[Federal Register Volume 81, Number 169 (Wednesday, August 31, 2016)]
[Rules and Regulations]
[Pages 59876-59901]
[FR Doc No: 2016-20413]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R09-OAR-2014-0636; FRL-9951-42-Region 9]

Approval and Promulgation of Air Quality State Implementation
Plans; California; San Joaquin Valley; Moderate Area Plan for the 2006
PM2.5 NAAQS

AGENCY: U.S. Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: The Environmental Protection Agency (EPA) is approving
elements of the state implementation plan revisions (SIP) submitted by
California to address Clean Air Act requirements for the 2006 fine
particulate matter (PM2.5) National Ambient Air Quality
Standards in the San Joaquin Valley Moderate PM2.5
nonattainment area. These SIP revisions are the 2012 PM2.5
Plan, submitted March 4, 2013, the 2014 Supplement, submitted November
6, 2014, and the

motor vehicle emission budgets for the 2006 PM2.5 NAAQS
submitted November 13, 2015. The EPA is disapproving interpollutant
trading ratios identified in the SIP submission for nonattainment new
source review permitting purposes because the ratios are not supported
by a sufficient technical demonstration.

DATES: This rule is effective on September 30, 2016.

ADDRESSES: The EPA has established a docket for this action under
Docket ID No. EPA-R09-OAR-2014-0636. All documents in the docket are
listed on the http://www.regulations.gov Web site. Although listed in
the index, some information is not publicly available, e.g., CBI or
other information whose disclosure is restricted by statute. Certain
other material, such as copyrighted material, is not placed on the
Internet and will be publicly available only in hard copy form.
Publicly available docket materials are available through http://www.regulations.gov, or please contact the person identified in the For
Further Information Contact section for additional availability
information.

FOR FURTHER INFORMATION CONTACT: Wienke Tax, EPA Region 9, (415) 947-
4192<EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us'' and
``our'' refer to the EPA.

Table of Contents

I. Background
II. Public Comments and the EPA's Responses
III. Final Action
IV. Statutory and Executive Order Reviews

I. Background

A. Proposed Action

    On January 13, 2015, we proposed to approve SIP revisions submitted
by California to address Clean Air Act (CAA or ``the Act'')
requirements for the 2006 primary and secondary 24-hour
PM2.5 national ambient air quality standards (NAAQS or
``standards'') in the San Joaquin Valley (SJV) PM2.5
nonattainment area.\1\ These SIP revisions are the 2012
PM2.5 Plan, submitted March 4, 2013, and the ``Supplemental
Document, Clean Air Act Subpart 4: The 2012 PM2.5 Plan for
the 2006 PM2.5 Standard, and District Rule 2201 (New and
Modified Stationary Source Review)'' (2014 Supplement), submitted
November 6, 2014. We also proposed to approve, through parallel
processing, the proposed motor vehicle emissions budgets (MVEBs) for
the 2006 PM2.5 NAAQS submitted on November 6, 2014, which
California submitted in final form on December 29, 2014, and the
related trading mechanism for transportation conformity purposes. We
refer to these submissions collectively herein as ``the 2012
PM2.5 Plan'' or simply ``the Plan.''
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    \1\ 80 FR 1816 (January 13, 2015).
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    The EPA proposed to approve the following elements of the 2012
PM2.5 Plan as satisfying applicable CAA requirements: (1)
The 2007 base year emissions inventories, (2) the demonstration that
attainment by the Moderate area attainment date of December 31, 2015 is
impracticable, (3) the reasonably available control measures/reasonably
available control technology (RACM/RACT) demonstration, (4) the
reasonable further progress (RFP) demonstration, (5) the San Joaquin
Valley Unified Air Pollution Control District's (SJVUAPCD's or
``District's'') commitments to adopt and implement specific rules and
measures by specific dates, and (6) the 2014 and 2017 MVEBs for direct
PM2.5 and oxides of nitrogen (NOX). The EPA also
proposed to determine that volatile organic compounds (VOC) emissions
do not contribute significantly to ambient PM2.5 levels that
exceed the 2006 PM2.5 NAAQS in the SJV but to find the
State's and District's demonstration concerning ammonia emissions
insufficient to rebut the regulatory presumption for ammonia.
    The EPA proposed to disapprove interpollutant trading ratios
identified in these SIP submittals for nonattainment new source review
(NNSR) permitting purposes. Finally, the EPA proposed to reclassify the
SJV area, including Indian country within it, as a Serious
nonattainment area for the 2006 PM2.5 NAAQS, based on the
EPA's determination that the area could not practicably attain these
standards by the applicable Moderate area attainment date of December
31, 2015.

B. Final Reclassification of the SJV Area From Moderate to Serious for
the 2006 PM2.5 NAAQS

    On December 22, 2015, we finalized our January 13, 2015 proposal to
reclassify the SJV area from Moderate to Serious for the 2006
PM2.5 NAAQS.\2\ As a result of that action, by August 21,
2017, California is required to submit additional SIP revisions to
satisfy the statutory requirements that apply to Serious
PM2.5 nonattainment areas, including the requirements of
subpart 4 of part D, title I of the Act. The Serious area plan must
provide for attainment of the 2006 PM2.5 NAAQS in the SJV
area as expeditiously as practicable, but no later than December 31,
2019, in accordance with the requirements of part D of title I of the
Act.
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    \2\ 81 FR 2993 (January 20, 2016) (final rule) and 81 FR 42263
(June 29, 2016) (correcting amendment).
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C. Motor Vehicle Emissions Budgets in the 2012 PM2.5 Plan

    As part of our January 13, 2015 proposed action, we proposed to
approve the proposed 2014 and 2017 MVEBs for the 2006 PM2.5
NAAQS submitted by the California Air Resources Board (CARB) on
November 6, 2014 with a request for parallel processing. CARB formally
submitted the final budgets to the EPA on December 29, 2014.\3\ On
April 1, 2016, we found the NOX and direct PM2.5
budgets in the 2012 PM2.5 Plan and 2014 Supplement, as
submitted December 29, 2014, to be adequate for conformity purposes.\4\
On November 13, 2015, CARB submitted a SIP revision to replace several
previously-submitted MVEBs developed using EMFAC2011 with revised MVEBs
developed using EMFAC2014.\5\
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    \3\ Letter dated December 29, 2014, from Richard W. Corey,
Executive Officer, CARB, to Jared Blumenfeld, Regional
Administrator, EPA Region 9, with enclosures.
    \4\ Letter dated April 1, 2016, from Deborah Jordan, Director,
Air Division, EPA Region 9, to Richard W. Corey, Executive Officer,
CARB, and 81 FR 22194 (April 15, 2016).
    \5\ Letter dated November 13, 2015, from Richard W. Corey,
Executive Officer, CARB, to Jared Blumenfeld, Regional
Administrator, EPA Region 9, with enclosures.
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    On May 18, 2016, we proposed to approve the revised MVEBs submitted
on November 13, 2015, which address the 1997 8-hour ozone standards,
the 2006 PM2.5 standards, and the 1987 coarse particulate
matter (PM10) standard for the SJV area.\6\ We received no
public comments on this proposal. Today, we are finalizing action only
on the revised 2017 MVEBs addressing the 2006 PM2.5 NAAQS in
the SJV, as submitted November 13, 2015.\7\ These NOX and
direct PM2.5 budgets were revised using EMFAC2014, the most
recent version of California's motor vehicle emission factor model
approved by the EPA for use in SIPs and conformity analyses.\8\ The
revised budgets, presented in Table 1 below, were developed in
consultation with the

SJVUAPCD, the eight SJV metropolitan planning organizations (MPOs), the
EPA and CARB. These budgets replace the NOX and direct
PM2.5 budgets submitted on December 29, 2014.
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    \6\ 81 FR 31212 (May 18, 2016).
    \7\ The EPA took final action on the revised ozone and
PM10 budgets at 81 FR 53294 (August 12, 2016). Although
the 2012 PM2.5 Plan contained MVEBs for both 2014 and
2017, MVEBs for 2014 are no longer relevant for conformity analyses
since that year has passed.
    \8\ 80 FR 77337 (December 14, 2015).

  Table 1--San Joaquin Valley Revised Budgets Developed Using EMFAC2014
------------------------------------------------------------------------
                                                  2017 (tons per winter
                                                          day)
                    County                     -------------------------
                                                   PM2.5         NOX
------------------------------------------------------------------------
Fresno........................................          1.0         32.1
Kern (SJV)....................................          0.8         28.8
Kings.........................................          0.2          5.9
Madera........................................          0.2          6.0
Merced........................................          0.3         11.0
San Joaquin...................................          0.6         15.5
Stanislaus....................................          0.4         12.3
Tulare........................................          0.4         11.2
------------------------------------------------------------------------
Note: CARB calculated the revised PM2.5 budgets by taking the sum of the
  county-by-county emissions results from EMFAC and rounding the SJV-
  wide total up to the nearest whole ton for NOX and to the nearest
  tenth of a ton for direct PM2.5, then reallocating to the individual
  counties based on the ratio of each county's contribution to the
  total, and then rounding each county's emissions to the nearest tenth
  of a ton using the conventional rounding method. The existing adequate
  PM2.5 budgets submitted December 29, 2014 were calculated in the same
  manner.

    As part of our January 13, 2015 proposed action, the EPA also
proposed to approve, in accordance with 40 CFR 93.124, the trading
mechanism as described on p. C-32 in Appendix C of the 2012
PM2.5 Plan as an enforceable component of the transportation
conformity program for the SJV for the 2006 PM2.5 NAAQS,
with the condition that trades are limited to substituting excess
reductions in NOX for increases in PM2.5. This
trading mechanism was not revised by the November 13, 2015 MVEB
submittal.\9\ We are finalizing our proposal to approve the trading
mechanism identified in the Plan for transportation conformity
purposes.
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    \9\ 81 FR 31212, 31218 (May 18, 2016).
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    The budgets that the EPA is approving herein relate to the 2006
PM2.5 NAAQS only, and our approval of them does not affect
the status of the previously-approved MVEBs for the 1997
PM2.5 NAAQS and related trading mechanism, which remain in
effect for that PM2.5 NAAQS.

II. Public Comments and the EPA's Responses

    The EPA provided a 45-day period for the public to comment on our
proposed rule. During this comment period, which ended on February 27,
2015, we received two sets of public comments, one from the SJVUAPCD
and another from Earthjustice on behalf of the Central Valley Air
Quality Coalition, Greenaction, the Association of Irritated Residents,
the Sierra Club--Tehipite Chapter, and Global Community Monitor
(Earthjustice).\10\ Copies of these comment letters can be found in the
docket.
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    \10\ See letter dated February 27, 2015 from Sheraz Gill,
Director of Strategies and Incentives at SJVAPCD, to Wienke Tax, EPA
Region 9, ``Re: Docket No. EPA-R09-OAR-2014-0636, Comments on
Proposed Approval and Promulgation of Implementation Plans;
Designation of Areas for Air Quality Planning Purposes; California;
San Joaquin Valley Moderate Area Plan and Reclassification as
Serious Nonattainment for the 2006 PM2.5 NAAQS,'' and
letter dated February 27, 2015 from Paul Cort and Adenike Adeyeye,
Earthjustice, to Ms. Wienke Tax, Air Planning Office, EPA Region 9.
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    In our December 22, 2015 final action to reclassify the SJV area as
a ``Serious'' PM2.5 nonattainment area, we summarized and
responded to public comments pertaining to the reclassification and its
consequences and stated that we would, in a separate rulemaking,
respond to comments pertaining to our proposed action on the submitted
plan.\11\ In our April 15, 2016 notice of adequacy, we responded to a
public comment pertaining to the adequacy of the budgets.\12\
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    \11\ 81 FR 2993 (January 20, 2016).
    \12\ 81 FR 22194 (April 15, 2016).
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    We summarize below and provide our responses to all remaining
public comments on our proposed action on the 2012 PM2.5
Plan.

A. Comment Regarding Emissions Inventories

    Comment 1: Earthjustice comments on the importance of emissions
inventories, noting that CAA section 172(c)(3) requires that
nonattainment plans ``include a comprehensive, accurate, current
inventory of actual emissions from all sources of the relevant
pollutant or pollutants in such area'' (emphasis by commenter).
Earthjustice argues that the EPA's proposed determination that the 2012
PM2.5 inventories ``are based on the most current and
accurate information available to the State and District at the time
the Plan and its inventories were being developed,'' does not satisfy
the requirements of section 172(c)(3) that the inventory be accurate
and current. While acknowledging that it is unaware of information
calling into question the inventories used in the Plan, Earthjustice
asserts that the EPA must take further steps to confirm that the
inventories ``are'' (i.e., remain) current and accurate before it
approves the inventories. Citing Sierra Club v. United States EPA, 671
F.3d 955, 968 (9th Cir. 2012), Earthjustice states that the EPA's
failure to confirm that the inventories are current and accurate
``undermines the rational basis for the approval.''
    Response 1: The EPA does not dispute the importance of emissions
inventories. We evaluated the emissions inventories in the 2012
PM2.5 Plan to determine whether they satisfy the
requirements of CAA section 172(c)(3) and adequately support the Plan's
RACM, RFP, and impracticability demonstrations. Based on this
evaluation, we have concluded that the Plan's 2007 base year emissions
inventory was based on the most current and accurate information
available to the State and District at the time the Plan was developed
and submitted, and that it comprehensively addresses all source
categories in the SJV area, consistent with applicable CAA requirements
and EPA guidance.\13\
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    \13\ 80 FR 1816 at 1819-1820; see also ``General Preamble for
Implementation of Title I of the Clean Air Act Amendments of 1990,''
57 FR 13498, 13502 (April 16, 1992) (``General Preamble'').
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    CAA section 172(b) provides that a state containing a nonattainment
area shall submit a plan or plan revision (including the plan items)
meeting the applicable requirements of CAA section 172(c) and section
110 on the schedule established by the EPA. Section 172(c) contains,
inter alia, the requirement that nonattainment area plans include a
``comprehensive, accurate, current inventory'' of actual emissions from
all sources of the relevant pollutant or pollutants in the area. We
believe it is reasonable to read these provisions together as requiring
that the state submit an inventory that is comprehensive, accurate, and
current at the time the state submitted it to the EPA, rather than
requiring that the state continually revise its plan as new emissions
data become available.\14\ Air quality planning is an iterative process
and states and the EPA must rely on the best available data at the time
the plans are created. Nothing in the Sierra Club decision cited by the
commenters (671 F.3d 955, 9th Cir. 2012) compels the EPA to alter this
longstanding interpretation of the CAA.\15\
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    \14\ EPA, Office of Transportation and Air Quality (OTAQ),
``Policy Guidance on the Use of MOVES2010 for State Implementation
Plan Development, Transportation Conformity, and Other Purposes,''
December 2009; see also Memorandum from John Seitz, EPA, Office of
Air Quality Planning and Standards and Margo Oge, OTAQ, ``Policy
Guidance on the Use of MOBILE6 for SIP Development and
Transportation Conformity,'' January 18, 2002.
    \15\ In Sierra Club v. EPA, 671 F.3d 955 (9th Cir. 2012), the
Ninth Circuit remanded the EPA's final action approving an ozone
plan for the SJV on the ground that the EPA's failure to consider
new inventory data submitted by CARB long before the EPA's action on
the plan was arbitrary and capricious under the Administrative
Procedure Act. See 671 F.3d at 966 (``EPA stands on shaky legal
ground relying on significantly outdated data, given the amount of
time that EMFAC2007 was available and authorized for use before the
EPA approved the 2004 SIP''). The decision did not disturb the EPA's
longstanding policy of requiring states to use the most current
emissions estimate models available at the time of SIP development.

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B. Comments Regarding Precursors

    Comment 2: The SJVUAPCD argues that ammonia is not a significant
precursor for PM2.5 and that additional ammonia controls are
not required. The District asserts that the EPA's proposal to reject
these findings is based on ``technical assertions not supported by the
extensive scientific research and modeling'' conducted for the Plan,
and that the technical analyses in the Plan demonstrate that ammonia
reductions are ineffective for attaining the PM2.5 NAAQS.
Although the District recognizes that ammonia is an integral component
of ammonium nitrate, which contributes substantially to wintertime
PM2.5 mass in the SJV, it argues that its scientific
evaluations in the Plan provide ``sufficient substantiation that
controls on ammonia are known to be very insensitive to reducing
ammonium nitrate mass concentrations.'' The District also comments that
the EPA did not provide references or support for statements in its
technical support document that ``a detailed evaluation of the modeling
shows that ammonia controls can be effective at reducing ambient
PM2.5 in some locations,'' and that ``[i]n the various
studies, when ammonia emissions were reduced by up to 50 percent,
ambient ammonium nitrate decreased by 5 to 25 percent, depending on the
episode modeled and the geographic location evaluated . . . . These
percentages for ammonia benefits are generally smaller than those for
NOX reductions, but these modeling results show that
reductions in ammonia emissions under certain circumstances can
effectively reduce ambient PM2.5'' (internal citations
omitted). The District argues that these statements are contrary to the
Plan's Weight of Evidence Analysis in Appendix G of the 2012
PM2.5 Plan.
    Response 2: We disagree with the District's claim that we did not
provide support for our conclusions about ammonia impacts in the SJV.
As stated on pg. 56 of the EPA's technical support document (TSD) for
the proposed rule (hereafter ``Proposal TSD''),\16\ the EPA's
conclusion that ammonia controls can be effective at reducing ambient
PM2.5 in some locations in the SJV is based on (1)
sensitivity to ammonia reductions in the air quality modeling and
Weight of Evidence Analysis in the 2012 PM2.5 Plan, (2) a
number of peer-reviewed journal papers cited in the Plan showing
ammonium nitrate reductions of up to 25 percent when ammonia emissions
are reduced by 50 percent, and (3) the severity of PM2.5
nonattainment in the area.\17\
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    \16\ EPA, Region 9, Air Division, Technical Support Document,
``Proposed Action on the San Joaquin Valley 2012 PM2.5
State Implementation Plan and 2014 Supplemental Document and
Proposed Reclassification of the San Joaquin Valley as Serious
Nonattainment for the 2006 PM2.5 Standard,'' December
2014 [``Proposal TSD''].
    \17\ Id. at p. 56.
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    Comment 3: The SJVUAPCD recognizes that ammonia is a large
component of ammonium nitrate and that ammonium nitrate contributes
substantially to wintertime PM2.5 mass, but asserts that
this does not necessarily mean that reductions in ammonia emissions are
effective in reducing PM2.5 concentrations in the SJV.
Similarly, the District acknowledges that ammonia is found in the SJV
at higher wintertime concentrations than NOX but states that
ammonia's physical abundance does not solely determine its significance
as a precursor. The District cites language in the EPA's Proposal TSD
stating that the EPA reviews a determination to exclude a
PM2.5 precursor by considering both ``the magnitude of the
precursor's contribution to ambient PM2.5 concentrations''
and ``the sensitivity of ambient PM2.5 concentrations in the
area to reductions in emissions of that precursor.'' The District
interprets this language to establish two necessary elements for
precursor significance: (1) A ``relatively high contribution'' to
overall PM2.5 mass, and (2) availability of control
mechanisms for the precursor that demonstrate a ``reasonable rather
than negligible'' reduction in PM2.5 mass. The District
asserts that PM2.5 concentrations in the SJV are highly
insensitive to ammonia controls, particularly when compared to
alternative controls on NOX, which it claims is the limiting
precursor for ammonia nitrate formation. While the District agrees with
the EPA that the decision of whether to require reductions of a
precursor should not be based solely on the control effectiveness of
the precursor relative to other precursors, the District comments that
an ``additional key issue that must also be taken under consideration
is the development and implementation of effective emission reductions
strategies for reducing ambient PM2.5 and bringing the [SJV]
into attainment.''
    Response 3: The EPA generally agrees with the District's statement
that both the contribution of a precursor to PM2.5
concentrations in the area and the area's sensitivity to reductions in
emissions of the precursor may be relevant for assessing the level of
contribution of a PM2.5 precursor to ambient
PM2.5 levels. The EPA also agrees with the District's
conclusion that ambient PM2.5 concentrations are more
sensitive to NOX emission reductions than to ammonia
emission reductions. We disagree, however, with the District's
suggestion that the effectiveness of reductions of a particular
precursor in improving PM2.5 air quality relative to a
different precursor may support a conclusion that a given precursor
does not contribute significantly to ambient PM2.5 levels
that exceed the NAAQS. We also disagree with the District's suggestion
that the ``availability of control mechanisms for the precursor that
demonstrate a `reasonable rather than negligible' reduction in
PM2.5 mass'' is a necessary consideration in determining
whether a particular PM2.5 precursor is subject to control
evaluation under subpart 4.
    As explained in our proposed rule, ammonia is a precursor to the
formation of PM2.5 and is, therefore, presumptively
regulated under subpart 4 of part D, title I of the Act.\18\ Thus, CARB
and the District must evaluate ammonia emissions for potential controls
unless the State submits a demonstration adequate to rebut the
regulatory presumption in the SJV area. The pertinent question in a
demonstration to rebut the regulatory presumption for ammonia is
whether ammonia emission sources ``contribute significantly'' to
PM2.5 levels that exceed the PM2.5 NAAQS in the
SJV, not whether existing emission control measures can achieve a
specified amount of emission reductions in the area or how effective
ammonia reductions are compared to reductions of other PM2.5
precursors.\19\ More specifically, with respect to the sensitivity-
based contribution analysis, the pertinent question is whether
PM2.5 concentrations in the nonattainment area are
``insensitive'' to emissions reductions of the precursor.\20\ We note
that the EPA may, in some cases, require a state to identify and
evaluate potential control measures to reduce emissions of a particular
PM2.5 precursor from existing sources as part of a
sensitivity-based contribution analysis, i.e., in order to adequately
demonstrate that regulation of the precursor would not

provide meaningful improvements in ambient air quality.\21\
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    \18\ 80 FR 1816, 1821 (January 13, 2015) (citing NRDC v. EPA,
706 F.3d 428 (D.C. Cir. 2013)).
    \19\ CAA section 189(e).
    \20\ See EPA, Final Rule, ``Fine Particulate Matter National
Ambient Air Quality Standards: State Implementation Plan
Requirements,'' July 29, 2016 (pre-publication notice) at Section
III.C.3.d, pp. 50-54 (discussing technical issues associated with
sensitivity-based contribution analysis).
    \21\ See EPA, Final Rule, ``Fine Particulate Matter National
Ambient Air Quality Standards: State Implementation Plan
Requirements,'' July 29, 2016 (pre-publication notice) at 40 CFR
51.1009(a)(2)(ii). Although this regulatory text is not yet
effective, it reflects the EPA's interpretation of the statutory
requirements. See also EPA, Response to Comments on the Fine
Particulate Matter National Ambient Air Quality Standards: State
Implementation Plan Requirements, July 29, 2016, at p. 23 (noting
that ``while a valid sensitivity-based precursor demonstration
generally will not require an evaluation of available controls, the
EPA may determine, based on the facts and circumstances of the area,
that the state needs to conduct a control measure evaluation for the
relevant precursor to adequately demonstrate that regulation of the
precursor would not provide meaningful reductions in ambient air
quality'').
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    Given the severity of PM2.5 nonattainment in the SJV
area, the ambient contribution of ammonia emissions, the area's
demonstrated sensitivity to ammonia control,\22\ and our finding that
the precursor demonstration in the Plan is insufficient to rebut the
regulatory presumption for ammonia, we conclude that ammonia emissions
contribute significantly to ambient PM2.5 levels that exceed
the PM2.5 NAAQS in the SJV area and that the 2012
PM2.5 Plan must, therefore, contain an evaluation of
potential ammonia controls.
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    \22\ Proposal TSD at p. 57; see also 80 FR 1816, 1825 (January
13, 2015).
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    Comment 4: Earthjustice challenges the EPA's method for identifying
PM2.5 precursors subject to regulation by the Plan.
Specifically, Earthjustice objects to the EPA's consideration of ``both
the magnitude of the precursor's contribution to ambient
PM2.5 concentrations in the nonattainment areas and the
sensitivity of ambient PM2.5 concentrations in the area to
reductions in emissions of that precursor.'' Earthjustice argues that
this language differs from CAA section 189(e), which provides that
control requirements shall apply to major stationary sources of
particulate matter (PM) precursors unless the EPA finds that these
sources ``do not contribute significantly to PM-10 levels which exceed
the standard in the area.'' Thus, according to Earthjustice, ``the
statute allows for consideration only of the significance of the
contribution'' and does not allow for consideration of the
effectiveness of controls in determining whether a precursor must be
subject to control.
    Earthjustice also characterizes the EPA's consideration of the
sensitivity of ambient concentrations to precursor emissions reductions
as a ``bad'' policy assessment and argues that ``looking merely at the
sensitivity ratios ignores the fact that pollutants like ammonia have
been historically under-regulated and very well may represent the
cheapest opportunities for emission reductions.'' Earthjustice argues
that even if much larger amounts of ammonia reductions would be
required to achieve the benefits of a few tons of NOX
reductions, ammonia controls may still be the ``best'' policy option
because incremental NOX emissions, which have already been
heavily regulated, may be much more expensive. Earthjustice claims that
the EPA's sensitivity test is a policy-based test but that it is not a
rational policy test, because it does not consider the full regulatory
context. According to Earthjustice, ``decisions on how to balance
controls on sources of ammonia versus sources of NOX are for
the control strategy of the Plan,'' and that if additional reductions
beyond those achieved through the required RACM or BACM controls are
necessary, ``that is where the `effectiveness' of the controls can and
should be considered--not in the determination of whether a pollutant
is a precursor subject to control under the Act.''
    Earthjustice states that the EPA has correctly proposed to
determine that ammonia emissions ``contribute significantly'' to
PM2.5 nonattainment in the SJV given that ammonium nitrate
is the largest component of the Valley's PM2.5 levels. Thus,
according to Earthjustice, ammonia controls are mandated under CAA
section 189(e) regardless of the relative sensitivity of ambient
concentrations to emission reductions.
    Response 4: We disagree with the commenter's characterization of
the legal test for determining whether or not a particular
PM2.5 precursor must be subject to control evaluation. With
respect to ammonia emissions, however, this issue does not affect our
action on the 2012 PM2.5 Plan because the EPA is not
determining that ammonia emission sources ``do not contribute
significantly'' to PM2.5 levels that exceed the 2006
PM2.5 NAAQS in the SJV area. Instead, the EPA has concluded
that the State's and District's demonstration concerning ammonia
emissions in the 2012 PM2.5 Plan and 2014 Supplement is
insufficient to rebut the regulatory presumption under subpart 4 and
that ammonia is, therefore, a PM2.5 precursor subject to
control evaluation for purposes of attaining the 2006 PM2.5
NAAQS in the SJV.
    As explained in our proposed rule, section 189(e) of the Act
requires that the control requirements for major stationary sources of
direct PM10 also apply to major stationary sources of
PM10 precursors, except where the Administrator determines
that such sources do not contribute significantly to PM10
levels that exceed the standard in the area. Section 189(e) contains
the only express exception to the control requirements under subpart 4
(e.g., requirements for RACM and RACT, best available control measures
(BACM) and best available control technology (BACT), most stringent
measures, and NSR) for sources of direct PM2.5 and
PM2.5 precursor emissions. Although section 189(e)
explicitly addresses only major stationary sources, the EPA interprets
the Act as authorizing it also to determine, under appropriate
circumstances, that regulation of specific PM2.5 precursors
from other source categories in a given nonattainment area is not
necessary. For example, under the EPA's longstanding interpretation of
the control requirements that apply to stationary, area, and mobile
sources of PM10 precursors area-wide under CAA section
172(c)(1) and subpart 4 (see General Preamble, 57 FR 13498 at 13539-
42), a state may demonstrate in a SIP submittal that control of a
certain precursor pollutant is not necessary in light of its
insignificant contribution to PM10 levels in the
nonattainment area.\23\
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    \23\ 80 FR 1816, 1821-1822 (January 13, 2015). Courts have
upheld this approach to the requirements of subpart 4 for
PM10. See, e.g., Assoc. of Irritated Residents v. EPA, et
al., 423 F.3d 989, 997 (9th Cir. 2005) (noting discretion vested in
the EPA to consider various factors in determining whether a
precursor ``contributes significantly'' to PM10 levels).
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    We evaluated the SJV PM2.5 Plan in accordance with the
presumption embodied within subpart 4 that all PM2.5
precursors must be addressed in the state's evaluation of potential
control measures, unless the state adequately demonstrates that
emissions of a particular precursor do not ``contribute significantly''
to ambient PM2.5 levels that exceed the PM2.5
NAAQS in the nonattainment area. Both the magnitude of a precursor's
contribution to ambient PM2.5 concentrations in the
nonattainment area and the sensitivity of ambient PM2.5
concentrations in the area to reductions in emissions of that precursor
may be relevant to an assessment of whether the precursor contributes
significantly to ambient PM2.5 levels that exceed the
PM2.5 NAAQS in the area. As explained in the preamble to the
EPA's July 29, 2016 final rule to implement the PM2.5 NAAQS:

The EPA . . . believes that a sensitivity-based contribution
analysis is consistent with the language and intent of CAA section
189(e). As applied to attainment plans, CAA section 189(e) allows
states to evaluate whether PM2.5 precursors significantly

contribute to levels which exceed the standard in the area. The
intent of CAA section 189(e) in applying control requirements to
PM2.5 precursors is to ensure expeditious attainment of
the standard. However, if conditions in a particular area are such
that control of sources of one or more precursors does not reduce
PM2.5 concentrations in the area, then those controls
will not help the area attain (expeditiously or otherwise).
Therefore, the EPA disagrees with commenters who argue that
sensitivity-based contribution analyses are not appropriate for
determining if precursors do not significantly contribute to
PM2.5 levels in the area. The EPA believes that
sensitivity-based contribution analyses can be useful for
determining whether adoption of control requirements for sources of
a particular precursor would be effective in reducing
PM2.5 concentrations, and can be useful for determining
whether potential emissions increases under the NNSR program would
lead to insignificant air quality changes. For this reason, the
final rule allows states to conduct sensitivity-based contribution
analyses for the comprehensive, major stationary source, and NNSR
precursor demonstrations.\24\
---------------------------------------------------------------------------

    \24\ EPA, Final Rule, ``Fine Particulate Matter National Ambient
Air Quality Standards: State Implementation Plan Requirements,''
July 29, 2016 (pre-publication notice) at Section III.C, p. 59.

    Based on our evaluation of the precursor demonstrations in the 2012
PM2.5 Plan, we agree with Earthjustice's claim that ammonia
emission sources ``contribute significantly'' to PM2.5
levels that exceed the PM2.5 NAAQS in the SJV and that an
ammonia control evaluation is therefore necessary to satisfy the
requirements of the Act for the 2006 PM2.5 NAAQS. For the
reasons provided in our proposed rule, however, we conclude that VOC
emissions do not ``contribute significantly'' to ambient
PM2.5 levels that exceed the 2006 PM2.5 NAAQS in
the SJV area and that a VOC control evaluation therefore is not
necessary in this Plan. As the commenter has not raised any specific
concern regarding our proposal on VOC emissions, we are not addressing
these issues further with respect to VOCs.
    Comment 5: The District states that it is important to acknowledge
the public health co-benefits of reducing NOX emissions in
the region. The District states that ozone production in the SJV is
limited by NOX concentrations relative to VOC
concentrations, and that NOX reductions typically involve
the elimination, reduction, and/or control of hydrocarbon combustion
sources, and produce net reductions in direct particulates, metals,
organic carbon, elemental carbon, and hazardous air pollutants. The
District asserts that reductions in secondary ammonium nitrate are not
accompanied by these additional co-benefits.
    Response 5: We agree with the commenter that it is important to
reduce NOX emissions for improved public health in the San
Joaquin Valley, because it is a precursor to both PM2.5 and
ozone. As to the air quality benefits of reductions in secondary
ammonium nitrate, theoretically these air quality benefits could be
achieved by reductions in either NOX emissions or ammonia
emissions. Reductions in secondary ammonium nitrate through
NOX control would achieve the co-benefits identified by the
commenter. Given that there is no atmospheric chemistry connection
between ammonia emissions and ozone production, we agree with the
commenter that ammonia reductions would not achieve the same co-
benefits with respect to ozone that NOX reductions achieve.
Ammonia reductions may, however, achieve other air quality co-benefits
depending on the specifics of the ammonia controls, which are not
explored in the Plan but may be uncovered by additional analysis. In
any case, this issue does not affect our conclusion that ammonia is a
PM2.5 precursor subject to control evaluation for purposes
of the 2006 PM2.5 NAAQS in the SJV.

C. Comments Regarding RACM/RACT and Adopted Control Strategy

    Comment 6: Earthjustice argues that the EPA should disapprove the
Plan's RACM/RACT demonstration because it does not include all
reasonably available control measures. Earthjustice asserts that the
EPA's review of this demonstration in its proposed rule ``does little
more than rubberstamp the District's unsupported assertions'' that all
reasonable controls have been exhausted, and identifies six source
categories for which it claims that existing control measures could
reasonably be strengthened or other reasonable new control measures
have yet to be adopted and implemented.
    Response 6: We disagree with these arguments. Section 107(a) of the
CAA provides states with both authority and primary responsibility for
developing SIPs that meet applicable statutory and regulatory
requirements for attaining, maintaining, and enforcing the NAAQS.
States have discretion in formulating their SIPs, and the EPA is
required to approve a SIP submission that satisfies the applicable
requirements of the Act.\25\
---------------------------------------------------------------------------

    \25\ CAA section 110(k)(3), 42 U.S.C. 7410(k)(3) and 40 CFR
52.02(a); see also Union Elec. Co. v. EPA, 427 U.S. 246, 250 (1976);
Train v. Natural Res. Def. Council, 421 U.S. 60, 79 (1975).
---------------------------------------------------------------------------

    As explained in our proposed rule, the 2012 PM2.5 Plan
discusses the District's process for evaluating potential RACM/RACT in
accordance with the EPA's recommendations in the General Preamble and
describes each of the control measures for sources of direct
PM2.5, NOX, SO2, and ammonia that the
Plan relies on to satisfy the RACM/RACT requirement for the 2006
PM2.5 NAAQS.\26\ For the reasons provided in our proposed
rule and further below, we conclude that the 2012 PM2.5 Plan
provides for the implementation of all RACM/RACT that could reasonably
be implemented in the SJV by the statutory implementation deadline, as
required by CAA sections 172(c) and 189(a)(1)(C).
---------------------------------------------------------------------------

    \26\ 80 FR 1816, 1827-1830.
---------------------------------------------------------------------------

    We note that, as of the date of our proposed action on the 2012
PM2.5 Plan and 2014 Supplement, which published on January
13, 2015, it was not practicable for the state to adopt additional
control measures for implementation by the RACM implementation deadline
under CAA section 189(a)(1)(C), which was December 14, 2013.\27\ The
State and District must, however, include in the Serious area plan for
the 2006 PM2.5 NAAQS, which is due August 21, 2017,
provisions to assure that the best available control measures (BACM)
for the control of PM2.5 and PM2.5 precursors
shall be implemented no later than 4 years after the date the area was
reclassified as a Serious area, i.e., by February 19, 2020.\28\ The
required evaluation of BACM/BACT control measures in the Serious area
plan must address sources of direct PM2.5 and all
PM2.5 precursors, except for any PM2.5
precursor(s) for which the State submits and the EPA approves a
comprehensive precursor demonstration consistent with the requirements
of subpart 4 of part D, title I of the Act. In accordance with the
requirements of CAA section 172(c)(6), the Serious area plan must also
include any additional feasible measures to control emissions of direct
PM2.5 and PM2.5 precursors that are necessary or
appropriate to provide for attainment of the 2006 PM2.5
NAAQS as expeditiously

as practicable and no later than December 31, 2019.\29\
---------------------------------------------------------------------------

    \27\ The SJV area was designated nonattainment for the 2006
PM2.5 NAAQS effective December 14, 2009. 74 FR 58688
(November 13, 2009) and 40 CFR 81.305. Therefore, the statutory
deadline for implementation of RACM in the SJV under CAA section
189(a)(1)(C) for this NAAQS was December 14, 2013.
    \28\ The EPA reclassified the SJV area as a Serious
nonattainment area for the 2006 PM2.5 NAAQS effective
February 19, 2016. 81 FR 2993 (January 20, 2016) (final
reclassification) and 81 FR 42263 (June 29, 2016) (correcting
amendment). Therefore, the statutory deadline for implementation of
BACM in the SJV under CAA section 189(b)(1)(B) for this NAAQS is
February 19, 2020.
    \29\ See EPA, Final Rule, ``Fine Particulate Matter National
Ambient Air Quality Standards: State Implementation Plan
Requirements,'' July 29, 2016 (pre-publication notice) at 40 CFR
51.1010(a)(4)(ii). Although this regulatory text is not yet
effective, it reflects the EPA's interpretation of the statutory
requirements.
---------------------------------------------------------------------------

    We respond below to the specific comments pertaining to the six
source categories highlighted by Earthjustice.
    Comment 6a: Standards for Agricultural Equipment. Earthjustice
asserts that the District's ``replacement of more than 1,000 pieces of
off-road equipment and agricultural equipment'' through implementation
of incentive programs has demonstrated the feasibility of emission
controls on off-road agricultural equipment and argues that CARB has
the ability to create binding, enforceable regulations to reduce
NOX emissions from off-road agricultural equipment to hasten
attainment of the 2006 PM2.5 NAAQS in the SJV.
    Response 6a: To the extent Earthjustice intended to argue that the
replacement of off-road agricultural equipment through incentive
programs implemented in the SJV demonstrates that NOX
controls for such equipment are both technologically and economically
feasible, we disagree.
    Given the commenter did not specify the types and/or sizes of off-
road equipment for which it believes NOX controls are
feasible, we evaluated several types of off-road agricultural equipment
replacement projects funded through the Carl Moyer Memorial Air Quality
Standards Attainment Program in the SJV in recent years to determine
the costs and technical issues associated with such replacements. We
used the SJVUAPCD's ``Annual Demonstration Report'' data sheets for
2013,\30\ 2014,\31\ and 2015,\32\ which the District submitted pursuant
to SJVUAPCD Rule 9610, to determine the cost effectiveness and
technological feasibility of off-road agricultural equipment
replacements. We limited our analysis to projects categorized as ``off-
road'' and as ``vehicle replacements,'' and that included data for
``cost of new equip vehicle'' \33\ and non-zero emission reductions
values reported for NOX and/or particulate matter (PM).\34\
Off-road agricultural equipment encompasses a wide variety of types of
equipment. The 1807 pieces of equipment listed in the data sheets that
we reviewed include: Almond shakers, almond sweepers, backhoes, bale
wagons, balers, bulk carriers, combines, cotton pickers, forage
harvesters, forklifts, harvesters, hay haulers, loaders, silage
baggers, sprayers, swathers, tomato harvesters, tractors, tractor
crawlers, and wheel loaders. Additionally, as seen in Tables 2, 3, and
4 below, the data sheets identify a wide range of equipment horsepower
levels and capital costs of replacing agricultural off-road equipment,
from which the EPA calculated mean and median values and cost-
effectiveness values for NOX controls.\35\
---------------------------------------------------------------------------

    \30\ Available at http://www.valleyair.org/MOP/docs/069610ProjectDataforPublicUNLOCKED-1-30-14.xlsx.
    \31\ Available at http://www.valleyair.org/MOP/docs/9610ProjectDataforPublicUNLOCKED-8-11-14.xlsx.
    \32\ Available at http://www.valleyair.org/MOP/docs/9610ProjectDataforPublic2015.xlsx.
    \33\ We did not evaluate the 125 projects in the 2014 Data Sheet
categorized as ``off-road'' and as ``vehicle replacements'' for
which the Data Sheet identified ``cost retrofit'' instead of ``cost
of new equip vehicle'' values.
    \34\ We did not evaluate the 29 projects in the 2013 Data Sheet
categorized as ``off-road'' and as ``vehicle replacements'' for
which the Data Sheet identified zero NOX and PM emission
reductions.
    \35\ We calculated the cost-effectiveness of NOX
controls by dividing the ``Cost of New Equipment'' values by the
``NOX Lifetime Reduced (tons)'' values for each of the
identified projects to obtain $/ton values.

                             Table 2--Horsepower for Off-Road Agricultural Equipment
----------------------------------------------------------------------------------------------------------------
                                                                                Date of
                                                                                ``Annual
                                                                                Demonstration
                                                                    Horsepower      Project ID     Report'' data
                                                                       (HP)                            sheet
                                                                                identifying
                                                                                project
----------------------------------------------------------------------------------------------------------------
Minimum.........................................................              28       C-21377-A            2014
Maximum.........................................................             653       C-21973-A            2014
Mean............................................................             128  ..............  ..............
Median..........................................................             105  ..............  ..............
----------------------------------------------------------------------------------------------------------------
Source: Minimum and maximum horsepower based on EPA review of SJVUAPCD, ``Annual Demonstration Report'' data
  sheets for 2013, 2014, and 2015. Mean and median values calculated by EPA.

                                Table 3--Cost of Off-Road Agricultural Equipment
----------------------------------------------------------------------------------------------------------------
                                                                                Date of
                                                                                ``Annual
                                                                                Demonstration
                                                                    Cost of new     Project ID     Report'' data
                                                                   equipment ($)                       sheet
                                                                                identifying
                                                                                project
----------------------------------------------------------------------------------------------------------------
Minimum.........................................................       10,031.50       C-22064-A            2014
Maximum.........................................................      685,736.52       C-27498-A            2015
Mean............................................................       82,182.69  ..............  ..............
Median..........................................................       51,212.29  ..............  ..............
----------------------------------------------------------------------------------------------------------------
Source: Minimum and maximum cost based on EPA review of SJVUAPCD, ``Annual Demonstration Report'' data sheets
  for 2013, 2014, and 2015. Mean and median values calculated by EPA.

                 Table 4--Cost Effectiveness of NOX Control for Off-Road Agricultural Equipment
----------------------------------------------------------------------------------------------------------------
                                                                                Date of
                                                                                ``Annual
                                                                       Cost                        Demonstration
                                                                   effectiveness    Project ID     Report'' data
                                                                      ($/ton)                          sheet
                                                                                identifying
                                                                                project
----------------------------------------------------------------------------------------------------------------
Minimum.........................................................        1,141.00         C-8160A            2013
Maximum.........................................................      436,140.00       C-22654-A            2014
Mean............................................................       38,687.61  ..............  ..............
Median..........................................................       18,863.95  ..............  ..............
----------------------------------------------------------------------------------------------------------------
Source: EPA, ``Agricultural Mobile Engine Projects--EPA cost-effectiveness calculations,'' July 21, 2016.

    The significant costs associated with replacing off-road
agricultural equipment in the SJV indicate that replacement of such
equipment without funding assistance generally is not economically
feasible at this time. In addition, the wide variations in the sizes
and uses of such equipment in the SJV and the available control
technologies indicate that replacement of off-road agricultural
equipment in the SJV may not be technically feasible for many types of
equipment. Accordingly, we disagree with Earthjustice's suggestion that
requirements to replace off-road agricultural equipment are required
RACM in the SJV.
    Comment 6b: Fleet Rules. Earthjustice comments that the District
can further reduce emissions from mobile sources by adopting additional
``fleet'' rules to regulate emissions from publicly-owned vehicles.
Earthjustice notes that while the District currently maintains a fleet
rule only for school buses, the South Coast Air Quality Management
District (SCAQMD) has adopted rules for buses; light-, medium-, and
heavy-duty public fleet vehicles; waste collection vehicles; airport
ground transportation such as taxis and shuttles; and street sweepers.
Earthjustice states that the District should implement similar
restrictions on publicly-owned vehicles.
    Response 6b: We disagree with Earthjustice's suggestion that
adoption of additional ``fleet'' rules is necessary to satisfy the
RACM/RACT requirement for the 2006 PM2.5 NAAQS in the SJV.
    As the commenter notes, the SCAQMD has adopted several rules to
encourage public agencies and some private entities to shift to the use
of lower emissions vehicles,\36\ including the following:
---------------------------------------------------------------------------

    \36\ The applicability of these rules was narrowed to exclude
federal fleets and certain private fleets. See http://www.aqmd.gov/docs/default-source/Regulations/Fleet-Rules/fleetruleadvisory-july202005.pdf?sfvrsn=0.

Rule 1186.1 Less-Polluting Street Sweepers, adopted August 18, 2000;
Rule 1191 Clean On-Road Light and Medium Duty Public Fleet Vehicles,
adopted June 16, 2000;
Rule 1192 Clean On-Road Transit Buses, adopted June 16, 2000;
Rule 1193 Clean On-Road Residential and Commercial Refuse Collection
Vehicles, adopted June 16, 2000.
Rule 1194 Commercial Airport Ground Access Vehicles, adopted August
18, 2000;
Rule 1195 Clean On-Road School Buses, adopted April 20, 2001; and
Rule 1196 Clean On-Road Heavy-Duty Public Fleet Vehicles, adopted
October 20, 2000.

    As explained in Appendix C of the 2012 PM2.5 Plan, both
CARB and the SJVUAPCD have adopted fleet rules to reduce emissions from
specific types of on-road vehicle fleets, e.g., CARB's Fleet Rule for
Public Agencies and Utilities, which addresses diesel particulate
matter from vehicle fleets operated by public agencies and utilities,
and SJVUAPCD Rule 9310 (School Bus Fleets), which requires replacement,
retrofit, or repowering of older diesel-fueled school buses.\37\ The
District acknowledges in Appendix C of the Plan that the SCAQMD is
implementing a fleet rule that requires solid waste collection vehicle
fleets to operate entirely on alternative fuel beginning in 2011 but
explains that transitioning a fleet from diesel to alternative fuel can
be costly and may not be economically feasible in the SJV.\38\
Additionally, according to the SJVUAPCD, the emissions benefit
associated with such a transition is minimal given the stringent
particulate matter requirements under CARB's Fleet Rule for Public
Agencies, and the relatively small difference in NOX
emissions, if any, between diesel and alternative fuel vehicles.\39\
The commenter provides no information to support a claim that the
SJVUAPCD could reasonably have adopted and implemented identical or
similar rules in the SJV prior to the RACM/RACT implementation
deadline, which was December 14, 2013. We note that none of the SCAQMD
fleet rules identified above has been submitted for approved into the
California SIP.
---------------------------------------------------------------------------

    \37\ 2012 PM2.5 Plan, Appendix C at C-7 to C-11.
    \38\ Id. at C-8, C-9 (noting that ``establishing new alternative
fuel infrastructure can cost millions of dollars and alternative
fuel SWCVs generally cost $25,000 more than diesel'').
    \39\ Id.
---------------------------------------------------------------------------

    Comment 6c: Indirect Source Review (ISR) Improvements. Earthjustice
comments that the District can obtain additional emissions reductions
by expanding the applicability of its ISR rule, which Earthjustice
notes was last updated in 2005. Earthjustice suggests that the District
could eliminate provisions that allow businesses to mitigate their
emissions by paying fees (or establish a minimum emission level for
when a business may use this option), add limits for PM2.5
emissions, and require projects to achieve greater emissions
reductions.
    Response 6c: We disagree with the commenter's suggestion that
revisions to SJVUAPCD Rule 9510 (``Indirect Source Review'') are
necessary to satisfy RACM requirements for the 2006 PM2.5
NAAQS in the SJV.
    SJVUAPCD Rule 9510, as adopted December 15, 2005, requires
applicants for development projects of certain sizes and certain
transportation or transit projects to reduce NOX and
particulate matter (PM) emissions from the development and use of such
projects through various on-site mitigation measures or payment of fees
to fund off-site emission reduction projects. The EPA approved SJVUAPCD
Rule 9510 into the California SIP at 76 FR 26609 (May 9, 2011) but
explained in that action that the EPA and the District were acting
under section 110(a)(5) of the CAA. Under that section, the EPA is
prohibited from requiring states to include ISR programs in SIPs.
Specifically, CAA section 110(a)(5)(A)(i) states that any State may
include in a State implementation plan, but the Administrator may not
require as a condition of approval of such plan under this section, any
indirect source review program. Section 110(a)(5)(A)(i) also states
that the Administrator may approve and enforce, as part of an

applicable implementation plan, an indirect source review program which
the State chooses to adopt and submit as part of its plan.\40\ Because
SJVUAPCD Rule 9510 constitutes an ISR program, the EPA may not require
the District to consider revisions to this rule, for RACM purposes or
otherwise.
---------------------------------------------------------------------------

    \40\ CAA section 110(a)(5)(A)(i).
---------------------------------------------------------------------------

    Comment 6d: Fireplace Rule Improvements. Earthjustice comments that
the District could reduce direct PM2.5 emissions by making
SJVUAPCD Rule 4901 (Wood Burning Fireplaces and Wood Burning Heaters)
more stringent. Earthjustice notes that this rule was updated in 2014,
but argues that this update did not make the rule ``as stringent as it
reasonably could,'' because it allows cleaner classes of wood-burning
heaters to be used at ambient concentrations up to 65 microgram per
meter cubed ([mu]g/m\3\). Earthjustice argues that a more appropriate
threshold would be 35 [mu]g/m\3\, the attainment level for the 2006
PM2.5 NAAQS, and that the District should amend the rule to
disallow use of these heaters when concentrations are expected to
exceed this level. Earthjustice asserts that the District ``should
prioritize making the rule as protective as possible'' to reduce direct
PM2.5 emissions.
    Response 6d: We disagree with the commenter's suggestion that
revisions to SJVUAPCD Rule 4901 are necessary to satisfy RACM
requirements for the 2006 PM2.5 NAAQS in the SJV.
    Consistent with the District's rule amendment commitments in the
2012 PM2.5 Plan,\41\ the SJVUAPCD amended Rule 4901 on
September 18, 2014, and CARB submitted the amended rule to the EPA for
SIP action on November 6, 2014.\42\ On August 15, 2016, Acting Regional
Administrator Alexis Strauss signed a notice of final rulemaking to
approve SJVUAPCD Rule 4901, as amended September 18, 2014, as meeting
applicable CAA requirements and implementing RACM/RACT for
PM2.5 emissions from wood burning devices.\43\
---------------------------------------------------------------------------

    \41\ 80 FR 1816, 1832 at Table 3 (January 13, 2015); see also
2012 PM2.5 Plan, Chapter 5 (``Control Strategy''),
Section 5.3 (``New Control Measures''), p. 5-21 to 5-22.
    \42\ 80 FR 58637 (September 30, 2015).
    \43\ EPA, Final Rule, ``Approval of California Air Plan
Revisions, San Joaquin Valley Unified Air Pollution Control
District,'' August 15, 2016 (pre-publication notice).
---------------------------------------------------------------------------

    Comment 6e: Interim Charbroiling Regulations. Earthjustice argues
that the District has delayed updating its charbroiler rule even though
the Bay Area Air Quality Management District (BAAQMD) has already
implemented regulations on under-fired charbroilers. Earthjustice
points out that in 2012, it and other organizations asked the District
to update the rule sooner, to include controls similar to those in the
Bay Area and to follow up with another rule update when new
technologies are reasonably available.
    Response 6e: We disagree with the commenter's suggestion that
SJVUAPCD Rule 4692 (Commercial Charbroiling) fails to satisfy RACM
requirements for the 2006 PM2.5 NAAQS in the SJV and that
control measures for under-fired charbroilers are necessary to satisfy
these requirements.
    SJVUAPCD Rule 4692, as amended September 17, 2009, applies to
chain-driven charbroilers used in commercial meat cooking and requires
a catalytic oxidizer or alternative controls with a control efficiency
of at least 83 percent for PM10 emissions and 86 percent for
VOC emissions. The rule exempts charbroilers used to cook less than 400
pounds of meat in a calendar week, and other limited-use charbroilers
that do not exceed weekly and rolling 12-month maximum use limits and
that have not previously been required to comply with the rule's
control requirements. It does not regulate under-fired
charbroilers.\44\
---------------------------------------------------------------------------

    \44\ SJVUAPCD Rule 4692 (amended September 17, 2009), sections
4.1, 5.1, and 5.2.
---------------------------------------------------------------------------

    The BAAQMD is the only air district that we are aware of that has
adopted regulations to reduce emissions from under-fired charbroilers.
BAAQMD Regulation 6, Rule 2 (Commercial Cooking Equipment),\45\ applies
to chain-driven charbroilers in restaurants that purchase 500 pounds or
more of beef per week, and to under-fired charbroilers in restaurants
that purchase 1,000 pounds or more of beef per week. The rule requires
these restaurants to control emissions using a certified control device
and to register charbroilers and associated emission control devices
with the BAAQMD. The rule exempts low-utilized charbroilers, including
under-fired charbroilers used to grill less than 800 pounds of beef per
week.\46\
---------------------------------------------------------------------------

    \45\ BAAQMD Regulation 6, Rule 2 (adopted December 5, 2007),
available at http://www.arb.ca.gov/DRDB/BA/CURHTML/R6-2.PDF.
    \46\ BAAQMD Regulation 6, Rule 2 (adopted December 5, 2007),
sections 6-2-102, 6-2-110, 6-2-111, 6-2-300, and 6-2-400.
---------------------------------------------------------------------------

    According to BAAQMD planning and compliance staff, the control
requirements in Regulation 6, Rule 2 for under-fired charbroilers have
not yet been implemented in practice.\47\ BAAQMD staff noted that no
under-fired charbroilers in the Bay Area are currently registered
pursuant to Regulation 6 Rule 2, indicating that restaurants in the Bay
Area are operating below the thresholds that trigger the requirements.
In addition, the BAAQMD's most recent inspections found that
restaurants were below these thresholds.\48\ Significantly, the BAAQMD
has not yet certified any emission control devices for under-fired
charbroilers. BAAQMD staff explained that they are waiting to receive
and review final test reports from the University of California at
Riverside, Center for Environmental Research and Technology (CE-CERT)
before making certifications.\49\
---------------------------------------------------------------------------

    \47\ Email dated April 4, 2016, from Virginia Lau of the BAAQMD
to Stanley Tong of EPA Region 9, regarding ``Update on Bay Area
charbroiler registration.''
    \48\ BAAQMD staff noted that these inspections occurred during a
period of economic recession, and that conditions may have changed
since. Email dated April 4, 2016, from Virginia Lau of the BAAQMD to
Stanley Tong of EPA Region 9, regarding ``Update on Bay Area
charbroiler registration.''
    \49\ CE-CERT informed SCAQMD that charbroiler testing will be
delayed for up to four months due to fire suppression system
upgrades in its test kitchen. Email dated March 16, 2016 from
Michael Laybourn of the SCAQMD to Stanley Tong of EPA Region 9,
regarding ``Charbroiler Testing.''
---------------------------------------------------------------------------

    The SJVUAPCD's 2012 PM2.5 Plan summarizes PM control
technology for under-fired charbroilers.\50\ It finds that catalytic
oxidizers are not effective for under-fired charbroilers because the
exhaust from these devices loses too much heat before it reaches the
catalyst. The Plan lists High Efficiency Particulate-Arresting (HEPA)
filtration, Electrostatic Precipitators (ESP), and Wet Scrubbers as
potentially more effective control technology for under-fired
charbroilers, but notes that the SJVUAPCD found these technologies were
``unproven and extremely costly'' when it amended SJVUAPCD Rule 4692 in
2009. During that amendment process, the District found that the
initial costs for these controls ranged from $37,500 to $104,000, which
results in a cost of approximately $58,200 per ton of PM2.5
reduced. The District has estimated the total costs of installing,
operating, and maintaining these controls to be as much as 20 to 30
percent of a restaurant's net profits.\51\ As a result, the District
decided not to adopt regulations for under-fired charbroilers as part
of its rule amendments in 2009. We note that the Plan contains the
District Governing Board's commitment to adopt control

measures for under-fired charbroilers in 2016.\52\
---------------------------------------------------------------------------

    \50\ 2012 PM2.5 Plan, Appendix D at D-111 to D-117.
    \51\ Action Summary Minutes, San Joaquin Unified Air Pollution
Control District, Governing Board, August 20, 2009, page 7,
available at http://www.valleyair.org/Board_meetings/GB/agenda_minutes/Minutes/2009/Minutes_GB_2009_Aug.pdf.
    \52\ 2012 PM2.5 Plan, Chapter 5 (``Control
Strategy''), Section 5.3 (``New Control Measures''), p. 5-21 to 5-
22, and SJVUAPCD Governing Board Resolution 2012-12-19 (December 20,
2012), page 4; see also 80 FR 1816, 1832 at Table 3 (January 13,
2015).
---------------------------------------------------------------------------

    A study conducted by the University of California at Berkeley \53\
arrives at a similar conclusion regarding the cost of PM controls for
under-fired charbroilers. Using 2007 economic census data, the study
estimates the average annual profit of restaurants in the SJVUAPCD area
to be $23,000-$47,000 per establishment, for a profit margin of 3.5-5.9
percent. Similarly, the study estimates the annual profit for average
large restaurants (i.e., restaurants averaging 60 employees) to be
approximately $110,000. The study also finds that the average capital
cost for particulate matter (PM) emission controls such as an ESP, HEPA
filtration, or wet scrubber can range from approximately $38,750 to
$50,000, with average annualized costs for installation and operation
of $11,000-$15,000. The study calculates the total costs associated
with these controls to be approximately 10-14 percent of an average
large restaurant's profits. The study states that ``[t]hese figures may
appear modest . . . given that installing control technologies would
amount to only a tenth of [large] restaurant profits. However . . .
this figure is several times larger than the case of successful chain-
driven charbroiler regulations, where the cost of installing catalytic
oxidizers represented just 2.2 percent of average restaurant profits.''
\54\ The study notes that its annualized cost estimates parallel
SJVUAPCD's estimates, even though the data were drawn from different
sources.\55\
---------------------------------------------------------------------------

    \53\ Bellisario, J., Mandel, B., Perkins, J., Ruan, Y.,
``Regulating Emissions from Under-fired Charbroilers,'' University
of California, Berkeley, Goldman School of Public Policy, May 2012.
    \54\ Id. at p. 24.
    \55\ Id. at p. 24.
---------------------------------------------------------------------------

    We anticipate the CE-CERT research report will help clarify the
cost effectiveness of various under-fired charbroiler emission control
technologies, some of which are prototypes, which will supplement the
earlier Berkeley study to help inform more effective rule
development.\56\ Additionally, the District is currently undertaking
efforts that may yield additional information relevant to whether
additional controls for charbroilers would be appropriate and feasible
in the SJV. To help study the technological feasibility and
effectiveness of potential control technologies, the SJVUAPCD Governing
Board approved $750,000 for its Restaurant Charbroiler Technology
Partnership program to fund PM control technology demonstration
projects for under-fired charbroilers at Valley restaurants.\57\ The
District's funding would include the full purchase cost, installation,
operation, maintenance, and other costs such as modifications to
existing system configurations and structural reinforcements, and will
help evaluate control systems operations, maintenance, and labor costs
in the field. Completion of these research efforts will allow
regulatory agencies to evaluate overall PM reduction strategies, which
will help in designing economically and technically feasible
regulations that can achieve the necessary PM reductions.
---------------------------------------------------------------------------

    \56\ The SCAQMD, BAAQMD, SJVUAPCD, and EPA Region 9 are part of
a workgroup to provide input on the CE-CERT under-fired charbroiler
testing research.
    \57\ See Restaurant Charbroiler Technology Partnership,
available at http://valleyair.org/grants/rctp.htm, and
``Charbroilers Come Under San Joaquin Valley Air District's
Microscope,'' The Modesto Bee, December 27, 2015, http://www.recordnet.com/article/20160101/NEWS/160109993.
---------------------------------------------------------------------------

    Based on these evaluations, we find that SJVUAPCD Rule 4692
implements RACM/RACT for charbroilers for purposes of the 2006
PM2.5 NAAQS in the SJV.
    Comment 6f: Performance Standards for Flares. Earthjustice comments
that the District could strengthen Rule 4311 (Flares) by adopting a
performance-based standard for flaring. Earthjustice states that the
District should assess the strength of its rule against rules in other
areas with high oil and gas production, and suggests North Dakota as an
example. As explained by Earthjustice, North Dakota requires operators
to meet targets for natural gas capture that increase over time from 74
percent in 2014 to an expected 90 percent by 2020, and allows state
regulators to restrict oil production if the operators do not meet
these targets. Earthjustice says that the District could ``borrow
from'' this approach by assessing the percentage of natural gas flared
in the San Joaquin Valley and developing regulations to reduce flaring.
    Response 6f: We disagree with the commenter's suggestion that
revisions to SJVUAPCD Rule 4311 (Flares) are necessary to satisfy RACM
requirements for the 2006 PM2.5 NAAQS in the SJV.
    SJVUAPCD Rule 4311, as amended June 18, 2009, limits VOC,
NOX, and sulfur oxides (SOX) emissions from
industrial operations involving the use of flares. The rule includes
general requirements for combusting waste gases, emission standards for
ground-level enclosed flares, and performance targets for petroleum
refinery flares. Operators of refinery flares and flares with capacity
greater than 5.0 MMBtu/hour are required to submit flare minimization
plans (FMPs) containing information such as detailed process diagrams,
descriptions of upstream equipment, and evaluations of preventive
measures to reduce flaring.\58\ The rule prohibits flaring unless it is
done consistently with a District-approved FMP.\59\ Additionally, the
rule includes monitoring, recordkeeping, and reporting requirements,
including a requirement for operators to investigate and report flaring
events.\60\
---------------------------------------------------------------------------

    \58\ SJVUAPCD Rule 4311 (adopted June 18, 2009), sections 5.8
and 6.5.
    \59\ Id.
    \60\ Id. at sections 6.1 and 6.2.
---------------------------------------------------------------------------

    As the commenter notes, North Dakota has adopted rules governing
flaring in the oil and gas industry, through provisions of the North
Dakota Century Code and an Order issued by the Industrial Commission of
North Dakota. Section 38-08-06.4 of the North Dakota Century Code
allows oil wells to flare gas during the first year of production, and
thereafter requires wells either to be capped or to be equipped with
approved capture or control measures that, at a minimum, reduce flared
gas by at least 60 percent, unless the operator can demonstrate that
such measures are not economically feasible.\61\ Industrial Commission
Order 24665 adopts tiered gas capture goals that include a target of 74
percent capture in 2014 and an end target of 90 percent capture in
2020.\62\
---------------------------------------------------------------------------

    \61\ North Dakota Century Code, Section 38-08-06.4, as effective
January 2016.
    \62\ State of North Dakota, Industrial Commission Order No.
24665 (dated July 1, 2014).
---------------------------------------------------------------------------

    The SJVUAPCD's 2012 PM2.5 Plan states that Rule 4311 is
more stringent than flare rules in other California air districts.
Appendix D of the Plan compares Rule 4311 to SCAQMD Rule 1118, BAAQMD
Rules 12-11 and 12-12, and Santa Barbara County Air Pollution Control
District (SBCAPCD) Rule 359.\63\ According to the District, these rules
contain requirements for FMPs and monitoring, recordkeeping, and
reporting provisions similar to those in SJVUAPCD Rule 4311, and
emission standards for ground-level enclosed flares, but Rule 4311
applies to a wider range of operations and does not include certain
exemptions present in the other districts' rules.\64\ The District

also states that the Sacramento Metropolitan Air Quality Management
District (SMAQMD) and Ventura County Air Pollution Control District
(VCAPCD) do not have specific prohibitory rules for flares.\65\
---------------------------------------------------------------------------

    \63\ The 2012 PM2.5 Plan mistakenly identifies the
Santa Barbara rule as ``Rule 4359.'' 2012 PM2.5 Plan,
Appendix D at D-71.
    \64\ 2012 PM2.5 Plan, Appendix D at D-71.
    \65\ Id. The VCAPCD does not have a specific flaring rule, but
VACPCD Rule 54, ``Sulfur Compounds'' includes requirements for
flaring events, including FMPs. The District's ``2015 Plan for the
1997 PM2.5 Standard'' (``2015 PM2.5 Plan'')
includes this rule in a table comparing Rule 4311 to other
California air district rules, and states that SJVUAPCD Rule 4311 is
at least as stringent. 2015 PM2.5 Plan, Appendix C: BACM
and MSM for Stationary and Area Sources, at page C-79.
---------------------------------------------------------------------------

    The District has addressed the North Dakota Century Code and the
Industrial Commission Order in Appendix C of the ``2015 Plan for the
1997 PM2.5 Standard'' (hereafter ``2015 PM2.5
Plan'').\66\ There, the District concludes that SJVUAPCD Rule 4311 is
more stringent than the North Dakota rule. Among its findings in
support of this conclusion, the District notes that Rule 4311 applies
to a broader range of sources and achieves a higher percentage of gas
capture.\67\ Appendix C of the 2015 PM2.5 Plan also
discusses SBCAPCD Rule 359, which includes a performance standard for
gas volume.\68\ The District concludes that Rule 4311 is more stringent
than this rule, citing reasons that include Rule 4311's applicability
to a broader range of sources, fewer exemptions, and greater percentage
gas capture.\69\
---------------------------------------------------------------------------

    \66\ 2015 PM2.5 Plan, Appendix C: BACM and MSM for
Stationary and Area Sources, at page C-81.
    \67\ In its comparison of Rule 4311 to the North Dakota
provisions, the 2015 PM2.5 Plan states that Rule 4311
``requires 95% capture and treatment of produced gas.'' 2015
PM2.5 Plan, Appendix C: BACM and MSM for Stationary and
Area Sources, at page C-82. We interpret this to mean that the rule
achieves at least 95 percent capture in practice, as demonstrated at
Table C-11 of the Plan. 2015 PM2.5 Plan, Appendix C: BACM
and MSM for Stationary and Area Sources, at page C-80. See email
dated May 20, 2016, from Sheraz Gill of the SJVUAPCD to Andrew
Steckel of EPA Region 9, regarding Small flares question.
    \68\ 2015 PM2.5 Plan, Appendix C: BACM and MSM for
Stationary and Area Sources, at pp. C-79 to C-81.
    \69\ Id. at C-81.
---------------------------------------------------------------------------

    We agree with the District's analysis and conclusion that SJVUAPCD
Rule 4311 is at least as stringent as the rules adopted by the other
California air districts and the requirements in place in North Dakota.
Therefore, we disagree with the commenter's assertion that a
performance-based standard like North Dakota's would be more protective
than Rule 4311. While Rule 4311 does not set performance targets for
reducing flared gas, information in the record indicates that it
achieves emission reductions greater than those targets. Table C-11 of
the 2015 PM2.5 Plan shows that the percentage of gas flared
in the SJV in the years between 2009 and 2013 has never exceeded 5
percent.\70\ This analysis addresses the commenter's suggestion that
the District should assess the percentage of natural gas flared in the
District, and it indicates that adoption of requirements like North
Dakota's would not reduce emissions from flaring in the SJV.
---------------------------------------------------------------------------

    \70\ 2015 PM2.5 Plan, Appendix C: BACM and MSM for
Stationary and Area Sources, at page C-79. SJVUAPCD staff confirmed
that the data in this table comes from the annual emissions
inventory reports submitted by sources to the District. Email dated
April 27, 2016, from Sheraz Gill of the SJVUAPCD to Andrew Steckel
of EPA Region 9, regarding SJV flares data inquiry.
---------------------------------------------------------------------------

    Based on this assessment, we find that SJVUAPCD Rule 4311
represents RACT for flaring operations in the SJV, and that the
alternatives suggested by the commenter would not achieve additional
emission reductions.
    Comment 7: Earthjustice comments that the RACM/RACT analysis in the
Plan does not include reasonable controls for condensable emissions,
and that the EPA must therefore disapprove the RACM/RACT demonstration.
Earthjustice states that 40 CFR 51.1002(c) requires agencies to set
controls for condensable emissions beginning January 1, 2011, and
quotes the EPA's prior statement at 72 FR 20586, 20652 that ``[w]e
expect States to address the control of direct PM2.5
emissions, including condensables [sic] \71\ with any new actions taken
after January 1, 2011.''
---------------------------------------------------------------------------

    \71\ The Federal Register notice uses the term ``condensable
PM.''
---------------------------------------------------------------------------

    Response 7: We agree with Earthjustice's statement that the
transition period under 40 CFR 51.1002(c) (as effective May 29, 2007)
\72\ allowing state and local agencies to submit plans that do not
address condensable emissions ended on January 1, 2011. We disagree,
however, with the claim that the EPA must disapprove the RACM/RACT
demonstration in the Plan for failure to assess controls on condensable
PM2.5 emissions.
---------------------------------------------------------------------------

    \72\ 72 FR 20586 (April 25, 2007). The EPA's recent final rule
to implement the PM2.5 NAAQS also requires that emission
limitations for PM2.5 sources address condensable
PM2.5. See EPA, Final Rule, ``Fine Particulate Matter
National Ambient Air Quality Standards: State Implementation Plan
Requirements,'' July 29, 2016 (pre-publication notice) at p. 567
(requiring at 40 CFR 51.1009(c) that, for new or revised source
emissions limitations on sources of direct PM2.5
emissions, states apply such emissions limitations either to the
total of the filterable plus condensable fractions of direct
PM2.5, or to filterable PM2.5 and condensable
PM2.5 separately).
---------------------------------------------------------------------------

    EPA regulations at 40 CFR 51.1002(c), as effective May 29, 2007,
provide that, after January 1, 2011, for purposes of establishing
emissions limits to satisfy requirements for RFP and reasonably
available control measures/reasonably available control technology
(RACM/RACT), states must establish such limits taking into
consideration the condensable fraction of direct PM2.5
emissions. Because direct PM2.5 is comprised of both
filterable PM2.5 and condensable PM2.5,\73\ the
EPA has explained that both the emissions inventories underlying a
PM2.5 attainment plan and any emission limits for sources of
direct PM2.5 in the control strategy must take into
consideration the condensable fraction of PM2.5
emissions.\74\ As the EPA stated in the July 29, 2016 final rule to
implement the PM2.5 NAAQS, it is particularly important to
ensure that both the filterable and condensable components of direct
PM2.5 emissions are accurately represented in the base year
emissions inventory underlying a RACM/RACT control analysis.\75\
---------------------------------------------------------------------------

    \73\ Certain commercial or industrial activities involving high
temperature processes (e.g., fuel combustion, metal processing, and
cooking operations) emit gaseous pollutants into the ambient air
which rapidly condense into particle form. These ``condensable''
particulate matter emissions exist almost entirely in the 2.5 or
less micron range and can consist of organic material, sulfuric acid
and metals. 80 FR 15340, 15343 at n. 7 (March 23, 2015); see also 72
FR 20586, 20651 (April 25, 2007).
    \74\ See, e.g., 80 FR 15340, 15412 (March 23, 2015) (discussing
requirement to address condensable PM2.5 in base year
emissions inventory and related SIP control strategies).
    \75\ See EPA, Final Rule, ``Fine Particulate Matter National
Ambient Air Quality Standards: State Implementation Plan
Requirements,'' July 29, 2016 (pre-publication notice) at pp. 66-77,
90-104 and 139-140 (discussing requirements to include condensable
PM2.5 in base year emissions inventories and in RACM/RACT
control evaluations); see also 80 FR 15340 at 15378, 15412.
---------------------------------------------------------------------------

    Chapter 4 of the 2012 PM2.5 Plan contains a brief
discussion of the District's approach to condensable PM2.5
emissions and states that condensable particulates are included in the
District's total emissions inventory for direct PM2.5.\76\
The base year inventory for direct PM2.5 emissions is
provided in Appendix B of the 2012 PM2.5 Plan and includes
condensable emissions. Specifically, the PM2.5 emissions
inventory for commercial cooking operations incorporates emission
factors from a source testing study that collected both filterable and
condensable particulate matter (PM).\77\

Similarly, the SJVUAPCD's PM2.5 emission factors for natural
gas fired boilers, turbines and engines in the manufacturing and
industrial category are based on the EPA's AP-42 emission factors,
which include both filterable and condensable PM.\78\ Also, PM in the
emissions inventory from biomass boilers and natural gas turbines for
the electric utilities sector is based on PM10 testing
required by operating permits and includes both filterable and
condensable PM.\79\ According to the emissions inventories in the 2012
PM2.5 Plan, approximately 38 percent of the 2007 direct
PM2.5 inventory for stationary and area sources comes from
fugitive dust and farming, emission sources that generally do not
produce condensable PM emissions. Stationary source combustion
processes that emit condensable PM, such as electric utilities,
commercial cooking operations and glass melting furnaces, account for
approximately 13.5 percent of the 2007 PM2.5 inventory for
stationary and area sources. Residential fuel combustion, fires, and
managed burning activities account for 44 percent of the stationary and
area source inventory, and miscellaneous industrial processes make up
the remainder of the non-mobile source inventory.\80\
---------------------------------------------------------------------------

    \76\ See 2012 PM2.5 Plan at p. 4-22.
    \77\ See ``2006 Area Source Emissions Inventory Methodology
690--Commercial Cooking Operations,'' available at http://www.valleyair.org/Air_Quality_Plans/EmissionsMethods/MethodForms/Current/CommercialCooking2006.pdf. See also Welch, W.A. and Norbeck,
J.M., 1998, ``Development of Emission Test Methods and Emission
Factors for Various Commercial Cooking Operations,'' TO-98-14-3 and
email dated May 20, 2016, from W. Welch of the SCAQMD to Stanley
Tong of USEPA, RE: Development of PM Charbroiling Emission Factors
using SC 5.1 (confirming that tests were performed using SCAQMD
Method 5.1 which includes both filterable and condensable PM).
    \78\ SJVUAPCD. ``2006 Area Source Emissions Inventory
Methodology 050--Industrial Natural Gas Combustion'' at p. 3
(identifying emission factors are based on the EPA's AP-42 chapters
1.4 and 3.2, which include filterable and condensable PM).
    \79\ Email dated May 18, 2016, from Chay Thao of the SJVUAPCD to
Stanley Tong of EPA Region 9, regarding ``Gas Turbine PM source
testing condensible''; see also SJVUAPCD, Notice of Final Action,
Minor Title V Permit Modification, District Facility #C-14 (April
26, 2012), permit condition 21, available at https://
yosemite.epa.gov/R9/air/EPSS.NSF/0201370ee436adf08825653000726dc1/
e76e9625e609621088257a0e00535d9c/$FILE/Public%20Notice%20Pkg.pdf and
SJVUAPCD, Notice of Final Action, Revised Final Determination of
Compliance, Project Number: N-1113502 (January 18, 2012), permit
condition 51, available at https://yosemite.epa.gov/R9/air/EPSS.NSF/
0201370ee436adf08825653000726dc1/5f867ce070483067882579c300793cbe/
$FILE/Public%20Notice%20Package.pdf.
    \80\ 2012 PM2.5 Plan, Appendix B at B-3.
---------------------------------------------------------------------------

    The 2012 PM2.5 Plan relies on several SJVUAPCD rules
regulating direct PM emissions as part of the PM2.5 control
strategy, including Rule 4692 (Commercial Charbroiling, amended
September 17, 2009), Rule 4103 (Open Burning, amended April 15, 2010),
Rule 4354 (Glass Melting Furnaces, amended May 19, 2011), and Rule 4901
(Wood Burning Fireplaces and Wood Burning Heaters, amended September
18, 2014).\81\ Of the SJVUAPCD rules that control direct PM emissions,
only two establish emission limits for PM: Rule 4692 and Rule 4354.
Both of these rules contain control requirements that apply to
condensable PM and require sources to use test methods that measure
condensable PM.
---------------------------------------------------------------------------

    \81\ 81 FR 6936 at 6951-52, Table 3 (February 9, 2016).
---------------------------------------------------------------------------

    Specifically, section 5.2 of SJVUAPCD Rule 4692 requires that each
chain-driven charbroiler be equipped and operated with a catalytic
oxidizer that has a control efficiency of at least 83 percent for
PM10 emissions, and section 6.5.1 of the rule requires
testing in accordance with the ``South Coast Air Quality Management
District's Protocol,'' which requires measurement of both condensable
and filterable PM in accordance with SCAQMD Test Method 5.1.\82\
SJVUAPCD Rule 4692 defines PM10 as defined in SJVUAPCD Rule
1020 and states that ``[f]or purposes of determining control
efficiency, all particulate collected using the test method specified
in Section 6.5 shall be considered PM10.'' \83\ Because
section 6.5 of SJVUAPCD Rule 4692 requires measurement of both
condensable and filterable PM, both condensable and filterable PM are
considered PM10 under the rule.\84\ Similarly, section 5.4
of SJVUAPCD Rule 4354 establishes emission limits for PM10,
also defined as in SJVUAPCD Rule 1020,\85\ and states that ``total
PM10 includes both filterable PM10 and
condensable PM10.'' Section 6.5.9 of SJVUAPCD Rule 4354
requires testing for condensable PM emissions using EPA Method 202.\86\
No other SIP control measure in the RACM/RACT demonstrations in the
2012 PM2.5 Plan establishes direct PM emission limitations.
---------------------------------------------------------------------------

    \82\ See SCAQMD Protocol, Determination of Particulate and
Volatile Organic Compound Emissions From Restaurant Operations,
November 14, 1997, available at http://yosemite.epa.gov/R9/
R9Testmethod.nsf/0/3D4DEB4D21AB4AAF882570AD005DFF69/$file/
SC%20Rest%20emiss.pdf and SCAQMD Test Method 5.1, Determination of
Particulate Matter Emissions From Stationary Sources Using a Wet
Impingement Train, March 1989, available at http://www.aqmd.gov/docs/default-source/laboratory-procedures/methods-procedures/stm-005-1.pdf?sfvrsn=2.
    \83\ SJVUAPCD Rule 4692 (amended September 17, 2009), section
3.6, defining PM10 ``as defined in Rule 1020
(Definitions).'' SJVUAPCD Rule 1020 defines ``particulate matter''
as ``any material except uncombined water, which exists in a finely
divided form as a liquid or solid at standard conditions,'' and
defines ``PM-10'' as ``particulate matter with an aerodynamic
diameter smaller than or equal to a nominal ten (10) microns as
measured by the applicable state and federal reference test
methods.'' SJVUAPCD Rule 1020 (amended February 21, 2013), sections
3.32 and 3.36, approved at 79 FR 59433 (October 2, 2014).
    \84\ Welch, W.A. and Norbeck, J.M., 1998, ``Development of
Emission Test Methods and Emission Factors for Various Commercial
Cooking Operations,'' TO-98-14-3 (indicating that the majority of PM
emitted from commercial cooking operations is less than 2.5
microns).
    \85\ See SJVUAPCD Rule 4354 (amended May 19, 2011), section
3.30, defining PM10 ``as defined in Rule 1020
(Definitions).'' SJVUAPCD Rule 1020 defines ``particulate matter''
as ``any material except uncombined water, which exists in a finely
divided form as a liquid or solid at standard conditions,'' and
defines ``PM10'' as ``particulate matter with an
aerodynamic diameter smaller than or equal to a nominal ten (10)
microns as measured by the applicable state and federal reference
test methods.'' SJVUAPCD Rule 1020 (amended February 21, 2013),
sections 3.32 and 3.36, approved at 79 FR 59433 (October 2, 2014).
    \86\ 75 FR 80118 (December 21, 2010).
---------------------------------------------------------------------------

    We therefore find that the 2012 PM2.5 Plan adequately
addresses the condensable fraction of direct PM2.5 both in
the base year emissions inventory and in the SIP control strategy.
    Comment 8: Earthjustice argues that the EPA must disapprove the
ammonia RACM/RACT demonstration because the District has not
demonstrated that it has adopted all reasonably available control
measures. According to Earthjustice, the Plan ``includes no analysis of
how Rules 4565, 4566, and 4570 actually control ammonia emissions,''
and the District's ammonia RACM/RACT demonstration ``is little more
than the District's rationalizations for not adopting reasonable
controls'' (emphasis in comment). Earthjustice says that the EPA has
proposed to excuse the Plan's failure to analyze ammonia controls
``because it was submitted too soon after the decision in NRDC for the
District to have incorporated a full analysis of ammonia controls into
the Plan.'' Earthjustice asserts that this consideration ``provides no
basis for finding that the statutory requirements have been met.''
    Response 8: We disagree with Earthjustice's assertion that the EPA
must disapprove the ammonia RACM/RACT demonstration in the Plan. As we
explained in our proposed rule, the 2014 Supplement contains a
discussion of three SIP-approved District rules that regulate VOCs but
also have the effect of reducing ammonia emissions in the SJV, as well
as ammonia control measures implemented elsewhere that the District
evaluated for technical and economic feasibility.\87\ These analyses,
which the EPA has developed further below, demonstrate that SJVUAPCD
Rule 4565, Rule 4566, and Rule 4570 reduce ammonia emissions from
confined animal facilities (CAFs) and composting operations in the SJV,
which together account for

approximately 76 percent of the District's estimates of total 2015
ammonia emissions in the SJV.\88\ We find these evaluations sufficient
to demonstrate that the District has adopted RACM/RACT for ammonia
emissions for purposes of the 2006 PM2.5 NAAQS in the SJV.
---------------------------------------------------------------------------

    \87\ 80 FR 1816 at 1827-1830 (referencing 2014 Supplement at
Attachment A).
    \88\ 2012 PM2.5 Plan, Appendix B at B-17 and 2014
Supplement at Attachment A, p. A-1 (indicating that ``farming
operations'' account for 239.2 tpd of ammonia emission and that
``waste disposal,'' which includes composting solid waste
operations, accounts for 20.5 tpd of ammonia emissions in 2015, from
a total 2015 ammonia inventory of 340.7 tpd).
---------------------------------------------------------------------------

    SJVUAPCD Rule 4565 (Biosolids, Animal Manure, and Poultry Litter
Operations), as adopted March 15, 2007, requires that each operator of
a composting/co-composting facility with a throughput of at least
100,000 wet tons per year conduct all active or curing composting
either in aerated static pile(s) vented to an emission control device
with a VOC control efficiency of at least 80 percent by weight, or in
an in-vessel composting system vented to an emission control device
with a VOC control efficiency of at least 80 percent by weight.\89\
Alternatively, the operator may implement an ``alternative Class Two
mitigation measure'' that is determined by the SJVUAPCD Air Pollution
Control Officer (APCO) and the EPA to achieve equivalent VOC emission
reductions.\90\ According to the District's staff report for SJVUAPCD
Rule 4565, the most commonly used VOC emission control devices at
composting facilities are biofilters, which are used at over twenty
composting facilities in the U.S. and at least five composting
facilities in California.\91\ Biofilters reduce both VOC and ammonia
emissions by oxidizing VOC to carbon dioxide and water and degrading
ammonia emissions into nitrate.\92\ For operators that use a biofilter
as an emission control device, SJVUAPCD Rule 4565 contains detailed
requirements for regularly maintaining, monitoring, and testing the
biofilter.\93\
---------------------------------------------------------------------------

    \89\ SJVUAPCD Rule 4565 (adopted March 15, 2007), section 5.3.3
(requiring implementation of at least one ``Class Two mitigation
measure''); see also 2014 Supplement at Attachment A, p. A-36 to A-
39.
    \90\ SJVUAPCD Rule 4565 (adopted March 15, 2007), section 5.3.3
and section 3.3 (defining ``alternative mitigation measure'').
    \91\ SJVUAPCD, Final Staff Report, Revised Proposed New Rule
4565 (Biosolids, Animal Manure, and Poultry Litter Operations),
March 30, 2007, at p. 9.
    \92\ SCAQMD, ``Technology Assessment for Proposed Rule 1133
(Emission Reductions from Composting and Related Operations),''
March 22, 2002, at p. 3-4 and 3-5 (``biofilters use microorganism
that live in the biofilm . . . to adsorb and biologically degrade
contaminated air into non-harmful substances. In particular, VOC is
oxidized to carbon dioxide and water, and ammonia is degraded into
nitrate without creating aggravating pollution issues''); see also
SCAQMD Rule 1133.2 (adopted January 10, 2003), section (c)(5)
(defining ``biofiltration'' as ``a pollution control technology that
removes and oxidizes VOC and ammonia through the action of bacteria
and other microorganisms'').
    \93\ SJVUAPCD Rule 4565 (adopted March 15, 2007), sections 5.5
and 5.7.
---------------------------------------------------------------------------

    Similarly, SCAQMD Rule 1133.2, as adopted January 10, 2003,
generally requires operators of ``new'' co-composting facilities (i.e.,
those that started operations after January 10, 2003) with design
capacities of at least 1,000 tons of throughput per year to conduct all
active co-composting within the confines of an enclosure meeting
certain conditions, to conduct all curing using an aeration system
meeting certain conditions, and to vent the exhaust from the enclosure
and aeration system to an emissions control system designed and
operated with a control efficiency of at least 80 percent, by weight,
for both VOC and ammonia emissions.\94\ Alternatively, an operator of a
new co-composting facility may submit a compliance plan, for approval
by the SCAQMD Executive Officer, that demonstrates an overall emission
reduction of 80 percent, by weight, from specified baseline emission
factors for both VOC and ammonia emissions.\95\ Existing co-composting
facilities with design capacities of at least 35,000 tons of throughput
per year must submit a compliance plan that demonstrates an overall
emission reduction of 70 percent, by weight, from specified baseline
emission factors for both VOC and ammonia emissions.\96\ For existing
facilities or new facilities that elect to submit alternative
compliance plans, the compliance plan must specify the operator's
selected control method(s), which may include (among others) enclosure
design or technology; aeration system design and operation;
biofiltration; process controls; or best management practices.\97\
According to the final staff report for SCAQMD Rule 1133.2, a well-
designed, well-operated, and well-maintained biofilter can achieve 80
percent control efficiency for both VOC and ammonia emissions.\98\
---------------------------------------------------------------------------

    \94\ SCAQMD Rule 1133.2 (adopted January 10, 2003), section
(d)(1).
    \95\ Id. at section (d)(2).
    \96\ Id. at sections (d)(3) and (j)(1).
    \97\ Id. at section (e).
    \98\ SCAQMD, Final Staff Report, ``Proposed Rule 1133--
Composting and Related Operations: General Administrative
Requirements; Proposed Rule 1133.1--Chipping and Grinding
Activities; Proposed Rule 1133.2--Emission Reductions from Co-
Composting Operations,'' January 10, 2003, at p. 18 (stating that
``[b]ased on the information collected so far on existing biofilter
composting applications, control efficiencies of about 80% to 90%
for VOC and 70% to over 90% for ammonia have been achieved. . . .
[demonstrating] that a well-designed, well-operated, and well-
maintained biofilter is capable of achieving 80 percent control
efficiency for VOC and ammonia'').
---------------------------------------------------------------------------

    Although SJVUAPCD Rule 4565 does not explicitly require operators
of composting/co-composting facilities to achieve specified levels of
ammonia emission reductions, as does SCAQMD Rule 1133.2, both rules
generally require composting facilities to use enclosures and/or
aeration systems vented to an emission control device with a VOC
control efficiency of 70 or 80 percent. Given the similarity in the
control requirements contained in these rules, we find the requirements
of SJVUAPCD Rule 4565 sufficient to satisfy RACM/RACT requirements for
ammonia control for the 2006 PM2.5 NAAQS.
    We also disagree with Earthjustice's claim that the EPA has
``proposed to excuse the Plan's failure to analyze ammonia controls''
because of the timing of its submission after the D.C. Circuit's
decision in NRDC v. EPA, 706 F.3d 428 (D.C. Cir. 2013). In our proposed
rule, we noted that ``the timing of the NRDC decision in early 2013 may
have constrained the State's and District's ability to fully evaluate
additional ammonia control measures as part of a RACM/RACT control
strategy ahead of the applicable Moderate area attainment date
(December 31, 2015)'' and stated that we were taking this unique
circumstance into account in our evaluation of the Plan.\99\ We also
noted the absence of specific information regarding more stringent
ammonia air emission control measures that may be technologically and
economically feasible for implementation in the SJV area and
recommended that the State and District conduct a more thorough
evaluation of all available ammonia control measures as part of its
development of a Serious area plan for the area.\100\ The commenter
argues generally that the Plan includes no analysis of how the
District's rules control ammonia emissions but provides no specific
information to show that more stringent control measures are
technologically and economically feasible for implementation in the SJV
area.
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    \99\ 80 FR 1816, 1830 (January 13, 2015).
    \100\ Id.
---------------------------------------------------------------------------

    As explained in our proposed rule, sections 172(c)(1) and
189(a)(1)(C) of the Act require that attainment plans for Moderate
nonattainment areas provide for the implementation of RACM and RACT for
existing sources of PM2.5 and PM2.5 precursors in
the nonattainment area as expeditiously as practicable but no later
than 4 years after designation. In longstanding guidance, the EPA has

interpreted the RACM requirement to include any potential control
measure for a point, area, on-road or non-road emission source that is
technologically and economically feasible and is not ``absurd,
unenforceable, or impracticable.'' \101\ The Act does not require
adoption of every conceivable control measure to satisfy the RACM
requirement in a Moderate PM2.5 nonattainment area.\102\
Consistent with the EPA's recommended process for determining RACM/RACT
for a given area, the District compiled a list of potential control
measures for ammonia emission sources in the SJV; evaluated the
identified control measures for ``reasonableness,'' considering
technological and economic feasibility and potentially adverse impacts;
and identified the SIP-approved control measures in the Plan that it
was relying on to implement RACM for ammonia emission sources.\103\
Although the Plan does not contain every conceivable control measure
for ammonia emissions, we find the control evaluations in the Plan
sufficient to demonstrate that it provides for the implementation of
all RACM/RACT for ammonia sources that could reasonably be implemented
by the statutory implementation deadline under CAA section 189(a)(1)(C)
for the 2006 PM2.5 NAAQS. We discuss Earthjustice's specific
comments about SJVUAPCD Rule 4566 in Response 9 below, and its specific
comments about SJVUAPCD Rule 4570 in Response 10 below.
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    \101\ 80 FR 1816, 1826 (January 13, 2015) (citing ``State
Implementation Plans; General Preamble for the Implementation of
Title I of the Clean Air Act Amendments of 1990,'' 57 FR 13498
(April 16, 1992) (General Preamble) at 13540, 13560).
    \102\ See 55 FR 38326 (September 18, 1990) (revoking prior EPA
guidance to the extent it suggested or stated that areas with severe
pollution problems must implement every conceivable control measure
including those that would cause severe socioeconomic disruption to
satisfy RACM).
    \103\ 2014 Supplement at Attachment A (ammonia controls).
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    Comment 9: Earthjustice disputes the District's finding that its
composting rule, Rule 4566, is at least as stringent as SCAQMD Rule
1133.3, and argues that the District failed to consider some of the
requirements of SCAQMD Rule 1133.3 in the table that it used to compare
the two rules. Earthjustice notes that SCAQMD Rule 1133.3 requires
implementation of a mitigation measure that demonstrates emissions
reductions, by weight, of at least 40 percent for VOC and at least 20
percent for ammonia, and that SJVUAPCD Rule 4566 requires a mitigation
measure that demonstrates emissions reductions of VOC of at least 19
percent, and does not regulate ammonia. While noting that ``VOC
emissions reductions may result in some ammonia emissions reductions,''
Earthjustice asserts that because Rule 4566 does not regulate ammonia,
the District cannot rely on the rule to result in a certain amount of
ammonia emissions.
    Response 9: Although SJVUAPCD Rule 4566 does not explicitly
regulate ammonia emissions, we disagree with Earthjustice's suggestion
that the District cannot rely on this rule as part of its RACM/RACT
control strategy for the 2006 PM2.5 NAAQS.
    SJVUAPCD Rule 4566, as adopted August 18, 2011, requires smaller
composting operations to implement at least three turns during active-
phase composting and one of several mitigation measures listed in Table
1 of the rule, such as application of water or a finished compost
cover, or in the alternative to implement an alternative mitigation
measure approved by the APCO and the EPA that demonstrates at least 19
percent reduction, by weight, in VOC emissions.\104\ For larger
composting operations (i.e., those with a total throughput between
200,000 and 750,000 wet tons per year of organic material), Rule 4566
requires operators to apply both watering and a finished compost cover
in addition to implementation of at least three turns during active-
phase composting, or in the alternative to implement an alternative
mitigation measure approved by the APCO and the EPA that demonstrates
at least 60 percent reduction, by weight, in VOC emissions.\105\ For
the largest composting operations (i.e., those with a total throughput
of at least 750,000 wet tons per year of organic material), Rule 4566
requires operators to implement an alternative mitigation measure
approved by the APCO and the EPA that demonstrates at least 80 percent
reduction, by weight, in VOC emissions.\106\
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    \104\ SJVUAPCD Rule 4566 (adopted August 18, 2011), section
5.2.1.
    \105\ Id. at section 5.2.2.
    \106\ Id. at section 5.2.3.
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    SCAQMD Rule 1133.3, as adopted July 8, 2011, establishes similar
requirements for greenwaste composting operations to periodically turn
and water active compost piles and to apply finished compost
covers.\107\ According to the SCAQMD's staff report for Rule 1133.3,
these types of ``good composting practices'' minimize both VOC and
ammonia emissions by balancing the carbon-to-nitrogen ratio and
providing adequate aeration and moisture in the compost.\108\ As
Earthjustice correctly notes, SCAQMD Rule 1133.3 also allows operators
of such operations to implement an alternate mitigation measure
approved by the SCAQMD Executive Officer, CARB, and the EPA that
demonstrates VOC emission reductions by at least 40 percent by weight
and ammonia emission reductions by at least 20 percent by weight.\109\
For composting operations involving greater than 5,000 tons per year of
foodwaste throughput, SCAQMD Rule 1133.3 establishes requirements to
conduct the active phase composting using an emission control device
designed and operated with an overall system control efficiency of at
least 80 percent, by weight, each for VOC and ammonia emissions, or to
implement an alternate mitigation measure approved by the SCAQMD
Executive Officer, CARB, and the EPA that achieves equivalent
reductions in both VOCs and ammonia.\110\
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    \107\ SCAQMD Rule 1133.3 (adopted July 8, 2011), section (d)(2).
    \108\ SCAQMD, Final Staff Report, ``Proposed Amended Rule
1133.1--Chipping and Grinding Activities; Proposed Rule 1133.3--
Emission Reductions from Greenwaste Composting Operations,'' July
2011, at p. 3 (``[g]ood composting practices, which balance the
carbon-to-nitrogen (C:N) ratio and provide adequate aeration and
moisture, will minimize VOC, ammonia and GHG emissions'').
    \109\ SCAQMD Rule 1133.3 (adopted July 8, 2011), section
(d)(2)(E).
    \110\ Id. at section (d)(3).
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    According to CARB, the water management requirements in SJVUAPCD
Rule 4566 and SCAQMD Rule 1133.3 achieve an ammonia control efficiency
of 19 percent, while use of certain kinds of aerated static piles (ASP)
vented to a biofilter achieves an ammonia control efficiency ranging
from 20 to 99 percent.\111\ In the absence of specific information
about more stringent ammonia control requirements for composting
operations that the District could reasonably have implemented by the
statutory implementation deadline for RACM/RACT in this area (December
14, 2013), we find the requirements of SJVUAPCD Rule 4566 adequate to
satisfy RACM/RACT requirements for composting operations for purposes
of the 2006 PM2.5 NAAQS in the SJV.
---------------------------------------------------------------------------

    \111\ CARB, ``ARB Emissions Inventory Methodology for Composting
Facilities'' (posted 2015) at Table III-3 (``Control Techniques for
Composting Operations''), available at http://www.arb.ca.gov/ei/areasrc/Composting%20Emissions%20Inventory%20Methodology%20Final%20Combined.pdf.
---------------------------------------------------------------------------

    Comment 10: Earthjustice comments that the District did not
adequately review Rule 4570 (Confined Animal Facilities) when it
compared it to similar rules in other California districts and the
state of Idaho. According to

Earthjustice, SJVUAPCD Rule 4570 and Idaho's rule ``employ drastically
different methods to reduce emissions from dairies,'' and the District
has not fully explored aspects of the Idaho rule that could strengthen
SJVUAPCD Rule 4570. In particular, Earthjustice asserts that the
District misconstrued a statement by the Idaho Department of
Environmental Quality (Idaho DEQ) that described the Idaho rule as
employing an ``arbitrary'' point system. According to Earthjustice, the
maximum number of points in the system's rating scale was ``arbitrary''
in the sense that another number could have been selected, but the
Idaho DEQ ``thoroughly analyzed the control measures and their
associated ammonia emission reductions,'' and allocated points based on
these reductions. Because the District has not done a similar
evaluation of the measures in SJVUAPCD Rule 4570, Earthjustice asserts,
it has not fully compared the stringency of the rule against the Idaho
rule.
    Earthjustice asserts that the District's comparison of the
stringency of SJVUAPCD Rule 4570 and other California air district
rules is insufficient because the District considered only the number
of mitigation measures required by each district. Earthjustice states
that the District should consider instead the ammonia emissions
reductions achieved under each rule. Further, Earthjustice states, if
the District finds that other air districts' mitigation measures are
more effective in reducing emissions, it should incorporate those
measures into its rule.
    Response 10: We agree that the District appears to have
misconstrued the Idaho DEQ's statement about the point system in Idaho
Rule 58.01.01, sections 760-764 (Rules for the Control of Ammonia from
Dairy Farms) (hereafter ``Idaho CAF Rule'') and that the District
should have considered the ammonia emission reductions achieved under
the rules that it evaluated, rather than simply addressing the number
of mitigation measures required in each rule. For the reasons provided
below, however, we find SJVUAPCD Rule 4570 adequate to satisfy RACM/
RACT requirements for the 2006 PM2.5 NAAQS in the SJV.
    SJVUAPCD Rule 4570, as amended October 21, 2010, requires that CAFs
of certain sizes for dairy cows, other cattle, swine, poultry, and
layer hens implement measures to reduce VOC emissions during feed
operations, manure management and other CAF processes.\112\ Both VOCs
and ammonia are emitted during these activities at CAFs. Given the
large proportion of ammonia emissions that come from cow manure
produced at CAFs,\113\ we focus our evaluation below on measures to
reduce ammonia from the production and handling of cow manure at dairy
CAFs.
---------------------------------------------------------------------------

    \112\ See generally SJVUAPCD Rule 4570 (amended October 21,
2010).
    \113\ ``Ammonia Emissions and Animal Agriculture,'' Susan W. Gay
and Katharine F. Knowlton, Virginia Cooperative Extension, Virginia
Tech, 2009 (noting that ``[a]mmonia is a common by-product of animal
waste due to the often inefficient conversion of feed nitrogen into
animal product. Livestock and poultry are often fed high-protein
feed, which contains surplus nitrogen, to ensure that the animals'
nutritional requirements are met. Nitrogen that is not metabolized
into animal protein (i.e., milk, meat, or eggs) is excreted in the
urine and feces of livestock and poultry where further microbial
action releases ammonia into the air during manure decomposition'').
---------------------------------------------------------------------------

    Ammonia emissions from CAF manure processes may be reduced by
flushing lanes in freestall barns \114\ and limiting manure exposure to
air through land incorporation.\115\ According to the SJVUAPCD,
freestall barns are the largest source of manure at SJV dairies.\116\
Rule 4570 contains mandatory requirements for all dairy CAFs subject to
the rule that house animals in freestalls to frequently clean the
housing flush lanes--specifically, to ``flush or scrape freestall flush
lanes at least three (3) times per day'' or to ``flush, scrape, or
vacuum freestall flush lanes'' immediately before, after, or during
each milking.\117\ In practice, most CAFs in the SJV comply with the
SJVUAPCD Rule 4570 manure management requirements by flushing manure to
dilute the urea in urine, which reduces ammonia emissions,\118\ and by
incorporating solid manure into crop land within 72 hours of land
application.\119\
---------------------------------------------------------------------------

    \114\ W. Kroodsma, J.W.H. Huis In 't Veld & R. Scholtens, 1993,
``Ammonia emissions and its reduction from cubicle houses by
flushing,'' Livestock Production Science 35: 293-302.
    \115\ Ndegwa, P.M., A.N. Hristov, J. Arogo, and R.E. Sheffield,
``A review of ammonia emission mitigation techniques for
concentrated animal feeding operations,'' J. Bioengineering Systems,
ed. 100, 2008, p. 463-464.
    \116\ SJVUAPCD, Final Staff Report: Rule 4570 (October 21,
2010), at p. 9.
    \117\ SJVUAPCD Rule 4570 (amended October 21, 2010) at Section
5.6.1 and Table 4.1.D.2. Milking generally occurs at least twice a
day at a typical dairy CAF. See Walter L. Hurley, Lactation Biology
Web site, ANSC 438, University of Illinois, available at http://ansci.illinois.edu/static/ansc438/Lactation/milkingfrequency.html.
    \118\ Memorandum dated June 15, 2016, from Andy Steckel to Kerry
Drake, EPA Region 9, ``Summary of our 6/10/16 Discussion with Kevin
Abernathy, Milk Producers Council'' and W. Kroodsma, et al., 1993,
``Ammonia emissions and its reduction from cubicle houses by
flushing,'' Livestock Production Science 35: 293-302, at p. 300
(noting that ``[f]lushing has a significant emission reducing effect
[because] . . . the urea concentration on slats, concrete floors and
in the top layer of the slurry is lowered by dilution''); see also
SJVUAPCD, Final Staff Report: Rule 4570 (October 21, 2010), at p. 10
(noting that ``[l]iquid systems are common in large dairies due to
their lower labor costs and ease of use with automatic flushing
systems'').
    \119\ Memorandum dated June 15, 2016, from Andy Steckel to Kerry
Drake, EPA Region 9, ``Summary of our 6/10/16 Discussion with Kevin
Abernathy, Milk Producers Council''; see also email dated June 9,
2016, from Samir Sheikh of the SJVUAPCD to Kerry Drake of EPA Region
9, regarding ``Manure Land Application.''
---------------------------------------------------------------------------

    In addition, SJVUAPCD Rule 4570 requires each owner/operator of a
large dairy CAF that handles or stores solid manure or separated solids
outside the animal housing to remove dry manure or separated solids
from the facility or cover it with a weatherproof covering from October
through May, within 72 hours of collecting it, or to implement an
``alternative mitigation measure'' \120\ approved by CARB and the
EPA.\121\ SJVUAPCD Rule 4570 provides, in Table 4.1.H, specific
requirements for applying manure to agricultural lands on the facility
including the option to incorporate all solid manure within 72 hours.
---------------------------------------------------------------------------

    \120\ ``Alternative Mitigation Measure'' is defined in Rule 4570
as ``a mitigation measure that is determined by the APCO, CARB, and
EPA to achieve reductions that are equal to or exceed the reductions
that would be achieved by other mitigation measures listed in this
rule that owners/operators could choose to comply with rule
requirements.'' SJVUAPCD Rule 4570 (amended October 21, 2010),
Section 3.4.
    \121\ SJVUAPCD Rule 4570 (amended October 21, 2010), Section
5.6.1 at Table 4.1.F.
---------------------------------------------------------------------------

    We are aware of only two rules implemented in other areas that
explicitly regulate ammonia emissions from dairy facilities--the Idaho
CAF Rule and SCAQMD Rule 1127 (Emission Reductions from Livestock
Waste).\122\ The Idaho CAF Rule assigns points to each ammonia
mitigation measure listed in the rule and requires dairy farm operators
to implement measures that collectively achieve at least 27
points.\123\ The rule only applies,

however, to dairy farms containing between 1,638 and 5,063 cows,
depending on the type of dairy facility.\124\ SJVUAPCD Rule 4570, on
the other hand, applies to dairy CAFs containing at least 500 milking
cows and also applies to other types of CAFs, including beef cattle
feedlots, other cattle facilities, poultry facilities, and swine
facilities.\125\ As we stated in our proposed rule, because the
structure of the Idaho CAF Rule differs substantially from the
structure of SJVUAPCD Rule 4570, it is difficult to compare the
requirements in these two rules directly.\126\
---------------------------------------------------------------------------

    \122\ See Idaho Administrative Code 58.01.01, section 760, and
SCAQMD Rule 1127 (adopted August 6, 2004), paragraph (a). Other CAF
rules in California include SCAQMD Rule 223, BAAQMD Rule 2-10,
SMAQMD Rule 496, VCAPCD Rule 23, Imperial County APCD (ICAPCD) Rule
217, and Butte County AQMD Rule 450. Each of these rules also
regulates CAFs but does not establish specific requirements for
ammonia control. For example, SCAQMD Rule 223 (adopted June 2, 2006)
identifies ammonia as a precursor to particulates, but its
requirements are very similar to SJVUAPCD Rule 4570 as originally
adopted June 15, 2006. Similarly, ICAPCD Rule 217 states that its
purpose is to limit emissions of VOC and ammonia, but the mitigation
requirements are generally equivalent to those in SJVUAPCD Rule
4570.
    \123\ Idaho Administrative Code 58.01.01, section 764, paragraph
01 (``Dairy farm best management practices'') (requiring dairies to
``employ BMPs for the control of ammonia to total twenty-seven (27)
points'').
    \124\ Id. at section 761 (``General applicability'').
    \125\ SJVUAPCD Rule 4570 (amended October 21, 2010), Table 2 and
Section 5.6.
    \126\ 80 FR 1816, 1829-30 (January 13, 2015) (noting, for
example, that the Idaho CAF Rule identifies certain mitigation
measures that are not included in SJVUAPCD Rule 4570, while Rule
4570 contains more stringent applicability thresholds and provisions
for testing and records retention).
---------------------------------------------------------------------------

    Additionally, according to information submitted by the SJVUAPCD,
the option in the Idaho CAF Rule to cover synthetic lagoons (one of the
key mitigation measures in the rule) would not be effective in the SJV
and could increase ammonia emissions at CAFs in the SJV.\127\
Furthermore, the Idaho CAF Rule states that ``[p]oints may be obtained
through third party export with sufficient documentation'' and that
``[a]s new information becomes available or upon request, the Director
may determine a practice not listed in the table constitutes a BMP and
assign a point value.'' \128\ These ambiguously phrased provisions
allow CAF owners/operators to comply with the rule by implementing
measures entirely different from those listed in the rule that may or
may not be effective in reducing ammonia emissions. The commenter has
provided no information to support a conclusion that the requirements
of the Idaho CAF Rule will actually achieve ammonia emission
reductions, nor any information to indicate that the requirements of
this rule are more stringent than those in SJVUAPCD Rule 4570.
---------------------------------------------------------------------------

    \127\ Email dated June 25, 2015 from Sheraz Gill of the SJVUAPCD
to Andrew Steckel of EPA Region 9, regarding ``Requested
Information'' and attachment, ``Evaluation of Covers Lagoons Manure
Piles for NH3.pdf.''
    \128\ Idaho Administrative Code 58.01.01, at section 764-01
(``BMPs'').
---------------------------------------------------------------------------

    SCAQMD Rule 1127, as adopted August 6, 2004, applies only to
livestock waste (i.e., manure management) at dairy farms and related
operations. Unlike SJVUAPCD Rule 4570, which explicitly requires that
dairy CAFs regularly flush, scrape, or vacuum freestall flush
lanes,\129\ SCAQMD Rule 1127 contains no analogous requirement to
regularly clean flush lanes in freestall barns.\130\ SCAQMD Rule 223,
as adopted June 2, 2006, contains menu-based options for flushing,
scraping, or vacuuming freestall barns but does not specifically
mandate such measures.\131\
---------------------------------------------------------------------------

    \129\ SJVUAPCD Rule 4570 (amended October 21, 2010) at Section
5.6.1 and Table 4.1.D.2. Milking generally occurs at least twice a
day at a typical dairy CAF. Walter L. Hurley, Lactation Biology Web
site, ANSC 438, University of Illinois at http://ansci.illinois.edu/static/ansc438/Lactation/milkingfrequency.html.
    \130\ SCAQMD Rule 1127 does require dairies to remove manure
accumulated in corrals at least 4 times per year and to remove
manure stockpiles within 3 months of the last corral clearing day,
and no more than 3 months after the date that previous stockpiles
were last completely cleared. SCAQMD Rule 1127 (adopted August 6,
2004), sections (d)(4) and (d)(5).
    \131\ SCAQMD Rule 223, Appendix A, Table 1.C (requiring owners/
operations at large dairy CAFs that house animals in freestall barns
to implement at least 2 of 9 listed mitigation measures, including
measures to regularly flush, scrape or vacuum freestalls).
---------------------------------------------------------------------------

    Additionally, SCAQMD Rule 1127 requires that a dairy operator
disposing of manure within the South Coast area remove or contract to
remove the manure to a manure processing operation approved in
accordance with specific requirements and/or to agricultural land
within the SCAQMD approved by local ordinance and/or the regional water
quality board for the spreading of manure.\132\ Rule 1127 does not
require that manure be incorporated into agricultural land within any
specific timeframe to reduce ammonia emissions.
---------------------------------------------------------------------------

    \132\ Id. at section (e).
---------------------------------------------------------------------------

    Thus, neither SJVUAPCD Rule 4570 nor SCAQMD Rule 1127 strictly
requires dairy CAF operators to promptly remove and dispose of
collected manure to minimize ammonia emissions. The commenter has
failed to identify any measure implemented in the South Coast or
elsewhere that is more stringent than the requirements of SJVUAPCD Rule