Air quality in California is regulated by the federal Clean Air Act (CAA), the California Clean Air Act (CCAA), and local regulations. Under the CAA, the U.S. Environmental Protection Agency establishes primary and secondary national ambient air quality standards (NAAQs) for six criteria pollutants: ozone, nitrogen oxide, sulfur oxide, and carbon monoxide, lead, and particulate matter. (42 U.S.C. §§ 7408-7409; 40 C.F.R. §§ 50.1-50.19.) The CAA requires states to adopt state implementation plans (SIPs) to attain NAAQs. (42 U.S.C. § 7410.) The California Air Resources Board (CARB) is responsible for meeting the state requirements of the CAA, administering the CCAA, and establishing state-specific California Ambient Air Quality Standards (CAAQS), which are as (or more) stringent than their federal counterparts. (See Cal. Health & Saf. Code § 39606.) At the local level, the state’s thirty-five Air Quality Management Districts (AQMDs) monitor air quality, enforce state and federal regulations, and implement programs to meet ambient air quality standards. Additionally, some counties and cities have adopted plans and ordinances – usually concerning odors and dust – which further regulate local air quality.
In accordance with the state’s history of aggressive air quality monitoring and emissions restrictions, the Legislature stated in CEQA’s opening preamble that it is the policy of the state to take all actions necessary to provide Californians with clean air. (Pub. Resources Code, § 21001(b).) CEQA requires lead agencies to evaluate whether a project will conflict with an applicable air quality plan, cause a cumulatively considerable net increase in any criteria pollutant for which the region is in non-attainment, expose sensitive receptors to substantial pollutant concentrations, or result in other emissions – including odors – adversely affecting a substantial number of people. (See CEQA Guidelines, Appendix G, § III.) These requirements are described in more detail in the following sections. CEQA also requires evaluation of a project’s greenhouse gas emissions and vehicle miles traveled (VMT). For more information on greenhouse gas and VMT analyses, please refer to our blog’s Greenhouse Gas and VMT category overviews.
Standard of Review
When an EIR’s air quality analysis is challenged, courts independently review whether the lead agency complied with CEQA’s statutory requirements but apply the deferential substantial evidence standard to the agency’s factual determinations. (See Sierra Club v. County of Fresno (2018) 6 Cal.5th 502, 512 (Friant Ranch).) Accordingly, methodological decisions, such as those related to thresholds of significance and which analytical model to employ, need only be supported by substantial evidence. (See, e.g., Mission Bay Alliance v. Office of Community Investment & Infrastructure (2016) 6 Cal. App. 5th 160, 206 (Mission Bay Alliance); Gray v. County of Madera (2008) 167 Cal.App.4th 1099, 1126; Rialto Citizens for Responsible Growth v. City of Rialto (2012) 208 Cal.App.4th 899, 933.) However, courts have not granted agencies deference where the courts find the air quality analysis is inadequate and fails to provide a good faith disclosure of a project’s potential impacts. (See Friant Ranch, supra, 6 Cal.5th at pp. 516, 519-522; City of Long Beach v. City of Los Angeles (2018) 19 Cal.App.5th 465, 484-488 (City of Long Beach).)
Air Quality Plans
Lead agencies must determine whether a project will conflict with or obstruct the implementation of any applicable air quality plan, including whether the project will implement applicable control and implementation measures. (See, e.g., Spring Valley Lake Assn. v. City of Victorville (2016) 248 Cal.App.4th 91, 108 [revised air quality consistency analysis lacked evidence to support a finding of consistency with specific implementation measures].) Typically, the applicable air quality plans are those prepared by the local AQMD and include attainment plans where the region is in “nonattainment” (i.e., when it has been identified as failing to meet the air quality standards of the CAA or CCAA). Lead agencies may also evaluate consistency with plans that are not strictly air quality plans, such as a Regional Transportation Plan/Sustainable Communities Plan and/or General Plan goals and policies.
Lead agencies must consider a proposed project’s criteria pollutant emissions and whether a project in a nonattainment region results in a cumulatively considerable net increase of any criteria pollutant. CEQA Guidelines, Appendix G (III)(c); see, e.g., Kings County Farm Bureau v. City of Hanford (1990) 221 Cal. App. 3d 692, 713, 717-721 (Kings County) [EIR for a project in a nonattainment region for ozone and PM10 contained a misleading and inadequate discussion of the project’s contributions to cumulatively considerable increases in those pollutants].) In addition to analyzing whether a project will emit significant quantities of criteria pollutants, recent case law has held that EIRs must correlate these increases to specific impacts on human health. (See Friant Ranch, supra, 6 Cal.5th at pp. 519-522; Bakersfield Citizens for Local Control v. City of Bakersfield (2004) 124 Cal.App.4th 1184, 1219-1220 (Bakersfield Citizens); but see Beverly Hills Unified School Dist. v. Los Angeles County Metropolitan Transportation Authority (2015) 241 Cal.App.4th 627, 666-668.) For example, in Friant Ranch, the California Supreme Court, applying the de novo standard of review, held that the EIR for a master-planned retirement community failed to adequately discuss criteria pollutant impacts, even though it outlined some of the symptoms associated with exposure to those pollutants. (See Friant Rach, supra, 6 Cal.5th at pp. 519-522.) The Friant Ranch EIR erred by failing to communicate the connection between the raw data estimating the project’s criteria pollutant emissions and the resultant health effects. (Ibid.) Agencies must make a reasonable effort to contextualize significant air quality impacts, or explain why an analysis connecting those impacts to human health consequences would be infeasible. (Ibid.)
Toxic Air Contaminants and Sensitive Receptors
Toxic air contaminants (TACs) are airborne pollutants that may cause or contribute to an increase in mortality or serious illness. (Health & Saf. Code, § 39655(a).) TACs create localized impacts, and the risks they pose dissipate with distance. Recognizing that these pollutants may have a disproportionate impact close to a project site, CEQA requires analysis of impacts on nearby sensitive receptors. Sensitive receptor locations may include, but are not limited to, hospitals, schools, and day care centers. (Cal. Health & Saf. Code § 42705.5(a)(5).) CEQA analyses frequently include nearby residents as sensitive receptors as well.
Lead agencies must make a reasonable effort to analyze and disclose the type and amount of TACs a project is likely to emit, as well as the resultant health effects, so decision makers and the public may make an informed decision on project approval. (See Berkeley Keep Jets Over the Bay Commission v. Board of Port Cmrs. (2001) 91 Cal.App.4th 1344, 1367-1371.) Unlike criteria pollutants, TACs are not subject to ambient air concentration limits. (Mission Bay Alliance, supra, 6 Cal. App. 5th at p. 203.) Instead, they are regulated using a risk-based approach. (Ibid.) While not required under CEQA, Health Risk Assessments (HRAs) – which contain a comprehensive quantitative analysis of TAC dispersal and the potentiality for exposing receptors to TACs – are a tool agencies use to analyze the health risks a project poses to sensitive receptors. (See, e.g., id. at pp. 203-204; East Sacramento Partnerships for a Livable City v. City of Sacramento (2016) 5 Cal.App.5th 281, 288 (East Sacramento Partnerships).) Local AQMDs provide technical guidance on the procedures to implement when preparing an HRA, and often recommend considering inhalation rates among applicable sensitive receptors, the frequency and duration of exposure, cancer and other disease risk calculations, and adjustments based on receptors’ age and health status. (See, e.g., BAAQMD Air Toxic NSR Program Health Risk Assessment Guidelines; SCAQMD Risk Assessment Procedures for Rules 1401 and 212; SDAPCD Supplemental Guidelines for Submission of Rule 1200 Health Risk Assessments.)
Lead agencies must also consider offensive odors, which, while rarely causing any physical harm, can lead to discomfort and community annoyance. Considering the impact of an odor is an inherently subjective exercise. The occurrence and severity of odor impacts depend on the nature, frequency, an intensity of the source; wind speed and direction; and the sensitivity of receptors. Odor mitigation usually involves increasing the distance between receptors and the odor source or implementing air filtration systems to reduce the spread of odors.
Lead agencies must make a “good faith and reasonable disclosure” of a project’s incremental cumulatively considerable air quality impacts, taking past, present, and probable future projects causing similar impacts into account. (CEQA Guidelines, §15130(a)-(b); City of Long Beach, supra, 19 Cal.App.5th at p. 488-490.) While projects must analyze the cumulative impacts they may have on the population, they need not analyze the impacts of existing environmental issues – see our discussion regarding “Reverse CEQA” below for more information.
In undertaking a cumulative air quality analysis, the lead agency must analyze the cumulative impacts of the project and other sources on air quality. (See Kings County, supra, 221 Cal.App.3d at pp. 720-721.) It cannot avoid this analysis by finding the project itself would have a relatively minor contribution to the overall problem. (Ibid.) Additionally, given air quality impacts are often inherently cumulative, courts are willing to scrutinize the lead agency’s determination regarding the geographic scope for the air quality analysis. (See Bakersfield Citizens, supra, 124 Cal.App.4th at pp. 1216-1218 [finding EIRs for two shopping centers with overlapping “market areas” were legally inadequate because the cumulative impacts analyses of each project excluded the other project]; Kings County, supra, 221 Cal.App.3d at pp. 723-724 [EIR found inadequate where it did not analyze impacts across an entire air basin and the record did not include sufficient information to determine if this resulted in an underestimation of the severity of the impact]; but see City of Long Beach v. Los Angeles Unified School Dist. (2009) 176 Cal.App.4th 889, 907-908 [geographic scope for cumulative analysis upheld].) Finally, omitting “meaningful information” regarding cumulative impacts can render an EIR inadequate. (See City of Long Beach, supra, 19 Cal.App.5th at p. 488-490 [failure to discuss expansion of adjacent railyard operations rendered analysis inadequate].)
An adequate air quality analysis must be thorough, but generally does not require consideration of existing environmental conditions on project users. (See California Building Industry Association v. Bay Area Quality Management District (2015) 62 Cal.4th 369, 388 (California Building); South Orange County Wastewater Authority v. City of Dana Point (2011) 196 Cal.App.4th 1604, 1614-1615 (South Orange County).) For example, in South Orange County, petitioners unsuccessfully alleged that an EIR was required to analyze the impact that odors from an existing sewage treatment plant would have on the proposed project, which would be located adjacent to treatment plant. And, in California Building, the California Supreme Court held that the Bay Area Air Quality Management District could not require all new projects to conduct an analysis of existing air pollution sources on future residents or users. (California Building, supra, 62 Cal.4th at pp. 391-392.) California Building clarified that CEQA “generally does not require an analysis of how existing environmental conditions will impact a project’s future users or residents,” though it recognized limited exceptions to this rule exist for certain airport, school, and housing projects. (Id. at pp. 386, 391; see also East Sacramento Partnerships, supra, 5 Cal.App.5th at pp. 295-296 [fact project site is exposed to TACs, including potential off-site methane migration, is not a CEQA impact].)
California Building further explained that when a proposed project risks exacerbating existing conditions, an agency must analyze the potential impact of such hazards on future users. (See id. at 389.) “In those specific instances, it is the project’s impact on the environment – and not the environment’s impact on the project – that compels an evaluation of how future residents or users could be affected by exacerbated conditions.” (Id. at pp. 377-378 (original emphasis).) However, to present a cognizable claim under the exacerbation standard, petitioners must produce substantial evidence that a project will produce a particular adverse effect – merely raising unsubstantiated concerns that a project will exacerbate air pollution do not suffice. (East Sacramento Partnerships, supra, 5 Cal.App.5th at pp. 296-297.)
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