Loading...
HomeMy WebLinkAboutAppendix B Air Quality APPENDIX B AIR QUALITY ASSESSMENT MFG CONSULTANTS MARCH 2, 2004 City of Auburn Kersey III Residential Development Project Air Quality Analysis Prepared For: Apex Engineering, Inc. th 2601 South 35 Suite 200 Tacoma, WA 98409 MFG Project 9826 March 2, 2004 MFG, Inc. 19203 36th Avenue W, Suite 101 Lynnwood, WA 98036-5772 (425) 921-4000 FAX (425) 921-4040 Arcata, CA * Austin, TX * Boulder, CO * Coeur d'Alene, ID * Fort Collins, CO Fresno, CA * Grand Junction, CO * Houston, TX * Irvine, CA * Leadville, CO * Lynnwood, WA Omaha, NE * Orlando, FL * Pittsburgh, PA * Port Lavaca, TX * San Francisco, CA TABLE OF CONTENTS SUMMARY....................................................................................................................................1 STUDIESAND METHODOLOGY...............................................................................................3 PD...................................................................................................................3 ROJECTESCRIPTION MA....................................................................................................................3 ETHOD OF NALYSIS CALQ3QHC–EI...................................................................................6 VALUATEDNTERSECTIONS CAL3QHCDMPA..............................................6 ISPERSIONODELINGARAMETERS AND PPLICATION AFFECTED ENVIRONMENT......................................................................................................9 EAQ..................................................................................................................9 XISTINGIRUALITY Carbon Monoxide...................................................................................................................10 Ozone.....................................................................................................................................10 Inhalable Particulate Matter (PM).......................................................................................11 10 Fine Particulate Matter (PM)..............................................................................................12 2.5 HE.........................................................................................................................12 EALTHFFECTS Carbon Monoxide...................................................................................................................12 Ozone.....................................................................................................................................12 PM and PM......................................................................................................................12 102.5 IMPACTS.....................................................................................................................................13 IDC................................................................................................13 MPACTSURINGONSTRUCTION No Action Alternative..............................................................................................................13 Action Alternative...................................................................................................................13 IDO......................................................................................................13 MPACTSURINGPERATION No Action Alternative..............................................................................................................14 Action Alternatives..................................................................................................................15 ICI..........................................................................................15 NDIRECT AND UMULATIVEMPACTS CONFORMITY WITH STATE IMPLEMENTATION PLAN..................................................16 MITIGATION..............................................................................................................................17 MDC..........................................................................................17 ITIGATIONURINGONSTRUCTION MDO.................................................................................................18 ITIGATIONURINGPERATION SUAI............................................................................18 IGNIFICANTNAVOIDABLEDVERSEMPACTS REFERENCES.............................................................................................................................19 LIST OF TABLES TABLE 1. Calculated Maximum PM Peak-Period CO Concentrations (ppm)……………………..13 Kersey III Residential Development ProjectiMarch 2, 2004 Air Quality Analysis LIST OF FIGURES FIGURE 1. Vicinity Map…………………………………………………………………………... 4 FIGURE 2. Typical Link and Receptor Geometry………………………………………………….7 Kersey III Residential Development ProjectiiMarch 2, 2004 Air Quality Analysis SUMMARY TheKersey III Residential Development Project would develop 170 acres of currently-forested land in Auburn, WA. Alternative 481– the Proposed Action-Low Density Preliminary Plat alternative – would construct 481 single-family homes. With Alternative 700 – the High Density Planned Unit Development alternative– in place, 700 homes would be constructed. Both alternatives would involve construction in three divisions and six phases. In addition, each alternative would construct an arterial between Evergreen Way SE and Kersey Way. Additional roadway work would include the dedication and construction of about 4 miles of new public rights-of-way to serve development and provide internal circulation within the development. This project lies just north of the Pierce County border in King County, in a maintenance area for ozone (O) and carbon monoxide (CO). Project-level air quality modeling was conducted as part of the 3 environmental review, and the Puget Sound Regional Council’s (PSRC) Regional Transportation Improvement Program was reviewed to assess compliance with Federal and State air quality laws. This report summarizes the air quality impact analysis completed as part of the environmental review. The analysis used Microscale hot-spot air quality modeling to compare the traffic-related air quality impacts of the Action and No Action Alternatives in the project’s opening (2005) and design (2020) years. Modeling results were compared with federal and state ambient air quality standards. Because the project is located within a carbon monoxide (CO) maintenance area, and because CO is the pollutant of concern when analyzing air quality impacts from vehicular traffic, CO concentrations were the focus of this analysis. The two federally recommended models (CAL3QHC and MOBILE5b) were used to determine 1-hour CO levels near intersections directly affected by the project. Eight-hour concentrations were calculated using a persistence factor recommended by the EPA. Predicted 1-hour and 8-hour CO levels near the affected intersections were compared to the ambient air quality standards (35 ppm for 1-hour and 9 ppm for 8-hour) to determine conformity with current air quality rules. Existing year (2002) traffic conditions were modeled at the intersections of Auburn Way South with “M” th Street SE, Ellingson Road with East Valley Highway and Stewart Road SE with 136 Avenue East. The intersections of Ellingson Road with East Valley Highway (also referred to as “A” Street and Auburn Avenue) and “C” Street were modeled together due to their proximity to each other (project-significant intersections within 1000 feet of each other are modeled together). The model-predicted CO levels with worst-case existing conditions revealed CO levels that would exceed the 9-ppm 8-hour standard at one of the four intersections examined (namely, Ellingson Road and “C” Street). The remaining three intersections would not appear to currently threaten air quality at nearby locations under existing conditions. Modeling results for the Alternatives A and B, as well as the No Action alternative, revealed model- predicted CO levels in the opening and design years that were both less than existing levels and less than the concentrations allowed by the 1-hour and the 8-hour ambient standards. Because project-traffic- related emissions are not predicted to cause ambient air quality concentrations that exceed the standards, the proposed project is not likely to adversely affect air quality, and also would conform to current air quality rules. Kersey III Residential Development Project1March 2, 2004 Air Quality Analysis Since this project is regionally significant and is located in a maintenance area for CO, it must demonstrate project level and regional conformity of the EPA Conformity Rule, and with WAC Chapter 173-420. The roadway and arterial proposed to supplement the Kersey III development have not been included in PSRC’s conforming Metropolitan Transportation Plan (MTP) and have not been shown to meet the Central Puget Sound Regional Transportation Improvement Program (RTIP) conformity requirements for a regionally significant project. However, it is anticipated that these aspects of the project will be included as amendments both the MTP and the RTIP. Mitigation Operational mitigation would not be required for this project. Construction activities would result in temporary emissions of pollutants, including dust and odors. Best management practices for dust abatement would be used during construction to reduce dust emissions. Kersey III Residential Development Project2March 2, 2004 Air Quality Analysis STUDIES AND METHODOLOGY Project Description The Kersey III Residential Development Project is a housing development proposed by the City of Auburn. Alternative 481, which represents the proposed Action alternative, would involve the development of a low-density preliminary plat of 481 single-family homes on a 167-acre parcel. Alternative 700, the high-density alternative, would involve the development of a high-density preliminary plat of 700 single-family homes on a 167-acre parcel. Alternative C, which is the No Action alternative, would allow for the subdivision of the site into approximately 403 lots with each of the parcel developed individually. Alternatives A and B would also include the construction of an arterial between Kersey Way and Evergreen Way SE and additional roadway for internal circulation throughout the development A site vicinity map is located in Figure 1. Method of Analysis Traffic generated by the project would affect carbon monoxide (CO) emissions in the Puget Sound CO maintenance area. Consequently, any major changes to the road network or other elements of the transportation system due to the project are subject to review under state and federal air quality conformity rules. These rules are intended to ensure that projects and actions affecting air quality will conform to existing plans and time tables for attaining and then maintaining federal health-based air quality standards. The proposed project is subject to a full air quality conformity review, and the analysis reported here compromises a project-level "hot spot" analysis. Two standard computerized tools were used to evaluate potential air quality impacts from the proposed project in both its opening (2005) and design (2020) years. Peak-hour pollutant emission rates due to traffic in the project area were computed using the Mobile Source Emissions Model. Worst-case peak-hour CO concentrations were then estimated using the CALQHC dispersion model. Both tools are described further below. The U.S. EPA requires a MOBILE series emission factor model be employed in analyses investigating the air quality implications of surface transportation sources. Mobile6 was released in 2002 and is the latest in a series of tools for use in such analyses. Currently, the Puget Sound Regional Council (PSRC) is examining ways to provide Mobile6 information for general use and has approved its use for some projects in the Puget Sound area. This model was not, however, ready for general use at the time this analysis began. In accordance with the agreement between the EPA and the PSRC, the PSRC was contacted regarding vehicle emission factors for the years of analysis being considered for the Kersey III Residential Development Project (PSRC 2003). The PSRC ran the Mobile5b model, made appropriate adjustments, and provided the CO emission factors for use in the modeling analysis.The Mobile5b input parameters were consistent with those used in the development of the Washington State Implementation Plan and Maintenance Plan for CO in the Puget Sound region, in accord with Washington Department of Ecology (Ecology) and Puget Sound Clean Air Agency (PSCAA) recommendations. Kersey III Residential Development Project3March 2, 2004 Air Quality Analysis The Tier II Adjusted CO Mobile5b emission factors and worst-case meteorological conditions were input to the CAL3QHC dispersion model (EPA 1992a) to calculate ambient CO concentrations near the four Kersey III Residential Development Project4March 2, 2004 Air Quality Analysis N Not to Scale Project Site Figure 1. Vicinity Map Kersey III Residential Development Project5March 2, 2004 Air Quality Analysis signalized intersections selected for "hot-spot" modeling. The intersections that were most impacted by the project-related traffic were selected for dispersion modeling based on EPA guidance discussed below. CALQ3QHC– Evaluated Intersections Consistent with EPA guidance, project-affected, signalized intersections that would be affected by proposed action alternatives were screened for possible dispersion modeling by reviewing the traffic level of service (LOS) analyses, total traffic volume, and project-related trips in the future year. Intersections are selected for analysis by ranking affected intersections with the worst (most congested) LOS and those with the highest daily or peak-hour volumes, and selecting up to three from each category. The EPA suggests modeling intersections with an LOS that would deteriorate to "D" or worse due to a proposed 1 project. EPA guidance, therefore, focuses on completing modeling analyses at as few as three to as many as six signalized intersections, if warranted. Based on EPA guidance and available traffic data, three intersections were selected for detailed dispersion modeling for this project. These intersections are: Auburn Way South with “M” Street, Ellingson th Road with East Valley Highway and Steward Street with 136 Avenue E. The intersection of Ellingson Road with “C” Street was also modeled, due to its proximity to the Ellingson and East Valley Highway intersection. CAL3QHC Dispersion Modeling Parameters and Application The CAL3QHC, Version 2, dispersion model was used to calculate peak-hour CO concentrations near the most project-affected intersections. CAL3QHC is a dispersion model designed to calculate pollutant concentrations caused by transportation sources (EPA 1992a). It considers "free-flow" and "queue" emissions (based on Mobile5b emission factors) together with intersection geometry, wind direction, and other meteorological factors. Although the project site is located in a steeply-sloped area, the most- affected intersections were located and modeled at grade. The following assumptions and parameters were used in the CAL3QHC modeling and are consistent with the Washington State CO SIP, CO Maintenance Plan, and EPA guidance for dispersion modeling: Critical meteorological parameters were a 3280.8 feet mixing height, low wind speed 3.28 feet/second), and a stable atmosphere (Class E) (EPA 1992b). The modeling evaluated 36 wind directions (in 10° increments) to ensure worst-case conditions were considered for each receptor location (EPA 1992b). A "background" 1-hour CO monoxide concentration of 3 ppm was assumed to represent other suburban sources in the project area (EPA 1992b). ______________________________________________________________________________ ______ 1 LOS is a measure of the weighted average vehicle delay during the peak traffic period at a signalized intersection. LOS "A" is the least congested, with an average delay of less than 10seconds per vehicle. LOS "F" represents a weighted average delay of more than 80 seconds per vehicle. Kersey III Residential Development Project6March 2, 2004 Air Quality Analysis The modeling configuration considered road links extending 1,000 feet from each intersection. Using the procedures required for the CAL3QHC dispersion model, both free-flow and queue links were configured approaching and departing the intersections evaluated. Near-road receptors were placed 10 feet, 82.5 feet, 165 feet, and 330 feet from cross streets, 10 feet from the nearest traffic lane, and 5.7 feet above the ground to correspond to a typical sidewalk location at breathing height (see Figure 2). Modeling used up to 32 near-road receptors near the intersections (EPA 1992b). The p.m. peak-hour traffic conditions provided by the transportation consultant would lead to the highest possible 1-hour and 8-hour CO concentrations. Assumed travel speed ranged from 25 to 45 m.p.h. Traffic signals were modeled by the traffic engineer as actuated, however, the CAL3QHC model is not designed to assume that intersections are interconnected. An average optimal cycle time of 104, 130 and 154 were used for the three intersections for the 2005 year of opening as well as the 2020 design year. The project-affected intersections were assumed to be at grade. Modeled 1-hour concentrations were converted to represent 8-hour concentrations using a "persistence factor" (i.e., the ratio of 8-hour to 1-hour CO concentrations) to represent variability in both traffic volumes and meteorological conditions. Since actual monitoring data were not available, an EPA default persistence factor of 0.7 was used. Kersey III Residential Development Project7March 2, 2004 Air Quality Analysis Figure 2. Typical Link and Receptor Geometry. Kersey III Residential Development Project8March 2, 2004 Air Quality Analysis AFFECTED ENVIRONMENT Typical air pollution sources in the project area include vehicular traffic, commercial enterprises, and residential wood-burning devices. Residential wood burning produces a variety of air contaminants, including large quantities of fine particulate matter (PM and PM). With vehicular traffic, the air 102.5 pollutant of major concern is carbon monoxide (CO). Of the various vehicular emissions for which there are ambient air quality standards, CO is the pollutant emitted in the largest quantities. The terrain where the project would be constructed is sharply sloped, however, the intersections at which the largest traffic increases will occur are located in relatively flat areas with no immediate topographical changes. Other pollutants generated by traffic include the ozone precursors: hydrocarbons and nitrogen oxides. Fine particulate matter (PM and PM) is also emitted in vehicle exhaust and generated by tire action on 102.5 pavement (or unpaved areas). The PM and PM levels generated by individual vehicles are small 102.5 compared with other sources (e.g., a wood-burning stove). Sulfur oxides and nitrogen dioxide are also both emitted by motor vehicles, but concentrations of these pollutants are usually not high, except near large industrial facilities. Pollutant emissions from residential wood burning (RWB) devices including fireplace and wood stoves could represent a large potential emissions source from the proposed development. Federal (EPA), state (Ecology) and local air pollution control authorities have long recognized the potential threat to air quality from this emission source. RWB represents a potentially significant source of fine particulate matter (PM), carbon monoxide (CO), and various air toxics. PM concentrations near a single, poorly 2.52.5 operating RWB stove can exceed the pollutant levels allowed by state and federal health standards. Near whole neighborhoods of fireplaces and stoves, air quality can be significantly deteriorated in a very short time during periods of low winds and poor dispersion. PM also can reduce long-range visibility and 2.5 contribute to regional haze. As a result of what are now clearly delineated potential impacts, federal, state, and local air pollution control authorities carefully scrutinize proposed installations of large numbers of RWB units, and often require extensive analyses to estimate impacts. The developer has agreed to propose gas-fired heating units. If this proposal is implemented, there would be no impacts expected in accordance with these appliances. Existing Air Quality Air quality is generally assessed by determining whether concentrations of air pollutants are higher or lower than ambient air quality standards set to protect human health and welfare. Three agencies have jurisdiction over the ambient air quality in the project area: the EPA, Ecology, and PSCAA. These agencies establish regulations that govern both pollutant concentrations in the outdoor air and contaminant emissions from air pollution sources. Although their regulations are similar in stringency, each agency has established its own standards. Unless the state or local jurisdiction has adopted more stringent standards, the EPA standards apply. To measure existing air quality, Ecology and PSCAA maintain a network of monitoring stations throughout the Puget Sound region. Generally these stations are placed where air quality problems may occur, and so they are usually in or near urban areas or close to specific large air pollution sources. Other stations in remote areas indicate regional air pollution levels. Based on monitoring information collected over a period of years, the state (Ecology) and federal (EPA) agencies designate regions as being "attainment" or Kersey III Residential Development Project9March 2, 2004 Air Quality Analysis "nonattainment" areas for particular air pollutants. Attainment status is therefore a measure of whether air quality in an area complies with the National Ambient Air Quality Standard (NAAQS). Carbon Monoxide Carbon monoxide, the product of incomplete combustion, is generated by transportation sources and other fuel-burning activities like residential space heating, especially when solid fuels like coal or wood are used. Carbon monoxide is usually the pollutant of greatest concern related to transportation sources because it is the pollutant emitted in the greatest quantity for which there are short-term health standards. Short-term standards (as opposed to annual-average standards) are often the controlling or most restrictive NAAQSs (Table 1). There are two air quality standards for CO: a 1-hour average standard of 35 ppm and an 8-hour average standard of 9 ppm. These levels may be exceeded once per year without violating the standard. Calculated 8-hour CO concentrations of 9.1 pm or higher would violate the NAAQS. CO is a pollutant whose impact is usually localized. The highest ambient CO concentrations usually occur near congested roadways and intersections during periods of cold temperatures (autumn and winter months), light winds, and stable atmospheric conditions. Such weather conditions reduce the mechanisms that disperse pollutants emitted into the air. The project study area is located in the CO nonattainment area established in 1991 that encompassed a large portion of the Everett-Seattle-Tacoma urban area. Designation of the area as a CO nonattainment area required PSCAA and Ecology to develop strategies and plans to achieve compliance with the ambient standards. These plans led to attainment of the standards before 1997. In that year, the EPA designated the area as an attainment area, and approved a maintenance plan developed to ensure the continued attainment of the CO standards. The former CO nonattainment area is now considered a CO "maintenance" area. The CO maintenance plan relies on continuation of the existing vehicle Inspection and Maintenance program. The CO monitoring station closest to the project area is located in Tacoma at 1101 Pacific Avenue. This station and others in the Puget Sound region have not measured a violation of the 1-hour or 8-hour CO standard in recent years (EPA 2004). Because CO impacts occur close to the source, it is not possible to extrapolate CO concentrations from regional data or distant monitors to the project area. But given trends throughout the region, it is likely that CO levels in and around the project area are well below health-based standards most of the time. Using dispersion modeling, existing conditions in the project area were analyzed at the three intersections where traffic would have the greatest potential to generate high CO concentrations: the intersections of th Auburn Way South with “M” Street, Ellingson Road with East Valley Highway and Steward with 136 Avenue E. Because the intersection of Ellingson Road with “C” Street is located within 1000 feet of the intersection of Ellingson Road with East Valley Highway, these intersections were modeled together. Near these four intersections, dispersion modeling indicates the existing (2002) worst-case 1-hour CO concentrations are less than the NAAQS of 35 ppm. Applying the EPA-suggested persistence factor of 0.7 to the 1-hour CO concentrations reveals that 8-hour CO concentrations near these intersections would exceed the 9-ppm concentrations standard under worst-case conditions at one of the intersections examined. (See Table 1 in the Impacts section). Ozone Kersey III Residential Development Project10March 2, 2004 Air Quality Analysis Ozone is a highly reactive form of oxygen created by sunlight-activated chemical transformations of nitrogen oxides and volatile organic compounds (hydrocarbons) in the atmosphere. Unlike CO concentrations that tend to occur very close to the emission source(s), ozone problems tend to be regional. The atmospheric chemical reactions that produce ozone occur over time and during the lag time between emission and ozone formation, ozone precursors can be transported far from their sources. Transportation sources are one of a number of sources that produce the precursors to ozone. During the summer of 1990, ozone concentrations exceeded the 1-hour National Ambient Air Quality Standards (NAAQS) of 0.12 ppm several times at monitoring stations in both Enumclaw and Lake Sammamish State Park. As a result of these violations, the EPA designated all of Snohomish, King, and Pierce counties as a nonattainment area for ozone. In late 1992, the ozone nonattainment area was reduced to include all of Pierce County, all except a small portion in the northeast corner of King County, and the western portion of Snohomish County. The project study area is within the ozone nonattainment area established in 1992, but no ozone monitoring stations have violated the 1-hour ozone NAAQS since 1994 (EPA 2003). In 1997, the EPA redesignated the Puget Sound area to attainment for ozone and approved the associated air quality maintenance plan (Ecology 1997). This plan, which includes measures to continue controlling ozone emissions, is intended to assure that the standard is maintained for at least ten years. The project study area is, therefore, in an ozone air quality maintenance area. Under current air quality plans and policies, this status has no direct implications for the alternative plans being considered. Although a new, more stringent ozone standard has been adopted by the EPA, the new standard has not yet been fully implemented. Consequently, the Puget Sound region currently applies the older 1-hour average ozone standard of 0.12 ppm, which will likely be phased out after implementation of the new standard. PSCAA also is monitoring to assess compliance with the new 8-hour, 0.08-ppm standard. During the last three years, none of the Puget Sound region ozone monitoring stations have recorded any ozone concentrations that would comprise a violation of either the 1-hour or the 8-hour standards (PSCAA, 2004; EPA, 2004). Inhalable Particulate Matter (PM) 10 Federal, state, and local regulations set limits for particles less than or equal to about 10 micrometers in diameter. This fraction of particulate matter, called PM, is important in terms of potential human health 10 impacts, because particles this size can be inhaled deeply into human lungs. PM is generated by 10 industrial activities and operations, fuel combustion sources like residential wood burning, motor vehicle engines and tires, and other sources. Such sources occasionally cause high PM levels in the Puget 10 Sound region. Three areas in Seattle, Tacoma, and Kent have been declared nonattainment areas because PM concentrations sometimes exceed health standards. PSCAA has monitored particulate matter at 10 Alexander Avenue in Tacoma since 1987 (EPA 2004). The project area is not included in one of the three PM nonattainment areas in the Puget Sound region. 10 With the exception of an "unhealthy" local level of PM after Fourth of July fireworks in the Lake Forest 10 Park area, review of available data indicates that all recently measured PM concentrations have been 10 lower than the levels allowed by federal, state, and local PM standards (EPA 2004). 10 Because the proposed project is not located in a PM nonattainment area, a conformity evaluation for 10 PM is not required under current air quality rules. 10 Kersey III Residential Development Project11March 2, 2004 Air Quality Analysis Fine Particulate Matter (PM) 2.5 Effective September 16, 1997, the EPA adopted a new federal standard for particulate matter less than or equal to 2.5 micrometers (microns) in diameter (Table 1). This fine fraction of particulate matter mass is called PMa subset of PM. Such small particles (e.g., a typical human hair is about 100 microns in 2.5.,10 diameter) can be breathed deeply into the lungs and have been found to represent the most dangerous risk to human health. There are PMmonitoring stations located in Puyallup, Kent and “L” Stret in Tacoma.PM monitoring 2.5 2.5 data from all measurement locations in the Puget Sound region including data collected at the Duwamish monitor near the project site indicate particulate matter concentrations at all locations are complying with the short-term and the annual PM standards (PSCAA, 2004a and 2004b; EPA, 2004). 2.5 Health Effects Carbon Monoxide Carbon monoxide chemically combines with the hemoglobin in red blood cells to decrease the oxygen- carrying capacity of the blood. It also weakens the contractions of the heart, reducing the amount of blood pumped throughout the body. It can also affect the functioning of the lungs and brain. People with heart disease and pregnant women are especially at risk of the effects of carbon monoxide. Ozone Ozone is a pulmonary irritant that affects lung tissues and respiratory functions. Ozone impairs the normal function of the lungs and at higher concentrations (between 0.15 and 0.25 ppm), causes lung tightness, coughing and wheezing. People with chronic respiratory problems, such as asthma, seem most sensitive to ozone. Studies show that ozone also damages forests; particularly since ozone levels tend to be higher at the mountain elevations. PM and PM 102.5 Particulate matter consists of small, discrete solid or aerosol particles in the air. A PM particle is roughly 10 1/8 the diameter of a human hair, so it is invisible to the naked eye. PM is even smaller, and can be 2.5 inhaled even more deeply into the lungs. Motor vehicles, wood burning and industrial activity are major sources of particulate matter. Particulate matter in the respiratory tract may produce injury by itself, or it may act with gases to increase the effect on the body. The elderly, those suffering from respiratory illness, and young children are especially prone to the harmful effects of particulates. Particulate matter also makes long-distance views appear hazy. Kersey III Residential Development Project12March 2, 2004 Air Quality Analysis IMPACTS Impacts During Construction No Action Alternative With the No Action Alternative the project would not be built; therefore, no dust from excavation and grading would be added to ambient concentrations of suspended particulate matter as a result of the Kersey Development. In addition, heavy trucks, compressors and generators would not be used; therefore, local air quality degradation resulting from construction of the project would not occur. Action Alternative During construction of the various phases of this development, which would occur over a period of ___ years, dust from excavation and grading would contribute to ambient concentrations of suspended particulate matter. Construction contractor(s) would be required to comply with the PSCAA Regulation I, Section 9.15, which requires taking reasonable precautions to avoid dust emissions. Construction would require the use of heavy trucks and smaller equipment such as generators and compressors. These engines would emit air pollutants that would slightly degrade local air quality. Some construction phases would cause odors detectible to some people near the project site. This would be particularly true during paving operations using tar and asphalt. The construction contractor(s) would be required to comply with the PSCAA regulations requiring the best available measures to control the emissions of odor-bearing air contaminants to prevent emissions in sufficient quantities and of such characteristics and duration as is, or is likely to be, injurious to human health, plant or animal life, or property, or which unreasonably interferes with enjoyment of life and property. (Regulation I, Section 9.11). Such odors would be short-term. In addition, no slash burning would be permitted in association with the development of this project. Construction equipment, material hauling, and detours for excavation and grading could affect traffic flow in the project area. If construction delays traffic enough to significantly reduce travel speeds in the area, general traffic-related emissions would increase. Impacts During Operation The air pollutant of major concern for development projects that include a "transportation component" and that do not include other major emissions sources is CO. Of the various vehicular emissions that are subject to ambient air quality standards, CO is the pollutant emitted in the largest quantity. Therefore, CO concentrations are the primary focus of this analysis. As discussed above, because the proposed includes a transportation component that would affect one or more major roads in the vicinity, the project is subject to review under the state and federal air quality conformity rules. The dispersion modeling conducted for this analysis constitutes a project-level conformity study. Kersey III Residential Development Project13March 2, 2004 Air Quality Analysis Table 1 displays the results of the CAL3QHC dispersion modeling for existing conditions (2002) and the Action and No Action alternatives in the project's opening (2005) and design (2020) years. Modeling results are discussed following the table. Table 1. Calculated Maximum PM Peak-Period CO Concentrations (ppm) 2005 Opening Year2020 Design Year 2002 AveragingExisting NoActionNoAction IntersectionTimeYear ActionAction Alt 481Alt 700Alt 481Alt 700 Auburn Way 1-hour12.111.911.912.06.66.76.7 South with “M” Street 8-hour8.58.38.38.44.64.74.7 Ellingson 1-hour11.38.98.88.85.75.75.8 Road with East Valley 8-hour7.96.26.26.24.04.04.1 Highway Ellingson 1-hour13.29.910.010.06.26.36.4 Road with “C” 9.2 8-hour6.97.07.04.34.44.5 Street Steward Street 1-hour6.66.05.95.96.06.06.0 th with 136 8-hour4.64.24.14.14.24.24.2 Avenue E. Notes: Eight-hour concentrations were calculated from the modeled 1-hour CO concentration using a 0.7 persistence factor. Bolded entries indicate a result that exceeds the NAAQS for CO. Source: CAL3QHC dispersion modeling by MFG, Inc. No Action Alternative 2005–Opening Year: The No Action Alternative would not change the existing roadway or configurations of the intersections considered, but traffic in the area would increase due to population growth. Increasingly stringent emission reduction requirements and a continuing Vehicle Inspection and Maintenance Program cause the Mobile5b predicted 2005 vehicle emission rates to be lower than current emission factors. These lower emission rates offset the expected increases in CO that would be caused by larger traffic volumes and increased congestion by 2005. As a result, maximum calculated CO concentrations with the No Action Alternative are lower than predicted CO concentrations with existing conditions at all four of the intersections examined. The modeled 1-hour CO concentrations near these intersections are much less than the 35-ppm standard. In addition, the calculated worst-case 8-hour concentrations with No Action in 2005 are less than the 9-ppm standard at all four intersections. 2020– Design Year: In the design year, the configuration of the intersections examined would remain the th same as with existing conditions, with the exception of the intersection of Steward Road and 136 Avenue E. At this intersection, dedicated left-hand turn pockets would be constructed to mitigate traffic conditions. Owing to continuing improvements in vehicle engine efficiency and emission control programs, 2020 emission rates calculated by Mobile5b are much lower than current rates. So in spite of expected increases in peak-hour volumes by 2020 with the No Action Alternative, the maximum calculated CO Kersey III Residential Development Project14March 2, 2004 Air Quality Analysis concentrations near the examined intersections are also less than existing levels at all four intersections. In the design year, the modeled 1-hour and calculated 8-hour CO concentrations at the four intersections are far below the respective 35-ppm and 9-ppm ambient air quality standards. Action Alternatives 2005– Opening Year Alternative 481 : Modeling indicates worst-case CO concentrations near the four examined intersections would be equal to results observed without the project (No Action) at two of the four intersections examined. There would be a small decrease when compared to the No Action th Alternative at Steward Street and 136 Avenue E, where three additional left-turn pockets would be constructed. Nonetheless, all predicted future concentrations are less than both the 1-hour and the 8-hour CO standards. These results stem primarily from the expected continuing decreases in vehicle emission rates due to regulatory emission control requirements and continuation of the ongoing vehicle Inspection and Maintenance Program. This analysis indicates that Alternative 481 would be unlikely to result in significant air quality impacts in the opening year. 2005– Opening Year Alternative 700: Results observed with this alternative are identical to those expected with Alternative 481 , with one exception. At the intersection of Auburn Way South and “M” Street, there is a slight increase in the CO concentration. All results are less than the 1-hour and 8-hour CO NAAQS. This analysis indicates that Alternative 700 would be unlikely to result in significant air quality impacts in the opening year. 2020– Design Year Alternative 481 :Modeling indicates worst-case CO concentrations near two of the fourintersections examined would be only slightly higher with Alternative 481 in place when compared to the No Action Alternative in 2020. However, all predicted CO concentrations are well below both the 1-- hour and the 8-hour CO standards. Again, these results stem primarily from the expected continuing decreases in vehicle emission rates and continuation of the vehicle Inspection and Maintenance Program. This analysis indicate that Alternative 481 would be unlikely to result in significant air quality impacts in the design year. 2020– Design Year Alternative 700: The results for this alternative (similar to the results observed in the opening year) do not differ much from the results observed with the No Action alternative in place. Similarly, results are not dramatically different between this alternative and those seen with Alternative 481 . This may be due, in part, to the fact that there is only a slight volume increase associated with this higher-density alternative at the intersections examined.Because this is the case, predicted CO concentrations are well below both the 1-hour and the 8-hour CO standards. These findings indicate that Alternative 700 would be unlikely to result in significant air quality impacts in the design year. Indirect and Cumulative Impacts Because the transportation modeling that provided the data used in the air quality analysis considered expected traffic increases that would be caused by both the proposed project and other planned actions and growth in the area, both the traffic data and the air quality analysis effectively include consideration of the potential cumulative impacts of the proposed project. No further analysis is warranted. Kersey III Residential Development Project15March 2, 2004 Air Quality Analysis CONFORMITY WITH STATE IMPLEMENTATION PLAN The Federal Clean Air Act requires states to take actions to reduce air pollution in nonattainment areas so that federal health-based standards are not exceeded. States must also provide control measures in maintenance areas that will assure attainment for at least ten years. The framework for meeting these goals is the State Implementation Plan (SIP). As required by the Federal Clean Air Act, both Ecology, and the PSCAA submitted the ozone and the CO SIPs to the EPA for review; the plans were approved. Under section 176(c) of the Clean Air Act, as amended in 1990 and adopted by chapter 70.94 RCW of the Washington Clean Air Act of 1991, the PSRC, as the responsible metropolitan planning organization, and WSDOT cannot adopt, approve, or accept any transportation improvement plans, programs, or projects unless they conform to the Washington SIPs. Conformity with an SIP is defined as complying with the plan's intent to reduce or eliminate the number and severity of violations of an ambient air quality standard, and to achieve expeditious attainment of such standards. The federal and state rules and regulations governing conformity are described in 40 CFR parts 51 and 93 and in WAC 174-420. In accordance with the conformity guidelines, the PSRC was consulted on project conformance with existing transportation and air pollution control plans. The PSRC provided the following information (PSRC 2004). The arterial that is part of the proposed project is not included in the Metropolitan Transportation Plan (MTP) entitled Destination 2020, Metropolitan Transportation Plan for the Central Puget Sound Region. The regional plan was prepared and adopted by the PSRC, and reviewed by United States Department of Transportation. The plan meets all federal and state air quality conformity requirements. It is not known at this time whether the project will be included as an amendment to the MTP at a later date. The proposed project is not included in the newest Regional Transportation Improvement Program (RTIP) entitled 2003-05 Regional Transportation Improvement Program. The 2003-05 regional program, prepared and adopted by the PSRC, was reviewed by United States Department of Transportation. It was found to meet all federal and state air quality conformity requirements. It is not known at this time whether the project will be added as an amendment to the current RTIP. In many circumstances, a site-specific air quality analysis, which may include dispersion modeling, constitutes a "project-level" conformity review as defined in the clean air rules. For the proposed project, the modeling analysis described above represents a project-level review, and the following project-level conformity statement applies. Local CO concentrations related to the Action Alternatives A and B of the proposed project were predicted using approved regulatory models and protocol. With Alternative 481 in the project's opening year (2005), the maximum 8-hour CO concentration at the intersection of Auburn Way South with “M” Street would be 8.3 ppm, which is less than the 9 ppm 8-hour NAAQS. The maximum 8-hour CO concentration at this same intersection would be 8.4 ppm with Alternative 700 in place, also less than the 9 ppm NAAQS. By the design year (2020), the Alternatives A and B would result in even lower levels, and the predicted concentrations do not exceed the NAAQS. Predicted worst-case CO concentrations with both alternatives are 4.7 at the intersection of Auburn Way South and “M” Street and are well below the Kersey III Residential Development Project16March 2, 2004 Air Quality Analysis NAAQS. The proposed project, with either Action Alternative in place would not, therefore, create a new violation or worsen the current situation. At the project level, therefore, the project conforms with the purpose of the current SIP, and to all requirements of the Clean Air Act Amendments of 1990 and the Washington State Clean Air Act of 1991. MITIGATION Mitigation During Construction The following is a list of possible mitigation measures that could be implemented to reduce potential impacts from vehicle exhaust and fugitive dust during construction of the project. This list was developed from control measures and best management practices suggested by the Associated General Contractors of Washington (AGC Guide to Handling Fugitive Dust From Construction Projects). Use only equipment and trucks that are maintained in optimal operational condition ! Require all off road equipment to be retrofit with emission reduction equipment ! Use bio diesel or other lower-emission fuels for vehicles and equipment ! Use car pooling or other trip reduction strategies for construction workers ! Stage construction to minimize overall transportation system congestion and delays to reduce ! regional emissions of pollutants during construction Implement restrictions on construction truck idling (e.g., limit idling to a maximum of 5 minutes) ! Locate construction equipment away from sensitive receptors such as fresh air intakes to ! buildings, air conditioners, and sensitive populations Locate construction staging zones where diesel emissions won't be noticeable to the public or near ! sensitive populations such as the elderly and the young Develop a dust control plan during project planning to identify sources and activities that would be ! likely to generate fugitive dust and the means to control such emissions Spray exposed soil with water or other suppressant to reduce emissions of PM10 and deposition ! of particulate matter; include dust controls on paved and unpaved roads and in site preparation, grading and loading areas Cover or use moisteners or soil stabilizers to minimize emissions from storage piles; minimize drop ! heights involved in creating storage piles or haul-vehicle loading Cover all trucks transporting materials, wetting materials in trucks, or providing adequate ! freeboard (space from the top of the material to the top of the truck bed), to reduce PM10 emissions and deposition during transport Kersey III Residential Development Project17March 2, 2004 Air Quality Analysis Pave or use gravel on staging areas and roads that would be exposed for long periods, and reduce ! speeds on unpaved roads or work areas Use quarry spalls (rock entrances), vehicle scrapes, or wheel washers to remove particulate ! matter that would otherwise be carried off site by vehicles to decrease deposition of particulate matter on area roadways Remove particulate matter deposited on paved, public roads, sidewalks, and bicycle and pedestrian ! paths to reduce mud and dust; sweep and wash streets continuously to reduce emissions Cover dirt, gravel, and debris piles as needed to reduce dust and wind blown debris, and avoid ! dust-generating activities during windy periods Route and schedule construction trucks to reduce delays to traffic during peak travel times to ! reduce air quality impacts caused by a reduction in traffic speeds Mitigation During Operation Because the air quality modeling analysis did not indicate the potential for significant air quality impacts related to the proposed project, mitigation measures are not proposed or warranted. Significant Unavoidable Adverse Impacts No significant unavoidable adverse air quality impacts have been identified with this air quality analysis to result from the proposed project, and none would be expected. Kersey III Residential Development Project18March 2, 2004 Air Quality Analysis REFERENCES Transportation Solutions, Inc. (TSI) 2004. Los Traffic Data Sheets. Puget Sound Clean Air Agency (PSCAA) 2003General information. Seattle, Washington. Web Page: . Assessed May 2003. Puget Sound Regional Council (PSRC) 2003Tier II Adjusted Mobile5b CO Emission Factors. Provided to MFG, Inc. by Kelly McGourty, Puget Sound Regional Council, May 2003. 2004Web page – general information : . Accessed May 2003. U.S. Environmental Protection Agency (EPA) 1992aUser's Guide to CAL3QHC Version 2.0: A Modeling Methodology for Predicting Pollutant Concentrations Near Roadway Intersections. Office of Air Quality planning and Standards, Technical Support Division, Research Triangle Park, N.C. November, 1992. EPA-454/R-92-006 1992bGuideline for Modeling Carbon Monoxide From Roadway Intersections. Office of Air Quality planning and Standards, Technical Support Division, Research Triangle Park, N.C. November, 1992. EPA-454/R-92-005 2004AirData web page: Washington State Department of Ecology (Ecology) 1997Communicating Air Quality: Washington's 1995-1996 Air Quality Annual Report. Air Quality Program, Lacey, Washington. Publication number 96-217. Kersey III Residential Development Project19March 2, 2004 Air Quality Analysis