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HomeMy WebLinkAbout4 2 Air Quality 4.2 AIR QUALITY 4.2.1 Introduction This section describes the emissions of air pollutants expected during the construction and occupancy phases of the development envisioned by the project. Air pollutants are primarily generated by two categories of sources: stationary and mobile. Stationary sources include "point sources," which have one or more emission sources at a single facility, and "area sources," which are widely distributed and produce many small emissions. Point sources are usually associated with manufacturing and industrial uses; area sources include residential water heaters, lawn mowers, landfills, and consumer products such as barbecue lighter fluid. Mobile sources are non-stationary sources such as motor vehicles. This section was prepared in accordance with the December 1999 Bay Area Air Quality Management District (BAAQMD) California Environmental Quality Act (CEQA) Guidelines. 4.2.2 Environmental Setting 4.2.2.1 Regional Climate and Topography The project area is located in the San Francisco Bay Area Air Basin (the Basin). The topography and climate of the Basin combine to make it an area in which poor air quality could occur. The climate of the Bay Area is Mediterranean in character, with mild, rainy winter weather from November through March and warm, dry weather from June through October. In summer, the Pacific high- pressure system typically remains near the coast of California; subsidence of warm air over the cooler marine air associated with the Pacific high creates frequent summer atmospheric temperature inversions. Subsidence inversions may be several hundred to several thousand feet deep, effectively trapping pollutants in a stagnant volume of air near the ground with little dispersion ability. In winter, the Pacific high-pressure system moves southward, allowing ocean-formed storms to move through the region. The frequent storms and infrequent periods of sustained sunny weather are not conducive to ozone formation. Radiational cooling during the evening, however, sometimes creates thin inversions and concentrates air pollutant emissions near the ground. Impact Sciences, Inc. 868-01 4.2 -1 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality 4.2.2.2 The City of South San Francisco (the City) is located on the Peninsula, an area that extends from northwest San Jose to the Golden Gate Bridge in San Francisco. The Santa Cruz Mountains, as part of the Pacific Coast Ranges, extend north from the center of the Peninsula adjacent to the City. The Santa Cruz Mountains create a rain shadow on the western side as moist marine air travels over peaks that range in elevation from 2,000 feet to 500 feet. The San Bruno Gap lies north of the City and extends from the ocean on the west to the San Francisco International Airport to the east. The City is bounded by the City of Brisbane to the north and the City of San Bruno to the south, and is located along major transportation routes including U.S. 101, Interstate 380, Interstate 280, and the Union Pacific Railroad. The Santa Cruz Mountains greatly influence the Peninsula's climate. Since the average elevation of South San Francisco is below 200 feet, the marine layer flows across the city, making its climate cool and windy. The blocking effect of the Santa Cruz Mountains can be seen in the summertime maximum temperatures. In this part of the Peninsula, the mean maximum temperatures are low 80s degrees Fahrenheit (F) during the summer and low 60s during the winter. Mean minimum temperatures range from high 50s in the summer to the low 40s in the winter (BAAQMD, undated). Annual average wind speeds range from 5 to 10 mph throughout the Peninsula. Since the San Bruno Gap is oriented in the same northwest to southeast direction as the prevailing winds, it commonly allows the marine layer to pass across the peninsula. Prevailing winds in South San Francisco are westerly. Also, because the elevations along the gap are less than 200 feet, marine air is easily able to penetrate into the bay. Rainfall amounts on the east side of the peninsula are somewhat lower than on the west side with San Francisco and Redwood City reporting an average of 19.5 inches per year. On the west side, Half Moon Bay reports 25 inches per year. Regional Air Quality To identify ambient concentrations of the criteria pollutants the BAAQMD operates 31 air quality monitoring stations throughout the Basin. The nearest monitoring station to the project site is located at 10 Arkansas Street Station in San Francisco, at which carbon monoxide (CO), sulfur dioxide (S02), nitrogen Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2-2 4.2 Air Quality 4.2.2.3 dioxide (N02), ozone (03), particulate matter of 10 micrometers in diameter or smaller (PMlO), and particulate matter of 2.5 micrometers in diameter or smaller (PM2.5), among other air pollutants, are monitored. Table 4.2-1, Ambient Pollutant Concentrations Measured at San Francisco- Arkansas Street, lists the concentrations registered and the exceedances of California Ambient Air Quality Standards (CAAQS) and the National Ambient Air Quality Standards (NAAQS) that have occurred at this monitoring station from 2001 through 2005. During this period, the station registered one day above the I-hour state standard for 03, 84 days above the 24-hour state standard for particulate matter less than 10 microns (PMlO) and six days above the 24-hour federal standard for particulate matter less than 2.5 microns (PM2.5). No other exceedances of the state or federal standards were registered at this station between 2001 and 2005. Local Air Quality South San Francisco South San Francisco is largely comprised of single-use areas, with industry, office/research, and development/commercial/industrial in the eastern and southeastern portions of the city, single-family homes to the north and west, commercial uses along a few transportation corridors, and multi-family housing clustered in those same corridors and on hillsides. The project site is surrounded by sites zoned for planned industrial and research and development uses, and by the Genentech campus. Major roadways traversing South San Francisco in the vicinity of the project site include U.S. 101, 1-280, 1-380, and El Camino Real, which experience relatively high pollutant concentrations due to heavy traffic volumes, particularly during peak periods. South San Francisco enjoys generally good air quality, due largely to the presence of the San Bruno Gap, a break in the Santa Cruz Mountains that allows onshore winds to flow easily into San Francisco Bay and quickly disperse air pollutants. Although South San Francisco's pollutant emissions are high, winds are generally fast enough to carry the pollutants away before they can accumulate (BAAQMD, undated). Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2-3 4.2 Air Quality The San Francisco International Airport lies within two miles of the project vicinity and is a source of air pollutants. The point and area sources associated with this facility include a sludge gas burner, high temperature hot water generator, reverse airflow auto-track spray booth, and diesel field lighting generators. In addition, mobile source emissions include jets, mobile equipment, and motor vehicles associated with airport operations. This facility and other neighboring land uses generate mobile source emissions that are associated with motor vehicle trips. The BAAQMD maintains an inventory of stationary sources of toxic air contaminants in the Bay Area. According to the Emissions Inventory 2002 Annual Report, major stationary emissions sources in the vicinity of the project site include the South San Francisco-San Bruno Wastewater Treatment Plant, the Shell Oil Company Distribution Plant, and the Superior Aluminum Body Corporation. There are also 12 dry cleaners in South San Francisco (BAAQMD 2004). However, none of these stationary emission sources is within 1 mile of the project vicinity. Table 4.2-1 Ambient Pollutant Concentrations Measured at San Francisco-Arkansas Street Station by Year OZONE (03) Maximum I-hour concentration (ppm) 0.082 0.054 0.085 0.093 0.058 Maximum 8-hour concentration (ppm) 0.054 0.049 0.059 0.059 0.054 Number of days exceeding state I-hour standard 0.09 ppm 0 0 0 1 0 Number of days exceeding federa18-hour 0.08 ppm 0 0 0 0 0 standard CARBON MONOXIDE (CO) Maximum I-hour concentration (ppm) 4.0 3.5 3.6 2.9 2.5 Maximum 8-hour concentration (ppm) 3.3 2.6 2.84 2.21 2.09 Number of days exceeding federa18-hour 9ppm 0 0 0 0 0 standard Number of days exceeding state 8-hour standard 9.0 ppm 0 0 0 0 0 NITROGEN DIOXIDE (NOz) Maximum I-hour concentration (ppm) 0.073 0.075 0.072 0.063 0.066 Annual Average (ppm) 0.019 0.019 0.018 0.017 0.016 Number of days exceeding state I-hour standard 0.25 ppm 0 0 0 0 0 Impact Sciences, Inc. 868-01 4.2-4 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality SULFUR DIOXIDE (SOz) Maximum I-hour concentration in ppm 0.025 0.053 0.024 0.044 0.019 Maximum 24-hour concentration in ppm 0.007 0.006 0.007 0.008 0.007 Annual arithmetic mean concentration (ppm) 0.002 0.002 0.002 0.002 0.002 Number of days exceeding state I-hour standard 0.25 ppm 0 0 0 0 0 Number of days exceeding state 24-hour standard 0.04 ppm 0 0 0 0 0 Number of days exceeding federal 24-hour 0.14 ppm 0 0 0 0 0 standard PARTICULATE MATTER (PMlo) Maximum 24-hour concentration (~g/m3)Z 69.8 78.6 51.7 51.8 46.4 Maximum 24-hour concentration (~g/m3)3 67.4 74.1 50.8 48.6 44.6 Annual arithmetic mean concentration (~g/m3)3 26 25 22 22 19 Number of samples exceeding federal 24-hour 150 ~g/m3 0 0 0 0 0 standard Number of samples exceeding state 24-hour 50 ~g/m3 8 4 1 1 0 standard PARTICULATE MATTER (PMz.s) Maximum 24-hour concentration (~g/m3) 77 70 41.6 45.8 43.6 State and National Annual Average Annual 11.5 13.1 10.2 9.9 9.5 arithmetic mean concentration (~g/m3) Number of samples exceeding federal 24-hour 65 ~g/m3 2 4 0 0 0 standard4 LEAD Maximum 30-day average concentration (~g/m3) 0.02 0.02 0.01 Maximum quarterly average concentration 0.01 0.01 0.01 (~g/m3) Number of months exceeding state standard 1.5 ~g/m3 0 0 0 Sources: (0 California Air Resources Board Air Quality Database http://www.arb.ca.gov/adam/welcome.html (iO U.S. Environmental Protection Agency Air Quality Database http://www.epa.gov/air/data/ 1 Parts by volume per million of air (ppm), micrograms per cubic meter of air (flg/m3) or annual arithmetic mean (aam). Using State methods for sampling. Using federal methods for sampling. The federal PM2.5 standard was revised from 65 to 35 flg/m3 in September 2006. Statistics shown are based on the 65 flg/m3 standard NOTES: -Sulfates are monitored at Arkansas Street Station, San Francisco. Sulfates have not exceeded the state standard of 25 flg/m3 for more than 20 years. - The BAAQMD has established a temporary special study monitoring station (i.e., Hunters Point station) at 100 Whitney Young Circle for a Children's Environmental Impact Program during 2004 and 2005. Although the temporary monitoring station was closer to the proposed project than the Arkansas Street station, air monitoring data was only collected for a portion of 2004 and 2005 and therefore are not representative of a full year's data for either monitoring year. Accordingly, the data shown above is from the Arkansas Street station Impact Sciences, Inc. 868-01 4.2 -5 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality Sensitive Receptors Land uses such as schools, hospitals and convalescent homes are considered to be relatively sensitive to poor air quality because infants and children, the elderly, and people with health afflictions, especially respiratory ailments, are more susceptible to respiratory infections and other air-quality-related health problems than the general public. Residential areas are also considered to be sensitive to air pollution because residents (including children and the elderly) tend to be at home for extended periods of time, resulting in sustained exposure to any pollutants present. In the vicinity of the project site, sensitive receptors would include children using the daycare center that is proposed as part of the Genentech Master Plan that, if approved, would be located adjacent to the project site, at 444 Allerton Avenue. Localized Carbon Monoxide Concentrations Traffic-congested roadways and intersections have the potential to generate localized high levels of co. The BAAQMD monitoring stations have not recorded any exceedances of the state or federal co standards since 1991. However, because elevated co concentrations are generally localized, heavy traffic volumes and congestion at specific intersections or roadway segments can lead to high levels of CO, or hot spots, while concentrations at the nearest air quality monitoring station may be below state and federal standards. Site-Specific Emissions The project site currently consists of approximately 7.48 acres that, except for an existing paved parking lot, are undeveloped. No structures are currently located on the site, but the site does include various mature trees and landscaping, many of which would be preserved with development of the proposed project. Since the site is vacant, there are no significant site-specific emission sources at the present. Impact Sciences, Inc. 868-01 4.2-6 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality 4.2.2.4 Toxic Air Contaminants Federal Regulation of toxic air contaminants (TACs), termed Hazardous Air Pollutants (HAPs) under federal regulations, is achieved through federal and state controls on individual sources. Federal law defines HAPs as noncriteria air pollutants with short-term (acute) and/or long-term (chronic or carcinogenic) adverse human health effects. The 1990 federal Clean Air Act (CAA) Amendments offer a comprehensive plan for achieving significant reductions in both mobile and stationary source emissions of HAPs. Under the 1990 CAA Amendments, a total of 189 chemicals or chemical families were designated HAPs because of their adverse human health effects. Title III of the 1990 federal CAA Amendments amends Section 112 of the CAA to replace the former program with an entirely new technology-based program. Under Title III, the u.s. Environmental Protection Agency (U.S. EP A) must establish maximum achievable control technology emission standards for all new and existing "major" stationary sources. Major stationary sources of HAPs are required to obtain an operating permit from the BAAQMD pursuant to Title V of the 1990 CAA Amendments. State California law defines TACs as air pollutants having carcinogenic or other health effects. Assembly Bill (AB) 1807 (the Tanner Bill, passed in 1983) established the State Air Toxics Program and the methods for designating certain chemicals as T ACs. A total of 245 substances have been designated T ACs under California law; they include the (federal) Hazardous Air Pollutants (HAPs) adopted as TACs in accordance with AB 2728. The Air Toxics Hot Spots Information and Assessment Act of 1987 (AB 2588) seeks to identify and evaluate risk from air toxics sources; AB 2588 does not regulate air toxics emissions directly. Under AB 2588, sources emitting more than 10 tons per year of any criteria air pollutant must estimate and report their toxic air emissions to the local air districts. Local air districts then prioritize facilities on the basis of emissions, and high priority facilities are required to submit a health risk assessment and communicate the results to the affected public. Depending on risk levels, emitting facilities are required to implement varying levels of risk reduction measures. The BAAQMD is responsible for implementing AB 2588 in the Basin. Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 -7 4.2 Air Quality The BAAQMD is currently working to control TAC impacts from local hot spots and from ambient background concentrations. The control strategy involves reviewing new sources to ensure compliance with required emission controls and limits, maintaining an inventory of existing sources to identify major TAC emissions and developing measures to reduce TAC emissions. The BAAQMD publishes the results of the various control programs in an annual report, which provides information on the current T AC inventory, AB 2588 risk assessments, TAC monitoring programs and TAC control measures and plans. The BAAQMD Toxic Air Contaminant Control Program Annual Report 2002 (BAAQMD, June 2004) identified 16 stationary sources of TACs in South San Francisco, including 12 dry cleaners; Cycle Shack, Inc.; Olympian Oil; Shell Oil Company Distribution Plant; and the South San Francisco-San Bruno Water Quality Plant. The dry cleaners emit perchloroethylene, which is a dry-cleaning solvent, the Cycle Shack emits hexavalent chromium, the oil company facilities emit benzene, and the water quality plant emits benzene, chloroform, dichlorobenzene, perchloroethylene, and trichloroethylene. One of the T ACs being controlled by the BAAQMD is particulate matter (PM) from diesel-fueled engines, also known as diesel exhaust particulate. In 1998, the California Air Resources Board (CARB) identified diesel exhaust particulate as a TAC. Compared to other TACs, diesel exhaust particulate emissions are estimated to be responsible for about 70 percent of the total ambient air toxics risk. On a statewide basis, the average potential cancer risk associated with these emissions is over 500 potential cancer cases per million exposed people. In addition to these general risks, diesel exhaust particulate can also present elevated localized or near-source exposures. Depending on the activity and nearness to receptors, these potential risks can range from small to 1,500 cancer cases per million exposed people (California Air Resources Board 2000). 4.2.3 Regulatory Considerations Air quality within the San Francisco Bay Area Air Basin is addressed through the efforts of various federal, state, regional and local government agencies. These agencies work jointly as well as individually to improve air quality through legislation, regulations, planning, policymaking, education, and a variety of Impact Sciences, Inc. 868-01 4.2-8 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality 4.2.3.1 programs. The agencies primarily responsible for improving the air quality within the Basin are discussed below along with their individual responsibilities. u.s. Environmental Protection Agency The U.S. EP A is responsible for enforcing the 1990 Amendments to the federal CAA and the federal ambient air quality standards that it establishes. The NAAQS identify levels of air quality for seven criteria pollutants that are considered the maximum levels of ambient (background) air pollutants considered safe, with an adequate margin of safety, to protect the public health and welfare. The seven criteria pollutants are 03, CO, N02, S02, respirable particulate matter (PMlO), fine particulate matter (PM2.5), and lead. Particulate matter is the general term used for a mixture of solid particles and liquid droplets found in the air. For air quality purposes, these particles are classified by size: fine particulates (PM2.5) have a diameter less than or equal to 2.5 micrometers, and respirable or coarse particulates (PMlO) have a diameter less than or equal to 10 micrometers. The federal ambient air quality standards and the relevant health effects of the criteria pollutants are summarized in Table 4.2-2, Ambient Air Quality Standards. The Basin is currently classified by the u.s. EP A as a nonattainment/marginal area for the 8-hour standard for 03 (the I-hour standard was revoked as of June 15, 2005). Additionally, it has been designated as an attainment/unclassifiable area for the I-hour and 8-hour standards for CO; the 24-hour and annual standards for S02, PMlO and PM2.5; the annual standard for N02; and as an attainment area for the quarterly lead standard (U.S. EP A 2004). In response to its enforcement responsibilities, the u.s. EP A requires each state to prepare and submit a State Implementation Plan (SIP) describing how the state will achieve the federal standards by specified dates, depending on the severity of the air quality within the state or air basin. Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2-9 4.2 Air Quality Table 4.2-2 Ambient Air Quality Standards Ozone 0.070 ppm, 8-hr. avg. 0.08 ppm, 8-hr avg. (a) Short-term exposures: (1) Pulmonary 0.09 ppm, I-hr avg. (3-year average of function decrements and localized lung annual 4th-highest edema in humans and animals; and (2) Risk daily maximum) to public health implied by alterations in pulmonary morphology and host defense in animals; (b) Long-term exposures: Risk to public health implied by altered connective tissue metabolism and altered pulmonary morphology in animals after long-term exposures and pulmonary function decrements in chronically exposed humans; (b) Vegetation damage; and (c) Property damage Carbon Monoxide 9.0 ppm, 8-hr avg. 9 ppm, 8-hr avg. (a) Aggravation of angina pectoris and 20 ppm, I-hr avg. 35 ppm, I-hr avg. other aspects of coronary heart disease; (b) Decreased exercise tolerance in persons with peripheral vascular disease and lung disease; (c) Impairment of central nervous system functions; and (d) Possible increased risk to fetuses Nitrogen Dioxide 0.25 ppm, I-hr avg. 0.053 ppm, annual (a) Potential to aggravate chronic respiratory arithmetic mean disease and respiratory symptoms in sensitive groups; (b) Risk to public health implied by pulmonary and extra-pulmonary biochemical and cellular changes and pulmonary structural changes; and (c) Contribution to atmospheric discoloration Sulfur Dioxide 0.04 ppm, 24-hr avg. 0.030 ppm, annual (a) Bronchoconstriction accompanied by 0.25 ppm, I-hr avg. arithmetic mean symptoms which may include wheezing, 0.14 ppm, 24-hr avg. shortness of breath and chest tightness, during exercise or physical activity in person with asthma Respirable 20 ~g/m3, annual 150 ~g/m3, 24-hr avg. (a) Excess deaths from short-term exposures Particulate Matter arithmetic mean and exacerbation of symptoms in sensitive (PMlO ) 50 ~g/m3, 24-hr avg. patients with respiratory disease; and (b) Excess seasonal declines in pulmonary function, especially in children Impact Sciences, Inc. 868-01 4.2 -10 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality Fine Particulate 12 ~g/m3, annual 15 ~g/m3, annual (a) Increased hospital admissions and Matter (PM2.5) arithmetic mean arithmetic mean emergency room visits for heart and lung (3-year average) disease; (b) Increased respiratory symptoms 35 ~g/m3, 24-hr avg. and disease; and (c) Decrease lung functions (3-year average of and premature death 98th percentile) Sulfates 25 ~g/m3, 24-hr avg. None (a) Decrease in ventilatory function; (b) Aggravation of asthmatic symptoms; (c) Aggravation of cardio-pulmonary disease; (d) Vegetation damage; (e) Degradation of visibility; and (f) Property damage Lead* 1.5 ~g/m3, 30-day 1.5 ~g/m3, calendar (a) Increased body burden; and avg. quarterly average (b) Impairment of blood formation and nerve conduction Visibili ty - Red ucing In sufficient amount None Visibility impairment on days when relative Particles to produce humidity is less than 70 percent extinction of 0.23 per kilometer due to particles when relative humidity is less than 70o~, 8- hour average (10 AM - 6 PM) Hydrogen Sulfide 0.03 ppm, 1-hr avg. None Odor annoyance Viny I Chloride* 0.01 ppm, 24-hr avg. None Known carcinogen Source: California Air Resources Board. "Air Quality Standards." [Online] [November 10, 2006]. <http://www.arb.ca.gov/aqs/ aaqs2.pdf>. South Coast Air Quality Management District. Final Program Environmental Impact Report to the 2003 Draft AQMP (Diamond Bar, California: South Coast Air Quality Management District, August 2003), Table 3.1-1, p. 3.1-2. This report may be reviewed on the SCAQMD website at http://www.aqmd.gov/ceqa/documents/2003/aqmd/finaIEA/aqmp/ AQMP _FEIR.html. Notes: J-lg/m3 = microgram per cubic meter. ppm = parts per million by volume. * The CARB has identified lead and vinyl chloride as "toxic air contaminants" with no threshold level of exposure for adverse health effects determined. These actions allow for the implementation of control measures at levels below the ambient concentrations specified for these pollutants. Impact Sciences, Inc. 868-01 4.2 -11 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality 4.2.3.2 California Air Resources Board The CARB, a branch of the California Environmental Protection Agency (Cal/EP A), oversees air quality planning and control throughout California. It is primarily responsible for ensuring implementation of the 1989 California Clean Air Act (CCAA), for responding to the federal CAA requirements and for regulating emissions from motor vehicles and consumer products within the state. The CARB has established emission standards for vehicles sold in California and for various types of equipment available commercially. It also sets fuel specifications to further reduce vehicular emissions. Like the u.s. EP A, the CARB has established ambient air quality standards for the state (CAAQS). These standards apply to the same seven criteria pollutants as the federal CAA and also address sulfates (S04), visibility-reducing particles, hydrogen sulfide (H2S) and vinyl chloride (C2H3Cl). The CCAA standards are more stringent than the federal standards and, in the case of PMlO and S02, far more stringent. The CCAA requires air pollution control districts to achieve the state standards by the earliest practicable date. The California ambient air quality standards and the relevant health effects of the criteria pollutants are summarized in Table 4.2-2. Based on monitored pollutant levels, the CCAA divides 03 nonattainment areas into four categories-moderate, serious, severe, and extreme-to which progressively more stringent planning and emission control requirements apply. The Basin is a serious nonattainment area for the California I-hour ozone standard. While the Basin is designated as nonattainment with respect to the California 8-hour standard, the CARB has not yet made area classifications for the new 8-hour ozone standard; however, the new classifications are expected to be equal to or worse than the previous I-hour classifications. In regard to particulate matter, the Basin is designated as nonattainment for the California 24-hour and annual PMlO standards, as well as the California annual PM2.5 standard. The Basin is designated as attainment or unclassifiable for all other CAAQS. The ozone precursors, reactive organic gases (ROG) and oxides of nitrogen (NOx), in addition to PMlO, are the pollutants of concern for projects located in the BAAQMD. Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2-12 4.2 Air Quality 4.2.3.3 Bay Area Air Quality Management District Management of air quality in the Basin is the responsibility of the BAAQMD. The BAAQMD is responsible for bringing and/or maintaining air quality in the Basin within federal and air quality standards. Specifically, the BAAQMD has responsibility for monitoring ambient air pollutant levels throughout the Basin and developing and implementing attainment strategies to ensure that future emissions will be within federal and state standards. Clean Air Plans As discussed previously, the federal and California Clean Air Acts require preparation of plans to reduce air pollution to healthful levels. The BAAQMD has responded to this requirement by preparing a series of Clean Air Plans (CAPs), the most recent and rigorous of which was approved in December 2000. The 2000 CAP continues the air pollution reduction strategy established by the 1991 CAP and represents the third triennial update to the 1991 CAP, following previous updates in 1994 and 1997. The 2000 CAP is designed to address attainment of the state standard for 03. The 1997 CAP contained stationary and mobile source control measures, which included developing rules to reduce vehicle trips to and from major residential developments, shopping centers and other indirect sources; encouraging cities and counties to plan for high-density development; and clustering development with mixed uses in the vicinity of mass transit stations. The 2000 CAP includes changes in the organization and scheduling of some existing control measures, some new stationary source control measures, revisions to previous stationary source measures and deletion of some control measures deemed no longer feasible by BAAQMD staff. The transportation control measures (TCMs) in the 2000 CAP are unchanged from the 1997 CAP. The 2000 CAP continues to discourage urban sprawl while strongly endorsing high-density mixed-use developments near transit centers that reduce the need for commuting by personal vehicles. BAAQMD Rules and Regulations The BAAQMD is responsible for limiting the amount of emissions that can be generated throughout the Basin by stationary sources. Specific rules and Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2-13 4.2 Air Quality 4.2.3.4 regulations have been adopted that limit emissions that can be generated by various uses and/or activities and identify specific pollution reduction measures that must be implemented in association with various uses and activities. These rules regulate not only the emissions of the state and federal criteria pollutants, but also the emissions of toxic and acutely hazardous materials. The rules are also subject to ongoing refinement by the BAAQMD. Emissions sources subject to these rules are regulated through the BAAQMD's permitting process. Through this permitting process, the BAAQMD also monitors the amount of stationary emissions being generated and uses this information in developing the CAP. Stationary emission sources that would be constructed as part of the project may be subject to the BAAQMD rules and regulations. BAAQMD CEQA Guidelines In April 1996, the BAAQMD prepared its BAAQMD CEQA Guidelines as a guidance document to provide lead government agencies, consultants and project proponents with uniform procedures for assessing air quality impacts and preparing the air quality sections of environmental documents for projects subject to CEQA. The BAAQMD CEQA Guidelines were revised by the BAAQMD in December 1999. This document describes the criteria that the BAAQMD uses when reviewing and commenting on the adequacy of environmental documents, such as this DEIR. The BAAQMD CEQA Guidelines recommend thresholds for use in determining whether projects would have significant adverse environmental impacts, identify methodologies for predicting project emissions and impacts, and identify measures that can be used to avoid or reduce air quality impacts. This DEIR section was prepared following these recommendations. Association of Bay Area Governments The Association of Bay Area Governments (ABAG) is a council of governments for the Counties of Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, Santa Clara, Sonoma and Solano. ABAG is a regional planning agency and serves as a forum for regional issues relating to transportation, the economy, community development and the environment. ABAG also serves as the Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 -14 4.2 Air Quality 4.2.3.5 regional clearinghouse for projects requiring environmental documentation under federal and state law. In this role, ABAG reviews proposed projects to analyze their impacts on ABAG's regional planning efforts. Although ABAG is not an air quality management agency, it is responsible for several air quality planning issues. Specifically, as the designated Metropolitan Planning Organization (MPO) for the nine counties, it is responsible, pursuant to Section 176(c) of the 1990 Amendments to the federal CAA, for providing current population, employment, travel and congestion projections for regional air quality planning efforts. ABAG is required to quantify and document the demographic and employment factors influencing expected transportation demand, including land-use forecasts. ABAG is also responsible for preparing and approving the portions of the Basin's Clean Air Plan (CAP) relating to demographic projections and integrated regional land use, housing and employment, as well as transportation programs, measures, and strategies. Local Governments Local governments, such as the City of South San Francisco, have the authority and responsibility to reduce air pollution through their police power and land- use decision-making authority. Specifically, local governments are responsible for the mitigation of emissions resulting from land-use decisions and for the implementation of transportation control measures (TCMs) as outlined in the CAP. The CAP assigns local governments certain responsibilities to assist the Basin in meeting air quality goals and policies. Their responsibility is accomplished by identifying air quality goals, policies, and implementation measures in their general plans. Through capital improvement programs, local governments can require infrastructure that contributes to improved air quality, such as ridesharing, park-and-ride, bicycle facilities, and traffic signal and signal timing improvements. In accordance with CEQA requirements and the CEQA review process, local governments assess air quality impacts, require mitigation of potential air quality impacts by conditioning discretionary permits, and monitor and enforce implementation of such mitigation. Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2-15 4.2 Air Quality City of South San Francisco 1999 General Plan The 1999 General Plan includes policies that address how the City will participate in programs to maintain and improve air quality. The following policies may be relevant to the proposed project: Policy 7.3-G-1 Policy 7.3-G-2 Policy 7.3-G-3 Policy 7.3-G-4 Policy 7.3-]-1 Policy 7.3-]-2 Policy 7.3-]-3 Continue to work toward improving air quality and meeting all national and state ambient air quality standards and by reducing the generation of air pollutants both from stationary and mobile sources, where feasible. Encourage land use and transportation strategies that promote use of alternatives to the automobile for transportation, including bicycling, bus transit, and carpooling. Minimize conflicts between sensitive receptors and emissions generators by distancing them from one another. Cooperate with the Bay Area Air Quality Management District to achieve emissions reductions for nonattainment pollutants and their precursors, including carbon monoxide, ozone, and PM-10, by implementation of air pollution control measures as required by state and federal statutes. Cooperate with the Bay Area Air Quality Management District to achieve emissions reductions for nonattainment pollutants and their precursors, including carbon monoxide, ozone, and PM-10, by implementation of air pollution control measures as required by state and federal statutes. Use the City's development review process and the California Environmental Quality Act (CEQA) regulations to evaluate and mitigate the local and cumulative effects of new development on air quality. Adopt the standard construction dust abatement measures included in BAAQMD CEQA Guidelines. Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 -16 4.2 Air Quality Policy 7.3-1-4 Require new residential development and remodeled existing homes to install clean-burning fireplaces and wood stoves. Policy 7.3-1-5 In cooperation with local conservation groups, institute an active urban forest management program that consists of planting new trees and maintaining existing ones. 4.2.4 Consistency with Applicable Regulations As a matter of law, the development envisioned by the project is required to comply with all federal, state and BAAQMD regulations pertaining to emissions of air pollutants. As described in Subsection 4.2.5, Impacts and Mitigation, the construction activities associated with implementing the project must comply with applicable regulations including those governing control of fugitive dust, application of asphalt paving materials, and application of architectural coatings. While few of these regulations would apply to operation of the project, as most of these regulations apply to stationary sources of air pollutants, the developers and occupants would have to comply with the relevant air quality regulations. In addition, inhabitants of the project would have to comply with state regulations governing consumer products, motor vehicle fuel, and motor vehicle inspection and maintenance (smog check) programs. As appropriate, consistency with the air quality policies contained in the City of South San Francisco's General Plan, as outlined in Subsection 4.2.3.5, Local Governments, must be achieved. Most of these policies apply to goals and actions to be taken by the City on a broader scale than for the project site. Accordingly, they are not directly applicable to the project because of its site- specific focus. Those measures dealing with specific development details that are not a part of the project will be considered by the City during their review of more detailed development plans. 4.2.5 Impacts and Mitigation 4.2.5.1 Significance Criteria The Environmental Checklist adopted by the City of South San Francisco lists criteria to be considered when determining whether a project could have significant air quality impacts. In addition, BAAQMD CEQA Guidelines contain Impact Sciences, Inc. 868-01 4.2 -17 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality similar air quality thresholds. The City's thresholds rely on Appendix G of the CEQA Guidelines as well as the BAAQMD CEQA Guidelines. The following discussion identifies the appropriate thresholds from these three documents. In general, implementing the project would have significant air quality impacts if it would: . Conflict with or obstruct implementation of the applicable air quality management plan; . Violate any air quality standard or contribute substantially to an existing or projected air quality violation; . Result in a cumulatively considerable net increase of any criteria pollutant for which the project region is nonattainment under an applicable federal or state ambient air quality standard (including releasing emissions that exceed quantitative thresholds for 03 precursors); . Expose sensitive receptors to substantial pollutant concentrations; or . Create objectionable odors affecting a substantial number of people. The BAAQMD CEQA Guidelines recommend analytical methodologies and provide evaluation criteria for determining the level of significance for project impacts under the above-listed general criteria. The BAAQMD's evaluation criteria for determining air quality impacts provide defined screening thresholds for pollutant emissions. Screening thresholds for air quality impacts from the BAAQMD CEQA Guidelines are presented below. Construction Emissions PMlO is the pollutant of greatest concern with respect to construction activities. Construction emissions of PMlO can vary greatly depending upon the level of activity, construction equipment, local soils and weather conditions, among other factors. As a result, the BAAQMD CEQA Guidelines specify that "[t]he District's approach to CEQA analyses of construction impacts is to emphasize implementation of effective and comprehensive control measures rather than detailed quantification of emissions." Therefore, the determination of significance with respect to construction emissions should be based on a consideration of the control measures to be implemented. If all the applicable control measures for PMlO indicated in the BAAQMD CEQA Guidelines would be Impact Sciences, Inc. 868-01 4.2-18 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality implemented, then air pollutant emissions from construction activities would be considered less than significant. If a project would not implement all applicable control measures, construction emissions may be considered a significant impact. Operational Emissions The BAAQMD CEQA Guidelines recommend that individual project impacts involving direct and/or indirect operational emissions that exceed the following thresholds be considered significant: · 80 pounds per day (ppd) of ROG · 80 ppd of NOx · 80 ppd of PMlO Direct emissions are those that are emitted on a site and include stationary sources and on-site mobile equipment, if applicable. Examples of land uses and activities that generate direct emissions are industrial operations and sources subject to an operating permit by the BAAQMD. Indirect emissions come from mobile sources that access the project site, but generally are emitted off site. For many types of land use development projects, the principal source of air pollutant emissions is the motor vehicle trips generated by the project. Local CO Concentrations Indirect CO emissions are considered significant if they will contribute to a violation of the state standards for CO (9.0 ppm averaged over 8 hours and 20 ppm over 1 hour). The BAAQMD recommends CO modeling for projects in which: (1) project vehicle emissions of CO would exceed 550 ppd; (2) project traffic would affect intersections or roadway segments operating at level of service (LOS) E or F, or would cause a decline to LOS E or F; or (3) project traffic would increase traffic volumes on nearby roadways by 10 percent or more (unless the increase in traffic volume is less than 100 vehicles per hour). If necessary, a simplified CO modeling analysis, described in the BAAQMD CEQA Guidelines, may be used to determine localized CO concentrations. If modeling demonstrates that the source would not cause a violation of the state standard at existing or reasonably foreseeable receptors, the automobile trips generated by Impact Sciences, Inc. 868-01 4.2 -19 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality 4.2.5.2 implementing the project would not have a significant impact on local air quality. Project Impacts Impact 4.2-1: Earthmoving and demolition activities during construction of the proposed project would generate criteria pollutant emissions. (S) During the construction phase of project site development, criteria pollutant emissions would be generated by on-site stationary sources, heavy-duty construction equipment, construction worker vehicles, energy use and heavy- duty trucks traveling to and from the site. In addition to construction vehicle and equipment emissions, fugitive dust would also be generated during demolition of the parking lot, grading and construction activities. Fugitive dust is generated when grading equipment breaks down surface materials. The resulting fugitive dust, which includes PMlO, is subsequently entrained into the air by wind and vehicle tires. Although much of this airborne dust would settle out on or near the project site, smaller particles would remain in the atmosphere, increasing existing particulate levels within the surrounding area. Sensitive receptors in proximity to the project site that could be affected by construction include the nearby daycare center and workers at adjacent businesses. Although construction-related emissions would be temporary in duration, without control measures the emissions could be substantial. Without the implementation of dust control measures, impacts related to construction emissions would be significant. Mitigation Measure 4.2-1: Construction Emissions The applicant shall require the construction contractor to implement a dust control program. The program shall address all construction activities involving grading, excavation, use of unpaved areas for staging, and extensive hauling of materials or building demolition. The dust control program shall include the following measures from Table 2 of the BAAQMD CEQA Guidelines as applicable and feasible: Impact Sciences, Inc. 868-01 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2-20 4.2 Air Quality Basic Control Measures (for all construction sites) . Water all active construction areas at least twice daily. . Cover all trucks hauling soil, sand and other loose materials or require all trucks to maintain at least 2 feet of freeboard. . Pave, apply water three times daily, or apply (non-toxic) soil stabilizers on all unpaved access roads, parking areas, and staging areas at construction sites. . Sweep daily (with water sweepers) all paved access roads, parking areas, and staging areas at construction sites. . Sweep streets daily (with water sweepers) if visible soil material is carried onto adjacent public streets. Enhanced Control Measures (for individual or combined construction sites larger than 4 acres) . Hydroseed or apply (non-toxic) soil stabilizers to inactive construction areas (previously graded areas inactive for 10 days or more). . Enclose, cover, water twice daily, or apply (non-toxic) soil binders to exposed stockpiles (dirt, sand, etc.). . Limit traffic speeds on unpaved roads to 15 miles per hour (mph). . Install sandbags or other erosion control measures to prevent silt runoff to public roadways. . Replant vegetation in disturbed areas as quickly as possible. In addition to the required Basic and Enhanced Control Measures, the BAAQMD strongly encourages the following optional measures at construction sites that are large in area, are located near sensitive receptors, or that for any other reason may warrant additional emissions reductions. As previously mentioned, a children's daycare facility is proposed directly across the street from the proposed project site. Should this facility be constructed and operational prior to the construction of the proposed project, the following dust control program should be implemented to minimize any potential impact to nearby sensitive receptors: . Install wheel washers for all exiting trucks or wash off the tires or tracks of all trucks and equipment prior to leaving the site. Impact Sciences, Inc. 868-01 4.2-21 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality . Install windbreaks or plant trees/vegetative windbreaks at the windward side(s) of construction areas. . Suspend excavation and grading activity when sustained winds exceed 25 mph. . Limit the area subject to excavation, grading and other construction activity at anyone time. Impact After Mitigation: Less than significant. Impact 4.2-2: Office/Research and Development envisioned by the project would generate criteria pollutant emissions from motor vehicles associated with worker's trips and area sources (e.g., natural gas combustion). (L TS) The proposed project would develop the site with two new office/research and development buildings, totaling 326,020 square feet. The project would provide parking for a total of 1,036 vehicles, including a three-level parking garage (all above ground). The garage would provide 898 parking spaces, while surface parking areas would provide parking for an additional 138 vehicles. Major landscape improvements would also be included. It is anticipated that occupancy of the site would occur by 2011, with full occupancy by 2015. Operational emissions associated with the development and occupancy of the project site would result primarily from vehicular trips to and from the office development. Other sources of emissions associated with implementing the project would include building and water heating equipment, landscaping equipment, consumer products, architectural coatings, and emissions from vehicular trips by the projected future workers. Predicted mobile source and area source emissions associated with project operation have been calculated using the land use and transportation computer model URBEMIS2002 (Version 8.7.0). URBEMIS2002 is distributed and approved for use by the CARB and recommended for quantification of construction and operational emissions by the BAAQMD. Operational emissions that would occur directly and indirectly from the proposed project are presented in Table 4.2-3, 2015 Estimated Operational Emissions. Impact Sciences, Inc. 868-01 4.2-22 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality Table 4.2-3 2015 Estimated Operational Emissions Summertime Emissions1 Operational (Mobile) Sources 15.68 23.40 Area Sources 4.82 2.18 Summertime Emission Totals 20.50 25.58 BAAQMD Thresholds 80 80 Exceeds Threshold? NO NO Wintertime Emissions2 Operational (Mobile) Sources 19.94 28.00 Area Sources 4.73 2.17 Wintertime Emission Totals 24.67 30.17 BAAQMD Thresholds 80 80 Exceeds Threshold? NO NO 180.78 2.46 183.24 0.22 0.00 0.22 211.07 1.83 212.90 0.22 0.00 0.22 37.74 0.01 37.75 80 NO 37.34 0.00 37.34 80 NO Source: Impact Sciences, Inc. Emissions calculations are provided in Appendix 4.2. Totals in table may not appear to add exactly due to rounding in the computer model calculations. 1 Summertime Emissions" are representative of the conditions that may occur during the ozone season (May 1 to October 31). 2 Wintertime Emissions" are representative of the conditions that may occur during the balance of the year (November 1 to April 30). As shown in Table 4.2-3, implementing the project would not generate daily direct and indirect emissions of ROG, NOx or PMlO that would exceed BAAQMD-recommended thresholds of significance. Therefore, operational emissions associated with the development envisioned by the project would be less than significant. Mitigation Measure: None required. Impact 4.2-3: Traffic generated by workers of the proposed project could contribute to carbon monoxide concentrations in excess of State and federal ambient air quality standards. (L TS) Motor vehicles are the primary source of pollutants within the project vicinity. Traffic-congested roadways and intersections have the potential to generate localized high levels of CO. Localized areas where ambient concentrations exceed state and/or federal standards are termed CO hotspots. There are no Impact Sciences, Inc. 868-01 4.2-23 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality notable stationary sources generating CO emissions in the local area; thus, local area CO emissions would result from vehicles traveling along local roadways. Carbon monoxide may occur as a localized exceedance of state and federal standards requiring additional analysis when a project is likely to subject sensitive receptors to high CO concentrations. BAAQMD CEQA Guidelines define sensitive receptors as those facilities that house or attract children, the elderly, or people with illnesses. Hospitals, schools, convalescent facilities, and residential areas are examples of sensitive receptors (BAAQMD 1999). This CO impact analysis evaluates 11 intersections located in the project study area for the presence of potential CO hotspots. Intersections that would operate at a Level of Service (LOS) of E or F or that would be degraded to a LOS of E or F due to the project's traffic were analyzed for the potential of CO hotspots. These intersections have been identified as those most adversely affected by traffic from the project site and include: Airport Blvd./U.S. 101 SB Hook Ramps Oyster Point/Dubuque Ave./U.S. 101 NB On-Ramp Oyster Point Blvd./Gateway/U.S. 101 SB Off-Ramp Flyover Oyster Point Blvd./Gull Ave. Airport Blvd./Grand Ave. E. Grand Ave./Forbes Blvd./Harbor Way Forbes Blvd./Allerton Ave. Airport Blvd./San Mateo Ave./Produce Ave. Gateway Blvd./South Airport Blvd./Mitchell Ave. Maximum CO concentrations for study intersections were calculated for peak- hour traffic volumes at each of these intersections using CALINE4, a dispersion model for predicting CO concentrations near roadways. For this analysis, CO concentrations were calculated based on a simplified CALINE4 screening model developed by the BAAQMD (BAAQMD 1999). The simplified model is intended as a screening analysis that identifies a potential CO hotspot. If a hotspot is identified, the complete CALINE4 model is then utilized to determine precisely Impact Sciences, Inc. 868-01 4.2-24 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality the CO concentrations predicted at the intersections in question. This methodology assumes worst-case conditions (i.e., wind direction is parallel to the primary roadway and 90 degrees to the secondary road, wind speed of less than 1 meter per second, and extreme atmospheric stability) and provides a screening of maximum, worst-case CO concentrations. Results of these calculations are presented below in Table 4.2-4, Carbon Monoxide Concentrations at Nearby Sensitive Receptors, for representative receptors located 0 and 25 feet from each roadway. As shown, the CALINE4 screening model predicts that, under worst-case conditions, CO concentrations would not exceed the state and federal I-hour and 8-hour CO standards near these intersections. Table 4.2-4 Carbon Monoxide Concentrations at Nearby Sensitive Receptors (parts per million) Airport Boulevard /U.S. 101 Southbound Hook Ramps 3.8 2.8 3.3 2.4 Oyster Point/Dubuque Ave./U.S. 101 Northbound On-Ramp 4.9 3.6 4.0 2.9 Oyster Point Blvd./Gateway/U.S. 101 SB Off- Ramp Flyover 4.4 3.2 3.8 2.8 Oyster Point Blvd./Gull Ave. 4.9 3.5 3.9 2.9 Airport Blvd./Grand Ave. 4.2 3.1 3.6 2.7 E. Grand Ave./Forbes Blvd./Harbor Way 5.1 3.7 4.1 3.0 E. Grand Ave./Allerton Ave. 4.0 2.9 3.4 2.5 Forbes Blvd./Allerton Ave. 3.4 2.5 3.1 2.3 Forbes Blvd./Gull Ave. 2.9 2.1 2.8 2.1 Airport Blvd./San Mateo Ave./Produce Ave. 4.7 3.4 3.9 2.9 Gateway Blvd./S. Airport Blvd./Mitchell Ave. 4.7 3.4 3.8 2.8 Source: Impact Sciences, Inc. Emissions calculations are provided in Appendix 4.2. State standard is 20 parts per million. Federal standard is 35 parts per million. State standard is 9.0 parts per million. Federal standard is 9 parts per million. Impact Sciences, Inc. 868-01 4.2-25 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality Mitigation Measure: None required. Impact 4.2-4: The project site may be located close to sources of toxic air contaminants that could expose sensitive receptors to toxic air contaminants in excess of acceptable levels. (L TS) As discussed previously, the BAAQMD recommends that impacts with respect to air toxics be evaluated based on the presence of buffer zones around existing or proposed land uses that would emit those air pollutants. As noted previously, there are no known sources within 1 mile of the project site. The project site would also be buffered from possible T AC sites by existing roadways, landscaped areas, and developed uses and would exceed the BAAQMD's suggested buffer distances. Given these reasons, no impacts to inhabitants of the project due to off-site sources of air toxics would result and the impacts from toxic air contaminants would be considered less than significant. Mitigation Measure: None required. 4.2.5.3 Cumulative Impacts According to the BAAQMD CEQA Guidelines, any project that would individually have a significant air quality impact would also have a significant cumulative air quality impact. As discussed previously, emissions associated with operation of the proposed project would not exceed the BAAQMD- recommended operational thresholds of significance. Therefore, the project would not individually have a significant air quality impact. For a project that does not individually have a significant air quality impact, the BAAQMD requires that a determination of cumulative impacts be based on an evaluation of the consistency of the project with the local general plan and of the general plan with the regional air quality plan. The latest u.s. EP A-approved regional air quality plan for this area is the 2000 CAP. If a project is proposed in a city or county with a general plan that is consistent with the CAP and the project is consistent with that general plan, the project would not have a significant cumulative impact. Impact Sciences, Inc. 868-01 4.2-26 494 Forbes Blvd. Office/R&D Project DEIR April 2007 4.2 Air Quality The South San Francisco General Plan does not conflict with or obstruct implementation of the 2000 CAP. Therefore, if the proposed project is consistent with the South San Francisco General Plan, it would not conflict or obstruct with implementation of the 2000 CAP. The CAP, discussed previously, was prepared to accommodate growth, reduce the pollutant levels in the Bay Area, meet federal and state ambient air quality standards, and minimize the fiscal impact that pollution control measures have on the local economy. The CAP assumed that future growth would occur within the zoning restrictions in effect at the time of its adoption. As discussed in Section 4.6, Land Use and Planning, the proposed project would be consistent with the existing zoning designation of the project site, as well as the projected cumulative future growth in the South San Francisco General Plan. Since the project is consistent with the South San Francisco General Plan, quantitative analysis is not required to determine whether the cumulative impact is significant, and the cumulative impacts associated with implementation of the applicable air quality plan are considered less than significant. Impact Sciences, Inc. 868-01 4.2-27 494 Forbes Blvd. Office/R&D Project DEIR April 2007