Document ID: EPA-R09-OAR-2006-0583-0033
Agency: epa
Document Type: Rule
Title: Approval and Promulgation of Implementation Plans; Designation of Areas for Air Quality Planning Purposes; State of California; PM-10; Determination of Attainment for the San Joaquin Valley Nonattainment Area; Determination Regarding Applicability of Certain Clean Air Act Requirements
Posted Date: 2006-10-30T05:00Z

[Federal Register: October 30, 2006 (Volume 71, Number 209)]
[Rules and Regulations]               
[Page 63641-63664]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30oc06-24]                         

[[Page 63641]]

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Part III

Environmental Protection Agency

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40 CFR Parts 52 and 81

 Approval and Promulgation of Implementation Plans; Designation of 
Areas for Air Quality Planning Purposes; State of California; PM-10; 
Determination of Attainment for the San Joaquin Valley Nonattainment 
Area; Determination Regarding Applicability of Certain Clean Air Act 
Requirements; Final Rule

[[Page 63642]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R09-OAR-2006-0583, FRL-8234-1]

 
Approval and Promulgation of Implementation Plans; Designation of 
Areas for Air Quality Planning Purposes; State of California; PM-10; 
Determination of Attainment for the San Joaquin Valley Nonattainment 
Area; Determination Regarding Applicability of Certain Clean Air Act 
Requirements

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is finalizing its determination that the San Joaquin 
Valley nonattainment area (SJV or the Valley) in California has 
attained the National Ambient Air Quality Standards (NAAQS) for 
particulate matter with an aerodynamic diameter less than or equal to a 
nominal 10 micrometers (PM-10). This determination is based upon 
monitored air quality data for the PM-10 NAAQS during the years 2003-
2005. The SJV continues to attain the PM-10 NAAQS in 2006 based on the 
latest available quality assured data. EPA is also finalizing its 
determination that, because the SJV has attained the PM-10 NAAQS, 
certain Clean Air Act (CAA or the Act) requirements are not applicable 
for as long as the SJV continues to attain the PM-10 NAAQS.

DATES: Effective Date: This rule is effective October 30, 2006.

ADDRESSES: You can inspect copies of the docket for this action at 
EPA's Region IX office during normal business hours by appointment at 
the following locations:
    Environmental Protection Agency, Region IX, 75 Hawthorne Street, 
San Francisco, CA 94105-3901.
    Air and Radiation Docket and Information Center, U.S. Environmental 
Protection Agency, Room B-102, 1301 Constitution Avenue, NW. (Mail Code 
6102T), Washington, DC 20460.

FOR FURTHER INFORMATION CONTACT: Doris Lo, EPA Region IX, (415) 972-
3959, lo.doris@epa.gov.

SUPPLEMENTARY INFORMATION: Throughout this document, ``we,'' ``us'' and 
``our'' refer to EPA.

Table of Contents

I. Summary of Proposed and Final Actions
II. Public Comments and EPA Responses
    A. Environmental Justice
    B. The Clean Data Policy
    C. New Particulate Matter (PM) NAAQS
    D. EPA Policy on Special Purpose Monitoring Data
    E. Adequacy of the SJV Monitoring Network
    F. Data Not Included in Determining Attainment
    1. Data From September 3, 2004 High Wind Event
    2. Data From BAM and TEOM Monitors
    G. Representativeness of Data
    H. Other Comments
III. Final Action
IV. Effective Date of This Final Action
V. Statutory and Executive Order Reviews

I. Summary of Proposed and Final Actions

    On July 19, 2006, EPA proposed to determine that the SJV has 
attained the 24-hour and annual NAAQS for PM-10 (71 FR 40952).\1\ The 
proposed determination was based upon monitored air quality data during 
the years 2003-2005 which indicated that there were no violations 
during that time. This data is summarized in table 1 in the proposed 
rule. 71 FR at 40953-54. EPA also based its proposed determination on 
monitored air quality data indicating the area continued to attain in 
2006. EPA also proposed to determine that certain Clean Air Act (CAA or 
the Act) requirements were not applicable for as long as the SJV 
continued to attain the PM-10 NAAQS. Specifically, for the SJV, EPA 
proposed to determine that the CAA section 172(c)(9) contingency 
measure requirement for the area is suspended. For a more detailed 
discussion of the related background for the SJV and of the proposal, 
please refer to the proposed rule.
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    \1\ On September 21, 2006, EPA signed a final rule revoking the 
annualPM-10 standard. That revocation will be effective 60 days from 
publication of the rule in the Federal Register. Since the 
revocation will not be effective until after our attainment 
determination for the SJV, we are taking final action determining 
that the area has attained both the annual and 24-hour PM-10 
standard.
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    In this notice EPA is finalizing its determination that the SJV has 
attained the NAAQS, based upon three years of complete, quality-assured 
monitored air quality data for 2003-2005, and based upon its 
determination that the area continues to attain the PM-10 NAAQS in 2006 
based on quality assured data submitted to EPA's AQS Database through 
July 31, 2006. See AQS Report AMP350 titled ``SJV PM-10 SLAMS Raw Data 
Report January 2003-July 2006'' included in the docket for this notice. 
In finalizing its determination, EPA has also reviewed preliminary 
monitoring data for monitors in the SJV that has become available since 
July 31, 2006.
    EPA learned recently of preliminary data indicating that 
exceedances of the standard were monitored on September 22, 2006 at 
State and Local Air Monitoring Station (SLAMS) monitors in Corcoran 
(215 [mu]g/m3), Bakersfield-Golden State Hwy. (157 [mu]g/
m3), and Oildale (162 [mu]g/m3).\2\ The 
California Air Resources Board (CARB) and the San Joaquin Valley Air 
Pollution Control District (District) have informed EPA that, based on 
preliminary analysis, they believe that these exceedances are due to 
high wind and wildfire natural events. CARB notified EPA that it 
intends to flag these data as caused by natural events and to request 
that EPA concur with these flags. As such the data would not be 
included for consideration in a determination of attainment for the 
SJV, pursuant to EPA's Natural Events Policy.\3\ Because these data, 
which were collected using manual reference method samplers, are 
preliminary and have not been quality-assured, and because EPA believes 
that they may qualify as caused by natural events, and thus be excluded 
from consideration in an attainment determination, EPA is proceeding to 
finalize its determination that the area is in attainment. If, after 
the data is quality-assured, and after further evaluating CARB's 
request with respect to these data, EPA determines that the data do not 
qualify for exclusion under EPA's natural events policy, and EPA 
further believes that if included that they would establish that the 
area is in violation of the NAAQS, EPA will proceed with appropriate 
rulemaking action to withdraw its determination of attainment.
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    \2\ 24-hour PM-10 exceedances were also recorded on September 
22, 2006 with the automated equivalent (Beta Attenuation Mass/
Tapered Element Oscillating Microbalance) PM-10 analyzers operated 
at the Bakersfield-Golden and Corcoran sites, as well as the Beta 
Attenuation Mass monitor at the Tracy site. See response to comment 
15 below.
    \3\ EPA's NEP Memorandum from Mary D. Nichols, Assistant 
Administrator for Air and Radiation to Regional Air Directors, 
``Areas Affected by PM-10 Natural Events'', May 30, 1996.
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    EPA is also finalizing its determination that, because the SJV has 
attained the PM-10 NAAQS, certain requirements, and specifically the 
contingency measure requirement of section 172(c)(9) of the Clean Air 
Act, do not apply to the SJV area for so long as the area continues to 
attain the NAAQS.

II. Public Comments and EPA Responses

    EPA received one comment letter in support of our proposal from the 
District stating that the determination is a result of ``nearly two 
decades of intense efforts to reduce emissions of PM-10 and its 
precursors.'' The District also states that

[[Page 63643]]

``emissions of PM-10 and its precursors have decreased by about 24% 
since 1990'' which is significant given the population growth. Finally 
the District states that this determination ``does not in any way imply 
or allow the District or CARB to relax air quality strategies'' and 
will allow the District to better dedicate resources for upcoming plans 
that will focus on PM-2.5 and ozone attainment.
    EPA received one adverse comment letter from Earthjustice, 
representing Medical Advocates for Healthy Air, Sierra Club, Latino 
Issues Forum, Steven and Michele Kirsch Foundation, the Center for 
Biological Diversity, El Comite para el Bienestar de Earlimart/The 
Committee for the Well Being of Earlimart, Fresno Metro Ministry and 
the Coalition for Clean Air. EPA also received approximately 2000 
adverse comment letters from individual citizens. Many of these 
comments were form letters that contained identical comments. EPA 
addresses all of the specific comments raised by Earthjustice in its 
responses to comments numbers 1 to 24. EPA is responding to many of the 
individual citizens' comments in responses to comments numbers 25 and 
26 and in the context of the responses to Earthjustice, since they 
raised many of the same issues.

A. Environmental Justice

    Comment 1: EPA received comments arguing that its process for 
making this determination did not adequately consider EPA's 
environmental justice mission: ``[t]o achieve equal environmental 
protection so no segment of the population, regardless of race, 
ethnicity, culture or income bears an undue burden of environmental 
pollution and to ensure that the benefits of environmental protection 
are shared by everyone.'' The principal environmental justice 
commenter, Earthjustice, argues that most sources of PM-10 pollution in 
the Valley are located in agricultural areas where population densities 
are low, but percentages of minority and low-income residents are high. 
The comment claims that EPA has not adequately investigated whether 
such areas, particularly in the western part of the Valley, are in 
attainment and is not adequately monitoring those areas. Without more 
thorough investigation and monitoring of air quality in the western 
part of the Valley, the comment concludes, EPA cannot ``carry out its 
environmental justice mandate.''
    Response: EPA is committed to environmental justice, and a November 
2005 memorandum by Administrator Johnson has reiterated EPA's ``ongoing 
commitment to ensure environmental justice for all people, regardless 
of race, color, national origin, or income.'' EPA believes that this 
attainment determination is fully consistent with that commitment, and 
ensures environmental protection for all residents of the Valley, 
including residents of the western part of the Valley, and regardless 
of race, color, national origin, or income.
    The gist of the environmental justice argument is that EPA has not 
adequately investigated and analyzed air quality in minority and low-
income communities in the western part of the Valley. Although that is 
framed as an environmental justice argument, it is really a challenge 
to the adequacy of the legal basis for EPA's determination that the 
entire Valley is in attainment. As explained more fully elsewhere, EPA 
has an adequate factual and legal basis for that determination, and has 
assessed air quality through monitored data that is representative of 
all areas of the Valley, including the west side, minority and low 
income communities addressed in the comment. Thus, the commenter is 
mistaken in claiming that EPA failed to investigate those areas 
adequately, or that such a purported failure prevented the Agency from 
adequately implementing environmental justice.
    Similarly, EPA rejects claims that the monitoring conducted by the 
State and District is deficient. As explained more fully elsewhere, the 
District's monitoring network provides for adequate and accurate 
assessments of air quality throughout the Valley, including minority 
and low income communities in the western area.
    Comment 2: Commenters, principally Earthjustice, assert that low 
income and minority populations were not provided an adequate 
opportunity to comment on the rule. Earthjustice asserts that ``the 
concerned people of the Valley'' sought an ``opportunity to be heard,'' 
and unsuccessfully requested that EPA hold a hearing. That comment also 
points out that many west side residents ``do not speak English, do not 
own computers, and do not have the time or expertise to draft public 
comments.''
    Response: EPA believes that interested parties were given adequate 
opportunities to comment on the proposed determination of attainment. 
Section 553(c) of the Administrative Procedure Act (APA), which governs 
informal rulemaking actions, such as determinations of attainment, does 
not require EPA to provide for a hearing. Section 553 (c) states that:

    The agency shall give interested persons an opportunity to 
participate in the rulemaking through submission of written data, 
views, or arguments with or without opportunity for oral 
presentation.

    EPA does not, as a matter of standard practice, conduct hearings on 
determinations of attainment. EPA does not believe a hearing was needed 
in this case, or would have been an appropriate use of the Agency's 
limited resources. EPA also does not agree with the commenters' 
implicit suggestion that, without a hearing, Valley residents had no 
forum for expressing their concerns.
    EPA believes that the opportunity to provide written comments was 
sufficient for providing input from the public. That gave interested 
parties an opportunity to present data, views and arguments through 
written comments. No showing has been made that the opportunity to 
provide written comments precluded meaningful public participation. To 
the contrary, EPA received comments that identified and expansively 
discussed the concerns of minority and low income communities in the 
Valley. Thus, EPA does not agree with the suggestion that Valley 
residents, or anyone else, did not have adequate input into Agency 
decision making.

B. The Clean Data Policy

    Comment 3: The commenter contends that EPA cannot use its Clean 
Data Policy to exempt the District from subpart 4 requirements. The 
commenter notes that EPA cites to two EPA memoranda incorporated into 
EPA's Phase 2 8-hour ozone implementation rule, and relies on other 
attainment findings and redesignations that interpret the Clean Data 
Policy to justify waiving CAA requirements for PM-10 areas. The 
commenter argues that EPA provides none of its own analysis for 
proposing that the attainment determination will relieve the District 
of the obligation to comply with CAA requirements for reasonably 
available control measures (``RACM''), attainment demonstrations, 
reasonable further progress (``RFP'') and contingency measures. The 
commenter also alleges that EPA improperly expands the Clean Data 
Policy by claiming that the District will no longer be subject to the 
RACM requirements of the Act. The commenter further contends that even 
if one were to accept EPA's argument, it would not apply to the SJV 
because as a serious PM-10 nonattainment area the Valley is subject to 
the BACM requirements of section 189(b)(1)(B). The commenter notes that 
EPA's Addendum to the General Preamble makes clear that unlike RACM, 
determinations of BACM

[[Page 63644]]

are not tied to what is necessary for attainment. The commenter points 
out that the proposal correctly omits BACM from the list of CAA 
requirements waived under the Clean Data Policy, but requests that the 
final rule should be explicit that the BACM requirement is maintained.
    Response: As noted in the proposal, EPA has previously approved all 
of the serious area PM-10 attainment plan requirements for the SJV 
except for the contingency measure requirements of CAA section 
172(c)(9). See 69 FR 30006 (May 26, 2004) approving the 2003 PM-10 Plan 
for the SJV. In that action, EPA approved the RFP, attainment and RACM/
BACM demonstrations for the SJV. Thus the issue of whether these 
requirements should be suspended is not before us, except insofar as 
our reasoning for why the contingency measures requirement is suspended 
rests on the rationale for suspending the attainment demonstration and 
RFP requirements. Nevertheless, as explained below, EPA believes that 
once the area attains the standards the RFP, attainment and RACM 
demonstrations would not be needed even though they have already been 
approved.
    That said, EPA is correct in applying the Clean Data Policy in its 
determination of attainment in the SJV, and affirms the Agency's 
interpretation of subparts 1 and 4 of part D of the CAA. As EPA noted 
in its proposal, the Clean Data Policy has been applied in the context 
of the 1-hour and 8-hour ozone standards as well as in a number of PM-
10 rulemakings. EPA's discussion of the application of the Clean Data 
Policy is set forth at length in its proposed rulemaking on Weirton, 
West Virginia 71 FR 27440, 27443-27445 (May 11, 2006), as well as in 
the memoranda and rulemakings cited therein. As we explained in that 
notice, the reasons for relieving an area that has attained the 
relevant standard of certain part D, subpart 1 and 2 obligations, apply 
equally as well to part D, subpart 4, which contains specific 
attainment demonstration and RFP provisions for PM-10 nonattainment 
areas.
    EPA's analysis of the Clean Data Policy as it applies to PM-10 
areas was contained in the documents cited in the proposal. Contrary to 
commenter's contention, the fact that EPA's analysis was provided in 
prior memoranda and rulemakings does not detract from the fact that it 
is EPA's own analysis. Indeed, EPA's consistency in the application of 
its interpretation lends it added weight. We reiterate here that EPA's 
analysis of its legal interpretation can be found in its ``Final Rule 
to Implement the 8-hour Ozone National Ambient Air Quality Standard--
Phase 2'' (Phase 2 Final Rule) 70 FR 71612, 71645-71646 (November 29, 
2005) and the rulemakings and memoranda cited therein, the May 10, 1995 
memorandum from John S. Seitz, entitled ``Reasonable Further Progress, 
Attainment Demonstration, and Related Requirements for Ozone 
Nonattainment Areas Meeting the Ozone National Ambient Air Quality 
Standard,'' the December 14, 2004 memorandum from Stephen D. Page, 
entitled, ``Clean Data Policy for the Fine Particle National Ambient 
Air Quality Standards,'' and rulemakings concerning the application of 
the policy to PM--10 areas--71 FR 6352, 6354 (February 8, 2006); 71 FR 
13021, 13024 (March 14, 2006); and 71 FR 27440, 27443-27444 (May 11, 
2006).
    Furthermore, three U.S. Circuit Courts of Appeals have upheld EPA 
rulemakings applying EPA's interpretation of subparts 1 and 2 with 
respect to clean data for ozone. Sierra Club v. EPA, 99 F.3d 1551 (10th 
Cir. 1996); Sierra Club v. EPA, 375 F.3d 537 (7th Cir. 2004); Our 
Children's Earth Foundation v. EPA, No. 04-73032 (9th Cir. June 28, 
2005) (Memorandum Opinion). EPA has also set forth its legal rationale 
for the Clean Data Policy in briefs filed in these cases, and hereby 
incorporates those briefs insofar as relevant here. See Sierra Club v. 
EPA, No. 95-9541 (10th Cir.), Sierra Club v. EPA, No. 03-2839, 03-3329 
(7th Cir.), Our Children's Earth Foundation v. EPA, No. 04-73032 (9th 
Cir.).\4\
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    \4\ These briefs are in the docket for this rulemaking.
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    As EPA noted in those memoranda and rulemakings, EPA believes it is 
reasonable to interpret the provisions regarding attainment 
demonstrations, reasonable further progress, RACM requirements, 
contingency measures, and other related requirements as being suspended 
and as not requiring further submissions to achieve attainment for so 
long as the area is in fact attaining the standards. Under the policy, 
EPA is not granting an exemption from any applicable requirements under 
part D. Rather, EPA has interpreted these provisions as not requiring 
submissions for so long as the area remains in attainment with the 
standard. This is not a waiver of requirements that by their terms 
apply; it is a determination that certain requirements are written so 
as to be operative only if the area is not attaining the standards. 
Thus, in making its determination of attainment, EPA is also concluding 
that certain subpart 4 and subpart 1 requirements are no longer 
applicable for so long as the area remains in attainment.
    With respect to the requirement for attainment demonstrations, EPA 
believes that the statutory requirement for an attainment 
demonstration--a SIP revision which identifies the level of future 
reductions needed to achieve the NAAQS and any additional adopted 
measures needed to achieve these reductions `` is written so as to be 
inapplicable once the NAAQS is attained. Section 189(a)(1)(B) requires 
that the plan provide for ``a demonstration (including air quality 
modeling) that the [SIP] will provide for attainment by the applicable 
attainment date. * * *'' Section 189(b)(1) further requires that 
serious PM-10 nonattainment areas submit:

    (A) A demonstration (including air quality modeling)--
    (I) that the plan provides for attainment of the national 
ambient air quality standard by the applicable attainment date, or 
(ii ) for any area for which the State is seeking, pursuant to 
section 188(e), an extension of the attainment date beyond the date 
set forth in section 188(c), that attainment by that date would be 
impracticable, and that the plan provides for attainment by the most 
expeditious alternative date practicable.

    If an area is already monitoring attainment, EPA believes that 
Congress intended no requirement for an area to make a further 
submission containing additional measures to achieve attainment. Since 
the SJV area is already in attainment, there is no need for it to 
submit a plan demonstrating how the area will reach attainment had it 
not already done so. This is consistent with the interpretation of the 
section 172(c)(1) attainment demonstration requirement that EPA 
provided in the General Preamble and the Page memorandum, and of the 
section 182(b) and (c) requirements set forth in the Seitz memorandum. 
As EPA stated in the General Preamble, no other measures to provide for 
attainment would be needed by areas seeking redesignation to attainment 
since ``attainment will have been reached.'' 57 FR at 13564.
    We note that the commenter offered no specific critique of EPA's 
interpretation of the Clean Data Policy with regard to the attainment 
demonstration requirement. In addition, EPA's conclusion is consistent 
with the rule of statutory construction that statutes should be 
construed to avoid absurd results and favor public convenience. Because 
the SJV has already reached attainment based on existing measures, no 
additional measures to demonstrate attainment are required. Thus, under 
the language of section 172(c)(1), section 189(a)(1)(B) and section 
189(b)(1), an attainment

[[Page 63645]]

demonstration would be the empty set. EPA therefore believes that, in 
the context of evaluating whether the contingency measure requirement 
is suspended, because the SJV area is attaining the standard, the 
attainment demonstration requirement would also be suspended for so 
long as the area remains in attainment, had it not already been 
approved.
    As for the suspension of the RACM requirement, it does not have 
significance in the context of the SJV, because, as the commenter 
notes, BACM, which goes beyond RACM, has already been approved for the 
SJV, and BACM would not be suspended by the determination of attainment 
because as petitioner notes the BACM requirement is not tied to 
attainment needs. Thus EPA need not further address whether the 
requirement for RACM is suspended in accordance with the Clean Data 
Policy.
    Comment 4: The commenter alleges that EPA relies heavily on the 
proposed redesignation of Weirton, West Virginia, to provide the 
analysis for waiving the RFP requirements for PM-10 areas. The 
requirements for PM-10 areas are found in CAA section 189(c)(1). The 
commenter argues that EPA's analysis ignores the plain language of the 
CAA. The commenter claims that the decisions in Our Children's Earth 
Foundation v. EPA, No. 04-73032 (9th Cir. June 28, 2005) (Memorandum 
Opinion) and Sierra Club v. EPA, 99 F.3d 1551, 1555 (10th Cir. 1996) 
upheld EPA's interpretation based on the Court's finding of ambiguity 
in the statutory language in sections 172(c)(1), (2), and (9) and 
section 182(b)(1)(A)(I). The commenter asserts that, unlike those 
provisions, the language of section 189(c)(1) is perfectly clear. The 
commenter contends that milestones are to be set to show reasonable 
further progress and an area is required to submit revisions 
demonstrating that it has achieved those milestones every three years 
until the area is ``redesignated.'' The commenter concludes that there 
is no ambiguity and that appeals to policy objections cannot rewrite 
clear language into something ambiguous.
    The commenter adds that references in the Weirton notice to other 
provisions in section 189 are unavailing. Section 189(c)(3) requires 
areas that fail to achieve a milestone to submit revisions to assure 
the next milestone will be met. The commenter asserts that this 
obligation continues through the final milestone. Where there is ``no 
next milestone'' the final revision must ensure that the area will 
attain the NAAQS. The commenter states that nothing in these 
requirements is internally inconsistent or prevents areas from 
complying with the plain language of section 189(c)(2).
    The commenter contends that arguments that this amounts to 
``overcontrol'' are without merit. The commenter argues that a key 
distinction between a finding of attainment and redesignation is that a 
redesignation requires EPA to find that ``the improvement in air 
quality is due to permanent and enforceable reductions in emissions.'' 
CAA section 107(d)(3)(E)(iii). The commenter argues that since EPA is 
not making such a finding, it is rational for Congress to have insisted 
that an area continue to reduce emissions until that showing can be 
made and the area can be redesignated.
    Response: EPA's interpretation does not ``waive'' requirements nor 
does it ignore the plain language of the statute. With respect to RFP, 
it has been EPA's longstanding interpretation that the general 
provisions of part D, subpart 1 of the Act (sections 171 and 172) do 
not require the submission of SIP revisions concerning RFP for areas 
already attaining the ozone NAAQS. In the General Preamble, we stated:

    [R]equirements for RFP will not apply in evaluating a request 
for redesignation to attainment, since, at a minimum, the air 
quality data for the area must show that the area has already 
attained. A showing that the State will make RFP toward attainment 
will, therefore, have no meaning at that point.

57 FR at 13564. EPA believes that the same reasoning applies to the PM-
10 provisions of part D, subpart 4.
    Section 171(1) (section 7501 (1)) states that for purposes of part 
D of title I, RFP ``means such annual incremental reductions in 
emissions of the relevant air pollutant as are required by this part or 
may reasonably be required by the Administrator for the purpose of 
assuring attainment of the applicable national ambient air quality 
standard by the applicable date.'' Thus, whether dealing with the 
general RFP requirement of section 172(c)(2), the ozone-specific RFP 
requirements of sections 182(b) and (c), or the specific RFP 
requirements for PM-10 areas of part D, subpart 4, section 189(c)(1), 
the stated purpose of RFP is to ensure progress towards attainment by 
the applicable attainment date. Section 189(c)(1) states that:

    Plan revisions demonstrating attainment submitted to the 
Administrator for approval under this subpart shall contain 
quantitative milestones which are to be achieved every 3 years until 
the area is redesignated to attainment and which demonstrates 
reasonable further progress, as defined in section 7501a(1) of this 
title, toward attainment by the applicable date.

Although this section states that revisions shall contain milestones to 
be achieved ``until the area is redesignated to attainment,'' it 
further specifies that these are milestones that ``demonstrate 
reasonable further progress, as defined in section 7501(1) of this 
title, toward attainment by the attainment date.'' They are also to be 
included in ``plan revisions demonstrating attainment.'' Thus such 
milestones have the purpose of showing reasonable further progress 
``toward attainment by the applicable date,'' as defined in section 
171. It is therefore clear from the language of the statute that once 
the area has attained the standard, no further milestones are necessary 
or meaningful. By definition, the ``reasonable further progress'' 
provision requires only such reductions in emissions as are necessary 
to attain the NAAQS by the attainment date. This interpretation is 
supported by language in section 189(c)(3), which mandates that a state 
that fails to achieve a milestone must submit a plan that assures that 
the state achieve the next milestone or attain the NAAQS if there is no 
next milestone. Section 189(c)(3) assumes that the requirement to 
submit and achieve milestones does not continue after attainment of the 
NAAQS. Thus, once attainment has been reached, there are no further 
milestones to be achieved, even though the area has not yet been 
redesignated to attainment, for so long as the area remains in 
attainment. The commenter is therefore incorrect in asserting that 
section 189(c)(1) is ``perfectly clear'' in requiring additional RFP 
milestones after attainment has been reached.
    In the General Preamble, we noted with respect to section 189(c) 
that ``the purpose of the milestone requirement is to `provide for 
emission reductions adequate to achieve the standards by the applicable 
attainment date' (H.R. Rep. No. 490 101st Cong., 2d Sess. 267 
(1990)).'' 57 FR 13539 (April 16, 1992). If an area has in fact 
attained the standards, the stated purpose of the RFP requirement will 
already have been fulfilled--the only milestones that are required are 
those that demonstrate reasonable further progress toward attainment, 
as defined by section 171. Thus we believe that it is a distinction 
without a difference that section 189(c)(1) speaks of the RFP 
requirement as one to be achieved until an area is ``redesignated to 
attainment,'' as contrasted to section 172(c)(2), which is silent on 
the period to which the requirement pertains, or the ozone 
nonattainment area RFP requirements in

[[Page 63646]]

sections 182(b)(1) or 182(c)(2), which refer to the RFP requirements as 
applying until the ``attainment date,'' since section 189(c)(1) makes 
clear that the milestones that are to be achieved are those that 
demonstrate RFP toward attainment by the applicable attainment date, 
and since section 189(c)(1) defines RFP by reference to section 171(1) 
of the Act. Reference to section 171(1) makes clear that, as with the 
general RFP requirements in section 172(c)(2) and the ozone-specific 
requirements of section 182(b)(1) and 182(c)(2), the PM-specific RFP 
requirements may only be required ``for the purpose of ensuring 
attainment of the applicable national ambient air quality standard by 
the applicable date.'' 42 U.S.C. 7501(1). EPA interprets the RFP 
requirements, in light of the language of section 189(c)(1) and the 
definition of RFP in section 171(1) incorporated therein, to be a 
requirement that no longer applies so long as the standard has been 
attained.
    Similarly, the requirements of section 189(c)(2) with respect to 
milestones no longer apply so long as an area has attained the 
standard. Section 189(c)(2) provides in relevant part that:

    Not later than 90 days after the date on which a milestone 
applicable to the area occurs, each State in which all or part of 
such area is located shall submit to the Administrator a 
demonstration * * * that the milestone has been met.

Where the area has attained the standard and there are no further 
milestones, there is no further requirement to make a submission 
showing that such milestones have been met. As noted above, this is 
consistent with the position that EPA took with respect to the general 
RFP requirement of section 172(c)(2) in the April 16, 1992 General 
Preamble and also in the May 10, 1995 Seitz memorandum with respect to 
the requirements of sections 182(b) and (c). In the May 10, 1995 Seitz 
memorandum EPA also noted that section 182(g), the milestone 
requirement of Subpart 2, which is analogous to provisions in section 
189(c), is suspended upon a determination that an area has attained. 
The memorandum, also citing additional provisions related to attainment 
demonstration and RFP requirements, stated

    Inasmuch as each of these requirements is linked with the 
attainment demonstration or RFP requirements of section 182(b)(1) or 
182(c)(2), if an area is not subject to the requirement to submit 
the underlying attainment demonstration or RFP plan, it need not 
submit the related SIP submission either.

1995 Seitz memorandum at 5.
    That the requirements for redesignation of an area require EPA to 
find that the improvement in air quality is due to permanent and 
enforceable emission controls does not undermine EPA's interpretation 
that when EPA determines an area is in attainment, the requirement for 
further emission reductions beyond that necessary for attainment is 
suspended for so long as the area remains in attainment. EPA does not 
contend that a determination of attainment is equivalent to a 
redesignation, which requires additional showings beyond the fact of 
attainment before changing the designation of an area from 
nonattainment to attainment. A determination of attainment merely 
suspends certain requirements for so long as the area remains in 
attainment. That permanent emission reductions are required for a 
redesignation does not indicate that Congress intended an area to keep 
reducing emissions beyond the attainment level until an area is 
redesignated. There is no statutory support for the proposition that an 
area must keep reducing emissions below the level needed for attainment 
until that area is redesignated. EPA's construction of the statute 
recognizes the public interest in reducing burdens on states and 
sources within states associated with adopting and implementing 
additional control measures that are no longer necessary to attain the 
NAAQS. EPA has construed the statutory provisions as not requiring 
certain additional emission reductions above and beyond what was needed 
to attain the NAAQS.
    EPA again notes that it has already approved a demonstration of 
reasonable further progress for the SJV. In the context of considering 
whether a determination of attainment suspends the contingency measures 
requirement of section 172(c)(9), however, EPA concludes that the RFP 
requirements of sections 172(c)(2) and 189(c) would also be suspended 
for so long as the SJV remains in attainment, had they not already been 
approved.
    Comment 5: The commenter contends that contingency measures are 
needed to ensure both reasonable further progress and attainment. 
Waiver of the requirement for these measures in section 172(c))(9) was 
premised on the argument that the RFP requirement of section 172(c)(2) 
was tied to attainment and thus with an attainment finding there was no 
longer a purpose for contingency measures. The commenter asserts that 
because the RFP requirements of section 189(c)(2) cannot be waived for 
PM-10 nonattainment areas, the contingency measure requirements of 
section 172(c)(9) continue to have purpose. The commenter claims that 
they are needed as interim, stop gap measures to protect public health 
pending the SIP revisions required under section 189(c)(3). See 59 FR 
42015.
    Response: CAA Section 172(c)(9) provides that SIPs in nonattainment 
areas:

    Shall provide for the implementation of specific measures to be 
undertaken if the area fails to make reasonable further progress, or 
to attain the [NAAQS] by the attainment date applicable under this 
part. Such measures shall be included in the plan revision as 
contingency measures to take effect in any such case without further 
action by the State [or EPA].

This requirement is referred to as ``the contingency measures'' 
requirement, and is inextricably tied to the attainment and reasonable 
further progress requirements. Where sufficient progress has been made 
based on existing controls so that an area has already achieved 
attainment by the attainment date, it has no need to rely on 
``contingency measures'' to come into attainment by the attainment 
date, or to assure progress towards attainment.
    We have thus interpreted the contingency measures requirement of 
sections 172(c)(9) (and 182(c))(9) in subpart 2 of part D) as no longer 
applying when an area has attained the standard because those 
``contingency measures are directed at ensuring RFP and attainment by 
the applicable date.'' 57 FR at 13564; May 10, 1995 Seitz memo at 5-6. 
As explained at length in the responses to comments above and in the 
memoranda and rulemakings cited above, the requirements for RFP and 
attainment demonstrations no longer apply once an area has attained the 
standard. Thus it follows that the requirement for contingency measures 
to be triggered in the event RFP or attainment is not reached is also 
suspended for as long as the area attains the standard. As EPA stated 
in its Addendum to the General Preamble for Serious PM-10 Areas, 
``[s]ection 172(c)(9) requires that SIP's provide for the 
implementation of specific measures to be undertaken if the 
Administrator finds that the nonattainment area has failed to make RFP 
toward attainment or to attain the primary NAAQS by the applicable 
statutory deadline.'' 59 FR 42014-42015 (August 16, 1994). Where the 
area has attained the standards, as EPA has shown in responses to 
comments above, the attainment demonstration requirements and RFP 
requirement under section 189(c)(1) and (2) are suspended, and thus the

[[Page 63647]]

contingency measure requirements of section 172(c)(9) are also 
suspended.
    The commenter is incorrect in its assertion that the RFP provisions 
under section 189 remain applicable despite a determination that the 
area has attained the standards. As EPA has demonstrated in its 
response to comment 4 above, once the area has attained the standards, 
the RFP milestone requirements in section 189 are suspended for so long 
as the area remains in attainment. Thus no contingency measures are 
required to assure those requirements are met. Because EPA is 
finalizing its determination that the SJV area has attained the 
standards, it is also finalizing its determination that the requirement 
for contingency measures under section 172(c)(9) is suspended for so 
long as the area remains in attainment.

C. New Particulate Matter (PM) NAAQS

    Comment 6: The commenter argues that the most troubling 
implications of EPA's proposed finding is EPA's proposal to revoke the 
PM-10 standards altogether and eliminate monitors in areas that are 
found to be in attainment. The commenter contends that the 
reasonableness of EPA's Clean Data Policy is premised in part on the 
assurance of the Clean Air Act that EPA will eventually demonstrate 
that air quality has been permanently resolved due to the controls 
being implemented and that contingency measures will be in place as 
part of a plan to maintain clean air once an area has been redesignated 
to attainment. The commenter argues that under EPA's then current 
proposal for coarse PM, these assurances will be eliminated. The 
commenter states that EPA proposes to revoke the PM-10 standard 
``everywhere except in areas where there is at least one monitor that 
is located in an urbanized area with a minimum population of 100,000 
people and that violates the 24-hour PM-10 standard based on the most 
recent three years of data.'' 71 FR at 2674. The commenter further 
states that, with the proposed attainment finding, EPA is making the 
determination that the PM-10 standard will be revoked in the Valley 
without the Act's protections. The commenter is also concerned about 
the potential for EPA to refuse to consider data collected by monitors 
in rural areas. The commenter believes that EPA should provide an 
explanation as to why its determination is reasonable when there will 
be no safety net to recover from the decision if EPA is wrong.
    Response: The commenter's concerns are misplaced. First, EPA's 
responses to comments above indicate that its decision is reasonable, 
in accordance with its prior interpretations of the CAA, and in 
accordance with the statute. EPA reiterates that a determination of 
attainment results merely in a suspension of requirements for so long 
as the area remains in attainment. If the area violates the standard, 
then the requirements and protections of the Act again apply to ensure 
that the area attains and makes reasonable further progress towards 
attainment.
    Second, as noted above, on September 21, 2006, the EPA 
Administrator signed a final rulemaking which, among other things, 
revoked only the annual PM-10 standard, but left intact the 24-hour PM-
10 NAAQS. The EPA did not finalize its proposal to revoke the 24-hour 
PM-10 NAAQS. The final rulemaking did not revoke any designations under 
the 24-hour PM-10 standard, and all requirements for the 24-hour 
standard and all designations under that standard remain in place. 
Based on the most recent three years of data, all areas that monitored 
nonattainment for the annual standard also monitored nonattainment for 
the 24-hour standard. Thus the commenter is incorrect in contending 
that the determination of attainment would relieve the SJV of the 
protections of the PM-10 NAAQS. Should EPA determine that the SJV 
violates the 24-hour PM-10 NAAQS, it would again become subject to any 
requirements that had been suspended during its period of attainment. 
In addition, the area would still retain the incentive to be 
redesignated to attainment for the 24-hour `PM-10 NAAQS in order to be 
relieved of nonattainment NSR offset requirements and to avoid further 
attainment planning requirements should the area monitor a violation of 
the standard in the future, and the provisions for a maintenance plan 
pursuant to CAA sections 107(d)(3)(E) and 175A would still apply to any 
redesignation request. Thus these assurances of and motivation for 
continued attainment are not eliminated, and the ``safety net'' cited 
by the commenter remains in place.
    The commenter also cites to a portion of the proposed rule on 
Ambient Air Monitoring which discusses a five-part suitability test to 
determine whether potential PM-10-2.5 monitoring sites were suitable 
for comparison to the proposed NAAQs. 71 FR 2710, 2736 (January 17, 
2006). In the final monitoring rule signed September 27, 2006 and 
available at http://www.epa.gov/air/particles/actions.html, EPA is not 

adopting the five-part suitability test or the proposed PM-10-2.5 
monitoring network design. EPA had proposed the five-part suitability 
test along with certain minimum monitoring requirements and monitor 
placement criteria for the primary purpose of determining compliance 
with the proposed PM-10-2.5 particulate NAAQS. EPA proposed as the 
indicator for the NAAQS any ambient mix of PM-10-2.5 that is dominated 
by resuspended dust from high-density traffic on paved roads and PM 
generated by industrial sources and construction sources, but excluded 
any ambient mix of PM-10-2.5 that is dominated by rural windblown dust 
and soils and PM generated by agricultural and mining sources. The 
proposed level for the PM-10-2.5 NAAQS was selected so as to be of 
equal stringency to the 24 hour PM-10 NAAQS. However, in its recent 
rule revising the NAAQS EPA stated that it is not adopting the proposed 
PM-10-2.5 standard and instead, will be retaining the current 24 hour 
PM-10 standard. Therefore, EPA also did not adopt the proposed PM-10-
2.5 monitoring network design, including the five-part suitability test 
to which the commenter cites above. Thus the commenter's concerns about 
this aspect of the rule have not been realized.

D. EPA Policy on Special Purpose Monitoring Data

    Comment 7: The commenter states that EPA's use of an August 22, 
1997 memorandum from John Seitz on the use of special purpose 
monitoring data is based on an illogical reading and is an insufficient 
substitution for a reasoned determination. The commenter states that 
nothing in the CAA provides for this intermediate step of an attainment 
determination to be made independently of a redesignation under CAA 
section 107(d)(3)(E). The commenter contends that to the extent such a 
determination can be defended, it is subject to the rational basis 
standard of the Administrative Procedures Act. The commenter cites 
language from the 1997 Seitz memorandum that discusses the types of 
data EPA must consider before redesignating an area from nonattainment 
to attainment and concludes that the Agency cannot reasonably ignore 
data that falls short of specific part 58 requirements without 
explaining why those requirements undermine the validity of the data.
    Response: The commenter contends that an ``attainment determination 
is a beast of EPA's own creation'' and that it must be defended on a 
rational basis. In fact, attainment determinations have a basis in the 
statute: see e.g., section

[[Page 63648]]

107(d)(3)(E)(i), as well as sections 179(c), 188(b)(2) and 181(b)(2), 
but there is nothing that restricts EPA to making determinations of 
attainment in the context solely of those provisions. Indeed, as noted 
earlier, both the 9th and 10th U.S. Circuit Courts of Appeals have 
upheld EPA's authority to make attainment determinations outside the 
context of redesignation proceedings, and have also upheld EPA's 
interpretation of the statutory consequences of such determinations. 
Sierra Club v. EPA, 99 F.3d 1551 (10th Cir. 1996), Our Children's Earth 
Foundation v. EPA, No. 04-73032 (9th Cir. June 28, 2005 (memorandum 
opinion). Nothing in the Act compels EPA to wait until an area meets 
all the requirements for redesignation before EPA makes a determination 
that the area is in attainment with the standard with the effect that 
the requirements for certain statutory provisions relating to 
attainment are suspended by their own terms. Indeed, section 179(c) of 
the Act requires EPA to make an attainment determination within six 
months after an area's applicable attainment date whether or not EPA 
has made a finding with respect to redesignation. EPA's interpretation 
of the Act's provisions not to require, once attainment has been 
reached, certain plan submissions whose purpose is to assure 
attainment, is not at odds with the requirements for redesignation. 
EPA's rationale for issuing attainment determinations is set forth at 
length in the responses to comments on the Clean Data Policy, above. In 
making determinations of attainment, which are subject to notice and 
comment rulemaking, EPA is governed by the Clean Air Act and its 
regulations.
    Similarly, in identifying the data that should be considered in 
making a determination of attainment, EPA is subject to regulatory 
provisions that set forth criteria defining what constitutes an 
adequate monitoring schedule, methodology, and quality assurance for 
data that will justify reliance upon it. 40 CFR 58.14 applies to 
Special Purpose Monitors (SPMs), and requires that if intended to be 
used for purposes of demonstrating attainment or nonattainment, they 
must meet the requirements for State and Local Air Monitoring Stations 
(SLAMS) set forth in 40 CFR 58.13 and 58.22 as well as in appendices A 
and E of part 58. While EPA cited to the Seitz memorandum in its 
proposal, EPA is not, as commenters contend, hiding behind a non-
binding policy memorandum. Rather, that memorandum cited to the 
regulations applicable to data from special purpose monitors intended 
for use in attainment determinations. These regulations are designed to 
ensure that the data is accurate and reliable enough to be the basis 
for a formal determination as to whether an area has attained the 
relevant standard. The 1997 Seitz memorandum states that ``[the] Agency 
policy on the use of special purpose monitoring data for any regulatory 
purpose, with the exception of fine particulate matter data (PM-2.5) is 
that all quality assured and valid data meeting 40 CFR part 58 
requirements must be considered within the regulatory process.'' 1997 
Seitz memorandum at 1. EPA's regulations under 40 CFR part 58 provide 
for quality assurance and control requirements to ensure that 
regulatory decisions are based on reliable and accurate information.
    Conversely, it follows that data that does not meet these quality 
assurance criteria should not be considered, since basing regulatory 
decisions on data that has not been shown to be reliable would not 
further the public interest nor be consistent with EPA regulations on 
special purpose monitors. See 40 CFR 58.14. As set forth below in other 
responses to comments, EPA's decision to consider data from monitors 
that meets quality assurance criteria and its concomitant decision to 
exclude data that does not meet these criteria is based on its 
regulations, has a rational basis, and is designed to result in 
determinations that reflect accurate and reliable data.
    Here, the data from certain SPMs did not meet the quality assurance 
requirements of part 58, and therefore were not included for 
consideration in the determination of attainment. If in the future 
additional data that has been quality assured demonstrate that the area 
is in fact not attaining the standard, EPA will withdraw its 
determination of attainment. Until that time, there is no compelling 
reason for EPA not to proceed with an attainment finding based on all 
quality assured data where such data demonstrates that the SJV has 
attained the PM-10 standard.
    In EPA's Revisions to Ambient Air Monitoring Regulations, a final 
rule signed on September 27, 2006, EPA issued revised regulations 
concerning SPMs, and clarified that data from such monitors would not 
be used for attainment/nonattainment determinations if the monitors had 
not met the requirements of appendix A.
    Section 58.20(b) of the revised regulation provides in part:

    [a]ny SPM data collected by an air monitoring agency using a 
Federal reference method(FRM), Federal equivalent method (FEM), or 
approved regional method (ARM) must meet the requirements of section 
58.11, section 58.12, and appendix A to this part or an approved 
alternative to appendix A to this part * * *

    Section 58.20 (c) provides that:

    [a]ll data from an SPM using an FRM, FEM or ARM which has 
operated for more than 24 months is eligible for comparison to the 
relevant NAAQS, subject to the conditions of section 58.30, unless 
the air monitoring agency demonstrates that the data came from a 
particular period during which the requirements of appendix A or an 
approved alternative, appendix C, or appendix E were not met in 
practice.

Thus EPA's new monitoring regulations make plain that SPM data from a 
period during which appendix A is not complied with are not eligible 
for comparison to the NAAQS and EPA action in this case is consistent 
with that requirement.

E. Adequacy of the SJV Monitoring Network

    One commenter and numerous individual citizens raised a number of 
issues regarding the adequacy of the PM-10 monitoring network in the 
SJV. In a final rule approving the serious area PM-10 attainment plan 
for the SJV, EPA evaluated the adequacy of this network and concluded 
that it meets all applicable statutory and regulatory requirements and 
is adequate to support the technical evaluation of the PM-10 
nonattainment problem in the plan. 69 FR 30006, 30032-30033. EPA 
supported this conclusion in a technical support document accompanying 
the final rule, ``Evaluation of the Adequacy of the Monitoring Network 
for the San Joaquin Valley, California for the Annual and 24-Hour PM-10 
Standards''; Bob Pallarino, EPA Region 9, Air Division; September 22, 
2003 (2003 TSD). Nevertheless, EPA responds below to the specific 
comments raised regarding the network in connection with its proposed 
attainment determination for the SJV.
    Comment 8: The commenter states that CAA Section 110(a)(2)(B) 
requires States to establish appropriate air monitoring networks and 
that appendix D of 40 CFR part 58 identifies a minimum of six 
objectives that a SLAMS network should be designed to meet, as well as 
spatial representativeness criteria in developing the network. The 
District fails to address all six criteria in its annual Monitoring 
Network Reports (leaving out monitoring for regional pollutant 
transport and for impacts on rural and remote places) and the existing 
monitors represent only two of the six spatial

[[Page 63649]]

scales established in the regulations when three are required. Since 
the District fails to meet these basic requirements, EPA should address 
the adequacy of the monitoring network before making an attainment 
determination, including whether system audits were conducted as 
required by 40 CFR 58.2.5 (sic). EPA's only evaluation of the network 
was in the 2003 TSD in which EPA identified several deficiencies in the 
Valley's PM-10 monitoring network but signed off on the network in 
spite of the deficiencies.
    Response: Pollutant monitoring networks are designed to serve a 
number of purposes. While the primary purpose of a monitoring network 
is to determine an area's attainment status with regard to the NAAQS, 
there are a variety of other purposes networks serve, including 
determining maximum concentration locations; determining the 
effectiveness of air pollution control programs; evaluating the effects 
of air pollution levels on public health; tracking the progress of 
SIPs; providing dispersion modeling support; developing responsible, 
cost-effective control strategies; reconciling emission inventories; 
and developing air quality trends.\5\
---------------------------------------------------------------------------

    \5\ ``SLAMS/NAMS/PAMS Network Review Guidance'' EPA-454/R-98/
003, March 1998, section 1.0.
---------------------------------------------------------------------------

    The six monitoring objectives \6\ in EPA's regulations were 
developed to assist in designing monitoring networks to meet these 
various objectives. Clearly, monitoring to ``determine the welfare-
related impacts in more rural and remote areas (such as visibility 
impairment and effects on vegetation)'' or monitoring to assess 
regional transport of pollution are not directly related to determining 
whether or not an area is in attainment of the NAAQS. These are 
important objectives in terms of maximizing the utility of the 
monitoring network. However, when determining whether the SJV is 
attaining the PM-10 NAAQS, it is more important to demonstrate that the 
PM-10 network has monitors sited to capture the maximum concentrations 
expected to occur in the Valley and the representative concentrations 
of PM-10 throughout the area that the population of the SJV are 
breathing. As discussed in the 2003 TSD, the SJV PM-10 SLAMS network 
meets the two primary and most important objectives by siting most of 
its monitors to assess representative concentrations in areas of high 
population and monitoring in the area where the maximum PM-10 
concentrations are expected to occur. Thus the fact that the District 
did not address the two objectives above is not a significant factor in 
determining whether the SJV is in attainment of the PM-10 NAAQS.
---------------------------------------------------------------------------

    \6\ The six monitoring objectives as discussed in 40 CFR part 
58, appendix D, section 1 are (1) to determine highest 
concentrations expected to occur in the area covered by the network; 
(2) to determine representative concentrations in areas of high 
population density; (3) to determine the impact on ambient pollution 
levels of significant sources or source categories; (4) to determine 
general background concentrations; (5) to determine the extent of 
regional transport among populated areas; and in support of the 
secondary standards; and (6) to determine the welfare-related 
impacts in more rural and remote areas (such as visibility 
impairment and effects on vegetation).
---------------------------------------------------------------------------

    The commenter states that EPA regulations at 40 CFR part 58, 
appendix D, require networks to use at least three spatial scales \7\ 
in establishing a monitoring network. However, the regulations do not 
in fact require the use of any minimum number of spatial scales for PM-
10 SLAMS or National Air Monitoring Station (NAMS) \8\ networks. 
Section 1 of appendix D discusses the relationship between monitoring 
objectives and spatial scales of representativeness. As our regulations 
state in this section, ``[p]roper siting of a monitoring station 
requires precise specification of the monitoring objective which 
usually includes a desired spatial scale of representativeness.''
---------------------------------------------------------------------------

    \7\ See 40 CFR part 58, appendix D, section 1, for a discussion 
of spatial scales and their applicability in monitoring network 
design.
    \8\ The NAMS area subset of the SLAMS ambient air quality 
monitoring network.
---------------------------------------------------------------------------

    Table 1 of appendix D ``illustrates the four basic monitoring 
objectives and the scales of representativeness that are generally most 
appropriate for that objective.'' Emphasis added. Appendix D, section 
1, table 1. It is clear from this language that EPA did not intend to 
dictate specific spatial scales for each objective. However, it is 
important to ensure that the spatial scale of the site is appropriate 
for the monitoring objective that site is intended to meet. For 
example, a site that is intended to represent typical population 
exposure should be a neighborhood or urban scale site, not a microscale 
site. While a microscale site can be used to monitor for highest 
concentration, a middle or neighborhood scale site would also satisfy 
this monitoring objective.\9\
---------------------------------------------------------------------------

    \9\ While Table 6 in 40 CFR part 58, appendix D, section 5 could 
be interpreted to mean that three spatial scales are required for 
PM-10 NAMS sites, EPA's purpose here was to summarize the spatial 
scales which would be appropriate for NAMS sites, i.e. microscale, 
middle scale, and neighborhood scale sites are appropriate scales 
for PM-10 NAMS sites, but urban and regional scale sites are not. 
This is because the objectives for NAMS sites are to monitor in 
areas where the pollutant concentration and population exposure are 
expected to be the highest. Furthermore, EPA's recently signed rule 
revising the monitoring regulations at 40 CFR part 58, reiterates 
EPA's intention that urban and regional scales are not appropriate 
for PM-10 monitoring and the most important spatial scales for 
monitoring PM-10 are the middle and neighborhood scales.
---------------------------------------------------------------------------

    With respect to the system audit programs described in 40 CFR part 
58, appendix A, section 2.5, it is important to note that this type of 
audit, commonly referred to as a technical system audit (TSA, is a 
qualitative review of an agency's overall air monitoring operations 
designed to determine whether what the monitoring organization says is 
going to be performed in its quality management plan, quality assurance 
project plan, and standard operating procedures are performed as 
specified. A TSA is required to be ``on site'' in the sense of taking 
place at the monitoring organization facilities, either at one or more 
locations where monitoring activities are performed or where 
monitoring-related documents and records are kept, but it need not 
involve a visit to an actual monitoring site. When a discrepancy is 
identified, EPA asks the monitoring organization to correct the 
discrepancy and tracks the monitoring organization's efforts until the 
correction is made. Significantly, EPA does not disqualify any data 
already collected based on the results of a TSA, although the 
monitoring organization in principle might do so itself. See ``Quality 
Assurance Handbook for Air Pollutant Measurement Systems, Volume II, 
Part 1, section 15 (EPA-454/R-98-004, August 1998) and ``EPA 
Requirements for Quality Assurance Project Plans'' (EPA/240/B-01/003 
March 2001) at B-4.
    In contrast, the measurement quality checks described in appendix 
A, sections 3.1, 3.2, 3.3 and 3.4, are quality control checks in which 
quantitative data generated by quality control samplers or independent 
standards are compared against the routine monitors operated by the air 
monitoring agency in order to evaluate instrument performance or 
laboratory procedures. Id. at B-3. When determining whether data 
generated by air quality monitors can be considered to be valid and 
accurate for the purpose of determining whether an area has attained 
the NAAQS, measurement quality checks are critical.
    As a mechanism for helping to ensure that data generated by air 
quality monitors is valid and accurate and thus suitable for 
determining whether an area has attained the NAAQS, it is the 
measurement quality checks that are most important. These checks create 
an incentive for continuous attention to

[[Page 63650]]

proper operation and maintenance of each monitor, can identify problems 
with specific monitors so that the problems can be corrected, and 
provide a basis for the monitoring organization to disqualify data 
already collected if specific audit findings are found to be outside of 
acceptable limits. EPA discusses these evaluations with respect to the 
SJV monitoring network below in response to comment 13.
    EPA Regional Offices are required by appendix A to perform TSAs of 
State reporting organizations once every three years. A reporting 
organization, as defined in 40 CFR part 58, appendix A, section 3.0.2, 
is a State, subordinate organization within a State, or other 
organization that is responsible for a set of stations that monitors 
the same pollutant and for which data quality assessments can be 
pooled. States must define one or more reporting organizations for each 
pollutant such that each monitoring station in the State SLAMS network 
is included in one, and only one, reporting organization.
    California has designated four reporting organizations within the 
State: CARB, the South Coast Air Quality Management District, the Bay 
Area Air Quality Management District, and the San Diego Air Pollution 
Control District. All other air quality districts in the State, 
including the San Joaquin Valley Air Pollution Control District, are 
included in the CARB reporting organization. CARB and the Districts in 
its reporting organization represent one of the largest and most 
experienced air quality reporting organizations in the nation.
    EPA has audited certain aspects of the CARB monitoring program 
recently. EPA's Office of Air Quality Planning and Standards (OAQPS) 
performed measurement quality checks and TSAs of the CARB PM 
laboratories in October 2002 and March 2004. These evaluations and 
audits confirmed that the laboratories used by CARB and the San Joaquin 
Valley Air Pollution Control District for weighing PM filters were 
operating consistently with appendix A requirements. No deficiencies 
for the PM lab were noted. Overall good laboratory practices were 
observed during this TSA. See Technical Memorandum on CARB Laboratory 
Audit to Jim Homolya, EPA, OAQPS, from Michael S. Clark, National Air 
and Radiation Environmental Laboratory, February 26, 2003 and Technical 
Memorandum on CARB Laboratory Audit to Jim Homolya, EPA, OAQPS, from 
Eric Boswell, National Air and Radiation Environmental Laboratory, 
dated April 22, 2004. Moreover, CARB Quality Assurance Section also 
conducts its own internal audits of the PM laboratory.
    In October 2004, EPA Region 9 performed a technical evaluation of 
the CARB `Through-the-Probe' (TTP) audit program for gaseous pollutants 
to establish system equivalence between the CARB and EPA TTP programs 
and to independently review the CARB TTP program. See ``Review of 
California Air Resources Board's `Through-the-Probe' Audit Program'', 
October 6-7, 2004. The TTP audit is a procedure for performing 
measurement quality checks of gaseous analyzers and is the primary tool 
used by CARB to fulfill its audit responsibility for these types of 
analyzers in 40 CFR part 58, appendix A, section 3.2. While EPA's audit 
of the CARB TTP program focused on gaseous pollutant performance 
audits, the audit served as an on-site TSA with respect to CARB's 
corrective action procedures used by CARB following a performance audit 
failure of a PM-10 monitor, as CARB's corrective action procedures are 
common to all pollutants including PM-10. We have since evaluated the 
CARB TTP program three additional times in June 2005, October 2005 and 
April 2006. See memorandums to Catherine Brown, USEPA Region 9 from 
Kevin Woodruff, ESAT TTP Task Manager, dated July 8, 2005, May 8, 2006, 
and May 18, 2006.
    CARB has conducted its own TSA-like assessment of the District's 
monitoring program. CARB's oversight includes routine annual 
performance audits of PM-10 SLAMS monitors, verification that sites 
meet EPA siting criteria and periodic assessments of the District's air 
monitoring program. See the CARB's Annual Data Quality Reports and the 
San Joaquin Valley Air Pollution Control District Program Review, 
Report of Findings and Recommendations, by CARB Stationary Source 
Division, October 2005. Audit information for individual monitoring 
stations in the CARB reporting organization is available at the CARB 
Web site http://www.arb.ca.gov/qaweb/. The Web site includes maps of 

each site, site photographs, and a detailed survey of the physical 
parameters and conditions at each site. These activities, while 
performed by CARB, are very similar to the field operation portion of 
EPA's TSAs.
    Region 9 continues to keep informed of CARB and its Districts' 
monitoring program developments through our ability to review revisions 
to quality assurance (QA) documents and the other information described 
above on the CARB QA Web site. EPA believes that these activities as 
well as the on-site activities described above, EPA's evaluation in the 
2003 TSD, and the performance audits described below, can and should be 
considered to substantially meet the requirements of appendix A and are 
sufficient to ensure that the data produced by the PM-10 SLAMS network 
operating in the SJV is adequate for EPA to base our finding of 
attainment.
    Furthermore, the District and CARB annually certify that the data 
in EPA's Air Quality System (AQS) database is correct and accurate. EPA 
also annually reviews the precision and accuracy data (precision and 
accuracy data are discussed in more detail in the response to comment 
13 below) submitted along with the PM-10 concentration data by CARB and 
the District.
    As stated above, in the 2003 TSD EPA determined that the PM-10 
monitoring network for the SJV, which includes monitors operated by 
both CARB and the District, meets all applicable statutory and 
regulatory requirements. EPA Region 9 uses the following four criteria 
to evaluate whether agencies operate approvable networks: (1) The SLAMS 
network used EPA approved samplers to collect data, (2) the agency has 
a quality assurance plan in place that meets EPA requirements, (3) the 
agency operates the required number of monitoring sites designated as 
NAMS, and (4) the monitoring network is designed in accordance with the 
requirements of 40 CFR part 58, appendices D and E. These criteria are 
based on requirements in 40 CFR part 58 and on EPA guidance 
documents.\10\
---------------------------------------------------------------------------

    \10\ These guidance documents include ``PM-10 SIP Development 
Guideline'', EPA-450/2-86-001, June 1987; ``Network Design and 
Optimum Site Exposure Criteria for Particulate Matter'', EPA-450/4-
87-009/ May 1987; ``Guidance For Network Design and Optimum Site 
Exposure For PM-2.5 and PM-10'', EPA-454/R-99-022, December 1997; 
``SLAMS/NAMS/PAMS Network Review Guidance'', EPA-454/R-98-003, March 
1998.
---------------------------------------------------------------------------

    The only deficiency in The District's PM-10 network that EPA has 
identified relates to the number of sites designated as NAMS. In the 
2003 TSD at 5, we stated:

    According to EPA regulations, the [District] should have a 
minimum of 11 sites designated as NAMS sites, based on the average 
PM-10 concentrations during the years 1999-2001 and the 2000 census 
population data. * * * The number of monitoring sites in the [SJV] 
designated as NAMS is less than that required in EPA regulations. 
However * * * EPA has been de-emphasizing the difference between 
NAMS and SLAMS sites. * * * EPA is planning to revise the 
regulations at 40 CFR part 58, Appendix D, which discusses the NAMS 
requirement, to eliminate the designation of sites as either NAMS or 
SLAMS.

[[Page 63651]]

    In footnote 3 in the 2003 TSD, EPA explained that:

    EPA, in partnership with State and local air agencies, has been 
developing a National Monitoring strategy which no longer makes a 
distinction between NAMS and SLAMS sites. The strategy, once 
codified in EPA regulations, will simply establish a certain minimum 
number of monitoring sites in a metropolitan area, still based on 
population and pollutant concentration severity. The current network 
in the [SJV] will easily meet these minimum requirements.

    At the time we evaluated the SJV PM-10 monitoring network, we 
believed, in light of the de-emphasis on the difference between NAMS 
and SLAMS sites, that it would be unreasonable to find the network 
inadequate because of this technical deficiency which EPA was planning 
to eliminate. In fact, in our final Ambient Air Monitoring rule signed 
on September 27, 2006 that amends 40 CFR part 58 we did eliminate the 
NAMS designation requirement completely. Elimination of the NAMS 
requirement does not affect the number of monitors operating in the PM-
10 network. Sites designated as NAMS simply convert to SLAMS sites. 
Based on the above, we believe the data produced by the SLAMS network 
is technically sound and can be used to determine the SJV's attainment 
status. EPA wants to emphasize, however, that the action today is 
simply an assessment of the data collected at the District's PM-10 
monitoring stations from 2003-2005, and continuing into 2006. This 
attainment determination does not preclude any future assessments of 
the PM-10 monitoring network, addition of new monitoring sites, or shut 
down of any existing sites.
    Comment 9: The commenter states that the monitoring network does 
not meet the basic objectives laid out by federal regulation and leaves 
vast portions of the Valley completely unmonitored. The commenter 
asserts that EPA must address this deficiency before making an 
attainment determination. The commenter states that the majority of the 
PM-10 monitoring takes place along the Highway 99 corridor which 
captures most of the SJV's major urban centers, but entirely overlooks 
the eastern and western portions of the SJV. The western portion of the 
SJV should be of particular concern to the District and EPA as it is an 
area of widespread poverty and environmental injustice, as well as 
being an area of intense agricultural activity.
    Response: We disagree with the commenter's contention that the 
network fails to meet the basic monitoring objectives described in 40 
CFR part 58, appendix D, section 1. EPA regulations do not prescribe 
the size of an area's PM-10 monitoring network or the exact placement 
of monitors. 40 CFR part 58, appendix D, section 1, ``SLAMS Monitoring 
Objectives and Spatial Scales'' states:

    \It should be noted that this appendix contains no criteria for 
determining the total number of stations in SLAMS networks * * *. 
The optimum size of a particular SLAMS network involves trade offs 
among data needs and available resources that EPA believes can best 
be resolved during the network design process.\11\
---------------------------------------------------------------------------

    \11\ See also ``SLAMS/NAMS/PAMS Network Review Guidance'' EPA-
454/R-98/003, March 1998, section 2.1.2.

    It is unreasonable and cost prohibitive to require a monitoring 
agency to operate a monitoring station in every location expected to 
have high levels of a particular pollutant. The District operates SLAMS 
in a variety of areas that represent typical emission scenarios in the 
SJV including urban areas of dense population, industrial areas, and 
rural areas dominated by agricultural emission sources. See 2003 TSD at 
5.
    The monitoring network in the SJV has both neighborhood and middle 
scale sites. As stated previously in this notice (see response to 
comment 8 and footnote 7), these spatial scales are the most important 
in monitoring for PM-10. Monitoring sites that are representative of 
middle scale impacts cannot only represent the area immediately around 
the monitoring site but also areas of similar emission characteristics. 
Similarly, neighborhood scale sites can represent not only the 
immediate neighborhood but also neighborhoods of similar types in the 
city or area. Furthermore, neighborhood stations provide the most 
relevant information about trends and compliance with standards because 
they often represent conditions in areas where people commonly live and 
work for periods comparable to those specified in the NAAQS. See 40 CFR 
part 58, appendix D, sections 2.8.0.4 and 2.8.0.5.
    Most of the monitors in the SJV network are neighborhood scale 
sites with the objective of assessing population exposure. Since the 
majority of the SJV's population resides in urbanized areas along the 
Highway 99 corridor and since many of the emission sources are mobile 
or traffic-related, we believe this is an appropriate focus of the 
monitoring network. 2003 TSD at page 5.
    The District also monitors in locations in addition to the Highway 
99 locations, e.g. Corcoran, Taft, and Hanford.\12\ Thus, the District 
network does represent the source types that make up the majority of 
emission sources in the western and eastern portions of the SJV. The 
monitoring locations at Corcoran and Hanford are both rural locations 
surrounded by agricultural sources of PM-10. Since it is not feasible 
for the District to monitor in every rural location, these sites can be 
viewed as representative of other unmonitored locations in the Valley.
---------------------------------------------------------------------------

    \12\ See ``State and Local Air Monitoring Network Report--2005'' 
San Joaquin Valley Unified Air Pollution Control District. Planning 
Division, August 2005.
---------------------------------------------------------------------------

    Comment 10: The commenter points out that back in the 1990s, there 
were at least four monitoring sites in what can be considered the rural 
west side. These sites, located at Los Banos, Five Points, Kern 
Wildlife Refuge, and Kettleman City, were all shut down in the mid-
1990s with little or no explanation, consultation with EPA or public 
notification, as required by 40 CFR 58.26(e). These monitors were 
mentioned in passing in the District's 1994 Air Monitoring Network 
Report as ``not necessary'' and ``resource intensive'' and were to be 
closed to ``redirect resources.'' The commenter notes that the Five 
Points monitor monitored sizeable violations until 1993, the year it 
disappeared from the District's network.
    Response: The public notification requirement in 40 CFR 58.26(e) 
cited by the commenter was part of the monitoring regulation revisions 
made to implement the PM-2.5 NAAQS (62 FR 38833 (July 18, 1997)) and 
applies only to that pollutant:

    After 3 years following September 16, 1997 or once a monitoring 
area has been determined to violate the NAAQS, then changes to an 
MPA monitoring network affecting the valuating locations shall 
require public review and notification.

``MPA'' stands for ``Monitoring Planning Area'' and ``means a 
contiguous geographic area * * * having a common area that is used for 
planning monitoring locations for PM 2.5'' Emphasis added. 40 CFR 58.1.
    Moreover, EPA generally defers to a State or local agency's 
judgment in determining which SLAMS to operate in a network as long as 
the overall monitoring objectives in our regulations are being met. 
However, EPA would object if an agency discontinued a design value site 
or a site with unique source characteristics that is violating the 
NAAQS.
    In 1993-1994 the District and CARB operated 18 monitoring sites in 
the

[[Page 63652]]

Valley. Three sites were shut down at the end of 1993: Los Banos, Kern 
Wildlife Refuge, and Five Points. Los Banos and Kern Wildlife Refuge 
were never in violation of the PM-10 NAAQS so the District's decision 
to shut them down for any of the reasons cited by the commenter would 
not have been questioned by EPA.
    The Kettleman City monitor continued to run until 1996. This 
monitor did record 5 exceedances of the 24-hour PM-10 NAAQS during the 
period 1990 to 1993 but was in attainment of the PM-10 NAAQS from 1994 
to 1996 when it was discontinued.
    While Five Points was a violating monitor, it was not unique in 
that there were other monitors in the Valley that operated in areas 
subject to the same type of agricultural emission sources. In the year 
that it was shut down there were significantly higher and more frequent 
exceedances of the NAAQS at the Corcoran monitoring site. Consequently, 
there was no restriction preventing the District from discontinuing it. 
In addition, because this site was in a largely uninhabited area it was 
not as useful as other sites in the network for assessing population 
exposure to PM-10 air pollution.
    The Corcoran monitoring site has always been one of the highest-
reading sites \13\ in the District's PM-10 network and that site has 
run continuously \14\ since the PM-10 NAAQS has been in existence. The 
Corcoran site is very similar to the Five Points site in terms of the 
surrounding land use (agricultural). During the period 1986 to 1993 the 
Five Points site recorded six exceedances of the 24-hour NAAQS, and 
only one year that exceeded the annual NAAQS (1988 with a 52 [mu]g/
m\3\). In comparison, during the same time period, Corcoran showed 21 
observed exceedances of the 24-hour NAAQS and exceeded the annual NAAQS 
every year during that time period (the maximum annual concentration 
was 70.2 [mu]g/m\3\ in 1991). The Corcoran site also monitors in an 
area where there is greater population, which makes it a more desirable 
site.
---------------------------------------------------------------------------

    \13\ The Corcoran site has had multiple PM-10 monitoring 
instruments in operation during its history, including three federal 
reference method (FRM) high volume samplers, a beta attenuation mass 
(BAM) analyzer, and a tapered element oscillating microbalance 
(TEOM) analyzer. At present, the site operates three FRM high volume 
samplers and a TEOM analyzer. The BAM and TEOM analyzers are not 
FRMs but have been designated as federal equivalent method (FEM) 
monitors by EPA. Two of the three FRM samplers have been designated 
by the District as the primary, or SLAMS, samplers for the Corcoran 
monitoring site. The third FRM is operated for quality control 
purposes.
    FRMs are manual samplers that pull air through a filter for 24 
hours (midnight to midnight). The filters are then weighed in a lab 
and a PM concentration is calculated based on the mass increase of 
the filter and the volume of air drawn through it. The two primary 
FRMs operate on a staggered one in six day schedule such that a 
sample is collected once every three days.
    \14\ The original Corcoran site was located on Van Dorsten 
Avenue and ran from 1986 to 1998. The current Corcoran site at 
Patterson Avenue began monitoring in 1997 and continues at this 
time. The Patterson Avenue site is approximately 1.1 miles north of 
the Van Dorsten Avenue site and has similar site characteristics.
---------------------------------------------------------------------------

    Comment 11: The commenter and other individual citizens state that 
the unmonitored (since mid-1990s) west side of Highway 99 is a large 
area of the SJV where monitoring is needed in order to understand the 
impacts of PM-10 pollution on the rural communities affected by intense 
agricultural operations and to fulfill federal monitoring objectives.
    Response: As stated previously, the District does monitor in areas 
of intense agricultural activity that are similar to and thus 
representative of conditions in other rural communities, including the 
western portion of the District. There may be site-specific reasons to 
monitor on the west side of the Valley for reasons beyond measuring 
attainment of the NAAQS, e.g. reporting more specific air quality 
information for people living and working in the western portion of the 
Valley for other health-related purposes. However, EPA believes that 
for the purposes of determining attainment, the current monitoring 
network, since it meets the requirements and objectives of the federal 
monitoring regulations, is representative of conditions throughout the 
Valley and thus is adequate for making an attainment determination.
    Comment 12: The commenter asserts that while the District claims 
that PM-10 levels in the SJV have greatly improved, these improvements 
come from a monitoring network that has gotten significantly smaller. 
In 1993, the commenter claims that there were 22 sites monitoring for 
PM-10 across a wider swath of the SJV, while today there are only 15 
sites concentrated along Highway 99. Given this narrow slice of the SJV 
under surveillance, it is unreasonable for EPA to declare the area in 
attainment of PM-10 without first making a meaningful evaluation of the 
adequacy of the monitoring network.
    Response: As stated above, EPA evaluated the SJV PM-10 monitoring 
network in 2003 and found it to be adequate under EPA regulations and 
guidance. 2003 TSD. That said, the District's claim that PM-10 levels 
in the Valley have improved is correct. The improvement in air quality 
is clearly evident from an examination of the air quality data for the 
last 19 years. The document ``United States Environmental Protection 
Agency Quicklook Criteria Parameters'' dated October 5, 2006 provides a 
summary of PM-10 data collected in the SJV since 1987.
    While the monitoring network has seen a reduction in the number of 
sites over this time period, from a high of 23 monitoring sites in 1990 
to the current 15 sites that have made up the District network since 
1999, most monitoring networks evolve over time and vary in size. Most 
of the sites shut down by the District during the past 19 years were in 
attainment of the PM-10 NAAQS for the previous three years. Some 
discontinued sites were replaced by new, nearby sites (Fresno, Drummond 
replaced Fresno, Olive; Fresno, 1st Street replaced Fresno, Cal State; 
Bakersfield, California Ave. replaced Bakersfield, Chester Street; Taft 
College replaced Taft, 10th Street; Corcoran, Patterson replaced 
Corcoran, Van Dorsten; Hanford, Irwin replaced Hanford, Lacey; Merced, 
M Street replaced Merced, E Street; Modesto, 14th Street replaced 
Modesto, City Center).\15\ Some sites were shut down and not replaced 
(Fresno Five Points, Kern Wildlife Refuge, Kettleman City, Madera 
Library, Madera Health Dept., Los Banos, Modesto I street, Crows 
Landing). Generally these sites were in attainment of the PM-10 
NAAQS.\16\ Other new sites were established where previously there were 
no monitors. (Fresno, Clovis; Bakersfield, Golden State Hwy.; Stockton, 
Wagner; Turlock). The following table summarizes the monitoring sites 
in the Valley that have been operational over the past 19 years and 
illustrates that the monitors in the current network are not less 
representative of air quality throughout the SJV than the network that 
existed in 1993.
---------------------------------------------------------------------------

    \15\ CARB recommends that Districts perform ``parallel 
monitoring'' when proposing to relocate a monitoring site. While 
parallel monitoring is not a required activity when relocating a 
site, parallel monitoring data is often the best way to determine if 
important monitoring objectives for the existing site will be 
satisfactorily continued at the replacement site. See the document 
``Site Relocation and Parallel Monitoring Guidelines'' June 1997, 
California Air Monitoring and Technical Advisory Committee.
    \16\ Two sites shut down were in violation of the 24-hour PM-10 
NAAQS. Fresno Five Points, which was discontinued in 1993, had 
recorded a single exceedance of 190 [mu]g/m\3\ in 1993, but had no 
exceedances in 1991 and 1992. Crows Landing in Stanislaus County, 
which was discontinued in 1991, had a single exceedance in 1990 of 
180 [mu]g/m\3\, but recorded no exceedances in 1989 or 1991.

[[Page 63653]]

--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                     Year
        Site        ------------------------------------------------------------------------------------------------------------------------------------
                       87     88     89     90     91     92     93     94     95     96     97     98     99     00     01     02     03     04     05
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fresno Olive            X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fresno Drummond                       X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fresno 1st St                                X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fresno Cal State        X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fresno Five Points      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Fresno Clovis                                       X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bakersfield Chester     X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bakersfield Golden                                                       X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Bakersfield CA Ave                                                       X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Oildale                 X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Kern Wildlife                         X      X      X      X      X
 Refuge
--------------------------------------------------------------------------------------------------------------------------------------------------------
Taft 10th Street        X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Taft College                                 X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Cocoran Van Dorsten     X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Corcoran Patterson                                                                     X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hanford Lacey           X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Hanford Irwin                                                     X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Kettleman City          X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Madera Library          X             X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Madera Health Dept.                   X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Los Banos                      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Merced E Street                X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Merced M Street                                                                                             X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Stockton Hazelton       X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Stockton Wagner                                                                        X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Modesto I Street                      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Modesto City Center     X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Modesto 14th Street                   X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Turlock                                                                  X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Crows Landing                  X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
Visalia                 X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X      X
--------------------------------------------------------------------------------------------------------------------------------------------------------
X indicates the site was operational in that year.
Source: EPA's AQS Database.

    Comment 13: The commenter states that, in addition to their failure 
to demonstrate the adequacy of the network, EPA and the District have 
also failed to provide records attesting to the proper functioning and 
maintenance of the particular monitors used to determine attainment. 
While EPA uses claims of improper maintenance to ignore data from 
continuous monitors, it never establishes that the data it is 
considering is in fact reliable and comes from a properly maintained 
network. The commmenter further claims that the record before EPA fails 
to demonstrate that the network complies with 40 CFR part 58 and 
therefore EPA must collect additional information as required by 
regulations and provide it to the public before it can cherry pick the 
data to be used for the attainment determination.

[[Page 63654]]

    Response: Contrary to the commenter's contention, the FRM data on 
which EPA is basing its attainment decision is reliable and from 
instruments that are properly functioning and maintained in accordance 
with 40 CFR 58 and its appendices. EPA's confidence in the data is 
based on records submitted by the State that demonstrate that the 
network operations which produced the data meet, or in some cases 
exceed, the requirements in our regulations at 40 CFR part 58.
    EPA and its regulations provide for different types of requirements 
to assure the quality of data, depending upon the types of equipment 
used to measure PM-10. There are two categories of instruments that can 
be used to measure PM-10 concentrations in the ambient air, manual 
reference method samplers and automated equivalent method or continuous 
analyzers.\17\
---------------------------------------------------------------------------

    \17\ All equipment designated by EPA as approved for NAAQS 
comparisons can be found in the document ``List of Designated 
Reference and Equivalent Methods'', USEPA, National Exposure 
Research Laboratory, July 26, 2006 available at the Web site http://www.epa.gov/ttn/amtic/files/ambient/criteria/ref0706.pdf
.

---------------------------------------------------------------------------

    A manual reference method sampler provides a 24 hour average 
concentration value for PM-10 in the ambient air. A manual reference 
method sampler uses a filter medium through which ambient air is drawn 
at a near constant flow rate for a period of 24 hours (midnight to 
midnight). This flow rate through the filter is an important parameter 
and must be recorded accurately. Monitoring the actual flow rate to 
verify that the designed flow rate is being maintained during the 24-
hour period is important because the inlet of the sampler will ensure 
the needed separation of particles 10 microns or less in diameter from 
larger particles only if the proper flow rate is maintained. Also, the 
flow rate measurement provides us with the total volume of air drawn 
through the filter during the 24-hour period. The total volume of air 
is needed to calculate the PM-10 concentration.
    The filters used in PM-10 manual reference method samplers are 
weighed in a laboratory before they are installed in the sampler and 
weighed again after air has been drawn through the sampler for 24 
hours. The pre-sampled mass of the filter is subtracted from the post-
sampled mass and the result is the total mass of PM-10 collected. This 
total mass is divided by the total volume of air to determine the 24 
hour average PM-10 concentration. In the best case a manual sampler can 
provide a 24 hour average concentration in about two days from the day 
a sample was collected. In practice and depending on a number of 
factors (e.g. how many filters the lab has to process, the distance 
between the laboratory and the monitoring site, on what day of the week 
a sample was taken) processing the filters in a laboratory and 
calculating the concentration can take a few weeks, on average.
    Automated equivalent methods or continuous analyzers, such as Beta 
Attenuation Mass (BAM) or Tapered Element Oscillating Microbalance 
(TEOM) monitors, use one of two alternative measurement approaches 
(beta ray attenuation or mass-dependent oscillation frequency) to avoid 
the need to collect PM-10 on a filter medium that must subsequently be 
weighed in a laboratory. Continuous analyzers report PM-10 
concentrations over short intervals in near real time. The analyzers 
can be (and typically are) configured to report the average 24 hour PM-
10 concentration just as a manual reference method does.
    As discussed elsewhere in this action, the SJV PM-10 SLAMS network 
consists of 15 monitoring sites using manual reference method samplers. 
These samplers operate on a once every six day schedule except for the 
site at Corcoran, which operates once every three days because it has 
two samplers operating on staggered once every six day schedules. 
Corcoran's sampling frequency is twice that of other sites in the SJV 
PM-10 SLAMS network because it is historically the highest reading PM-
10 site in the network.
    One of the goals in any data collection effort is to be able to 
quantify measurement uncertainty. Measurement uncertainties are the 
errors associated with the ambient air monitoring agency, including 
errors associated with the field, preparation and laboratory 
measurement phases. At each measurement phase, errors can occur, that 
in most cases are additive. Air quality monitoring agencies aim to 
control measurement uncertainty to an acceptable level through the use 
of various quality control and evaluation techniques. Two of the 
primary checks used to evaluate measurement uncertainty are precision 
and accuracy checks. We will discuss each of these procedures below in 
more detail. An important point to understand is that in addition to 
allowing an evaluation of the uncertainty in the data that has been 
collected, these checks can reveal equipment or procedural problems 
that can be corrected. They can also lead a monitoring agency to 
disqualify or withdraw data collected in a period before a check 
revealed a problem, on the reasonable assumption that the data was 
affected by the problem.
    EPA regulations at 40 CFR part 58, appendix A, section 3.0.1 states 
that ``All ambient monitoring methods or analyzers used in SLAMS shall 
be tested periodically, as described in this section, to quantitatively 
assess the quality of the SLAMS data.'' Precision checks are a 
measurement of mutual agreement among individual measurements of the 
same property usually under prescribed similar conditions, expressed 
generally in terms of standard deviation. There are different ways to 
determine the precision of PM-10 monitoring networks depending on 
whether the network utilizes manual reference methods or automated 
equivalent methods. Precision checks of manual and automated methods 
are addressed in 40 CFR part 58, Appendix A, sections 3.3 and 3.1, 
respectively.
    The SJV PM-10 SLAMS network is a subset of the larger California 
PM-10 SLAMS network.\18\ Section 3.3 of Appendix A discusses how to 
establish the precision of a PM-10 network made up of manual method 
samplers, which applies to the SJV PM-10 SLAMS network. The requirement 
is to operate a certain number of collocated monitoring sites, i.e., 
duplicate samplers, depending on the total number of samplers in the 
network: 1 collocated site for networks consisting of up to five sites, 
2 collocated sites for networks consisting of 6 to 20 sites, and 3 
collocated sites for networks of 20 or more sites. These collocated 
samplers must run on the same days as the primary samplers and must be 
run on at least a once every six days schedule.
---------------------------------------------------------------------------

    \18\ For the purposes of EPA quality assurance requirements, the 
California PM-10 SLAMS network is defined as those PM-10 monitors 
designated as SLAMS in the CARB document ``California State and 
Local Air Monitoring Network Plan--2005'' Planning and Technical 
Support Division, Air Quality Branch, October 2006 with the 
exception of PM-10 SLAMS monitors operated by the South Coast AQMD, 
the Bay Area AQMD, and the San Diego APCD.
---------------------------------------------------------------------------

    The California State PM-10 SLAMS network consists of 97 monitoring 
sites and has five collocated sites located at Bakersfield, Visalia, 
Taft, Corcoran, and Sacramento. The first four of these listed 
collocated monitoring sites are located in the SJV. If the SJV PM-10 
network was evaluated separately from the rest of the State network, 
EPA regulations would only require two collocated precision sites. From 
this perspective, there are twice the number of collocated precision 
sites as required by EPA regulations. Each of these samplers will 
produce a pair of concentrations on a

[[Page 63655]]

given sampling day.\19\ These concentrations must be greater than 20 
[mu]g/m3 in order to be used in determining the precision of 
the network. According to the CARB QA manual, if concentrations are 
below 80 [mu]g/m3, the two paired values must be within 5 
[mu]g/m3 of each other, or further investigation and 
corrective action are required. If the concentrations are greater than 
80 [mu]g/m3 they must be within 7 percent of 
each other.\20\ These acceptance criteria are consistent with EPA 
criteria in the guidance document ``Quality Assurance Handbook for Air 
Pollution Measurement Systems, Volume II: Part 1, Ambient Air Quality 
Monitoring Program Quality System Development'', (EPA-454/R-98-004, 
August 1998).
---------------------------------------------------------------------------

    \19\ Because it operates on a one in three day sampling schedule 
and is also a collocated precision site, the Corcoran monitoring 
site has three manual reference method samplers in operation, two 
that run concurrently and a third that runs on the staggered one in 
six day schedule that enables the site to produce data every three 
days.
    \20\ State of California Air Resources Board, Air Monitoring 
Quality Assurance, Volume I, Quality Assurance Plan, Monitoring and 
Laboratory Division, June 2005.
---------------------------------------------------------------------------

    EPA's QA guidance cited above provides a target for the system-wide 
precision performance, taken across all pairs of collocated data. EPA 
regulations at 40 CFR part 58, appendix A section 5.3 requires 95 
percent upper and lower probability limits be used to evaluate the 
collocated data. The target given in the guidance for the 95th 
percentile upper and lower limits for reporting organizations is 15 
percent. The annual precision summary statistics for the CARB PM-10 
SLAMS network meet these requirements as shown in the AQS Report ``P/A 
Reporting Organization Summary, AMP 240.''
    Establishing precision for automated equivalent method analyzers, 
such as BAM or TEOM monitors, consists of performing a bi-weekly one 
point precision check of an analyzer's operational flow rate. See 40 
CFR part 58, appendix A, section 3.1. The check is made using a flow 
rate transfer standard. The actual flow rate measured by the transfer 
standard and the indicated flow rate of the analyzer (the flow rate as 
measured by the analyzer's own flow rate meter) are reported to the AQS 
database. In the case of the automated equivalent analyzers operated by 
the District as special purpose monitors rather than as SLAMS monitors, 
these precision checks were not made in accordance with Appendix A 
section 3.1 and therefore EPA cannot have the same confidence in these 
data as we have in the SLAMS data. Without performing the precision 
checks, the District may have overlooked operational problems and 
allowed them to affect the data from the special purpose monitors, and 
without the precision check data we have no way to evaluate the 
acceptability of the data.
    The other primary data quality control (QC) check for proper 
operation and maintenance of a monitor is the accuracy check. As with 
the precision checks, there are two different procedures for 
determining the accuracy of PM-10 monitors depending on whether we are 
checking a manual reference method or an automated equivalent 
(continuous) analyzer. These two procedures are addressed in 40 CFR 
part 58, Appendix A, sections 3.4 and 3.2 respectively.
    For the SJV PM-10 SLAMS network that used manual reference method 
samplers, the procedures in section 3.4 are used to determine accuracy. 
The procedure entails auditing the flow rate of each sampler annually 
such that 25 percent of the network \21\ is audited each calendar 
quarter. An independent auditor (i.e., not the person who regularly 
operates the sampler) using dedicated equipment (i.e., not the flow 
meter built into the sampler) audits the flow rate of the sampler and 
reports the actual flow rate and the indicated (sampler) flow rate. Two 
measurement quality parameters are calculated from these measurements: 
The percent difference in the flow rate measurements by the sampler's 
own flow rate meter and the auditor's dedicated flow rate meter, and 
the percent difference between the actual flow rate created by the 
sampler and the flow rate it was designed to have. Percent differences 
beyond acceptance limits can cause an incorrect measurement of PM-10 
concentrations. As the QA oversight agency, CARB's QA section performs 
the accuracy audits of the SJV PM-10 SLAMS network. These accuracy 
audits were performed by CARB as required by EPA regulations, and 
showed that the monitors were operating within the accepted control 
limits, i.e., the flow rates had not deviated enough from their design 
flow rates to require any corrective action on the part of the CARB or 
District monitoring staff. The results of the accuracy checks performed 
by CARB were submitted to EPA and are shown in the AQS Report ``P/A 
Reporting Organization Summary, AMP 240.'' The following table 
summarizes the accuracy results for the individual audits of the PM-10 
monitors in the SJV. The table shows the date of each audit (one per 
year) the differences in the flow rate measurement by the sampler's own 
flow rate meter (% Diff.) and the difference between the actual flow 
rate created by the sampler and the flow rate it was designed to have 
(% Diff. Design). This information shows that the monitors operated in 
the SJV PM-10 SLAMS network are performing within the acceptance 
criteria established by EPA in its QA guidance, which sets a target 
confidence interval for the 95th percentile upper and lower limits 
aggregated across the reporting organization of 20 percent, over a 
three year period. The CARB PM-10 SLAMS network easily meets this 
target based on the small differences shown in the table below. CARB's 
performance of these audits at the required frequencies and subsequent 
submittal of the results of the audits to EPA's AQS database meets the 
requirements of 40 CFR part 58, appendix A, section 3.4.
---------------------------------------------------------------------------

    \21\ In this case, 25 percent of the network applies to the 
California State PM-10 SLAMS network not the SJV PM-10 SLAMS 
network.

----------------------------------------------------------------------------------------------------------------
                                                                                                        % Diff.
                                                              Audit date      Sampler ID     % Diff.     design
----------------------------------------------------------------------------------------------------------------
Bakersfield-Golden........................................        6/4/2003            4121        0.0       -6.8
                                                                 7/13/2004            2456        6.8       -4.3
                                                                 10/5/2005            4121        5.3       -5.7
Clovis....................................................       6/18/2003            7380       -2.2        0.7
                                                                 7/29/2004            4040       -2.9        3.0
                                                                 11/7/2005            4040        0.3       -0.5

[[Page 63656]]

Corcoran-Patterson........................................        2/4/2003            1885       -2.6        7.0
                                                                  2/4/2003            4645        2.0       -2.0
                                                                  2/4/2003            4120       -8.0        3.0
                                                                 3/11/2004            1885       -0.7        0.5
                                                                 3/11/2004            4645        1.3       -1.5
                                                                 3/11/2004            4120       -0.7        0.5
                                                                 1/26/2005            1885        0.0       -0.7
                                                                 1/26/2005            4645        0.3       -1.0
                                                                 1/26/2005            4120        0.0        0.0
Fresno--Drummond..........................................       2/19/2003            4069        1.8       -2.2
                                                                 2/25/2004            4069       -2.3       -0.7
                                                                  3/1/2005            4069        4.3       -1.0
Hanford...................................................        2/4/2003            3048       -8.7       -2.5
                                                                 3/10/2004            1884        2.5       -1.3
                                                                 1/25/2005            1884        0.0       -3.8
Merced-M St...............................................        3/4/2003            4756       -5.3        7.5
                                                                 2/26/2004            4756        2.8       -3.5
                                                                 1/25/2005            4756        6.8       -8.0
Stockton--Wagner--Holt....................................       6/18/2003            3519        0.0        0.5
                                                                12/16/2004            3519        0.3       -2.2
                                                                11/28/2005            3519        4.8       -7.0
Taft......................................................        2/3/2003            8008      -11.7        7.2
                                                                  2/3/2003            7787       -5.4        6.5
                                                                 3/15/2004            8008       -9.0       -2.2
                                                                 3/15/2004            7787       -4.3        9.5
                                                                 3/14/2005            8008        5.2       -4.0
                                                                 3/14/2005            7787        3.6       -2.5
Turlock...................................................       3/11/2003            4161       -1.0       -1.8
                                                                  3/2/2004            4161       -8.5        6.3
                                                                 2/24/2005            3519        0.0       -3.8
Bakersfield-CA............................................       3/11/2003        20018176       -0.2        2.0
                                                                 3/11/2003        20018177        0.0        2.2
                                                                 3/16/2004        20018176       -2.2        3.8
                                                                 3/16/2004        20018177       -2.2        3.8
                                                                  3/8/2005        20018176        0.3       -0.3
                                                                  3/8/2005        20018177        1.0       -0.7
Fresno-First..............................................       6/16/2003        20018504        1.0        2.5
                                                                 7/28/2004            7660       -1.7        4.3
                                                                 7/26/2005            7660        0.7        1.5
Modesto-14th St...........................................        3/3/2003        20003727       -1.3       -3.0
                                                                  3/3/2004        20003727       -2.0        2.5
                                                                 2/23/2005        20003727        0.5        0.0
Oildale...................................................       3/12/2003        20004244        1.8       -0.3
                                                                 3/17/2004        20004244       -1.0        2.8
                                                                 3/10/2005        20004244        1.0       -1.0
Stockton-Hazelton.........................................      11/19/2003        20004282        1.0        0.5
                                                                12/16/2004        20004282        0.5        0.0
                                                                 12/1/2005        20004282        0.8       -1.8
Visalia...................................................       6/12/2003            7471        0.0        1.3
                                                                 6/12/2003            7678        1.3        0.0
                                                                 7/27/2004            7471       -1.7        4.7
                                                                 7/27/2004            7678       -1.4        4.3
                                                                 7/28/2005            7471        0.5        2.2
                                                                 7/28/2005            7678        2.8        0.0
----------------------------------------------------------------------------------------------------------------

    The accuracy audit for the automated equivalent analyzer is similar 
to that for manual reference methods. See 40 CFR part 58, appendix A, 
section 3.2.2. Like the audit performed for the manual reference 
methods the audit required for automated analyzers is a field audit. 
However, as discussed in this notice, no accuracy audits of the 
automated analyzers operated by the District were performed, and 
therefore EPA cannot assess the accuracy of these monitors. Because the 
flow-related components of the manual reference method samplers and of 
the automated equivalent analyzers are different in design and 
materials, the good performance of the manual samplers cannot be 
extrapolated to the automated analyzers.
    Additionally, annual certifications of quality control standards 
(e.g., a flow rate meter) are critical in order to insure that the 
checks and measurements being made are traceable to National Institute 
of Standards and Technology (NIST) standards. See 40 CFR part 58, 
appendix A, section 2.3.3. This certification is achieved by 
transferring the accuracy or authority of a primary standard to a 
field-usable standard. Also, calibrations of the internal flow rate 
meters of PM-10 samplers, which are generally performed annually or 
after sampler repairs, also ensure that these meters are functioning 
correctly. The following table lists the calibration dates of the 
internal flow rate meters of the SLAMS monitors in the SJV network. 
Calibrations of the flow rate meters are usually performed when a 
sampler is first installed at a site or after repair. While EPA 
regulations and guidance do

[[Page 63657]]

not specify a frequency for performing calibrations of flow rate 
meters, performing them annually regardless of whether the instrument 
required it demonstrates a good operation practice by the District and 
CARB.

------------------------------------------------------------------------
                                             Sample ID       Cal. date
------------------------------------------------------------------------
Bakersfield-Golden......................            4121       2/27/2003
                                                    2456       5/25/2004
                                                    4121      12/15/2004
Clovis..................................            7380       3/13/2003
                                                    4040       7/27/2004
                                                    4040       10/6/2005
Corcoran-Patterson......................            1885      10/28/2002
                                                    4645       1/30/2003
                                                    4120      10/28/2002
                                                    1885      11/12/2003
                                                    4645       12/9/2003
                                                    4120       12/9/2003
                                                    1885       10/5/2004
                                                    4645        1/5/2005
                                                    4120        9/2/2004
Fresno-Drummond.........................            4069      11/12/2002
                                                    4069       2/24/2004
                                                    4069      12/21/2004
Hanford.................................            3048      10/14/2002
                                                    1884      10/15/2003
                                                    1884        8/4/2004
Merced-M St.............................            4756       10/9/2002
                                                    4756       2/10/2004
                                                    4756       12/9/2004
Stockton-Wagner--Holt...................            3519       2/20/2003
                                                    3519       9/10/2004
                                                    3519       7/20/2005
Taft....................................            8008      11/19/2002
                                                    7787      10/25/2002
                                                    8008       2/26/2004
                                                    7778       2/26/2004
                                                    8008       8/18/2004
                                                    7778       8/18/2004
Turlock.................................            4161       1/23/2003
                                                    4161       7/16/2003
                                                    3519       2/23/2005
Bakersfield--CA.........................        20018176        3/7/2002
                                                20018177        3/7/2002
                                                20018176        3/9/2004
                                                20018177        3/9/2004
                                                20018176        6/3/2004
                                                20018177       6/16/2004
Fresno--First...........................        20018504       6/13/2003
                                                    7660       1/21/2004
                                                    7660       2/28/2005
Modesto--14th St........................        20003727       1/17/2003
                                                20003727       2/10/2004
                                                20003727       2/11/2005
Oildale.................................        20004244       2/27/2003
                                                20004244        1/8/2004
                                                20004244       1/31/2005
Stockton--Hazelton......................        20004282      11/12/2003
                                                20004282       12/9/2004
                                                20004282       11/9/2005
Visalia.................................            7471       5/20/2003
                                                    7678       5/20/2003
                                                    7471       5/20/2003
                                                    7678       5/20/2003
                                                    7471      11/24/2004
                                                    7678      11/24/2004
------------------------------------------------------------------------

[[Page 63658]]

    As detailed above, CARB has certified and submitted quarterly \22\ 
to EPA's AQS database, all the supporting QA data for the SJV SLAMS PM-
10 network, including data collected by the collocated precision 
network and all required audit data. This data shows that the operation 
and maintenance of the SLAMS network met the requirements of sections 
3.3 and 3.4 of Appendix A Part 58. By contrast the required number of 
precision checks and independent flow rate audits were not performed on 
the automated equivalent (BAM and TEOM) method monitors pursuant to 
sections 3.1.2 and 3.2.2 nor was data on the precision checks that were 
performed on the BAM monitors submitted to the AQS database as required 
by 40 CFR part 58, appendix A, section 4.1.\23\ Thus EPA is not, as the 
commenter contends, ``cherry picking'' data, but rather relying for its 
determination on data that has met the requirements for reliability 
under its regulations.
---------------------------------------------------------------------------

    \22\ EPA regulations require the submittal of precision and 
accuracy data on a quarterly basis, as it does for the pollutant 
concentration data. See 40 CFR 58.35 and 40 CFR part 58, appendix A, 
section 4.1.
    \23\ The District did perform some precision checks of the BAM 
monitor at Corcoran but these were considerably fewer than required 
in EPA regulations. See response to comment 15. Section 3.1.2 
requires the checks to be performed at a designated frequency and 
the data submitted to the AQS database.
---------------------------------------------------------------------------

F. Data Not Included in Determining Attainment

1. Data From September 3, 2004 High Wind Event
    Comment 14: The commenter questions the validity of waiving the 
September 3, 2004 exceedance as a Natural Events Action Plan (NEAP) 
\24\ event and states that there is no technical basis for ignoring the 
exceedance and that best available control measures (BACM) were not 
being implemented for the largest sources of dust in the Valley on that 
date. The commenter notes that removal of the flag puts the Valley 
right at the limit of violations allowed under the NAAQS and should 
make EPA wary to find the PM-10 problem solved in the Valley.
---------------------------------------------------------------------------

    \24\ See memorandum from Mary D. Nichols, Assistant 
Administrator for Air and Radiation to Regional Air Directors, 
``Areas Affected by PM-10 Natural Events,'' May 30, 1996.
---------------------------------------------------------------------------

    Response: The exceedance in question occurred at the Corcoran-
Patterson Avenue monitoring site. EPA notes in its proposed rule that 
``[t]his exceedance was flagged by CARB as a high wind natural event 
[and] EPA concurred with CARB's request to exclude this data from 
consideration in attainment findings on July 7, 2005.'' However, ``even 
if EPA had not concurred with the exclusion of this data, the Corcoran 
site would still attain the 24-hour NAAQS because the expected number 
of exceedances \25\ is less than or equal to one per year, averaged 
over the three year period 2003-2005.'' 71 FR 40952, 40954. In other 
words, EPA believes that it need not address here the issue of whether 
or not the September 3, 2004 exceedance should be flagged, because in 
any event the SJV would still be attaining the PM-10 standards. In 
addition, whether the SJV is ``at the limit'' of exceedances allowed 
under the NAAQS is not a criterion for making an attainment 
determination. Areas are either attaining or not attaining. EPA found 
that the area would still be attaining even if this exceedance were 
included, and on that basis determined that the area was in attainment. 
As noted above, EPA believes that preliminary data indicating a 
September 22, 2006 exceedance at the Corcoran monitor should also not 
be included in this attainment determination for the reasons stated 
previously relating to quality assured data and natural events.
---------------------------------------------------------------------------

    \25\ EPA determines attainment of the 24 hour PM-10 NAAQS based 
on the number of ``expected'' exceedances in a given year. Because 
most manual PM-10 samplers do not operate every day but on a one in 
six day schedule, EPA regulations at 40 CFR part 50, Appendix K 
require an adjustment to the observed or actual number of 
exceedances to account for days that are not sampled. In the 
simplest case, when a monitor operating once every six days, with 
100% data capture, records a single observed exceedance, that 
exceedance would be adjusted to six expected exceedances. In the 
specific case of the Corcoran monitoring site and its one in three 
day schedule, EPA calculated the expected exceedances, based on the 
single observed exceedance on September 3, 2004, to be three over a 
three year period which averages to one exceedance per year. This 
expected exceedance rate of one per year shows that the Corcoran 
site is still in attainment of the 24-hour NAAQS. See 40 CFR part 
50, Appendix K, section 3.1 for a complete discussion on how EPA 
adjusts data.
---------------------------------------------------------------------------

    Nevertheless, EPA notes that the attainment determination does not 
mean the air quality problem is solved in the SJV. In order to be 
redesignated as a PM-10 attainment area, the District and CARB will 
need to address CAA section 107(d)(3)(E) requirements. In addition, the 
SJV is nonattainment for the PM-2.5 and 8-hour ozone standards and will 
need to achieve substantial further reductions in pollution levels to 
attain these NAAQS. The commenter's implicit concern is that EPA's 
action will somehow allow the SJV to relax its efforts to reduce air 
pollution; however, EPA does not believe that is the case.
2. Data From BAM and TEOM Monitors
    Comment 15: The commenter states that there are four Beta 
Attenuation Mass (BAM) monitors (designated by EPA as federal 
equivalent methods and also referred to as ``special purpose 
monitors'') in the Valley that monitor PM-10 concentrations and that 
two of these monitors (Bakersfield-Golden State Highway and Corcoran-
Patterson Avenue) have recorded multiple exceedances of the Federal PM-
10 standard from 2003 to 2005. The commenter states that all valid data 
from special purpose monitors must be considered within the regulatory 
process and that EPA's rationale (that the District did not perform 
quality control checks every two weeks and that CARB did not perform 
independent field audits of the BAM sampler) for not considering data 
from the Corcoran BAM monitor is not adequate.
    Response: The District and CARB have operated automated equivalent 
(continuous) method monitors in the SJV at a number of PM-10 SLAMS 
sites. The following table summarizes the type (BAM or TEOM), location 
and history of operation of the PM-10 continuous monitors operated in 
the Valley.

------------------------------------------------------------------------
                                 BAM operational      TEOM operational
       Monitoring site               period                period
------------------------------------------------------------------------
Bakersfield Golden State Hwy  7/28/2005-8/8/2006..  8/27/2006-Present.
Corcoran....................  Before 1/1/2003-7/22/ 1/1/2003-3/31/2005.
                               06.                  8/24/2006-Present.
Fresno 1st Street...........  Before 1/1/2003-      Before 1/1/2003-
                               Present.              Present.
Stockton....................  NA..................  Before 1/1/2003-June
                                                     28, 2005.
Tracy.......................  10/25/2005-9/26/2006  10/1/2006-Present.
------------------------------------------------------------------------

[[Page 63659]]

    EPA regulations at 40 CFR part 50, appendix K, section 2.3 address 
the data requirements that must be met in order for EPA to determine 
the attainment status of a particular monitoring site. In general EPA 
needs three years worth of monitoring data in order to declare a site 
in attainment of the NAAQS. Of the four BAM monitors operated in the 
Valley, only Fresno 1st Street and Corcoran have been in operation long 
enough to have accumulated three years of data.\26\ The Bakersfield-
Golden State Highway site operated a BAM monitor from July 28, 2005 to 
August 8, 2006. The BAM was replaced by a TEOM monitor on August 27, 
2006. The Tracy site operated a BAM monitor from October 26, 2005 to 
September 26, 2006. The Tracy BAM was replaced by a TEOM monitor on 
October 1, 2006. EPA's attainment determination is based on three 
complete years of data from 2003-2005. Therefore, the data from these 
BAM and TEOM monitors at Bakersfield Golden State Highway and Tracy 
cannot be used to determine that these sites are in attainment.
---------------------------------------------------------------------------

    \26\ While it is necessary to have three years of representative 
monitoring data to demonstrate that a monitor is attaining the 
standard, 40 CFR part 50, appendix K, section 2.3(c) states that 
there are less stringent data requirements for showing that a 
monitor has failed to attain. Since the 24-hour PM-10 standard is 
violated once a monitor averages more than one expected exceedance 
per year (averaged over three years), a monitor with four or more 
observed or expected exceedances has violated the 24-hour NAAQS even 
if there is less than three years of data (four exceedances divided 
by three years is greater than one per year).
---------------------------------------------------------------------------

    Furthermore, the BAM monitor at Tracy did not record any 
exceedances of the 24-hour PM-10 NAAQS in 2005, though an exceedance 
was recorded on September 22, 2006 (160 [mu]g/m\3\). The Bakersfield-
Golden State Highway automated equivalent monitors recorded three 
exceedances of the NAAQS during their operation, a value of 156 [mu]g/
m3 on November 22, 2005 and a value of 180 [mu]g/
m3 on November 23, 2005 (recorded on BAM monitors). Another 
exceedance (169 [mu]g/m3) was recorded by the Bakersfield-
Golden State Highway TEOM on September 22, 2006.\27\ Under 40 CFR 50.6, 
``[t]he standards are attained when the expected number of days per 
calendar year with a 24-hour average concentration above 150 [mu]g/
m3 * * * is equal or less than one.'' Therefore, because 
neither the Tracy nor the Bakersfield-Golden State Highway BAM monitor 
has averaged more than one exceedance per year, the exceedances 
recorded at these monitors do not show that the area is in violation of 
the 24-hour NAAQS. Even if the Bakersfield-Golden State Highway BAM and 
TEOM data are considered together (and even if they were quality-
assured data not subject to natural events), the exceedances recorded 
at these monitors would not show that the area is in violation of the 
standard. See Responses 18 and 19.
---------------------------------------------------------------------------

    \27\ As noted previously the District and CARB have informed EPA 
that they believe that exceedances recorded on September 22, 2006 
are due to high wind and wildfire natural events.
---------------------------------------------------------------------------

    Automated equivalent analyzers are also operated at the Fresno 1st 
site and the Corcoran site. See table on BAM and TEOM operating 
histories above. The Fresno 1st site has operated both a BAM monitor 
and a TEOM monitor for long enough that there is a three year data set 
for both analyzers. Neither the BAM nor the TEOM operated at Fresno 1st 
Street recorded any exceedances of the 24-hour NAAQS during the 2003-
2005 period, and both continue to show attainment through October 11, 
2006.
    The Corcoran site operated both a BAM monitor and a TEOM monitor 
during its history. See the table above on BAM and TEOM operating 
histories. The automated equivalent analyzers operated at the Corcoran 
site did record exceedances \28\ as summarized in the following table:
---------------------------------------------------------------------------

    \28\ An exceedance is defined as a daily value that is above the 
level of the 24-hour standard (150 [mu]g/m3) after 
rounding to the nearest 10 [mu]g/m3 (i.e. values ending 
in 5 or greater are to be rounded up. See 40 CFR part 50, appendix 
K, section 1.0.

   Corcoran Automated Equivalent Analyzer--PM-10 Exceedances 2003-2006
------------------------------------------------------------------------
                                                         Concentration
               Date  (type of analyzer)                    ([mu]g/m3)
------------------------------------------------------------------------
10/10/2003 (BAM).....................................                182
10/18/2003 (BAM).....................................                156
10/21/2003 (BAM).....................................                157
10/28/2003 (BAM).....................................                158
9/3/2004 (BAM).......................................               *217
11/21/2005 (BAM).....................................                166
11/22/2005 (BAM).....................................                177
11/23/2005 (BAM).....................................                185
11/26/2005 (BAM).....................................                166
2/27/2006 (BAM)......................................                179
9/22/2006 (TEOM).....................................              **261
------------------------------------------------------------------------
*The manual reference method monitor at Corcoran also recorded an
  exceedance of the NAAQS on this day that the State flagged as a high
  wind event under EPA's Natural Events Policy.
**As noted previously the District and CARB have informed EPA that they
  believe that exceedances recorded on September 22, 2006 are due to
  high wind and wildfire natural events.

    However, the data was not considered by EPA in its attainment 
determination because the District did not perform the flow rate checks 
of the BAM monitors as required by EPA regulations at 40 CFR part 58, 
appendix A, section 3.1.2 and CARB did not perform independent flow 
rate audits as required by 40 CFR part 58 appendix A, section 3.2.2. 
See Response to comments 7 and 13 above.\29\
---------------------------------------------------------------------------

    \29\ Under 40 CFR 58.14, because the District did not intend 
that data from these continuous monitors would be used for 
determining attainment or nonattainment, flow rate checks and audits 
were not required to be conducted. See May 8, 2006 letter to Wayne 
Nastri, Regional Administrator, EPA Region 9, from Catherine 
Witherspoon, Executive Officer, CARB with attached letter dated 
April 24, 2006 to Catherine Witherspoon, Executive Officer, CARB 
from Seyed Sadredin, Executive Director/Air Pollution Control 
Officer, San Joaquin Valley Air Pollution Control District.
---------------------------------------------------------------------------

    In determining which data to use in regulatory actions, EPA needs 
to determine whether the data meets our basic requirements. If it does 
not then we cannot use the data in regulatory decisions. During the 
three-year period of 2003-2005, the District only performed 10 of the 
78 required bi-weekly flow rate checks and CARB never performed an 
independent audit of the BAM monitor's flow rate, which is required 
annually. While the commenter implies that this is a minor

[[Page 63660]]

deficiency, EPA believes the lack of QA/QC raises significant questions 
about the reliability of the Corcoran BAM monitor data and therefore 
concluded that it would not be appropriate to rely on data from this 
monitor that did not meet our regulatory requirements.
    Comment 16: The commenter states that EPA cannot ignore the 
Corcoran BAM monitor data due to the lack of precision check of the 
flow meter. The commenter states that 40 CFR part 58, appendix A, 
section 3.1.2.2 offers an alternative procedure at section 3.1.2.2.1 
for complying with the section 3.1.2 requirement for a precision check 
of the operational flow rate of the analyzer. The alternative procedure 
involves checking the BAM monitor's internal flow meter (vs. using an 
external flow rate transfer standard) and requires an external audit of 
the flow rate at least every six months, records of the past three 
audits showing that the flow meter is stable, and no indication of 
improper operation. Section 3.1.2.2.2 even allows for the precision 
check to be carried out remotely. The commenter states that EPA has not 
analyzed whether the District properly maintained the Corcoran-
Patterson Avenue BAM monitor in accordance with section 3.1.2.2 and 
that the District's maintenance records show regular weekly 
maintenance, including checks of the on-screen flow rate, and also show 
regular external flow audits.
    Response: As stated above, there are two routine quality assurance 
checks that need to be made to monitoring instruments to ensure that 
the data they are producing is reliable. One of these is a precision 
check. The precision check for automated PM-10 analyzers, of which the 
BAM monitor is one, is addressed in 40 CFR part 58, appendix A, section 
3.1.2. See response to comment 13. This section requires a one-point 
precision check to be performed at least once every two weeks. There 
are two procedures that can be used to satisfy this requirement. The 
standard procedure is explained in section 3.1.2.1 of appendix A and 
the alternative procedure is explained in section 3.1.2.2 of appendix 
A. One of our reasons for not using data from the Corcoran BAM monitor 
is that the District did not perform the precision checks of its BAM 
monitor and submit the resulting QA data to the AQS database. The 
District performed neither the standard procedure nor the alternative 
procedure.
    The commenter implies that EPA rejected the Corcoran BAM monitor 
data even though the District had performed the sanctioned alternative 
procedure. This is not true. EPA reviewed all the maintenance records 
from the Corcoran-Patterson Avenue site and found that neither 
precision check was being performed. While the operator did check the 
BAM monitor's internal flow rate indicator routinely, the other 
requirements of 40 CFR part 58, appendix A, section 3.1.2.2 were not 
being met, i.e., the flow rate meter was not audited every six months 
and there was no documentation that the flow meter is stable, 
verifiable, and accurate to 4 percent (sections 
3.1.2.2.1.1, 3.1.2.2.1.2, 3.1.2.2.1.3). See also response to comment 13 
above. As stated in that response the precision check is one of the 
critical measurement quality checks that are needed to ensure that the 
device is performing as designed.
    Comment 17: The commenter states that EPA also cannot dismiss the 
Corcoran BAM data because CARB did not perform independent field audits 
as described in section 3.2.2 without explaining why these audits are 
important in determining the reasonableness of the data. Moreover, the 
commenter also states that EPA must demonstrate that the FRM monitors 
were appropriately audited or explain why it is reasonable for the FRM 
monitors to not be audited while excluding the BAM monitor data due to 
this oversight. EPA needs a compelling rational basis for continuing to 
exclude all of the BAM data or EPA must consider the data in 
determining the Valley's attainment status.
    Response: Regular audits of monitoring equipment are important in 
establishing the validity and accuracy of the data collected by an 
agency. Section 2.11.7.0 of EPA's QA Guidance document ``Quality 
Assurance Handbook,'' Volume II, Part II, September 1997, states that:

    [t]he primary goal of an auditing program is to identify system 
errors that may result in suspect or invalid data. The efficiency of 
the monitoring system (i.e., labor input vs. valid data output) is 
contingent upon effective quality assurance (QA) activities. This 
true assessment of the accuracy and efficiency of the PM-10 
measurement system can only be achieved by conducting an audit under 
the following guidelines:
     Without special preparation or adjustment of the system 
to be audited.
     By an individual with a thorough knowledge of the 
instrument or process being evaluated, but not by the routine 
operator.
     With accurate, calibrated NIST-traceable transfer 
standards that are completely independent of those used for routine 
calibration and QC flow checks.
     With complete documentation of audit information for 
submission to the operating agency. The audit information includes, 
but is not limited to, types of instruments and audit transfer 
standards, instrument model and serial numbers, transfer-standard 
traceability, calibration information, and collected audit data.
    The audit procedures described in this section produce two 
quantitative estimates of a PM-10 sampler's performance: The audit 
flow-rate percentage difference and the design flow-rate percentage 
difference. The audit flow-rate percentage difference determines the 
accuracy of the sampler's indicated flow rate by comparing it with a 
flow rate from the audit transfer standard. The design flow-rate 
percentage difference determines how closely the sampler's flow rate 
matches the inlet design flow rate under normal operational 
conditions.

    It is not clear to EPA why the commenter believes the FRM 
monitoring network operations do not meet EPA requirements. As 
discussed previously, the PM-10 SLAMS monitoring network meets EPA's QA 
requirements, including the requirement for independent field audits. 
See also Response to Comment 13 above.
    Comment 18: The commenter states that neither EPA nor the District 
addresses the violations recorded at the Bakersfield BAM monitor. No 
attempt is made to discredit the data coming from that BAM monitor and 
no rational basis is provided by EPA for completely disregarding those 
data.
    Response: The Bakersfield Golden State Highway BAM monitor never 
recorded any violations of the NAAQS. As explained above, the 
Bakersfield Golden State Highway automated equivalent method analyzers 
recorded three exceedances since the District began operation of these 
monitors at the site in July 28, 2005 while sampling every day. 
According to 40 CFR part 50, appendix K, this does not constitute a 
violation of the NAAQS and therefore we did not discuss it in our 
proposal. Since there are no violations at this BAM monitor, EPA did 
not need to determine whether the data was usable in making the 
attainment determination for the SJV. See response to comment 15.
    Comment 19: The commenter states that EPA does not justify ignoring 
data from the three tapered element oscillating microbalance (TEOM) 
monitors that were operated in the Valley during the 2003-2005 time 
period.
    Response: The three TEOM monitors operated during the 2003-2005 
period were located at Fresno 1st Street, Stockton Hazelton Street, and 
Corcoran Patterson Avenue. The TEOMs at Fresno and Stockton were 
operated by CARB as special purpose monitors that supplement the SLAMS 
high volume FRM samplers. The Corcoran TEOM was operated by the 
District, also as a special purpose monitor. In addition, as

[[Page 63661]]

discussed in response to comment 15 above, the District now operates 
TEOMs at its Tracy, Bakersfield-Golden State Hwy. and Corcoran 
monitoring sites.
    CARB has submitted and certified the TEOM data from the Stockton 
site to EPA's AQS database up to the date June 28, 2005, which is when 
CARB discontinued the operation of this TEOM. During the 2003 to 2005 
period, the TEOM at Stockton recorded a single exceedance of the 24-
hour NAAQS. Because of its everyday sampling schedule, this single 
exceedance at Stockton does not constitute a violation of the NAAQS. 
See response to comment 15.
    No data from any other TEOMs operating in the San Joaquin Valley 
PM-10 network has been submitted to AQS. However, EPA has obtained data 
from these TEOMs from 2003-2005 as well as a portion of 2006 and these 
data show no violations of the PM-10 NAAQS have been recorded for this 
period.
    As discussed above in response to comment 15 EPA is aware of TEOMs 
currently operating at four monitoring sites in the San Joaquin PM-10 
network: Bakersfield-Golden State Highway, Corcoran, Fresno 1st Street 
and Tracy. Two of these TEOMs, Fresno and Tracy,\30\ recorded no 
exceedances of the NAAQS. Two other TEOMS, Bakersfield and Corcoran, 
recorded exceedances on September 22, 2006, which, as noted above, is a 
date associated with a high wind and fire event. This is the only 
exceedance day we are aware of for these TEOMS. All data EPA has 
received from the District and CARB collected by BAMs and TEOMs have 
been included in the Docket. Thus, in sum these TEOM monitors would not 
show that the area is in violation of the standard.
---------------------------------------------------------------------------

    \30\ The Tracy TEOM began monitoring on October 1, 2006.
---------------------------------------------------------------------------

    Comment 20: The commenter states that EPA must also consider all 
publicly available data, including ``data available from other sources 
including those special purpose monitors operated by third parties'' 
(1997 Seitz memo) and that EPA has not made any assertion regarding 
data from third party monitors. If such data exists, EPA must consider 
it or must explain why it is reasonable to exclude this information.
    Response: The commenter has not provided any data from any so-
called ``third party monitors.'' Nor is EPA aware of any data available 
from third parties that meets our regulatory requirements and could be 
used in this action.
    Comment 21: The commenter maintains that ``[t]hese continuous 
monitors demonstrate an ongoing PM-10 problem in the Valley'' and that 
monitoring professionals within EPA and CARB know that these monitors 
provide the most accurate, realistic picture of Valley air quality. 
These monitors are used for detailed air quality studies, public health 
alerts, and modeling in the State implementation plan. In fact, CARB 
performed a comparison study of BAM technology versus FRM technology 
and found that, far from the dramatic picture the District paints of 
wildly inaccurate monitor readings, BAM monitors enjoy ``good 
precision'' and may actually capture certain semi-volatile pollutants 
that FRM monitors do not.
    Response: The CARB study cited by the commenter is one that 
compared PM-2.5 BAM and PM-2.5 FRM performance. PM-2.5 is a different 
pollutant from PM-10 even though both are based on particulates, but 
the type of particles that make up PM-10 versus PM-2.5 can be very 
different. The issue for EPA is not what type of equipment was used by 
the State or District to collect PM-10 data, but whether the data and 
the monitors used to collect it met EPA's quality assurance 
requirements.
    The BAM monitor is a designated Federal equivalent method for PM-
10. If the District had performed the appropriate QA procedures, as 
discussed elsewhere in this action, EPA would have considered the BAM 
data when making our attainment finding.
    Comment 22: If EPA now wants to ignore and dismiss this data, EPA 
needs to provide a reasonable explanation, not hide behind 
technicalities it picks and chooses in order to support its political 
agenda. EPA's proposal provides none of the necessary technical 
analysis needed to give this reasonable basis. As a result, commenters 
are unable to provide meaningful comment on that basis. EPA must 
prepare a supplemental notice of proposed rulemaking to provide the 
missing analysis.
    Response: EPA did provide a reasonable explanation for not using 
the BAM data in its decision to find that the SJV has attained the PM-
10 NAAQS. As set forth in the proposal to this action, the BAM data did 
not meet our QA/QC requirements. The SLAMS data from the FRM network 
met our requirements. Thus EPA believes it does not need to prepare a 
supplemental notice of proposed rulemaking because the substance of its 
analysis was adequately included in its proposal.

G. Representativeness of Data

    Comment 23: The commenter states that ``EPA should determine 
whether conditions of [the] last three years are typical'' or ``whether 
conditions during this period are representative of normal conditions 
for the Valley.'' The commenter points to a 1997 progress report and 
statements made by the District recommending caution regarding any 
improvements in monitored PM-10 levels in the SJV. The commenter also 
cites a Pittsburgh-Beaver Valley, Pennsylvania area rule (61 FR 28061, 
28063) in which EPA revoked an attainment determination and pointed to 
the varied number of exceedances over the preceding years and the 
failure of the area to adequately reduce emissions as grounds for not 
dismissing new data indicating a continued pollution problem. Finally, 
the commenter notes that the District recently argued to EPA and the 
Ninth Circuit Court of Appeals that there was absolutely no way the SJV 
could attain the PM-10 standard by 2006, further emphasizing the need 
to evaluate whether the conditions of the last few years are an 
anomaly.
    Response: The requirement to determine that clean air is the result 
of permanent and enforceable emissions reductions is a criterion for 
the redesignation of an area to attainment under CAA section 
107(d)(3)(E).\31\ This criterion need not be met for a determination of 
attainment or for the suspension of the associated RFP, attainment 
demonstration, and/or contingency measure requirements.
---------------------------------------------------------------------------

    \31\ The redesignation of an area to attainment under CAA 
section 107(d)(3)(E) is a separate process from a finding of 
attainment. Unlike an attainment finding where we need only 
determine that the area has had the prerequisite number of clean 
years, a redesignation requires multiple determinations. Under 
section 107(d)(3)(E) these determinations are: (1) We must 
determine, at the time of the redesignation, that the area has 
attained the relevant NAAQS; (2) The state must have a fully 
approved SIP for the area; (3) We must determine that the 
improvements in air quality are due to permanent and enforceable 
reductions in emissions resulting from implementation of the SIP and 
applicable federal regulations and other permanent and enforceable 
reductions; (4) We must have fully approved a maintenance plan for 
the area under section 175A; (5) The state must have met all the 
nonattainment area requirements applicable to the area.
---------------------------------------------------------------------------

    That aside, we believe that the attainment determination itself 
addresses in part the concern about unusually favorable meteorological 
conditions. We have long recognized that yearly variations in 
meteorological conditions can have a profound effect on ambient PM-10 
concentrations. In setting the PM-10 standards in 1987, we changed the 
form of the 24-hour and annual standards to a statistical form which is 
based on exceedances and annual averages over 3 consecutive years. EPA 
stated that ``[t]he problem of

[[Page 63662]]

year-to-year variability is * * * reduced by averaging three years of 
data.'' See proposed and final actions promulgating the PM-10 standards 
at 49 FR 10408, 10413 (March 20, 1984) and 52 FR 24635, 24639-24641 
(July 1, 1987).
    In the case of the Pittsburgh-Beaver Valley, Pennsylvania area rule 
(61 FR 28061, 28063), EPA revoked an attainment determination due to 
violations of the ozone NAAQS that occurred after the determination was 
made. In response to a comment suggesting that EPA should ignore the 
violations due to year-to-year variability, EPA stated that ``[b]ecause 
the area has not adequately reduced its VOC and NOX 
emissions, it is subject to ozone exceedances whenever meteorological 
conditions are conducive to ozone formation.'' The commenter on our 
proposed attainment determination for the SJV implies that because EPA 
recognizes year-to-year variability in data and that both the SJV and 
the Pittsburgh-Beaver Valley areas had variable data over the years, 
EPA should address whether conditions were typical or normal before 
making the attainment determination for SJV. However, the SJV has 3 
recent years (2003-2005) of clean data whereas the Pittsburgh-Beaver 
Valley area did not have clean data at the time of the attainment 
determination revocation.
    The 2003 PM-10 Plan demonstrates attainment of the PM-10 standards 
by 2010. 69 FR 30006. The 2003 PM-10 Plan's attainment demonstration is 
based on air quality modeling of emissions reductions from State and 
District measures. As such it is a prediction of what ambient 
conditions will be in the future. In contrast, as discussed above, a 
determination of attainment, based on monitored air quality data, 
reflects actual ambient conditions over a three year period. Given the 
margin of error in air quality modeling, particularly for PM-10, a 
disparity between modeling and monitored data is not unusual. While, as 
stated above, the three year requirement does to a certain extent 
address anomalous meteorological conditions, an analysis of whether ``* 
* * the improvements in air quality are due to permanent and 
enforceable reductions in emissions * * *'' is primarily addressed as a 
prerequisite for redesignation of an area to attainment under CAA 
section 107(d)(3)(E) to ensure that reductions will remain in place 
even where weather variations occur.
    Finally, the commenter also points to statements made in a SJV 1997 
PM-10 progress report in which the District discusses the favorable 
meteorological conditions (i.e., rain) during 1993-1998 which may or 
may not have led to fewer PM-10 exceedances. However, our PM-10 
attainment determination is based on the years 2003-2005. Again, 
whether or not 2003-2005 was a period of normal conditions and whether 
the SJV could continue to demonstrate attainment under all predicted 
weather conditions is a criterion that must be addressed in connection 
with a redesignation, but not for an attainment determination.
    Comment 24: The commenter contends that EPA's decision is not 
reasonable, and that EPA has never attempted to make an attainment 
determination based on so few years of monitoring and in the face of 
such countervailing evidence. The commenter further contends that EPA 
is motivated by a desire to avoid legal deadlines.
    Response: As set forth above, in responses to comments, EPA 
believes that its decision is a reasonable one, based on three complete 
years of quality-assured data, and supported by the evidence. Moreover, 
the commenter is wrong in alleging that EPA has never before based a 
determination of attainment on three years of data. EPA has in numerous 
instances done so. See, for example, 60 FR 37366 (July 20, 1995) (Grand 
Rapids), 66 FR 1925 (January 10, 2001) and 66 FR 53094 (October 19, 
2001) (Pittsburgh-Beaver Valley), 66 FR 27583 (May 17, 2001) and 66 FR 
53655 (October 23, 2001) (Louisville), 68 FR 25418, 25429 (May 12, 
2003) (St. Louis), 69 FR 21717 (April 22, 2004) (Bay Area). The 
commenter's speculation as to EPA's motivation is irrelevant. EPA's 
determination that the SJV area has attained the standards is, as shown 
elsewhere in this notice, supported by quality assured data and in 
compliance with statutory and regulatory requirements.

H. Other Comments

    Comment 25: Approximately two thousand commenters sent letters (all 
via e-mail except one via postcard) to EPA stating that they are 
concerned about the attainment determination. All commenters were 
specifically concerned about the air quality in the Valley, about a 
monitoring network that reads only once every six days and does not 
account for the agriculture-heavy west side and about EPA ignoring 
violations from monitors. Commenters were also concerned that the 
finding would relieve EPA and the District of obligations to continue 
to address the particulate matter problem and air pollution problems in 
general. Many commenters provided personal accounts of health issues 
(e.g., asthma, difficulty breathing, hospital visits, use of inhalers) 
while living in the San Joaquin Valley.
    Response: As noted above, the comments of individual citizens 
raised many of the same issues set forth in the comments of 
Earthjustice, and EPA has addressed those comments in the context of 
its responses to Earthjustice. Like the commenters, EPA is concerned 
about the air quality of the SJV and the health of its residents. The 
SJV is a nonattainment area for ozone as well as for PM-10 and PM-2.5. 
In general in the SJV, ozone is a summertime problem and PM is a fall 
and wintertime problem. EPA has invested significant resources in 
developing clean air plans and measures to reduce the air pollution in 
the SJV to levels considered safe by Federal standards. EPA's 
determination that the SJV has attained the PM-10 standards does not in 
any way relieve the District, State, or EPA of any of the strategies 
currently in place to achieve cleaner air.\32\ CARB and the District 
have stated this in their request for an attainment determination (May 
8, 2006 letter to Wayne Nastri, Regional Administrator, EPA Region 9, 
from Catherine Witherspoon, Executive Officer, CARB) and the District 
has restated it in its comment letter in connection with this 
rulemaking (August 14, 2006 letter to Doris Lo, EPA Region 9, from 
Seyed Sadredin, Executive Director/Air Pollution Control Officer, San 
Joaquin Valley Unified Air Pollution Control District). The measures 
and commitments approved by EPA in the 2003 PM-10 Plan continue to be 
implemented, and EPA expects more strategies and measures that will 
lead to further reductions as the District and CARB develop plans to 
meet the more stringent PM-2.5 NAAQS and the 8-hour ozone standard.
---------------------------------------------------------------------------

    \32\ In addition, CARB or the District cannot revise their SIP 
to drop any SIP-approved strategies unless they can demonstrate that 
the revision will not ``* * * interfere with any applicable 
requirement concerning attainment and reasonable further progress * 
* * or any other applicable requirement * * *'' of the Act. See 
section 110(l) of the CAA.
---------------------------------------------------------------------------

    Furthermore, while some monitors may only take ambient air quality 
readings once every six days, the data from these monitors is adjusted 
to account for the days that are not monitored. Thus, as a simplified 
example, if a one in six day monitor records an exceedance of the PM-10 
NAAQS, that exceedance must be multiplied by six to account for the 
days it did not monitor. In addition, EPA disagrees with the 
commenter's assertion that the agricultural sources of the western side 
of the Valley are not accounted for. The Corcoran monitoring

[[Page 63663]]

site does monitor emissions from agricultural sources and is thus 
representative of air quality levels in the western portion of the 
Valley. In addition, the agricultural regulations for the SJV are 
applicable to sources throughout the Valley, including those in the 
western portion of the SJV. Finally, EPA does not ignore actual 
violations, but as discussed in response to comments above, certain 
data purporting to show exceedances of the PM-10 standard may be 
excluded in determining whether an actual violation has occurred for 
various reasons, including the need to assure that data are reliable 
and accurate.
    Comment 26: One commenter sent pictures of dust from combines on an 
agricultural field and stated that incentives were needed to help keep 
the dust on the ground. The commenter also discussed dusty conditions 
during the almond and cotton harvest in November 2005 throughout the 
SJV. The commenter is a farmer and believes that farmers are doing a 
good job of keeping dust (laden with pesticides and other residues) on 
the ground during the growing season because it benefits the farmer, 
but that there are no incentives for controlling the dust from roads. 
Finally, the commenter is concerned that even with the new NAAQS in the 
future, the attainment determination will lead to relaxation of 
enforcement and monitoring when more progressive and innovative steps 
are needed.
    Response: The SJV has requirements that control dust from 
agricultural sources such as those discussed by the commenter. See 
District Rules 4550 and 8081. These requirements cover almond, cotton 
and other types of farming operations in the SJV and include measures 
that reduce dust from roads. The new more stringent PM-2.5 standards 
will lead to additional measures; however, even without these new 
standards, because the 24-hour PM-10 standard remains in effect, the 
enforcement of measures to reduce PM-10 and monitoring of PM-10 will 
still be required (see also above response to comment 14).

III. Final Action

    Based on 2003-2005 quality-assured data meeting the requirements of 
40 CFR part 50, appendix K, as well as data showing continued 
attainment, EPA is finalizing its determination that the SJV has 
attained the 24-hour and annual PM-10 NAAQS. The SJV continues to 
attain the PM-10 NAAQS in 2006 based on all available quality assured 
data. This action does not constitute a redesignation to attainment 
under CAA section 107(d)(3), because we do not yet have an approved 
maintenance plan as required under section 175(A) of the CAA or a 
determination that the area has met the other CAA requirements for 
redesignation. The classification and designation status in 40 CFR part 
81 remains serious nonattainment for this area until such time as 
California meets the CAA requirements for redesignation of the SJV to 
attainment.
    Consistent with the Agency's Clean Data Policy and its 
interpretation that the attainment determination suspends certain 
requirements as set forth in detail above, EPA is also finalizing its 
finding that the contingency measure requirements of CAA section 
172(c)(9) no longer apply to the San Joaquin Valley PM-10 nonattainment 
area for so long as the area continues to attain the PM-10 NAAQS. If we 
subsequently determine, after notice and comment rulemaking in the 
Federal Register, that the area has violated the standard (prior to a 
redesignation to attainment), the requirement for contingency measures 
would once again be applicable.

IV. Effective Date of This Final Action

    The EPA finds that there is good cause for this action to become 
effective immediately upon publication because a delayed effective date 
is unnecessary due to the nature of this action, which is a 
determination, based on air quality data, that certain Act requirements 
do not apply for so long as the area continues to attain the standard. 
The immediate effective date for this action is authorized under both 5 
U.S.C. 553(d)(1) which provides that rulemaking actions may become 
effective less than 30 days after publication if the rule ``grants or 
recognizes an exemption or relieves a restriction'' and 5 U.S.C. 
553(d)(3), which allows an effective date less than 30 days after 
publication ``as otherwise provided by the agency for good cause found 
and published with the rule.''

V. Statutory and Executive Order Reviews

    Under Executive Order 12866 (58 FR 51735, October 4, 1993), this 
action is not a ``significant regulatory action'' and therefore is not 
subject to review by the Office of Management and Budget. For this 
reason, this action is also not subject to Executive Order 13211, 
``Actions Concerning Regulations That Significantly Affect Energy 
Supply, Distribution, or Use'' (66 FR 28355, May 22, 2001). This action 
merely makes a determination based on air quality data, suspends 
certain requirements, and imposes no additional requirements. 
Accordingly, the Administrator certifies that this rule will not have a 
significant economic impact on a substantial number of small entities 
under the Regulatory Flexibility Act (5 U.S.C. 601 et seq.). Because 
this rule does not impose any additional enforceable duty, it does not 
contain any unfunded mandate or significantly or uniquely affect small 
governments, as described in the Unfunded Mandates Reform Act of 1995 
(Pub. L. 104-4).
    This rule also does not have tribal implications because it will 
not have a substantial direct effect on one or more Indian tribes, on 
the relationship between the Federal Government and Indian tribes, or 
on the distribution of power and responsibilities between the Federal 
Government and Indian tribes, as specified by Executive Order 13175 (65 
FR 67249, November 9, 2000). This action also does not have Federalism 
implications because it does not have substantial direct effects on the 
States, on the relationship between the national government and the 
States, or on the distribution of power and responsibilities among the 
various levels of government, as specified in Executive Order 13132 (64 
FR 43255, August 10, 1999). This action merely makes a determination 
based on air quality data and suspends certain requirements, and does 
not alter the relationship or the distribution of power and 
responsibilities established in the Clean Air Act. This rule also is 
not subject to Executive Order 13045 ``Protection of Children from 
Environmental Health Risks and Safety Risks'' (62 FR 19885, April 23, 
1997), because it is not economically significant.
    The requirements of section 12(d) of the National Technology 
Transfer and Advancement Act of 1995 (15 U.S.C. 272 note) do not apply 
because it would be inconsistent with applicable law for EPA, when 
determining the attainment status of an area, to use voluntary 
consensus standards in place of promulgated air quality standards and 
monitoring procedures that otherwise satisfy the provisions of the 
Clean Air Act. This rule does not impose an information collection 
burden under the provisions of the Paperwork Reduction Act of 1995 (44 
U.S.C. 3501 et seq.).
    The Congressional Review Act, 5 U.S.C. 801 et seq., as added by the 
Small Business Regulatory Enforcement Fairness Act of 1996, generally 
provides that before a rule may take effect, the agency promulgating 
the rule must submit a rule report, which includes a copy of the rule, 
to each House of the Congress and to the Comptroller General of the 
United States. EPA will submit a report containing this rule and other 
required information to the U.S. Senate,

[[Page 63664]]

the U.S. House of Representatives, and the Comptroller General of the 
United States prior to publication of the rule in the Federal Register. 
A major rule cannot take effect until 60 days after it is published in 
the Federal Register. This action is not a ``major rule'' as defined by 
5 U.S.C. 804(2).
    Under section 307(b)(1) of the Clean Air Act, petitions for 
judicial review of this action must be filed in the United States Court 
of Appeals for the appropriate circuit by December 29, 2006. Filing a 
petition for reconsideration by the Administrator of this final rule 
does not affect the finality of this rule for the purposes of judicial 
review nor does it extend the time within which a petition for judicial 
review may be filed, and shall not postpone the effectiveness of such 
rule or action. This action may not be challenged later in proceedings 
to enforce its requirements. (See section 307(b)(2).)

List of Subjects

40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Particulate matter, Reporting and recordkeeping 
requirements.

40 CFR Part 81

    Environmental protection, Air pollution control, National parks, 
Wilderness areas.

    Dated: October 17, 2006.
Laura Yoshii,
Acting Regional Administrator, Region 9.
[FR Doc. 06-8902 Filed 10-27-06; 8:45 am]

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