Filed 8/12/16
                           CERTIFIED FOR PUBLICATION

                IN THE COURT OF APPEAL OF THE STATE OF CALIFORNIA

                             FIRST APPELLATE DISTRICT

                                      DIVISION FIVE


CALIFORNIA BUILDING INDUSTRY
ASSOCIATION,
        Plaintiff and Respondent,                   A135335 & A136212

v.                                                  (Alameda County
BAY AREA AIR QUALITY                                Super. Ct. No. RG10548693)
MANAGEMENT DISTRICT,
        Defendant and Appellant.


        The California Environmental Quality Act (CEQA; Pub. Res. Code, § 21000
et seq.) requires public agencies to conduct an environmental review of discretionary
projects they carry out or approve and to prepare an environmental impact report (EIR)
for any project that may have a significant effect on the environment. (Pub. Res. Code,
§§ 21151, 21100, 21080, 21082.2.) The CEQA Guidelines1 encourage public agencies to
develop and publish “thresholds of significance” to assist in determining whether a
project’s effect will be deemed significant. (CEQA Guidelines, § 15064.7.) “A threshold
of significance is an identifiable quantitative, qualitative or performance level of a
particular environmental effect, non-compliance with which mean the effect will
normally be determined to be significant by the agency and compliance with which
means the effect normally will be determined to be less than significant.” (Id., subd. (a).)

1
      References to the CEQA Guidelines are to the regulations for the implementation
of CEQA codified in Title 14, section 15000 et seq. of the California Code of
Regulations, which have been developed by the Office of Planning and Research and
adopted by the Secretary of the California Natural Resources Agency. (Pub. Res. Code, §
21083.)
                                              1
       Following a grant of review of our previous opinion in this case, the Supreme
Court held CEQA “does not generally require an agency to consider the effects of
existing environmental conditions on a proposed project’s future users or residents.”
(California Building Industry Assn. v. Bay Area Air Quality Management District (2015)
62 Cal.4th 369, 392 (Building Association).) It remanded the case to this court to
consider whether thresholds of significance adopted by appellant Bay Area Air Quality
Management District (District) ran afoul of this principle and the extent to which
respondent California Building Industry Association (CBIA) was entitled to relief. (Id. at
pp. 392–393.) We conclude the challenged thresholds are not invalid on their face, but
may not be used for the primary purpose envisioned by District, namely, to routinely
assess the effect of existing environmental conditions on future users or occupants of a
project.
                                   I. BACKGROUND
       A. The Thresholds and District Guidelines
       District is a regional agency charged with limiting nonvehicular air pollution in the
San Francisco Bay Area. It is authorized to adopt and enforce rules and regulations
regarding the emission of pollutants, and to ensure state and federal ambient air quality
standards are met. (Health & Saf. Code, §§ 39002, 40000, 40001, subd. (a), 40200.)
Among its other activities, District monitors air quality, engages in public outreach
campaigns, issues permits to certain emitters of air pollution, and promulgates rules to
control emissions. (Health & Saf. Code, §§ 42300, 42301.5, 42315.)
       In 1999, District published thresholds of significance concerning certain air
pollutants, along with guidelines concerning their use and the analysis of air quality
issues, in general, under CEQA. District’s 1999 thresholds and guidelines were intended
to serve as a guide for those who prepare or evaluate air quality impact analyses for
projects and plans in the San Francisco Bay Area, and set forth the levels at which toxic
air contaminants (TACs) and certain types of particulate matter would be deemed
environmentally significant.


                                             2
           In 2009, District drafted new proposed thresholds of significance, partly in
response to the Legislature’s adoption of laws addressing greenhouse gases (GHGs). It
cited three factors justifying the new thresholds: (1) the enactment of more stringent state
and federal air quality standards since the adoption of the earlier thresholds and the
addition of PM2.5 (particulate matter with a diameter of 2.5 microns or less) to the
substances regulated; (2) the discovery that TACs present an even greater health risk than
previously thought; and (3) the growing concern with global climate change.
           A number of organizations, businesses, and local governments participated in
public hearings, meetings, and workshops held by District regarding the proposed
revisions. One participant was CBIA, a statewide trade organization representing
members involved in residential and light commercial construction, including
homebuilders, architects, trade contractors, engineers, designers, and other building
industry professionals. During the public hearing process, CBIA and other groups
expressed concern the proposed thresholds and guidelines were too stringent and would
make it difficult to complete urban infill projects close to existing sources of air
pollution. According to these groups, EIRs would be required for many projects where
they otherwise would not have been, and other projects would not be approved. If these
infill projects were not feasible, they argued, developers would build in more suburban
areas, thus (paradoxically) causing even more pollution due to automobile commuter
traffic.
           On June 2, 2010, District’s board of directors passed resolution No. 2010-06
(Resolution), adopting new thresholds of significance for air pollutants, including GHGs,
TACs and PM2.5 (the Thresholds). As set forth in the Resolution, the Thresholds “reflect
the levels at which environmental effects should be considered ‘significant’ for purposes
of CEQA, such that exceedance of the [T]hresholds will normally establish that the effect
is ‘significant’ under CEQA and compliance with the [T]hresholds normally will
establish that the effect is less than ‘significant’ under CEQA[.]”
           The Thresholds, which were attached as Exhibit A to the Resolution, set
“construction-related” and “operational-related” significance levels for TACs and PM2.5

                                                 3
emissions, broken down into four separate categories: (1) “Risks and Hazards—New
Source (Individual Project);” (2) “Risks and Hazards—New Receptor (Individual
Project);” (3) “Risks and Hazards—New Source (Cumulative Thresholds);” and (4)
“Risks and Hazards—New Receptor (Cumulative Thresholds).” Relevant to this case are
the significance levels applicable to a new receptor (Receptor Thresholds), as to which
the Resolution states, “[I]t is the policy of the [District] that Lead agencies in the Bay
Area apply the CEQA Thresholds of Significance for the Risk and Hazard thresholds for
Receptor Projects for Notices of Preparation issued, and environmental analyses begun,
after January 1, 2011.”2
       Also in 2010, District published new “CEQA Air Quality Guidelines” (District
Guidelines), which include the Thresholds and suggest methods of assessing and
mitigating impacts found to be significant. The self-stated purpose of these District
Guidelines “is to assist lead agencies in evaluating air quality impacts of projects and
plans proposed in the San Francisco Bay Area Air Basin (SFBAAB). The [District]
Guidelines provide[] [District]-recommended procedures for evaluating potential air
quality impacts during the environmental review process consistent with CEQA
requirements. . . . [¶] Land development plans and projects have the potential to generate
harmful air pollutants that degrade air quality and increase local exposure. The [District]
Guidelines contain instructions on how to evaluate, measure, and mitigate air quality
impacts generated from land development construction and operation activities. The
[District] Guidelines focus on criteria air pollutant, greenhouse gas (GHG), toxic air

2
       The Receptor Thresholds set significance levels for the future occupants of a
project if, within a 1,000-foot zone of influence: (1) the targeted emissions exceed
compliance with a qualified community risk reduction plan; (2) the cumulative emissions
from all sources of specified pollutants expose those occupants to an increased cancer
risk greater than 100 in a million, or the emissions from a single source expose those
occupants to an increased cancer risk greater than 10 in a million; or (3) there is an
incremental annual average increase of more than 0.3 microgram of PM2.5 per cubic
meter from a single source or 0.8 microgram per cubic meter from all sources. The same
measures of significance were set for new sources of emissions (the Source Thresholds,
which are not challenged by CBIA).

                                              4
contaminant, and odor emissions generated from plans or projects. [¶] The [District]
Guidelines are intended to help lead agencies navigate the CEQA process. The [District]
Guidelines offer step-by-step procedures for a thorough environmental analysis of
adverse air emissions due to land development in the Bay Area.” (District Guidelines,
[¶] 1.1.)
        Paragraph 5.2 of the District Guidelines directs the lead agency to “determine
whether operational-related TAC and PM2.5 emissions generated as part of a proposed
project siting a new source or receptor would expose existing or new receptors to levels
that exceed [the District’s] applicable Thresholds of Significance . . . .” Paragraph 5.2.5
of the District Guidelines, entitled “Siting a New Receptor,” states: “If a project is likely
to be a place where people live, play, or convalesce, it should be considered a receptor. It
should also be considered a receptor if sensitive individuals are likely to spend a
significant amount of time there. . . . Examples of receptors include residences, schools
and school yards, parks and play grounds, daycare centers, nursing homes, and medical
facilities. . . . [¶] When siting a new receptor, a Lead Agency shall examine existing or
future proposed sources of TAC and/or PM2.5 emissions that would adversely affect
individuals within the planned project. A Lead Agency shall examine: [¶] • the extent to
which existing sources would increase risk levels, hazard index, and/or PM2.5
concentrations near the planned receptor, [¶] • whether the existing sources are permitted
or non-permitted by [the District], and [¶] • whether there are freeways or major
roadways near the planned receptor. [¶] [The District] recommends that a Lead Agency
identify all TAC and PM2.5 sources located within a 1,000 foot radius of the proposed
project site . . . .”
        B. CBIA’s Petition for Writ of Mandate and Complaint for Declaratory Relief
        On November 29, 2010, CBIA filed a petition for writ of mandate and complaint
for declaratory relief challenging the Thresholds. (Code Civ. Proc., §§ 1060, 1085; Pub.
Res. Code, § 21168.5.) The trial court conducted a hearing on the merits of the following
claims: (1) District should have conducted a CEQA review of the Thresholds before their
promulgation because they constitute a “project” within the meaning of CEQA; (2) the
                                              5
Receptor Thresholds were arbitrary and capricious to the extent they required an
evaluation (impermissible under CEQA) of the impacts the environment would have on a
given project; (3) aspects of the Thresholds were not based on substantial evidence; and
(4) the Thresholds failed the “rational basis” test because sufficient evidence did not exist
for their approval. Following a hearing, the court agreed District should have conducted
an environmental review under CEQA before issuing the Thresholds and issued a writ of
mandate directing District to set aside its approval of the Thresholds. The court awarded
CBIA attorney fees under Code of Civil Procedure section 1021.5.
       C. District’s Appeal
       District appealed the order granting the writ and the award of attorney fees,
arguing the Thresholds were not a project requiring a CEQA review prior to their
promulgation. We agreed and reversed the order granting the writ. We also rejected
CBIA’s defensive challenges to the sufficiency of the evidence supporting the
Thresholds, as well as CBIA’s argument that the Receptor Thresholds should be set aside
because the purpose of CEQA was to protect the environment from proposed projects,
not to protect the future occupants or users of proposed projects from the environment.
(See Ballona Wetlands Land Trust v. City of Los Angeles (2011) 201 Cal.App.4th 455,
473; South Orange County Wastewater Authority v. City of Dana Point (2011) 196
Cal.App.4th 1604, 1612–1616; City of Long Beach v. Los Angeles Unified School Dist.
(2009) 176 Cal.App.4th 889, 905; Baird v. County of Contra Costa (1995) 32
Cal.App.4th 1464, 1468.)
       With respect to this last issue, we declined to resolve whether, as a general rule, an
EIR may be required solely because an existing project may adversely affect future users
or occupants of a project. We found the issue was better reserved for a case in which the
Receptor Thresholds had actually been applied to a project, and concluded the Receptor
Thresholds were not invalid on their face because there were circumstances in which they
could be utilized even if, as a general rule, CEQA did not require an analysis of the effect
the existing environment would have upon future occupants or users. We also reversed
the trial court’s award of attorney fees, finding CBIA was no longer a successful party

                                              6
under Code of Civil Procedure section 1021.5. (Building Association, supra, 62 Cal.4th
at p. 393.)
       D. Supreme Court Decision on Grant of Review
       CBIA filed a petition for review on the following issues: (1) whether CEQA
requires an analysis of the impacts of the existing environment upon a project; (2)
whether CEQA established a “blanket exemption” from environmental review for an
agency’s adoption of a rule, regulation or ordinance of general application adopted as a
threshold of significance; and (3) whether CEQA applied a heightened evidentiary
burden to the question of whether an activity is a project when the potential
environmental change involves displaced development. The Supreme Court granted the
petition in part, limiting the scope of review to the question: “Under what circumstances,
if any, does CEQA require an analysis of how existing environmental conditions will
impact future residents or users (receptors) of a proposed project?” (Building
Association, supra, 62 Cal.4th at p. 381.)
       In the proceedings before the Supreme Court on review, District took the position
that “when existing environmental conditions on or near the proposed project site pose
hazards to humans brought to the site by the project, the project may have potentially
significant environmental effects requiring evaluation.” (Building Association, supra, 62
Cal.4th at p. 386.) CBIA took the “contrasting view” that the relevant consideration
when determining the need for an EIR was the project’s effect on the environment, not
the environment’s effect on the project. (Ibid.) In its opinion, the Supreme Court agreed
with CBIA as a general matter: “In light of CEQA’s text and structure, we conclude that
CEQA generally does not require an analysis of how existing environmental conditions
will impact a project’s future users or residents.” (Building Association, supra, 62
Cal.4th at p. 386.)
       In reaching this conclusion, the Supreme Court acknowledged District’s argument
that CEQA is concerned with public health and safety, and requires a finding of “ ‘ “a
significant effect on the environment” ’ ([Pub. Res. Code,] § 21083(b)) whenever the
‘environmental effects of a project will cause substantial adverse effects on human

                                             7
beings, either directly or indirectly.’ ([Pub. Res. Code], § 21083(b)(3).)” (Building
Association, supra, 62 Cal.4th at p. 387.) But the District’s reading of this language
“goes too far. . . . The statute does not provide enough of a basis to suggest that the term
‘environmental effects’ as used in this context is meant, as a general matter, to encompass
these broader considerations associated with the health and safety of a project’s future
residents or users. [Public Resources Code s]ection 21060.5 defines ‘environment’ as
‘the physical conditions which exist within the area which will be affected by a proposed
project, including land, air, water, minerals, flora, fauna, noise, objects of historic or
aesthetic significance.’ ([Pub. Res. Code,] § 21060.5.) Given the text of [Public
Resources Code] section 21083 and other relevant provisions of the statutory scheme to
which it belongs—including CEQA’s statute-wide definition of ‘environment’—the
phrase in question is best interpreted as limited to those impacts on a project’s users or
residents that arise from the project’s effects on the environment. Even if one reads into
CEQA’s definition of ‘environment’ a concern with people—a reading that,
notwithstanding [Public Resources Code] section 21060.5, is conceivable given the
Legislature’s interest in public health and safety—[Public Resources Code] section 21083
does not contain language directing agencies to analyze the environment’s effects on a
project. Requiring such an evaluation in all circumstances would impermissibly expand
the scope of CEQA.” (Building Association, at p. 387, italics added.)
       The Supreme Court continued: “The rest of the statute’s relevant provisions
underscore why. Despite the statute’s evident concern with protecting the environment
and human health, its relevant provisions are best read to focus almost entirely on how
projects affect the environment. (E.g., [Pub. Res. Code,] §§ 21060.5 [defining
environment], 21068 [‘ “Significant effect on the environment” means a substantial, or
potentially substantial, adverse change in the environment’], 21083(b)(1) [directing that a
project shall be found to have a ‘ “significant effect on the environment” ’ if it ‘has the
potential to degrade the quality of the environment’].) Indeed, the key phrase ‘significant
effect on the environment’ is explicitly defined by statute in a manner that does not
encompass the environment’s effect on the project. (§ 21068 [‘ “Significant effect on the

                                               8
environment” means a substantial, or potentially substantial, adverse change in the
environment.’].) And nowhere in the statute is there any provision that cuts against the
specificity of that definition by plainly delegating power for the agency to determine
whether a project must be screened on the basis of how the environment affects its
residents or users.” (Building Association, supra, 62 Cal.4th at p. 387.)
       The court then turned its attention to CEQA Guidelines section 15126.2(a), cited
by District in support of its position that CEQA requires a consideration of the
environment’s effect upon future users of a project. CEQA Guidelines section
15126.2(a) “calls for an EIR to ‘identify and focus on the significant environmental
effects of the proposed project,’ including ‘any significant environmental effects the
project might cause by bringing development and people into the area affected.’ (Italics
added.)” (Building Association, supra, 62 Cal.4th at p. 385.) It further states: “[A]n EIR
[should] evaluate any potentially significant impacts of locating development in other
areas susceptible to hazardous conditions (e.g., floodplains, coastlines, wildfire risk
areas) as identified in authoritative hazard maps, risk assessments or in land use plans
addressing such hazards areas.’ ” (CEQA Guidelines, § 15126(a).)
       The Supreme Court found valid the above-quoted portions of CEQA Guidelines
section 15126(a) “to the extent they call for evaluating a project’s potentially significant
exacerbating effects on existing environmental hazards . . . . ” (Building Association,
supra, 62 Cal.4th at p. 388.) “Because this type of inquiry still focuses on the project’s
impacts on the environment—how a project might worsen existing conditions—directing
an agency to evaluate how such worsened conditions could affect a project’s future users
or residents is entirely consistent with this focus and with CEQA as a whole.” (Id. at p.
389.) But the Court found two additional sentences contained in CEQA Guidelines
section 15126.2(a) to be “clearly erroneous and unauthorized under CEQA: ‘[A]n EIR
on a subdivision astride an active fault line should identify as a significant effect the
seismic hazard to future occupants of the subdivision. The subdivision would have the
effect of attracting people to the location and exposing them to the hazards found there.’ ”
(Building Association, supra, 62 Cal.4th at p. 390.) These two sentences—which

                                              9
described a project that would not itself exacerbate the hazard, but whose occupants
might be jeopardized by existing conditions—“impos[ed] a requirement too far removed
from evaluating a project’s impacts on the environment.” (Ibid.)
       The Supreme Court recognized statutory exceptions to the general rule that CEQA
does not require an analysis of the environment’s effects upon a project. “Although
CEQA does not generally require an evaluation of the effects of existing hazards on
future users of the proposed project, it calls for such an analysis in several specific
contexts involving certain airport (§ 21096) and school construction projects (§ 21151.8),
and some housing development projects (§§ 21159.21, subds. (f), (h), 21159.22, subds.
(a), (b)(3), 21159.23, subd. (a)(2)(A), 21159.24, subd. (a)(1), (3), 21155.1, subd. (a)(4),
(6)).” (Building Association, supra, 62 Cal.4th at p. 391.) These provisions “constitute
specific exceptions to CEQA’s general rule requiring consideration only of a project’s
effect on the environment, not the environment’s effects on project users. Accordingly,
we cannot, as the District urges, extrapolate from these statutes an overarching, general
requirement that an agency analyze existing environmental conditions whenever they
pose a risk to the future residents or users of a project.” (Id. at p. 392.)
       Having clarified that CEQA “does not generally require an agency to consider the
effects of existing environmental conditions on a proposed project’s future users or
residents” but does mandate “an analysis of how a project might exacerbate existing
environmental hazards” (Building Association, supra, 62 Cal.4th at p. 392), the Supreme
Court remanded the case to us to “address certain potentially important arguments for and
against [CBIA’s petition for writ relief] in light of CEQA’s requirements . . . .” as it had
interpreted them. (Id. at pp. 392–393.) We now consider the validity of the Receptor
Thresholds in light of the Supreme Court’s decision in Building Association, and the
relief, if any, to which CBIA is entitled with respect to those thresholds.
                                      II. DISCUSSION
       A. CEQA Review and Thresholds of Significance—General Principles
       “ ‘CEQA embodies our state’s policy that “the long-term protection of the
environment . . . shall be the guiding criterion in public decisions.” ’ [Citations.] To

                                              10
implement this policy, CEQA and the Guidelines issued by the State Resources Agency
have established a three-tiered process. [Citation.] In the first step, an agency conducts a
preliminary review to determine whether CEQA applies to a proposed activity.
[Citation.] If the project is exempt from CEQA, either because it is not a ‘project’ as
defined in section 15378 of the Guidelines or because it falls within one of several
exemptions to CEQA, ‘no further environmental review is necessary. The agency may
prepare and file a notice of exemption, citing the relevant section of the Guidelines and
including a brief ‘statement of reasons to support the finding.’ [Citation.] If, however,
the project does not fall within any exemption, the agency must proceed with the second
tier and conduct an initial study. [Citation.] If the initial study reveals that the project
will not have a significant environmental effect, the agency must prepare a negative
declaration, briefly describing the reasons supporting the determination. [Citations.]
Otherwise, the third step in the process is to prepare a full environmental impact report
(EIR) on the proposed project.’ ” (San Francisco Beautiful v. City and County of San
Francisco (2014) 226 Cal.App.4th 1012, 1019–1020.)
       Under CEQA Guidelines section 15064.7, “(a) Each public agency is encouraged
to develop and publish thresholds of significance that the agency uses in the
determination of the significance of environmental effects. A threshold of significance is
an identifiable quantitative, qualitative or performance level of a particular environmental
effect, non-compliance with which means the effect will normally be determined to be
significant by the agency and compliance with which means the effect normally will be
determined to be less than significant. [¶] (b) Thresholds of significance to be adopted
for general use as part of the lead agency’s environmental review process must be
adopted by ordinance, resolution, rule, or regulation, and developed through a public
review process and be supported by substantial evidence.” Such thresholds may be
employed at various stages of CEQA review, but are not determinative and “cannot be
applied in a way that would foreclose the consideration of other substantial evidence
tending to show the environmental effect to which the threshold relates might be


                                              11
significant.” (Protect the Historic Amador Waterways v. Amador Water Agency (2004)
116 Cal.App.4th 1099, 1109.)
       B. Standard of Review
       “Any statute, local ordinance or regulation that conflicts with state law is invalid
and preempted.” (Mountains Recreation Conservation Authority v. Kaufman (2011) 198
Cal.App.4th Supp. 1, 5.) CBIA argues the Receptor Thresholds are invalid because they
require agencies to consider the effect of existing environmental conditions upon future
users and occupants of proposed projects, contrary to the Supreme Court’s holding in
Building Association that “CEQA does not require an agency to consider the impact of
existing conditions on future project users” except for certain airport, school and housing
development projects. (Building Association, supra, 62 Cal.4th at p. 378.) Questions
concerning the interpretation or application of CEQA, and the consistency of local
regulations with CEQA, are matters of law subject to de novo or independent review.
(Concerned Dublin Citizens v. City of Dublin (2013) 214 Cal.App.4th 1301, 1311; San
Lorenzo Valley Community Advocates for Responsible Education v. San Lorenzo Valley
Unified School Dist. (2006) 139 Cal.App.4th 1356, 1375; Communities for a Better
Environment v. California Resources Agency (2002) 103 Cal.App.4th 98, 109–110
(CBE), disapproved on another ground in Berkeley Hillside Preservation v. City of
Berkeley (2015) 60 Cal.4th 1086, 1109, fn. 3; see PaintCare v. Mortensen (2015) 233
Cal.App.4th 1292, 1305.).
       C. A Lead Agency Cannot Require an EIR or Mitigation Measures Based Solely
       on a Determination a Project Will Have a Significant Effect Upon a New Receptor
       District acknowledges in its brief on remand that the Receptor Thresholds
“provide public agencies with a standard by which to determine whether future project
residents or users will be exposed to an unacceptable health risk because the project will
be located near a source of toxic air pollution.” As the Supreme Court made clear in
Building Association, CEQA does not generally require an agency to consider the effects
of existing environmental conditions on a proposed project’s future users or occupants.
(Building Association, supra, 62 Cal.4th at p. 392.) Consistent with Building

                                             12
Association, a lead agency could not require the preparation of an EIR, other CEQA
review, or the implementation of mitigation measures for a proposed project solely
because the emissions in the existing environment meet the criteria of the Receptor
Thresholds as to future users or occupants of the project.
       D. The Receptor Thresholds Have Valid Applications Under Certain
       Circumstances
       District argues that although “the mere exposure of people to existing hazards
[does] not cause an environmental effect requiring analysis under CEQA,” the Receptor
Thresholds need not be set aside because there are legitimate circumstances in which they
could be utilized during the CEQA process. We consider each in turn.
               1. Voluntary Use of Receptor Thresholds by an Agency
       District contends that while CEQA does not generally require an evaluation of
existing conditions upon future occupants or users of a proposed project, a public agency
retains the discretion to make such an evaluation when conducting an analysis of its own
project. It argues that in such cases, the Receptor Thresholds provide an appropriate
measure of existing air pollution. We agree.
       In Building Association, supra, 62 Cal.4th at page 388, the Supreme Court
explained that CEQA “does not proscribe consideration of existing conditions” for the
purpose of determining whether a proposed project would “exacerbate hazards that are
already present.” It then noted, “Nor, for that matter, does CEQA prohibit an agency
from considering—as part of an environmental review of a project it proposes to
undertake— how existing conditions might impact a project’s future users or residents.
Indeed, it appears that such an analysis had been widely understood to be an integral
aspect of CEQA review for three decades. (OPR: CEQA: The California Environmental
Quality Act: Law and Guidelines 1984 (Jan. 1984) Discussion of amendments, [CEQA]
Guidelines former § 15126, p. 137 [dismissing as early as 1983 the alleged ‘artificial
distinction’ between examining ‘the effects of the project on the environment’ and ‘the
effects of the environment on the project’].” (Building Association, supra, 62 Cal.4th at
p. 388, fn. 12, italics added.)

                                            13
       CBIA suggests the Supreme Court’s reference to “an environmental review for a
project it proposes to undertake” refers to planning and zoning decisions by an agency,
rather than CEQA review as contemplated by the Receptor Thresholds. We do not think
the Supreme Court would have used the term “environmental review” to mean something
other than review under CEQA in a case involving the validity of thresholds of
significance under CEQA, particularly when the sentence that follows notes that an
analysis of how existing conditions might affect future users and residents “had been
widely understood to be an integral aspect of CEQA review for three decades.” (Building
Association, supra, 62 Cal.4th at p. 388, fn. 12.) We therefore construe footnote 12 of
the Building Association decision to mean that while CEQA cannot be used by a lead
agency to require a developer or other agency to obtain an EIR or implement mitigation
measures solely because the occupants or users of a new project would be subjected to
the levels of emissions specified, an agency may do so voluntarily on its own project and
may use the Receptor Thresholds for guidance. (See Rominger v. County of Colusa
(2014) 229 Cal.App.4th 690, 700–701 [county not precluded from arguing it had
voluntarily undertaken environmental review not required by CEQA].)
              2. Exacerbation of Existing Conditions
       District argues the Receptor Thresholds may be applied to any new project to
determine whether it would worsen existing conditions and thus affect future users of the
project. As the Supreme Court explained in Building Association: “[T]he statutory
language [of CEQA] emphasizes how the analysis of a project’s potential to exacerbate
existing conditions is not an exception to, but instead a consequence of, CEQA’s core
requirement that an agency evaluate a project’s impact on the environment. . . . Because
this type of inquiry still focuses on the project’s impacts on the environment—how a
project might worsen existing conditions—directing an agency to evaluate how such
worsened conditions could affect a project’s future users or residents is entirely consistent
with this focus and with CEQA as a whole.” (Building Association, supra, 62 Cal.4th at
p; 389.)


                                             14
       CBIA responds that the Receptor Thresholds are not the appropriate vehicle for
measuring the exacerbating effects of a project on the existing environment. When such
an analysis is required, CBIA argues, the proposed project is a source of environmental
contamination, and its effect within the presumptive 1,000-foot zone of influence
(including its effect upon persons living in or working at the site of the project itself)
would be measured by the Source Thresholds, which are not at issue at this stage of the
appeal. We agree that conceptually, a proposed project that would itself worsen
environmental conditions would be a source—but it would also be a receptor to the extent
it brought users or occupants to the site. The Source Thresholds and Receptor Thresholds
are numerically identical, and would presumably yield the same result when applied to a
project likely to worsen environmental conditions. But while this might render the
Receptor Thresholds redundant in certain cases, it does not mean they could not be used
as a component in measuring the effects of such a project, as discussed in Building
Association.
               3. School Projects under CEQA
       The Supreme Court’s decision in Building Association recognized “[a]lthough
CEQA does not generally require an evaluation of the effects of existing hazards on
future users of the proposed project, it calls for such an analysis” with respect to certain
school projects. (Building Association, supra, 62 Cal.4th at p. 391.) District correctly
argues the Receptor Thresholds could be used by a school district acting as a lead agency
to determine such hazards.
        Public Resources Code section 21151.8, subdivision (a)(1), provides that an EIR
or negative declaration will not be approved for a project involving the purchase of a
school site or the construction of a new elementary or secondary school unless those
documents include information necessary to determine whether the property is located on
certain hazardous sites or within 500 feet from the edge of a freeway or busy traffic
corridor. The school district, as the lead agency, must consult with air quality districts
and other agencies regarding facilities within one-quarter mile of the proposed school site
“that might reasonably be anticipated to emit hazardous emissions or handle hazardous or

                                              15
extremely hazardous substances or waste.” (Pub. Res. Code, § 21151.8, subd. (a)(2)(A).)
When specified facilities or sources of pollution have been identified, the governing
board of the school district must make written findings that “(i) The health risks from the
facilities or other pollution sources do not and will not constitute an actual or potential
endangerment of public health to persons who would attend or be employed at the
proposed school. [¶] (ii) Corrective measures required under an existing order by
another agency having jurisdiction over the facilities or other pollution sources will,
before the school is occupied, result in the mitigation of all chronic or accidental
hazardous air emissions to levels that do not constitute an actual or potential
endangerment of public health to persons who would attend or be employed at the
proposed school. . . . [¶] (iii) For a schoolsite with a boundary that is within 500 feet of
the edge of the closest traffic lane of a freeway or other busy traffic corridor, the
governing board of the school district determines, through analysis pursuant to paragraph
(2) of subdivision (b) of Section 44360 of the Health and Safety Code, based on
appropriate air dispersion modeling, and after considering any potential mitigation
measures, that the air quality at the proposed site is such that neither short-term nor
long-term exposure poses significant health risks to pupils.” (Pub. Res. Code, § 21151.8,
subd. (a)(3)(B)(i)–(iii), italics added.)
       The CEQA review of a school project thus requires the school district to consider
whether specified existing sources of pollution are an “endangerment of public health” of
persons at the school site, whether corrective measures could mitigate this danger, and
whether air quality poses “significant health risks” to students. (Pub. Res.
Code, § 21151.8, subd. (a)(3)(B)(i)–(iii).) The purpose of the Receptor Thresholds is to
determine whether a project will have a significant effect on the environment. A finding
of significance is mandatory if “[t]he environmental effects of a project will cause
substantial adverse effects on human beings, either directly or indirectly.” (Pub. Res.
Code, § 21083, subd. (b)(3); CEQA Guidelines, § 15065(a)(4).) “In other words, while
‘[e]ffects analyzed under CEQA must be related to a physical change’ ([CEQA]
Guidelines, § 15358, subd. (b)), such a change may be deemed significant based solely on

                                              16
its impact on people.” (Parker Shattuck Neighbors v. Berkeley City Council (2013) 222
Cal.App.4th 768, 779 (Parker Shattuck).)
       Although the suggested 1,000-foot zone of influence for the Receptor Thresholds
does not correspond precisely to the quarter-mile (1,320-foot) radius within which
sources of air pollution must be analyzed by a school district under Public Resources
Code section 21151.8, subd. (a)(2)(A), sections 5.1.3 and 5.2.5 of the District Guidelines
recognize a lead agency may “enlarge the 1,000-foot radius on a case-by-case basis . . . .”
Given the confluence of purpose between measuring environmental significance as
contemplated by the Receptor Thresholds, and measuring risks to human health as
contemplated by the CEQA requirements for siting a new school, the levels of air
pollution described by the Receptor Thresholds could be used by a school district to
assess the health risk to students and employees at a proposed school site.3
              4. CEQA Exemptions for Housing Development Projects
       The Public Resources Code exempts certain housing development projects from
CEQA review when, among other things, “[t]he site of the project is subject to a
preliminary endangerment assessment prepared by an environmental assessor to
determine the existence of any release of a hazardous substance on the site and to
determine the potential for exposure of future occupants to significant health hazards
from any nearby property or activity.” (Pub. Res. Code, §§ 21159.21, subd. (f), italics

3
        Another exception to the general rule that CEQA does not require an evaluation of
the effects of existing hazards on future users of a project is Pubic Resources Code
section 21096 (noted in Building Association, supra, 62 Cal.4th at p. 391), which
describes the procedures for “a project situated within airport land use compatibility plan
boundaries, or, if an airport land use compatibility plan has not been adopted, for a
project within two nautical miles within an airport . . . .” (Pub. Res. Code, § 21096, subd.
(a).) It provides in relevant part, “A lead agency shall not adopt a negative declaration
for [such a] project. . . unless the lead agency considers whether the project will result in
a safety hazard or noise problem for persons using the airport or for persons residing or
working in the project area.” (Cal. Pub. Res. Code, § 21096, subd. (b), italics added.)
The Receptor Thresholds concern air quality and emissions rather than safety hazards or
noise problems, and would not appear germane to an analysis of an airport project under
this section. District does not argue otherwise.

                                             17
added; 21159.22, (b)(3) [agricultural housing for employees]; 21159.23, subd. (a)(2)(A)
[low income housing]; 21159.24, subd. (a)(1) & (3) [urban infill projects].) “If a
potential for exposure to significant hazards from surrounding properties or activities is
found to exist, the effects of the potential exposure shall be mitigated to a level of
insignificance in compliance with state and federal requirements.” (Cal. Pub. Res.
Code, § 21159.21, subd. (f)(2).) Transit priority projects are treated similarly. (Pub. Res.
Code, § 21155.1, subd. (a)(4), (a)(4)(B).)
       The Supreme Court in Building Association recognized these CEQA exemption
statutes were exceptions to the general rule that CEQA did not require an evaluation of
existing hazards on future users of a proposed project. (Building Association, supra, 62
Cal.4th at p. 391.) “[T]hese statutes reflect an express legislative directive to consider
whether existing environmental conditions might harm those who intended to occupy a
project site.” (Ibid.) A lead agency charged with CEQA review of a project governed by
these statutes could apply the Receptor Thresholds to determine whether air quality posed
a health risk to future occupants of a qualifying housing project.
       Citing Parker Shattuck, supra, 222 Cal.App.4th at page 781, CBIA argues that
future occupants of a housing project that is potentially eligible for an exemption are not
part of the “environment” for CEQA purposes. This mischaracterizes the issue, which is
not whether such future occupants are, in general, a part of the environment, but whether
the statues at issue create an exception to the general rule that CEQA does not require an
assessment of the environment’s effect on a project. The court in Parker Shattuck
concluded an EIR was not required for a project on a site with toxic soil contamination
absent evidence the environment would be changed by a disturbance of the soil; although
the project was not categorically exempt from CEQA review, “whether a project should
be categorically exempt from CEQA is different from whether the project involves a
significant effect on the environment.” (Parker Shattuck, supra, 222 Cal.App.4th at p.
781.) Here, we are concerned not with the need for an EIR on a specific project, but with
whether the significance levels set forth in the Receptor Thresholds may be used to


                                              18
evaluate whether a housing project was exempt from CEQA review. Consistent with the
reasoning in Building Association, they may be used for this purpose.
              5. Planning Decisions
       District submits the Receptor Thresholds may be used to determine whether a
particular project is consistent with a general plan. A project’s inconsistency with a
general plan does not itself mandate a finding the project will have a significant effect on
the environment (Lighthouse Field Beach Rescue v. City of Santa Cruz (2005) 131
Cal.App.4th 1170, 1207), and we can only speculate as to the ways in which the Receptor
Thresholds might be applied when assessing plan consistency. (See Pacific Legal
Foundation v. California Coastal Com. (1982) 33 Cal.3d 158, 172–174 [issue of whether
certain CEQA guidelines were valid was not a ripe controversy for purposes of
declaratory relief because parties were inviting the court “to speculate as to the type of
developments for which access conditions might be imposed, and then to express an
opinion on the validity and proper scope of such hypothetical exactions” and it was
“sheer guesswork to conclude that the Commission will abuse its authority by imposing
impermissible conditions on any permits required”].) While we do not rule out the
possibility that the Receptor Thresholds might be used by an agency for such a purpose,
District has not provided us with a concrete example of such a use and we do not rely on
this hypothetical purpose in deciding, as we discuss below, that the Receptor Thresholds
are not invalid on their face.
       E. Conclusion and Remedy
       We have concluded a local agency might permissibly apply the measurements
contained in the Receptor Thresholds to an environmental review conducted under
CEQA in certain cases, even though the Receptor Thresholds cannot be used to require
an EIR or the implementation of mitigating measures based solely on the impact the
existing environment will have on future users or occupants of a project. CBIA argues
that notwithstanding these permissible uses, the Receptor Guidelines must be set aside in
their entirety because the District did not adopt them for the reasons now articulated.


                                             19
District, on the other hand, urges us to leave the Receptor Thresholds in place so they can
be utilized when appropriate.
       The Receptor Thresholds are simply numbers indicating when a project will
ordinarily pose a risk to human health that will be deemed environmentally significant for
CEQA purposes. CEQA requires or allows such an analysis with respect to the receptors
of certain projects at various junctures in the environmental review process, but does not
require such an analysis in other contexts. The Receptor Thresholds may be used by lead
agencies to the extent permissible under CEQA, but any effort by an agency to require an
EIR, mitigating measures, or other CEQA review under the Receptor Thresholds when
one is not authorized would be subject to a strong legal challenge.
       Because the Receptor Thresholds themselves may be used under certain
circumstances consistent with CEQA, they are not “clearly erroneous and unauthorized”
(Building Association, supra, 62 Cal.4th at p. 390) and need not be set aside in their
entirety. However, the District Guidelines are misleading to the extent they contemplate
an application of the Receptor Thresholds to evaluate the effect of the existing
environment on all new receptors as a matter of course, a use that would be inconsistent
with CEQA as interpreted by the Supreme Court in Building Association, supra, 62
Cal.4th 369.
       We will remand the case to the trial court with instructions to partially grant
CBIA’s petition for writ of mandate, and issue an order invalidating those portions of the
District Guidelines suggesting that lead agencies should apply the Receptor Thresholds to
routinely assess the effect of existing environmental conditions on future users or
occupants of a project. The trial court may also consider and determine in the first
instance the extent to which CBIA may be entitled to declaratory relief regarding the
Receptor Thresholds and the limits to be placed upon their use. (Code Civ. Proc.,
§ 1060.)
       F. Attorney Fees
       After the trial court initially entered judgment in favor of CBIA and granted its
petition for writ of mandate directing District to set aside is approval of the Thresholds, it

                                             20
awarded CBIA attorney fees under Code of Civil Procedure section 1021.5. Under that
statute, which codifies the private attorney general doctrine, attorney fees are available
“to a successful party against one or more opposing parties in any action which has
resulted in the enforcement of an important right affecting the public interest if: (a) a
significant benefit, whether pecuniary or nonpecuniary, has been conferred on the general
public or a large class of persons, (b) the necessity and financial burden of private
enforcement, or of enforcement by one pubic entity against another public entity, are
such as to make the award appropriate, and (c) such fees should not in the interest of
justice be paid out of the recovery, if any.”
       Although we reversed the initial judgment in CBIA’s favor and accordingly
reversed the trial court’s award of attorney fees, CBIA has now prevailed in part on one
of the issues it raised in this proceeding. Partially successful plaintiffs may recover
attorney fees under Code of Civil Procedure section 1021.5. (Lyons v. Chinese Hospital
Assn (2006) 136 Cal.App.4th 1331, 1345.)
       We agree with CBIA that its claim for attorney fees under Code of Civil Procedure
section 1021.5 should be considered by the trial court in the first instance. (Arden
Carmichael, Inc. v. County of Sacramento (2000) 79 Cal.App.4th 1070, 1079–1080
[“Whether a party is entitled to an award of attorney fees under the private attorney
general statute is an issue best decided in the first instance by the trial court”]. The trial
court should determine CBIA’s entitlement to attorney fees on appeal and the amount of
any such fees (including fees for proceedings in the Supreme Court), in addition to the
fees it awards, if any, for the litigation in the trial court. (See Bjornestad v. Hulse (1991)
229 Cal.App.3d 1568, 1598–1599.)4




4
       CBIA’s request for judicial notice, filed April 22, 2016, is denied as unnecessary
to our analysis. District’s request for judicial notice filed on May 6, 2016, in support of
its opposition to CBIA’s request for judicial notice, is denied as moot.


                                                21
                                       DISPOSITION
       The trial court’s judgment entered on March 12, 2012, which granted CBIA’s
petition for writ of mandate and directed District to set aside its approval of the
Thresholds in their entirety, is reversed, consistent with our prior opinion in this case.
The case is remanded to the trial court for further action consistent with this opinion and
the Supreme Court’s decision in Building Association, supra, 62 Cal.4th 369, including
but not limited to the issuance of an order partially granting CBIA’s petition for writ of
mandate. The trial court shall also consider CBIA’s request for attorney fees under Code
of Civil Procedure section 1021.5 in light of the proceedings in the trial court and on
appeal. The parties shall bear their own costs on this appeal. (Cal. Rules of Court, rule
8.278(a)(3).)




                                              22
                          NEEDHAM, J.




We concur.




JONES, P.J.




BRUINIERS, J.




(A135335, A136212)


                     23
Superior Court of Alameda County, No. RG10-548693, Frank Roesch, Judge.

Shute, Mihaly & Weinberger, Ellison Folk, Erin B. Chalmers and Brian C. Bunger for
Defendant and Appellant.

Ruby R. Fernandez for South Coast Air Quality District as Amicus Curiae on behalf of
Defendant and Appellant.

Paula A. Forbis for County of San Diego as Amicus Curiae on behalf of Defendant and
Appellant.

Matthew D. Vespa for Sierra Club and Center for Biological Diversity as Amicus Curiae
on behalf of Defendant and Appellant.

Burke, Williams & Sorensen and Thomas B. Brown for League of California Cities and
California State Association of Counties as Amicus Curiae on behalf of Defendant and
Appellant.

Cox, Castle & Nicholson, Andrew B. Sabey, Christian Cebrian, Michael H. Zischke and
Bradley B. Brownlow for Plaintiff and Respondent.

Perkins Coie and Geoffrey L. Robinson for Center for Creative Land Recycling as
Amicus Curiae on behalf Plaintiff and Respondent.




                                          24
