stream is known as Mullen Slough. Both drainage paths meet up within ¼ mile downstream of the site, so the site is considered to have a single drainage basin, however to this analysis the two main drainage paths will be labeled A and B. Refer to the Downstream Drainage Exhibit for a visual representation of the on‐site drainage. The entire property is located within the Lower Green River West basin. Drainage A: Most of the north parcel and the western half of the south parcel slopes to the north and northwest towards the wetlands and stream that exist on site. The stream travels north just west of the property and crosses through the northwest corner of the site. The stream continues east at this point and meanders near the north property line. The stream on site is heavily overgrown with vegetation. The stream on the property has a width of 2‐3 feet and is flowing about one inch deep. After leaving the property in the center of the north property line, the stream continues in a northeasterly direction until reaching the ditch along the west side of 59th Avenue S. The stream continues northeast through a 24‐ inch CMP culvert under 59th Avenue S and daylights into a channel on a property on the east side of 59th Avenue S. This channel is well‐defined and lined with rocks. The channel has a width of 4 feet with banks 3 feet high. The stream is flowing 2‐3 inches deep and the streambed contains gravel and cobblestones up to 2 inches in diameter, with several boulders throughout the channel. There is no sand or silt found in the channel and no evidence of erosion or flooding was found. The channel continues northeast through the property until reaching an 18‐inch CMP culvert that continues underground and outfalls into a ravine northeast of the property. The ravine is deep and steeply banked, with banks as high as 20 feet and slopes over 40%. The stream at the bottom of the ravine is inaccessible due to the steepness of the banks. The banks appear to be stable with vegetation all along the ravine. There is some evidence of scouring at the bottom of the ravine that extends about 4 feet vertically. The stream continues through EXHIBIT 9 Core Design, Inc. WEST HILL 10 the ravine in a northeasterly direction and bends to the north before reaching a point greater than ¼ mile downstream of the project site and the analysis is terminated. Drainage B: The eastern third of the site slopes to the east towards 59th Avenue S with gradients up to approximately 10%. At the east property line, the ground slopes significantly down to the street where a shallow swale and associated storm drainage exists. Flow that enters the storm system flows north through a 12‐inch CMP or overland through the swale before daylighting into a ditch on the west side of 59th Avenue S. Stormwater flows north through the ditch for approximately 20 feet before meeting up with the stream from Drainage A and continuing through the culvert underneath 59th Avenue S. Level 2 Downstream Analysis A Level 2 downstream analysis has been requested during a preapplication meeting with the City of Auburn. According to Volume III of the City of Auburn Supplemental Manual, a Level 2 downstream analysis requires a quantitative analysis of the drainage components including non‐survey field data and downstream system capacity calculations. An additional site visit was conducted on July 16, 2018 to collect dimension data at several locations along the drainage path. These locations include the stream on site (Mullen Slough), the downstream rock lined channel, the roadside swale (59th Avenue S), the culvert crossing 59th Ave S, and the ravine that extends beyond ¼ mile offsite. See the tables below for dimension data and the Downstream Drainage Exhibit for locations that dimension data was taken. A uniform flow analysis has been completed below for the flow capacity at each point the dimension data was taken. The downstream ravine was inaccessible due to the steepness of the banks, therefore these measurements are estimates. The uniform flow analysis was completed using Manning’s Equation per the definition provided in the 2012 DOE SMMWW. EXHIBIT 9 Core Design, Inc. WEST HILL 11 Point 1: Mullen Slough Creek Top Width 3’ Creek Bottom Width 2.5’ Creek Depth 1’ Creek Side Slope 1:4 Approximate Slope 2% Bed Lining Small Rocks/Sand Manning’s “n” 0.04 Qൌ1.49 n A Rଶ ଷ S ଵ ଶ S = Slope = 0.02 ft/ft A = Area = 2.75 ft2 P = Wetted Perimeter = 2.5 ൅ 2൫√0.25ଶ ൅1ଶ൯ൌ4.56 R = Hydraulic Radius = A/P = ଶ.଻ହ ସ.ହ଺ ൌ0.60 Flow Capacity Q = 10.3 CFS Length of reach: Stream continues approximately 300 feet offsite until reaching swale (point 2) Capacity of Section = 825 CF Point 2: Swale along 59th Ave S Creek Top Width 7’ Creek Bottom Width 1’ Creek Depth 3’ Creek Side Slope 1:1 Approximate Slope 10% Bed Lining Gravel Manning’s “n” 0.04 Qൌ1.49 n A Rଶ ଷ S ଵ ଶ S = Slope = 0.10 ft/ft A = Area = 12 ft2 P = Wetted Perimeter = 1൅2൫√3ଶ ൅3ଶ ൯ ൌ 9.49 R = Hydraulic Radius = A/P = ଵଶ ଽ.ସଽ ൌ1.16 Flow Capacity Q = 156 CFS Length of Reach: Approximately 50 feet Capacity of Section = 600 CF 1 4 3’ 2.5’ 1 1 1’ 7’ EXHIBIT 9 Core Design, Inc. WEST HILL 12 Point 3: Culvert underneath 59th Ave S Pipe Diameter 24” Depth of stream 3” Approximate Slope 5% Pipe Material CMP Manning’s “n” 0.024 Qൌ1.49 n A Rଶ ଷ S ଵ ଶ S = Slope = 0.05 ft/ft A = Area = 3.14 ft2 P = Wetted Perimeter = 2 ∗ 𝜋 ∗ 1 ൌ 6.28 ft R = Hydraulic Radius = A/P = ଷ.ଵସ ଺.ଶ଼ ൌ0.5 ft Flow Capacity Q = 8.7 CFS Length of Reach: Approximately 35 feet Capacity of Section = 110 CF Point 4: Drainage Channel Creek Top Width 4’ Creek Bottom Width 3’ Creek Depth 3’ Creek Side Slope 1:6 Approximate Slope 5% Bed Lining Medium Rocks Manning’s “n” 0.04 Qൌ1.49 n A Rଶ ଷ S ଵ ଶ S = Slope = 0.05 ft/ft A = Area = 10.5 ft2 P = Wetted Perimeter = 3 ൅ 2൫√3ଶ ൅0.5ଶ ൯ ൌ 9.08 R = Hydraulic Radius = A/P = ଵ଴.ହ ଽ.଴଼ ൌ1.16 Flow Capacity Q = 96.6 CFS Length of Reach: Approximately 200 feet Capacity of Section = 2100 CF 1 6 3’ 4’ EXHIBIT 9 Core Design, Inc. WEST HILL 13 Point 5: Downstream Ravine Creek Top Width 5’ Creek Bottom Width 5’ Creek Depth 4’ Creek Side Slope Vertical Approximate Slope 15% Bed Lining Cobbles with large boulders Manning’s “n” 0.05 Qൌ1.49 n A Rଶ ଷ S ଵ ଶ S = Slope = 0.15 ft/ft A = Area = 20 ft2 P = Wetted Perimeter = 5 + 4 + 4 = 13 ft R = Hydraulic Radius = 20/13 = 1.54 Flow Capacity Q = 308 CFS Length of Reach: Continues offsite further than ¼ mile 1 –Mullen Slough crossing through the property near the northwest corner facing northeast. 2 –– Shallow swale along frontage on west side of 59th Avenue S, facing north. 4’ 5’ EXHIBIT 9 Core Design, Inc. WEST HILL 14 3 – Looking west at vegetation covering Mullen slough, from point where stream and swale intersect. 4 – Swale on west side of 59th Avenue S looking north. 5 – Looking northeast at stream flowing through neighboring property northeast of site. 6 ‐ Looking northeast at stream flowing through neighboring property northeast of site. EXHIBIT 9 Core Design, Inc. WEST HILL 15 7 – Looking back at outfall into ravine, pipe facing northeast. 8 – Facing northwest, looking down into ravine. Stream is flowing to northeast. EXHIBIT 9 Pictometry, King County, King County Downstream Drainage Exhibit Date: 7/17/2018 Notes: ±The information included on this map has been compiled by King County staff from a variety of sources and is subject to change without notice. King County makes no representations or warranties, express or implied, as to accuracy, completeness, timeliness, or rights to the use of such information. This document is not intended for use as a survey product. King County shall not be liable for any general, special, indirect, incidental, or consequential damages including, but not limited to, lost revenues or lost profits resulting from the use or misuse of the information contained on this map. Any sale of this map or information on this map is prohibited except by written permission of King County. EXHIBIT 9 COA Supplemental Manual to the Ecology Stormwater Management Manual for Western Washington Volume I - Minimum Technical Requirements and Site Planning Version 2 31 Off Site Analysis Drainage System Table Basin: Subbasin Name: Subbasin Number: Date: Symbol Drainage Component Type, Size, and Name Description Slope Distance from Site Discharge Existing Problems Potential Problems Observations See Map Type: sheet flow, swale, channel, pipe, pond, flow control/water quality BMP Size: diameter, surface area Drainage basin, vegetation, cover, depth, type of sensitive area, volume % ¼ mile = 1,320 ft. Constrictions, under capacity, ponding, overtopping, flooding, habitat or organism destruction, scouring, bank sloughing, sedimentation, incision, other erosion Tributary area, likelihood of problem, overflow pathways, potential impacts 1Stream (Mullen Slough)3 feet wide Drainage basin consists of mostly dense vegetationand trees, with areas of grass2%-10%25 0' Stream is located within a wetland 0-300 feetSwale along 59th Avenue S10%Sheet flow from eastern portion of site, mostly grass and dense vegetation. Existing storm system daylights into swale (Point 2 on map)Swale is well-defined and lined with rocks, does not appear to present a potential drainage issue59th Ave S Culvert300-600 feetRock-lined, streambed contains cobbles up to 2 " diameter and some boulders5%Ravine600-1320 feetBank sloughing/scouring evident at base of ravineRavine banks contain vegetation thorughout. Banks extend at least 20 feet above stream15%-20%Erosion of banks is possible during extreme storm event. Banks appear stable due to vegetationRavine banks are very steep, stream is inaccesible24" diameter CMP culvert, crosses under 59th Ave S from west to east9.9%Drainage ChannelCrosses through private property300 feetCulvert receives drainage from swale and Mullen Slough. Appears to be in good working condition.EXHIBIT 9 Core Design, Inc. WEST HILL 18 4. PERMANENT STORMWATER CONTROL PLAN Flow Control will be provided by a detention vault such that stormwater discharges shall match developed discharge durations to pre‐developed durations for the range of pre‐developed discharge rates from 50% of the 2‐year peak flow up to the full 50‐year peak flow. Basic water quality treatment will be provided by a Modular Wetland downstream of the vault, sized based on the 2‐year detained flowrate. 4.1 Threshold Discharge Areas Table 4‐1 Threshold Discharge Area Existing Conditions Description On‐Site (sf) Off‐site (sf) Total Total Project Area 207,902 4,700 212,602 Existing Hard Surface 9,888 561 10,449 Existing Native Vegetation 153,129 0 153,129 Existing Lawn 44,885 4,139 49,024 Proposed Conditions Description On‐Site (sf) Off‐site (sf) Total Total Project Area 207,902 4,700 212,602 New Hard Surface 88,369 3,515 91,884 New PGHS 28,870 3,515 32,385 Replaced Hard Surface 9,888 561 10,449 Replaced PGHS 3384 561 3,945 New + Replaced Hard Surface 98,257 4,076 102,333 New + Replaced PGHS 32,254 4,076 36,330 Existing Hard Surface Converted to Vegetation 0 0 0 Land Disturbed 4,700 4,700 Native Vegetation Converted to Lawn 52,112 0 52,112 Native Vegetation Converted to Pasture 0 0 0 Existing Native Vegetation to Remain 57533 0 57,533 Existing Hard Surface to Remain Unaltered 0 0 0 Value of Proposed Improvements 0 Assessed Value of Existing Site Improvements 0 Amount to be graded/filled (cy) 9,000 cy (net cut) 9,000 EXHIBIT 9 Core Design, Inc. WEST HILL 19 4.2 Pre‐Developed Site Hydrology The pre‐developed conditions have been modeled as Till‐Forest. The summarized pre‐developed site hydrology model input is shown below and refer to Figure 4‐1 Existing Basin Map at the end of this section for additional information. 4.3 Developed Site Hydrology The lots have been modeled as 65% impervious with the remaining areas as Till‐Grass. The tract roads have been modeled as 100% impervious and the impervious area with the right‐of‐way was computed in Auto CAD with the remaining areas as Till‐Grass. 0.06 acres of impervious area from 59th Avenue S north of Tract A could not be routed to the detention vault due to topographical constraints, therefore the west half of 59th Avenue S between the Tract A road and S 294th Street will be detained and treated in lieu of this area and it will not be considered bypass. Similarly, 0.03 acres of impervious area currently draining to the Auburn West pond will be swapped for 0.03 acres of new impervious area added on the north side of S 294th Street. The summarized developed site hydrology model input and area summary table is shown below. Refer to Figure 4‐2 Developed Basin Map at the end of this section for additional information. Table 4‐2 – Developed Areas to Vault Lot / Tract # Total Area Land Use Area Impervious Till‐Grass sf acre sf acre sf acre 1 5,586 0.13 3,631 0.08 1,955 0.04 2 4,830 0.11 3,140 0.07 1,691 0.04 3 4,829 0.11 3,139 0.07 1,690 0.04 4 4,579 0.11 2,976 0.07 1,603 0.04 EXHIBIT 9 Core Design, Inc. WEST HILL 20 5 6,667 0.15 4,334 0.10 2,333 0.05 6 6,122 0.14 3,979 0.09 2,143 0.05 7 5,312 0.12 3,453 0.08 1,859 0.04 8 4,954 0.11 3,220 0.07 1,734 0.04 9 4,951 0.11 3,218 0.07 1,733 0.04 10 5,743 0.13 3,733 0.09 2,010 0.05 11 3,461 0.11 3,013 0.07 448 0.01 12 6,502 0.15 4,226 0.10 2,276 0.05 16 600 0.01 500 0.01 100 0.00 17 5,680 0.16 4,423 0.10 1,257 0.03 18 600 0.01 500 0.01 100 0.00 ROW (Ex + Prop) 20,538 0.47 17,154 0.39 3,384 0.00 Tract A 6,767 0.16 6,511 0.15 256 0.00 Tract B 12,962 0.30 1,062 0.02 11,900 0.00 Ex ROW S 294th 1,194 0.03 1,194 0.03 0 0.00 Ex ROW 59th Ave S 2,405 0.06 2,405 0.06 0 0.00 TOTAL to Vault 110,680 2.54 72,376 1.66 38,304 0.88 Table 4‐3 – Area Bypassing Vault ROW Total Area Land Use Area Impervious Till‐Grass sf acre sf acre sf acre Vault Bypass 3,876 0.09 2,705 0.06 1,171 0.03 To Ex Auburn West Pond 1,120 0.03 1,120 0.03 0 0.00 Therefore, the total area to the vault is 2.54 acres with 1.66 acres of impervious and 0.88 acres of Till‐ Grass. Lots 13‐15, Tract D and portions of lot 11, 16‐18 and Tract B will used as wetland recharge and is further discussed in Section 4.7. 4.3 Performance Standards and Goals All stormwater facilities will be designed in accordance with the 2017 City of Auburn Supplemental Manual to the Ecology Stormwater Management Manual for Western Washington and the City of Auburn Engineering and Design Standards. EXHIBIT 9 Core Design, Inc. WEST HILL 21 4.4 Flow Control Flow control is required per Minimum Requirement # 7. The proposed detention vault will be located in the northeast corner of the plat (Tract B) and has a riser height of 4.7 feet. Refer to Figure 1‐2 ‐ Site Map and Grading Plan included at the end of Chapter 1. The The minimum required storage volume is 29,786 cubic feet (at 1oo‐yr water surface elevation). The proposed vault yields a provided live volume of 30,311 cubic feet at elevation 310.00. The outflow from the detention vault control structure releases 0.056 cfs for the 2‐year event, 0.106 cfs for the 10‐year event, and 0.19 cfs for the 100‐year event. These release rates are at or below the pre‐ developed peak flows of 0.076 cfs, 0.155 cfs, and 0.24 cfs for the 2‐year, 10‐year, and 100‐year rates, respectively. EXHIBIT 9 Core Design, Inc. WEST HILL 22 A copy of the full WWHM Report has been included as Attachment C. 4.5 Water Quality System Basic Water Quality treatment is required per Minimum Requirement # 6 (See Chapter 5 and requires 80% removal of total suspended solids. A 4’x6.5’ Modular Wetland with will be located downstream of detention and has been sized based on the detained 2‐year flow rate of 0.056 as shown below. Dead storage in a 36‐inch diameter pipe will also been provided in Tract D to treat 3,221 square feet of impervious area prior to discharge into the Wetland. It has been sized based on the 24‐hour water quality volume below. EXHIBIT 9 Core Design, Inc. WEST HILL 23 0.0089 ac ft x 43,560 sf = 388 cf Area of a 36‐inch diameter pipe above a 6‐inch sediment storage depth = 6.29 sf 388 cf /6.29 sf = 61.7 feet Therefore, a 62‐foot long pipe has been provided. 4.6 Conveyance System Analysis and Design Conveyance system analysis and design will be addressed during the final design phase of this project. However, storm drain profiles have been provided in Figure 4‐3. 4.7 Managing Stormwater in Wetlands Per Appendix 1‐D of the SWMMWW provides guidelines on the management of stormwater from development to avoid or minimize impacts to existing wetlands. Guide Sheets 1‐3 are addressed below. Guide Sheet 1 The following types of wetland are not suitable as a treatment or flow control facility: 1. The wetland is currently a Category I wetland because of special conditions (forested, bog, estuarine, Natural Heritage, coastal lagoon) Volume I – Minimum Technical Requirements – December 2014 . Response: Both wetlands are a Category III wetlands. 2. The wetland provides a high level of many functions. These are Category I and II wetlands as determined by the Washington State Wetland Rating System of Western Washington. Response: Both wetlands are a Category III wetlands. EXHIBIT 9 Core Design, Inc. WEST HILL 24 3. The wetland provides habitat for threatened or endangered species. Determining whether or not the conserved species will be affected by the proposed project requires a careful analysis in relation to the anticipated habitat changes. Consult with the appropriate agencies with jurisdiction over the specific threatened or endangered species on the site. Response: There are no threatened or endangered species found onsite. However, the wetlands cannot receive flows from a stormwater system unless the criteria in Guide Sheets 3B and 3C are met. Guide sheet 3B cannot be fully met, and guide sheet 3C can be met so therefore the wetland will receive some stormwater runoff, but will not be used as a flow control facility. Guide Sheet 2 A wetland can be both physically or hydrologically altered to meet the requirements of a treatment or flow control facility if all of the following criteria is met: 1. Classified in Category IV or a Category III wetland with a habitat score of 19 points or less Response: Both wetlands are a Category III wetland with a habitat score of less than 19 points. 2. “No net loss” of functions and values of the wetland as a result of the structural or hydrologic modifications done to provide control of runoff and water quality. Response: Using the wetland to control runoff and provide water quality would require disturbances to the wetland. 3. The wetland does not contain a breeding population of any native amphibian species. Response: There were no endangered or threatened amphibian species observed by the wetland consultant. 4. The hydrologic functions of the wetland can be improved as outlined in questions 3,4,5 of Chart 4 and questions 2,3,4 of Chart 5 in the “Guide for Selecting Mitigation Sites Using a Watershed Approach,” or the wetland is part of a priority restoration plan that achieves restoration goals identified in a Shoreline Master Program or other local or regional watershed plan. Response: The hydrologic functions cannot be improved because the site does not contain a culvert that is lower than the surrounding topographic depression. (Question 4, Chart 5) 5. The wetland lies in the natural routing of the runoff, and the discharge follows the natural routing. EXHIBIT 9 Core Design, Inc. WEST HILL 25 Response: Both wetlands lie in the natural routing of the runoff for the west half of the site. All five criteria could not be met so the wetlands cannot be used as a treatment or flow control facility. Guide Sheet 3A This guide sheet discusses ways to protect wetlands from changes to their ecological structure and functions that results from development and recommends actions to minimize harmful changes to wetlands. 1. Consult regulations issued under federal and state laws that govern the discharge of pollutants. Wetlands are classified as "Waters of the United States" and "Waters of the State" in Washington. Response: Acknowledged. 2. Maintain the wetland buffer required by local regulations. Response: A 25’ wetland buffer will be maintained. 3. Retain areas of native vegetation connecting the wetland and its buffer with nearby wetlands and other contiguous areas of native vegetation. Response: The native vegetation in the wetland and buffer will be retained. The buffer will also be enhanced with invasive species removed by hand. 4. Avoid compaction of soil and introduction of exotic plant species during any work in a wetland. Response: The soil will not be compacted in this area nor will exotic plant species be planted. 5. Take measures to avoid general urban impacts (e.g., littering and vegetation destruction). Examples are protecting existing buffer zones; discouraging access, especially by vehicles, by plantings outside the wetland; and encouragement of stewardship by a homeowners' association. Response: There is no vehicular access to the wetland or buffer and signs will be placed around the buffer alert residents that the buffer is the start of a critical area. 6. Fences can be useful to restrict dogs and pedestrian access, but they also interfere with wildlife movements. Their use should be very carefully evaluated on the basis of the relative importance of intrusive impacts versus wildlife presence. EXHIBIT 9 Core Design, Inc. WEST HILL 26 Response: A split rail fence will be placed along the buffer since it is adjacent to the proposed lots. 7. If the wetland inlet will be modified for the stormwater management project, use a diffuse flow method, (e.g. BMPC206 Level Spreader Swale, Volume II, and BMP T5.10B Downspout Dispersion Systems, Volume III) to discharge water into the wetland in order to prevent flow channelization. Response: Discharge to the wetland will be through a flow spreader to prevent channelization. Guide Sheet 3B This guide sheet discusses protecting wetlands from impacts of changes in water flow. Therefore, the wetland fluctuation between the existing (not pre‐developed) and developed conditions was analyzed in WWHM. Tables 4‐4 and 4‐5 and Figures 4‐4 and 4‐2 summarize the existing and developed areas. Table 4‐4 – Wetland Recharge (Existing Conditions) Area (sf) Area (ac) Till‐Forest 33,077 0.76 Till‐Grass 31,690 0.73 TOTAL 64,767 1.49 Table 4‐5 – Wetland Recharge (Developed Conditions) Lot / Tract # Total Area Land Use Area Impervious Till‐Grass sf acre sf acre sf acre 11 1,174 0.03 1,174 0.03 13 7,129 0.16 4,634 0.11 2,495 0.06 14 8,653 0.20 5,624 0.13 3,029 0.07 15 5,259 0.12 3,418 0.08 1,841 0.04 16 5,497 0.13 3,963 0.09 1,534 0.04 17 1,124 0.03 1,124 0.03 18 7,661 0.18 5,370 0.12 2,291 0.05 Tract D 3,341 0.08 3,221 0.07 120 0.00 Total to Wetland 39,918 0.92 26,360 0.61 13,558 0.31 The graph below shows the percent and volume difference between the existing and developed conditions. This project does not meet pass all of the fluctuation tolerances and is further detailed in Appendix C. Since Ecology’s tolerance between the developed and existing volumes to the wetland is so low, any development generally results in not passing all of the monthly and daily fluctuations. Therefore, the areas discharging to the wetland will be adjusted and coordinated with the wetland EXHIBIT 9 Core Design, Inc. WEST HILL 27 biologist to best match the existing hydrology. The vault has been sized with extra capacity to add additional area to the vault as needed to reduce the volume of water to the wetland during final engineering. Guide Sheet 3C Protecting a wetland from pollutants generated by a development should include the following: 1. Use effective erosion control at construction sites in the wetland's drainage catchment. Refer to Volume II this manual and local jurisdiction requirements. Response: An erosion control plan protecting the wetlands from pollutants and sediment will be provided with the construction plans. 2. Institute a program of source control BMPs and minimize the pollutants that will enter storm runoff that drains to the wetland. Response: Only clean water will be discharged to the wetlands. 3. For wetlands the meet the criteria in Guide Sheet 1, provide a water quality control facility consisting of one or more treatment BMPs to treat runoff entering the wetland. Response: A runoff treatment facility will be provided to treat water from Tract D before discharging to the wetland. EXHIBIT 9 EXHIBIT 9 EXHIBIT 9 EXHIBIT 9 EXHIBIT 9 Core Design, Inc. WEST HILL 31 5. DISCUSSION OF MINIMUM REQUIREMENTS EXHIBIT 9 Core Design, Inc. WEST HILL 32 Per Figure 2.4.1 above the proposed project requires that all 10 minimum requirements be addressed. Core Requirement # 1: Preparation of Stormwater Site Plans A Preliminary Stormwater Site Plan has been prepared in accordance with Chapter 4 of the City of Auburn Surface Water Management Manual. The existing and post‐developed conditions of this project site have been outlined and the proposed stormwater facilities and analysis have been described and included in this report. Core Requirement # 2: Construction Stormwater Pollution Prevention The Construction Stormwater Pollution Prevention Plan will be prepared and included in this Report during final design. Core Requirement # 3: Source Control of Pollution Source Control BMPs do not apply to single‐family residential projects. Core Requirement # 4: Preservation of Natural Drainage Systems and Outfalls Natural drainage patterns will be maintained to the maximum extent practicable. The detention vault and modular wetland will discharge water to 59th Avenue S and Lots 13 – 18 and Tract D will discharge to the existing wetland through dispersion trenches to maintain the wetland hydrology to the maximum extent feasible. A hydroperiod analysis has been provided in Section 4 and the level of wetland fluctuations will coordinated with the project’s wetland biologist since the project does not pass on all accounts. Core Requirement # 5: On‐site Stormwater Management Per Figure 2.5.1.A from the COA Supplemental Manual, List #2 will be used to meet the On‐site Stormwater Management requirement. EXHIBIT 9 Core Design, Inc. WEST HILL 33 EXHIBIT 9 Core Design, Inc. WEST HILL 34 Lawn and Landscaped areas: Option 1: Post construction Soil Quality and Depth in accordance with BMP T5.13 in Chapter 5 of Volume V SWMMWW. Response: This site will employ amended soils in lawn and landscape areas in accordance with BMP T5.13 Roofs: Option 1: Full Dispersion in accordance with BMP T5.30 in Chapter 5 of Volume V, or Downspout Full Infiltration Systems in accordance with BMP T5.10A in Section 3.1.1 in Chapter 3 of Volume III SWMMWW. Response: Full dispersion requires a native vegetation flow path of at least 100 feet which cannot be provided on site due to wetlands. Per the geotechnical report completed by Earth Solutions NW, LLC on July 24, 2018, (page 9) “native glacial till should not be considered feasible for infiltration facility design, especially when encountered in a dense, compact state. In general, the glacial till should be considered impervious for practical design purposes.” Pilot infiltration tests resulted in no measurable infiltration rates. Option 2: Bioretention in accordance with Chapter 7 of Volume V 2014 SWMMWW. Response: Per page 9 of the geotechnical report from July 24, 2018, bioretention is infeasible due the medium dense to very dense glacial till that is considered impervious for practical design purposes. Pilot infiltration tests resulted in no measurable infiltration rates. Option 3: Downspout Dispersion Systems in accordance with BMP T5.10B in section 3.1.2 in Chapter 3 of Volume III SWMMWW. Response: It is anticipated that only Lots 13‐14, 16 and 18 will utilize a basic dispersion trench for the roof areas. Lots 1‐7 and 11‐12 do not meet the minimum slope requirement due to the 2:1 grading in the backyard. Lots 8‐10 and 15 cannot provide the minimum vegetated flow path in the front yard and Lot 17 has slopes greater than 20% in the buffer where the vegetated flow path would be. Option 4: Perforated Stub‐out Connections in accordance with BMP T5.10C: Perforated Stub‐out Connections in Section 3.1.3 in Chapter 3 of Volume III SWMMWW. Response: A perforated stub out connection will be provided for each lot. Other Hard Surfaces: Option 1: Full Dispersion in accordance with BMP T5.30 in Chapter 5 Volume V SWMMWW). EXHIBIT 9 Core Design, Inc. WEST HILL 35 Response: Full dispersion requires a native vegetation flow path of at least 100 feet which cannot be provided on site due to wetlands Option 2: Permeable pavement in accordance BMP T5.15 in Chapter 5 of Volume V SWMMWW. Response: Per page 9 of the geotechnical report from July 24, 2018, permeable pavement is infeasible due the medium dense to very dense glacial till that is considered impervious for practical design purposes. Pilot infiltration tests resulted in no measurable infiltration rates. Option 3: Bioretention in accordance with Chapter 7 of Volume V (2014 SWMMWW). Response: Per page 9 of the geotechnical report from July 24, 2018, bioretention is infeasible due the medium dense to very dense glacial till that is considered impervious for practical design purposes. Pilot infiltration tests resulted in no measurable infiltration rates. Option 4: Sheet Flow Dispersion in accordance with BMP T5.12 in Chapter 5 of Volume V SWMMWW. Response: Sheet Flow dispersion will be applied to the walkway and driveway wherever the design parameters can be met. Core Requirement # 6: Runoff Treatment A Modular Wetland downstream of the detention vault is proposed and is in accordance with Volume V of the City of Auburn Surface Water Management Manual. Refer to Chapter 4 of this report for preliminary treatment calculations. Core Requirement # 7: Flow Control A detention vault is in accordance with Volume III of the City of Auburn Surface Water Management Manual, with a deviation from the access road standard. Refer to Chapter 4 of this report for preliminary detention calculations. Core Requirement # 8: Wetlands Protection Stormwater discharges to the wetland are regulated under the City’s Critical Areas Ordinance. The requirements in Section 2.5.8, Volume I of the SWMMWW in addition to the requirements in Chapter 16.10 of the ACC will be followed. Lots 13‐18 and Tract D will discharge to the existing wetland through dispersion trenches to maintain the wetland hydrology to the maximum extent feasible. Guide Sheets 1‐3 have been addressed in Section 4 as well as a hydroperiod analysis. The level of wetland fluctuations will be coordinated with the project’s wetland biologist since the project does not pass on all accounts. Core Requirement # 9: Operation and Maintenance An Operation and Maintenance Manual will be prepared during final design of this project and will be consistent with the provisions in Section 4.1 of Volume I of the COA Supplemental Manual. EXHIBIT 9 Core Design, Inc. WEST HILL 36 Core Requirement # 10: Off‐Site Analysis and Mitigation An off‐site analysis has been prepared and included in Chapter 3 of this report. A quantitative analysis downstream of the site has been provided. EXHIBIT 9 APPENDIX A OPERATION AND MAINTENANCE (O & M) MANUAL (PROVIDED DURING FINAL ENGINEERING) EXHIBIT 9 ATTACHMENT B CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN (PROVIDED DURING FINAL ENGINEERING) EXHIBIT 9 ATTACHMENT C HYDRAULIC/HYDROLOGIC ANALYSIS AND MODELING RESULTS NOT INCLUDED IN HEARING EXAMINER PACKET EXHIBIT 9 EXHIBIT 9 ATTACHMENT D OTHER SPECIAL REPORTS (UNDER SEPARATE COVER) EXHIBIT 9 ATTACHMENT E DECLARATION OF COVENANT FOR PRIVATELY MAINTAINED FACILITIES (PROVIDED FOLLOWING COMPLETION AND ACCEPTANCE OF CONSTRUCTION) EXHIBIT 9 EXHIBIT 10 EXHIBIT 10 From: Shannon Howard <showard@auburnwa.gov> Sent: Thursday, July 18, 2019 4:53 PM To: Sheri H. Murata Cc: 'Evan Mann'; Development; Thaniel Gouk Subject: DEV19-0010 West Hill Preliminary Plat Detention Vault Good Afternoon Sheri- The City Engineer has reviewed the West Hill Preliminary Plat Detention Vault Deviation Request (DEV19-0010) submitted for the West Hill Preliminary Plat project. The results of that review are provided below. Deviation Request (DEV19-0010) received June 29, 2019, is associated with the West Hill Preliminary Plat project (PLT18-0004), a pending submittal. Applicant requests approval of the construction of a detention vault to meet the flow control requirements triggered by the project. The detention vault will be located within a tract per City requirements. Following completion of the project, the City of Auburn will assume ownership and maintenance responsibilities for the detention vault. Chapter 3.2 of Volume III of the City of Auburn Surface Water Management Manual (SWMM) requires that detention facilities that will be owned and/or operated by the City or be located within the right-of- way shall be detention ponds. The City Engineer may grant a deviation from the SWMM if the applicant demonstrates that the proposed deviation will meet or exceed the corresponding City standard for the criteria listed in Section 1.04.1 of the Engineering Design Standards. In this case, the City Engineer has determined that the proposal meets or exceeds the corresponding City standards, except as follows: 1. The proposal does not meet criteria 1.04.1.C, operational concerns associated with the design element. The associated appurtenances and structures that are required components of the storm system are not shown to meet City engineering and maintenance requirements at this time. Further design is required to provide associated accessible structures within the storm tract. Based on the above, the City will recommend to the Hearing Examiner that the Deviation Request be approved with the following conditions: - The associated appurtenances and structures that are required to meet all applicable storm requirements for flow control and treatment shall be modified during final engineering design as needed to meet City requirements for maintenance and access. This includes modifications as needed to location, configuration, and depth of all structures and appurtenances associated with the detention vault. Per Chapter 3, Appendix C of the Engineering Design Standards, approved Deviation Requests must include the appropriate plan sheet callouts and descriptions. Please refer to that section when including the required plan sheet elements for both approved Deviation Requests. Please let me know if you have any questions. EXHIBIT 11 Thank you, Shannon Howard, PE CFM Development Review Engineer Department of Community Development City of Auburn | www.auburnwa.gov Phone: (253) 804-5073 | showard@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Map) Customer Service Survey | Application Forms | Zoning Maps This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. EXHIBIT 11 • 12100 NE 195th Street, Suite 300 • Bothell, Washington 98011 • Ph 425.885.7877 • www.coredesigninc.com J:\2018\18069\Documents\Engineering Reports\Deviation Request\Deviation Request.docx TECHNICAL MEMORANDUM To: Shannon Howard, P.E. CFM Development Review Engineer From: Sheri Murata, P.E. Core Design, Inc. Date: February 22, 2019 Re: Pond Deviation Request Pursuant to the City of Auburn instructions for requesting and approving deviation requests, we submit the following for consideration. Description of Deviation Requested: We are requesting to construct a detention pond with four walls and an access road with steeper slope than the maximum slope typically allowed by the City. Code section from which Deviation is requested: The applicant is requesting a deviation from the following under Section 3.2.1 of the City’s Supplemental Manual to the Ecology Stormwater Management Manual for Western Washington, Volume III: · A 3’ wide bench shall be provided at the 10-year storm storage elevation · For pond where retaining walls are required, they shall be limited to a maximum of three sides · At least 25% of the pond perimeter shall be a vegetated soil slope not steeper than 3H:1V A deviation is also requesting a deviation from the following taken from Appendix K of City’s Supplemental Manual to the Ecology Stormwater Management Manual for Western Washington, Volume I: · The beginning and end of the access road shall have a slope less than 7% for a minimum distance of 50 feet · The inside turning radius shall be a minimum of 45 feet Per the City of Auburn Deviation Request Application detailed supporting justification for the design element for each of the following criteria outlined in Section 1.05 of the City of Auburn Design Standards. 1. Functional Intent The proposed detention pond will still meet the flow control criteria per the Department of Ecology Stormwater Management Manual for Western Washington (DOE Manual) which matches developed discharge duration to pre-developed durations for the range of pre-developed discharge rates from 50% of the 2-year peak up to the full 50-year peak flow. EXHIBIT 11 Shannon Howard, P.E. CFM February 22, 2018 Pond Deviation Request Page 2 J:\2018\18069\Documents\Engineering Reports\Deviation Request\Deviation Request.docx 2. Safety Factors A 6’ high fence will be placed on top of the wall for the entire perimeter of the pond. Bollards will also be placed on the pond access road to ensure that only maintenance vehicles access the pond. 3. Operational Concerns The pond will operate as intended because the pond has been modeled with parameters that match the proposed design. 4. Maintenance Concerns The access road to the pond does not exceed the City’s maximum slope of 12% for an access road and maintenance staff will be able to remove the bollards and drive to the bottom of the pond to remove sediment. Maintenance will be reduced since the only vegetated slope to maintain is on the sides of the access road. 5. Liability Concerns A 6’ high fence will be placed on top of the wall for the entire perimeter of the pond. Bollards will also be placed on the pond access road to ensure that only maintenance vehicles access the pond. 6. Capabilities and/or Efficiencies The fourth wall, increased access road grade reduced inside turning radius will allow the pond to meet the flow control standard and be closer to meeting the minimum density requirements. At 18 lots this site doesn’t meet the minimum density requirement and removing a lot will decrease the density even further. 7. Design Life, historical performance and durability The design life of the wall is estimated to be about 50 years. 8. Aesthetic and Visual Impacts A fence and landscaping will be placed around the fence to screen the pond from the surrounding homes as much as possible. 9. The cost effectiveness and availability of any replacement components or materials It is not anticipated that the concrete retaining wall would need to be replaced. 10. Consistency with spirit and purpose of the corresponding City design standard The pond with four walls is consistent with maintaining the City’s preference for ponds (versus detention vaults), meeting the flow control requirements and maximizing the density of the plat. 11. Demonstration that the environment will not be adversely affected The requested deviation does not adversely affect the environment. 12. Supported by published industry standards The access road slope and internal radius matches the pond design standards in the DOE Manual. The 3’ wide bench is also not one of the design standards in the DOE Manual. Based on the above discussion, variations to the pond design standards, as listed above, are reasonable and approval is requested. Please contact me with any comments and questions at (425) 885-7877 or shm@coredesigninc.com. EXHIBIT 11 From: Shannon Howard <showard@auburnwa.gov> Sent: Thursday, May 30, 2019 9:50 AM To: 'Sheri H. Murata' Cc: Development; Thaniel Gouk; 'evan@soundbuilthomes.com' Subject: DEV19-0019 West Hill Plat Access Tract Good Morning Sheri- The City Engineer has reviewed the Deviation Request (DEV19-0019) submitted for the West Hill Preliminary Plat project (PLT18-0004). The results of that review are provided below. Deviation Request (DEV19-0019) received May 13, 2019, is associated with the West Hill Preliminary Plat submittal (PLT18-0004). Applicant requests approval of the construction of a private access tract with a slope of 8.66%. The access tract serves four proposed lots, a public detention pond, and functions as emergency access for the plat located on a dead-end cul-de-sac. DEV19-0019 is associated with DEV19- 0010, a request by the applicant to construct a pond that deviates from City design standards for public stormwater detention ponds. Chapter 10.01.5.5 of the City of Auburn Engineering Design Standards (EDS) requires that roads in access tracts meet the geometric design standards for local residential streets. Table 10-1 in Chapter 10 of the EDS requires that the maximum vertical grade of local residential streets is 8%. The City Engineer may grant a deviation from the EDS if the applicant demonstrates that the proposed deviation will meet or exceed the corresponding City standard for the criteria listed in Section 1.04.1 of the EDS. In this case, the City Engineer has determined that the proposal meets or exceeds the corresponding City standards except as follows: 1. The proposal does not meet criteria 1.04.1.B, safety factors associated with the design element. The proposed access tract grade creates potential safety concerns for all vehicles because the minimum landing approach grade of less than 5% for the minimum landing approach length of 20 feet is not provided. This creates safety issues for vehicles entering and exiting the tract. 2. The proposal does not meet criteria 1.04.1.J, consistency with the spirit and purpose of the corresponding City design standard. The spirit and purpose of the design standard is to create safe road networks where the risk of collisions and other safety incidences are less likely to occur. The increased slope of the access tract prevents meeting other components of the same design standard that cannot be resolved through design given the site constraints. Based on the above, the access tract cannot be approved as it is currently designed, therefore approval of the Deviation Request cannot be recommended to the Hearing Examiner for the preliminary plat. The City welcomes further discussion regarding the deviation requests and the access tract configuration so that a solution may be found the suits the project needs and can be recommended by staff for approval by the Hearing Examiner. Please let me know if you have any questions. Thank you, EXHIBIT 12 Shannon Shannon Howard, PE CFM Development Review Engineer Department of Community Development City of Auburn | www.auburnwa.gov Phone: (253) 804-5073 | showard@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Map) Customer Service Survey | Application Forms | Zoning Maps This message is private and privileged. If you are not the person meant to receive this message, please let the sender know, then delete it. Please do not copy or send it to anyone else. EXHIBIT 12 • 12100 NE 195th Street, Suite 300 • Bothell, Washington 98011 • Ph 425.885.7877 • www.coredesigninc.com J:\2018\18069\Documents\Engineering Reports\Deviation Request\Tract A\Deviation Request.docx TECHNICAL MEMORANDUM To: Shannon Howard, P.E. CFM Development Review Engineer From: Sheri Murata, P.E. Core Design, Inc. Date: April 24, 2019 Re: Road Deviation Request Pursuant to the City of Auburn instructions for requesting and approving deviation requests, we submit the following for consideration. Description of Deviation Requested: We are requesting to construct a private road (designed to Local Residential Standards) with a slope of 8.66%. Code section from which Deviation is requested: The applicant is requesting a deviation from Table 10-1 Summary Matrix of Minimum Street Design Requirements of the Engineering Design Standards: · Maximum vertical grade of 8% for a Local Residential Street Per the City of Auburn Deviation Request Application detailed supporting justification for the design element for each of the following criteria outlined in Section 1.05 of the City of Auburn Design Standards. 1. Functional Intent The functional intent of the road for four lots, pond access and emergency access will not be affected. 2. Safety Factors There are no safety issues with a road slope of 8.66%, since the typical maximum slope for fire access is 15%. 3. Operational Concerns The road will operate whether the road is 8.66% or under 8%. 4. Maintenance Concerns The Tract A road is a private road so there would be no maintenance concerns for the City. 5. Liability Concerns The Tract A road is a private road so there would be no liability concerns for the City. EXHIBIT 12 Shannon Howard, P.E. CFM February 22, 2018 Road Deviation Request Page 2 J:\2018\18069\Documents\Engineering Reports\Deviation Request\Tract A\Deviation Request.docx 6. Capabilities and/or Efficiencies The increase in the Tract A road slope allows the pond access to be designed with a 30’ radius, slope no greater than 12% and a vertical curve at where the pond access intersects the Tract A road. 7. Design Life, historical performance and durability An increase in the road slope does not affect the design life of the road. 8. Aesthetic and Visual Impacts There are no aesthetic and visual impacts as a result of a road greater than 8% in slope. 9. The cost effectiveness and availability of any replacement components or materials There are no impacts to cost or the availability of replacement components as a result of a road greater than 8% in slope. 10. Consistency with spirit and purpose of the corresponding City design standard A road slope greater than 8% allows the project to meet the City’s design standards for the pond access road. 11. Demonstration that the environment will not be adversely affected The requested deviation does not adversely affect the environment. 12. Supported by published industry standards Industry standards typically have a maximum slope of 15% and the proposed road has a slope of 8.66%. Based on the above discussion, the variation to the road design standards, as listed above, are reasonable and approval is requested. Please contact me with any comments and questions at (425) 885-7877 or shm@coredesigninc.com. EXHIBIT 12 From: Shannon Howard <showard@auburnwa.gov> Sent: Monday, September 30, 2019 10:41 AM To: 'Sheri H. Murata' Cc: 'Evan Mann'; Development; Thaniel Gouk Subject: DEV19-0032 West Hill Plat Design Speeds Good Morning Sheri- The City Engineer has reviewed the Deviation Request (DEV19-0032) submitted for the West Hill Preliminary Plat project (PLT18-0004). The results of that review are provided below. Deviation Request (DEV19-0032) dated September 27th, 2019, is associated with the West Hill Preliminary Plat project (PLT18-0004). Applicant requests approval of a reduction to Local Residential design speeds from 30 MPH to 25 MPH for a crest curve and 15 MPH for a sag curve. The reduced design speeds are applicable to a dead-end cul-de-sac on a Local Residential street, 58th Ave S, as shown in the review documents for the project. Table 10-1, Chapter 10 of the Engineering Design Standards (“EDS”), dated January 3, 2019, indicates that the geometric design of Local Residential streets shall use a design speed of 30 MPH. The City Engineer may grant a deviation from the EDS if the applicant demonstrates that the proposed deviation will meet or exceed the corresponding City standard for the criteria listed in Section 1.04.1 of the EDS. In this case, the City Engineer has determined that the proposal meets or exceeds the corresponding City standards found in that section. Based on the above, the Deviation Request is approvable. The City Engineer will recommend approval of DEV19-0032 to the Hearing Examiner for the plat. Appeals of the City Engineer’s decision shall follow the procedure found in City of Auburn Engineering Design Standards Section 1.05. The applicant shall have 15 working days from the date of receipt of the decision in which to submit a written notice to the Public Works Director contesting the decision of the City Engineer. The Public Works Director shall then have 15 working days to notify the applicant of a decision to uphold or modify the City Engineer’s decision. For appeals of engineering Deviation Requests, the Public Works Director’s determination shall be final. Please let me know if you have any questions. Thank you, Shannon Howard, PE CFM Development Review Engineer Department of Community Development City of Auburn | www.auburnwa.gov Phone: (253) 804-5073 | showard@auburnwa.gov Mailing Address: 25 W Main Street, Auburn, WA 98001 EXHIBIT 13 Permit Center Address: 1 E Main Street, Auburn, WA 98002 (Map) Customer Service Survey | Application Forms | Zoning Maps EXHIBIT 13 • 12100 NE 195th Street, Suite 300 • Bothell, Washington 98011 • Ph 425.885.7877 • www.coredesigninc.com J:\2018\18069\Documents\Engineering Reports\Deviation Request\Design Speed\Deviation Request.docx TECHNICAL MEMORANDUM To: Shannon Howard, P.E. CFM Development Review Engineer From: Sheri Murata, P.E. Core Design, Inc. Date: September 27, 2019 Re: Design Speed Deviation Request Pursuant to the City of Auburn instructions for requesting and approving deviation requests, we submit the following for consideration. Description of Deviation Requested: We are requesting to reduce the design speed from 30 mph (25 mph posted) to 25 mph for the crest curve and from 30 mph to 15 mph for the sag curve on 58th Ave S. Code section from which Deviation is requested: The applicant is requesting a deviation from Table 10-1 of the City’s Engineering Design Standards for the design speed of 30 mph for a local residential street. Per the City of Auburn Deviation Request Application detailed supporting justification for the design element for each of the following criteria outlined in Section 1.05 of the City of Auburn Design Standards. 1. Functional Intent The proposed extension of 58th Avenue S will extend about 200 feet from the flowline of S 294th Street and end in a cul-de-sac so vehicles will not be traveling at a speed of 25 mph. Reducing the design speed does not limit the ability of vehicles to travel on 59th Avenue S. It provides a more realistic representation of the actual speed that vehicles will be traveling at due to the short road length and road end. 2. Safety Factors To ensure that vehicles will travel below the posted speed limit of 25 mph a raised island will be constructed as a traffic calming in the middle of the cul-de-sac. The curb around the raised island will be mountable such that emergency vehicles and garbage trucks can drive over them to maneuver through the cul-de-sac. 3. Operational Concerns 58th Avenue S and Tract A will operate as intended with only local access to the residents in the plat. EXHIBIT 13 Shannon Howard, P.E. CFM September 27, 2019 Design Speed Deviation Request Page 2 J:\2018\18069\Documents\Engineering Reports\Deviation Request\Design Speed\Deviation Request.docx 4. Maintenance Concerns The requested deviation does not affect any road maintenance of 58th Avenue S. 5. Liability Concerns Traffic will be traveling west on S 294th Street and slowing down to make a right turn onto 58th Avenue S. The short road length and raised island will result in vehicles traveling well below 20 mph at the south end of 58th Avenue S and at or below 10 mph in the cul-de-sac so there should be no additional liability concerns. 6. Capabilities and/or Efficiencies The reduced design speed allows for shorter vertical curve lengths on 58th Avenue S. The short curve lengths allow the proposed roads to meet other design standards such as a maximum road slope of 8% and minimum 20-foot landing approach length at a 5% grade as shown in Table 10-1 under local residential streets. 7. Design Life, historical performance and durability A reduced design speed will not affect the design life, historical performance or durability of the streets. 8. Aesthetic and Visual Impacts There will be no aesthetic or visual impacts as a result of the requested deviation. 9. The cost effectiveness and availability of any replacement components or materials The reduced design speed will not affect the cost effectiveness or availability of any replacement components or materials. 10. Consistency with spirit and purpose of the corresponding City design standard The reduced design speed will not reduce the function or safety of 58th Avenue S. The raised island will be consistent with the City’s standard of providing an alternate section for local residential streets for traffic calming. (See footnote 2 on Table 10-1) 11. Demonstration that the environment will not be adversely affected The requested deviation does not adversely affect the environment. 12. Supported by published industry standards Jurisdictions like Snohomish County allow for a reduced design speed on a cul-de-sac road with tangents no longer than 250 feet. Based on the above discussion, a reduction in the design speed standard, as listed above, are reasonable and approval is requested. Please contact me with any comments and questions at (425) 885-7877 or shm@coredesigninc.com. EXHIBIT 13