Document ID: EPA-R08-OAR-2007-1035-0007
Agency: epa
Document Type: Rule
Title: Federal Register Action. Final Rule. Colorado; Interstate Transport of Pollution SIP Revisions for the 1997 8-hour Ozone NAAQS. Interference with Maintenance Requirement.
Posted Date: 2010-11-22T05:00Z

[Federal Register Volume 75, Number 224 (Monday, November 22, 2010)]
[Rules and Regulations]
[Pages 71029-71033]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-29245]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R08-OAR-2007-1035; FRL-9229-2]

Approval and Promulgation of State Implementation Plans; State of 
Colorado; Interstate Transport of Pollution Revisions for the 1997 8-
Hour Ozone NAAQS: ``Interference With Maintenance'' Requirement

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is partially approving State Implementation Plan (SIP) 
revisions submitted by the State of Colorado on June 18, 2009. 
Specifically, EPA is approving the portions of the ``State of Colorado 
Implementation Plan to Meet the Requirements of Clean Air Act (CAA) 
Section 110(a)(2)(D)(i)(I)--Interstate Transport Regarding the 1997 8-
Hour Ozone Standard'' addressing the ``interference with maintenance'' 
requirement of section 110(a)(2)(D)(i)(I) for the 1997 8-hour ozone 
National Ambient Air Quality Standards (NAAQS) by any other state. The 
``interference with maintenance'' requirement of section 
110(a)(2)(D)(i)(I) prohibits a state's emissions from interfering with 
maintenance of the NAAQS by any other state. This action is being taken 
under section 110 of the CAA.

DATES: Effective Date: This final rule is effective December 22, 2010.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. EPA-R08-OAR-2007-1035. All documents in the docket are listed on 
the http://www.regulations.gov Web site. Although listed in the index, 
some information is not publicly available, e.g., Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. Certain other material, such as copyrighted material, is 
not placed on the Internet and will be publicly available only in hard 
copy form. Publicly available docket materials are available either 
electronically through http://www.regulations.gov, or in hard copy at 
the Air Program, Environmental Protection Agency (EPA), Region 8, 1595 
Wynkoop Street, Denver, Colorado 80202-1129. EPA requests that if at 
all possible, you contact the individual listed in the FOR FURTHER 
INFORMATION CONTACT section to view the hard copy of the docket. You 
may view the hard copy of the docket Monday through Friday, 8 a.m. to 4 
p.m., excluding Federal holidays.

FOR FURTHER INFORMATION CONTACT: Domenico Mastrangelo, Air Program, 
U.S. Environmental Protection Agency, Region 8, Mailcode 8P-AR, 1595 
Wynkoop Street, Denver, Colorado 80202-1129, (303) 312-6416, 
mastrangelo.domenico@epa.gov.

SUPPLEMENTARY INFORMATION: 

Definitions

    For the purpose of this document, we are giving meaning to certain 
words or initials as follows:
    (i) The words or initials Act or CAA mean or refer to the Clean Air 
Act, unless the context indicates otherwise.
    (ii) The words EPA, we, us or our mean or refer to the United 
States Environmental Protection Agency.
    (iii) The initials SIP mean or refer to State Implementation Plan.
    (iv) The words Colorado and State mean the State of Colorado.

Table of Contents

I . Background
II. Response to Comments
III. Final Action
IV. Statutory and Executive Order Review

I. Background

    On July 18, 1997, EPA promulgated new standards for 8-hour ozone 
and fine particulate matter (PM2.5). This action is being 
taken in response to the July 18, 1997 revision to the 8-hour ozone 
NAAQS. This action does not address the requirements for the 1997 
PM2.5 NAAQS, the 2006 PM2.5 NAAQS, or the 2008 8-
hour ozone NAAQS; those standards will be addressed in a later action.
    Section 110(a)(1) of the CAA requires states to submit SIPs to 
address a new or revised NAAQS within 3 years after promulgation of 
such standards, or within such shorter period as EPA may prescribe. 
Section 110(a)(2) lists the elements that such new SIPs must address, 
as applicable, including section 110(a)(2)(D)(i) which pertains to 
interstate transport of certain emissions. Section 110(a)(2)(D)(i) of 
the CAA requires that a state's SIP must contain adequate provisions 
prohibiting any source or other type of emissions activity within the 
state from emitting any air pollutant in amounts which will: (1) 
Contribute significantly to nonattainment of the NAAQS in any other 
state; (2) interfere with maintenance of the NAAQS by any other state; 
(3) interfere with any other state's required measures to prevent 
significant deterioration of air quality; or (4) interfere with any 
other state's required measures to protect visibility.
    On June 18, 2009 the State of Colorado submitted a SIP addressing 
the section 110(a)(2)(D)(i)(I) requirements (1) and (2), noted above, 
for the 1997 8-hour ozone NAAQS. The state based its submittal on EPA's 
2006 Guidance discussed below. As noted earlier, in this rulemaking EPA 
is addressing the requirement that pertains to preventing sources in 
the State from emitting pollutants in amounts which will interfere with 
the maintenance of the 1997 8-hour ozone NAAQS by any other state.
    On August 15, 2006, EPA issued its ``Guidance for State 
Implementation Plan (SIP) Submission to Meet Current Outstanding 
Obligations Under Section 110(a)(2)(D)(i) for the 8-Hour Ozone and 
PM2.5 National Ambient Air Quality Standards'' (2006 
Guidance) for SIP submissions that states should use to

[[Page 71030]]

address the requirements of section 110(a)(2)(D)(i). EPA developed this 
guidance to make recommendations to states for making submissions to 
meet the requirements of section 110(a)(2)(D)(i) for the 1997 8-hour 
ozone NAAQS and 1997 PM2.5 NAAQS.
    In a Federal Register action dated September 17, 2010, EPA proposed 
approval of the Colorado Interstate Transport SIP portions addressing 
the interference with maintenance requirement of section 
110(a)(2)(D)(i)(I). EPA concluded in its proposed action that the 
various factual and technical considerations supported a determination 
that emissions from Colorado do not interfere with maintenance by any 
states with areas at risk for maintenance of the 1997 8-hour ozone 
NAAQS. EPA did not receive comments that persuade the Agency that there 
is such interference, and thus in today's final action EPA is making a 
final regulatory determination that Colorado emissions sources do not 
interfere with maintenance of the 1997 8-hour ozone NAAQS in any other 
state.

II. Response to Comments

    EPA received one letter dated October 18, 2010 with comments from 
the WildEarth Guardians (WG) environmental organization. The WG letter 
includes three separate comments under sections A., B., and C., and is 
accessible online at regulations.gov under Docket No. EPA-R08-OAR-2007-
1035. Later in this section EPA responds to the significant comments 
made by the commenter. WG clarifies in its introductory remarks on the 
letter's first page that its comments are directed to both the Colorado 
and the North Dakota Federal Register proposed rule actions of 
September 17, 2010 (75 FR 56935 and 75 FR 56928) because ``EPA's 
rationale for approving both SIPs is the same.'' EPA will consider WG's 
comments, as appropriate, equally applicable to the referenced EPA 
proposed rule actions. For clarity, however, in this action EPA will 
address WG's comments as if they were directed only to the proposed 
rule action for Colorado (75 FR 56935).\1\
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    \1\ Similarly, in our response to the same WG comments in our 
action finalizing the proposed rule action of September 17, 2010 for 
the North Dakota ``interference with maintenance'' requirement, we 
address WG's comments as if they were directed to the proposed rule 
action for North Dakota (75 FR 56928).
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    Comment No. 1--In its comments under section A., ``Maintenance is 
Inappropriately Defined,'' WG states that EPA's definition of 
interference with maintenance, and by implication the identification of 
maintenance receptors, appeared to be ``inappropriately conflated with 
the definition of nonattainment.'' It argues that the definition of 
maintenance appeared to be tied to nonattainment, asserting that 
``unless an area has violated or is in violation of the NAAQS, the 
agency will not consider whether * * * Colorado [is] interfering with 
that area's ability to maintain compliance with the NAAQS.'' For this 
reason, WG argues EPA did not give independent meaning to the interfere 
with maintenance prong of section 110(a)(2)(D)(i)(I).
    EPA Response--The methodology EPA used to identify maintenance 
receptors gives independent meaning to the term ``interfere with 
maintenance'' and establishes a process to identify projected 
attainment receptors that, based on the historic variability of air 
quality at that site (which may be due to variability in emissions and/
or meteorology), may have difficulty maintaining the standard. As 
explained in greater detail below, the commenter's objection to EPA's 
approach appears to be based on the misconception that the methodology 
EPA used to identify maintenance sites was dependent on base year NAAQS 
violations.
    The definition of maintenance used by EPA is consistent with the 
direction given to EPA by the Court of Appeals for the D.C. Circuit in 
North Carolina v. EPA, 531 F.3d 896 (D.C. Cir. 2008).\2\ In that case, 
the court analyzed the definition of ``interfere with maintenance'' 
used in the Clean Air Interstate Rule (CAIR) rule. The court found that 
the definition EPA used ``gave no independent significance to the 
`interfere with maintenance' prong of section 110(a)(2)(D)(i)(I) to 
separately identify upwind sources interfering with downwind 
maintenance.'' \3\ It further reasoned that ``[u]nder EPA's reading of 
the statute, a state can never `interfere with maintenance' unless EPA 
determines that at one point it `contribute[d] significantly to 
nonattainment'.'' \4\ Based on this analysis, the court found the 
definition unlawful, holding that ``[b]ecause EPA describes CAIR as a 
complete remedy to a section 110(a)(2)(D)(i)(I) violation and does not 
give independent significance to the `interfere with maintenance' 
language to identify upwind states that interfere with downwind 
maintenance, it unlawfully nullifies that aspect of the statute and 
provides no protection for downwind areas that, despite EPA's 
predictions, still find themselves struggling to meet NAAQS due to 
upwind interference in 2010.'' \5\
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    \2\ As EPA noted in the proposal, the term ``interfere with 
maintenance'' is not defined in the CAA. As such, the term is 
ambiguous and EPA's interpretation of that term in this action is 
both reasonable and consistent with the text and the overall goals 
of the CAA. By this approach, EPA is giving independent meaning to 
the term and supporting that interpretation with technical analysis 
to apply it to the facts in this action.
    \3\ 531 F.3d at 910.
    \4\ Id.
    \5\ Id. at 910-11.
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    The approach used by EPA in its September 17, 2010 proposal to 
assess whether emissions from sources in Colorado interfere with 
maintenance of the NAAQS in any other state takes into account the 
flaws identified by the court, by giving independent meaning to the 
section 110(a)(2)(D)(i) ``interference with maintenance'' requirement. 
Our September 17, 2010 proposed action relies on a process established 
by EPA's August 2, 2010 Transport Rule Proposal to identify any 
specific receptors in downwind states that, even though they are 
projected to be in attainment and thus would not be nonattainment 
receptors, may have difficulty maintaining the NAAQS in question. These 
receptors are referred to as maintenance receptors.
    The commenter's statement that EPA's designation of maintenance 
receptors is ``firmly hitched to a finding that the maximum design 
value based on a single three-year period between 2003 and 2007 is in 
excess of the NAAQS'' appears to be based on a misunderstanding of the 
methodology used by EPA to identify maintenance receptors. EPA's 
methodology did not, as the commenter appears to assume, require a site 
to have a design value above the NAAQS for one of the three base 
periods (2003-2005, 2004-2006, 2005-2007) to be considered a 
maintenance site. The methodology is based on an analysis of the future 
year average and future year maximum design values.\6\ It does not 
depend on the whether the base year design values exceed the NAAQS. The 
Transport Rule Proposal explained that EPA used the average 
concentrations of the three design values for the three base periods 
noted above to determine the 2012 average design value at monitoring 
sites. Monitoring sites with projected average design values above the 
NAAQS would be in nonattainment, while those with projected average 
design values below the NAAQS would be in attainment in 2012. To 
identify among the attainment monitoring sites those at risk for 
maintenance of the NAAQS, EPA also projected to 2012 each of the three 
design values for the base periods noted

[[Page 71031]]

above. If the maximum of the three was above the NAAQS, then monitoring 
site was identified as at risk for maintenance of the NAAQS, or as a 
``maintenance receptor.'' \7\ The maximum design value referenced in 
this sentence is the maximum future design value calculated using each 
of the three base design value periods separately. Whether or not one 
of the three base period design values exceeded the NAAQS was not a 
factor considered in determining whether a site was a maintenance 
receptor.
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    \6\ The process that defines the monitors at risk for 
maintenance was summarized in the September 17, 2010 proposed rule 
action for the Colorado Interstate Transport SIP (75 FR 56938).
    \7\ 75 FR 45210, at 45246.
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    To better understand this concept, it is useful to compare the 
methodologies used in the Transport Rule proposal (75 FR 5210, Aug. 2, 
2010) to identify nonattainment and maintenance receptors. In the 
Transport Rule proposal, base period (2003-2007) ambient data were 
projected to the future (using model outputs) to identify both 
nonattainment and maintenance receptors. In both cases, receptors were 
identified by projected future design values; however, because more 
conservative data were used for the maintenance analysis, this analysis 
could identify receptors that were projected by the nonattainment 
analysis to be in attainment; yet might have difficulty attaining the 
standard due to historic variability of air quality at that site. To 
identify future nonattainment sites we calculated the future year 
design values by projecting the 5-year weighted average design value 
for each site. Only if this future year design value exceeded the NAAQS 
was the site considered to be a nonattainment receptor. However, to 
identify projected maintenance sites we used a different methodology 
that took into account historic variability in air quality at each 
receptor. For this approach we calculated the maximum future year 
design value by processing each of the three base design value periods 
(2003-2005, 2004-2006, and 2005-2007) separately. The highest of the 
three future values is the maximum design value, which is used to 
determine maintenance receptors.
    In this way, EPA's analysis identifies those areas that are 
projected to be attainment, but may have difficulty maintaining 
attainment of the standard, for example in a year with particularly 
severe meteorology (weather that is conducive to ozone and/or 
particulate formation). In other words, this analysis does exactly what 
the DC Circuit directed EPA to do in North Carolina. It gives 
independent meaning to the ``interfere with maintenance'' prong of 
110(a)(2)(D)(i) and provides protection to any areas that, although 
they are predicted to attain the standard (and thus upwind sources 
could not be found to significantly contribute to nonattainment in that 
area) may have difficulty maintaining the standard.\8\
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    \8\ Id. at 45246.
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    EPA used this same approach to identify any potential maintenance 
receptors for purposes of evaluating Colorado's SIP submission. For the 
reasons explained above, this approach is both reasonable and 
consistent with the direction given to EPA by the DC Circuit in North 
Carolina.
    Comment No. 2--In its comments under section B., ``Even Under EPA's 
Definition of Maintenance, Maintenance Receptors are not Consistently 
Defined,'' WG argues that EPA's approach to evaluating interference 
with maintenance is inappropriate because it did not take into account 
current high ambient concentrations in certain places. The commenter 
thus contends that EPA's identification of maintenance receptors is 
inconsistently applied. The commenter identifies several areas that it 
believes should have been considered as at risk for maintenance for the 
1997 8-hour ozone NAAQS. WG specifies the Wasatch Front and Uintah 
County in Utah, the Phoenix area in Arizona, portions of western 
Wyoming, and San Juan County in New Mexico, as areas appropriate for an 
assessment of whether emissions from Colorado interfere with their 
difficulty (in the commenter's view) in maintaining the 1997 8-hour 
ozone NAAQS.\9\
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    \9\ This comment also argues about the Denver Metropolitan Area/
North Front Range (DMA/NFR) area as at risk for maintenance for the 
1997 8-hour ozone NAAQS. We are examining this part of the comment 
within EPA's final rulemaking action for the North Dakota Interstate 
Transport SIP, since the issue of the DMA/NFR area as at risk for 
maintenance does not affect our September 17, 2010 proposed rule 
assessment of whether Colorado's emissions interfere with 
maintenance of the NAAQS by any other states.
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    EPA Response--EPA shares the commenter's concern about areas 
presently affected by elevated ozone concentrations, but disagrees with 
the commenter's assertion that the September 17, 2010, proposed rule 
action for the Colorado SIP ``overlooked areas impacted by Colorado 
that are projected to barely attain the 1997 ozone NAAQS.'' First, the 
underlying issue raised in this comment is substantively the same as 
that raised in comment no. 3 below, which argues that EPA's analysis is 
faulty because it identifies receptors likely to have difficulty 
maintaining the standard in 2012 and not at the present time. EPA's 
response to comment no. 3 below illustrates how its approach, based on 
modeling analyses that identify receptors at risk for maintenance in 
the year 2012, is appropriate and consistent with the D.C. Circuit 
decision in North Carolina v. EPA.
    Second, EPA has developed in the Transport Rule Proposal of August 
2, 2010 an approach that necessarily requires years of data, and an 
analysis that evaluates where there may be difficulties with 
maintaining attainment at a specific point in time (in this instance 
2012) to evaluate whether there is interference with maintenance to 
meet the statutory requirement of section 110(a)(2)(D)(i).\10\ To 
assist in the evaluation of whether states' emissions interfere with 
maintenance of the NAAQS in western states, EPA has developed, 
independent of the Transport Rule Proposal, a modeling analysis using 
an approach similar to the Transport Rule Proposal for the 
identification of monitors at risk for maintenance of the NAAQS within 
a modeling domain that includes the western states. The analysis is 
presented in the August 23, 2010 memo, ``Documentation of Future Year 
Ozone and Annual PM2.5 Design Values for Western States'' 
(Western States Design Values).\11\ Because none of the areas of 
concern to the commenter was identified by EPA as a maintenance 
receptor through that analysis,\12\ it was appropriate for the 
September 17, 2010 proposed rule not to assess whether emissions from 
Colorado sources impact the areas noted by the commenter, such as 
Uintah County and Wasatch Front in Utah, the Phoenix area in Arizona, 
portions of western Wyoming, and San Juan County in New Mexico. In 
short, based on EPA's analysis, none of the areas named by the 
commenter is appropriate for consideration as a maintenance receptor at 
this time.
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    \10\ 75 FR 45210.
    \11\ A memorandum in the docket for this action provides the 
information EPA used in order to identify monitors that are 
receptors for evaluation of interference with maintenance for 
certain states in the western United States. See, Memorandum from 
Brian Timin of EPA's Office of Air Quality Planning and Standards, 
Air Quality Modeling Group entitled ``Documentation of Future Year 
Ozone and Annual PM2.5 Design Values for Western 
States,'' under ``Memorandum to Docket EPA-R08-OAR-2007-1035,'' EPA, 
August 23, 2010.
    \12\ Design Values for Western States, EPA (August 23, 2010).
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    EPA also notes that, except for Uintah County, the commenter 
provides no specific facts--such as the location of monitoring 
receptors, ozone concentrations, or time span during which high ozone 
concentrations were monitored--to support its arguments concerning 
these areas. Thus, WG has not identified any reasons that EPA

[[Page 71032]]

should consider these areas as maintenance receptors, making it 
difficult for EPA to address properly WG's concerns about interference 
with maintenance in the Wasatch Front, the Phoenix area in Arizona, 
portions of western Wyoming, or San Juan County in New Mexico. As for 
the commenter's reference to Uintah County, where in February 2010 
monitors in Ouray and Red Wash registered ozone concentrations above 
120 ppb, EPA notes that the two monitors were installed as recently as 
July 2009, and therefore their data does not provide the historical 
variability background that is an essential component for the 
identification of maintenance receptors.\13\ EPA is concerned about the 
ambient levels of ozone in this area, but at present EPA does not have 
the necessary years of data to evaluate whether this area is 
appropriate for use as a maintenance receptor for the 1997 8-hour ozone 
NAAQS in accordance with the Agency's approach to this requirement.\14\
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    \13\ See above, in EPA Response to Comment No. 1, the 
methodology used for the identification of maintenance monitors in 
the August 2, 2010 Transport Rule Proposal, and the August 23, 2010 
Western States Design Values memo. The monitor in Ouray is 
identified as Site ID number 49-047-2003, and in Red Wash as Site ID 
number 49-047-2002.
    \14\ EPA notes that the installation and operation expenses for 
the Ouray and Red Wash monitoring stations referenced above were 
funded by several companies because of court orders resulting from 
litigation initiated by EPA, affected states and tribes. See, for 
example, the Consent Decree signed by Kerr-McGee Corporation and EPA 
on May 8, and May 16, 2007, lodged May 17, 2007, and entered by the 
court on March 26, 2008.
    .
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    Comment No. 3--In its comment under section C., ``EPA has not 
Assessed New Mexico's [sic] Interference with Maintenance in the 
Present,'' WG asserts that EPA's analysis ignores whether Colorado is, 
at the present, interfering with maintenance in other States. It argues 
EPA erred by considering only whether emissions from Colorado will 
interfere with maintenance of the 1997 8-hour ozone NAAQS in areas that 
would be considered ``maintenance receptors'' as of 2012.
    WG argues that this approach is inconsistent with the approach 
taken in a previous action regarding significant contribution to 
nonattainment in other states (citing 75 FR 33174-90). The commenter 
agrees that ``EPA should ensure that Colorado does not interfere with 
maintenance or contribute significantly to nonattainment in other 
states in the future'' but argues that ``the agency's duties under 
Section 110(a)(2)(D)(i)(I) apply both in the present and the future.'' 
EPA's approach is flawed, WG concludes, because EPA identifies 
maintenance areas likely to exist by 2012 and does not identify 
interference with maintenance that currently exists. WG also asserts 
that EPA's approach ignores whether Colorado is presently interfering 
with maintenance of the 1997 8-hour ozone NAAQS in downwind states.\15\
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    \15\ Before addressing the substantive issues raised in this 
comment, we would like to clarify that we presume that the reference 
to New Mexico in the comment's title is a clerical error, and that 
the commenter intended to refer to either Colorado or North Dakota.
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    EPA Response--EPA disagrees with the commenter concerning the 
evaluation of significant contribution versus interference with 
maintenance. Section 110(a)(2)(D)(i)(I) of the Clean Air Act requires 
that a state SIP ``contain adequate provisions prohibiting * * * any 
source or other type of emission activities within the state from 
emitting any air pollutants in amount which will contribute 
significantly to nonattainment in, or interfere with maintenance by, 
any other state with respect to any [ ] national primary or secondary 
ambient air quality standard.''
    In determining the appropriate year to analyze to determine whether 
emissions from Colorado will interfere with maintenance by any other 
state, EPA used an approach upheld by the DC Circuit in North Carolina 
v. EPA. In that case, the Court examined EPA's definition of ``will'' 
in ``will contribute significantly.'' The placement of the word 
``will'' at the end of section 110(a)(2)(D)(i) clarifies that it 
applies to all of the provisions that follow--both those in 
110(a)(2)(D)(i)(I) and those in 110(a)(2)(D)(i)(II). Thus the DC 
Circuit's discussion of the meaning of the word ``will'' in ``will 
significantly contribute'' also applies to the meaning of the word will 
in ``will * * * interfere with maintenance.''
    In North Carolina v. EPA, the DC Circuit rejected North Carolina's 
argument that EPA erred in limiting its analysis of downwind areas by 
excluding areas that were currently monitored nonattainment but 
projected to be in attainment at a future date. Like WG argues here, 
North Carolina had argued that EPA was obligated to analyze the 
significant contribution of states that were contributing to areas of 
North Carolina that were in nonattainment at the time the rule was 
promulgated even though those areas were projected to come into 
attainment by the year selected for the future base case analysis. In 
rejecting this argument, the DC Circuit explained that the approach 
used by EPA was identical to the one used previously in the 
NOX SIP Call and that ``because `will' can mean either 
certainty or indicate the future tense,'' EPA's approach was 
reasonable. In other words, the court approved EPA's approach that 
entailed the evaluation of interstate transport impacts at a future 
date in time.
    Contrary to the assertions of the commenter, EPA believes that 
evaluation of interference with maintenance using a future date is the 
most appropriate approach for that requirement. As explained in the 
proposed action, the court decision affecting the CAIR rule required 
EPA to reevaluate its approach to the interfere with maintenance 
requirement of section 110(a)(2)(D) and to develop a new approach to 
give that requirement separate meaning. In doing so, EPA has developed 
an approach that necessarily requires a number of years of data, and an 
analysis that evaluates where there may be difficulties with 
maintaining attainment at a specific point in time, in this instance 
2012. In the prior action cited by WG, EPA's evaluation of whether 
emissions would significantly contribute to nonattainment in other 
states was based on the data available at the time of that evaluation 
and before EPA had developed its approach for evaluating interference 
with maintenance. It is reasonable and appropriate for EPA to use, in 
this rulemaking, the current approach to identifying maintenance 
receptors for purposes of section 110(a)(2)(D)(i) that EPA developed to 
be consistent with the direction given to EPA in North Carolina v. EPA.
    Finally, we note that comments on the validity or reasonableness of 
the approach to determining significant contribution in prior actions 
are not directly relevant to this rulemaking. This rulemaking addresses 
only the ``interfere with maintenance'' requirement of section 
110(a)(2)(D)(i). EPA published a prior proposal (75 FR 16032) and final 
rule (75 FR 31306) analyzing the Colorado SIP submission for the 
``significant contribution'' prong of section 110(a)(2)(D)(i).

III. Final Action

    EPA is partially approving the Interstate Transport SIP submitted 
by the State of Colorado on June 18, 2009. Specifically, in this action 
EPA is approving the portions of that SIP submission that address the 
requirement of Section 110(a)(2)(D)(i)(I) that emissions from sources 
in that State do not ``interfere with maintenance'' of the 1997 8-hour 
ozone NAAQS by any other state. EPA has concluded that the State's 
submission, and additional evidence evaluated by EPA, establish that

[[Page 71033]]

emissions from Colorado sources do not have such an impact on other 
states for purposes of the 1997 8-hour ozone NAAQS. Therefore, the 
State's SIP does not need to include additional substantive controls to 
reduce emissions for purposes of section 110(a)(2)(D)(i)(I) for these 
NAAQS. In a Federal Register action of June 3, 2010 EPA approved those 
portions of the Interstate Transport SIP submitted by the State of 
Colorado on June 18, 2009 addressing the requirement of Section 
110(a)(2)(D)(i)(I) that emissions from sources in that State do not 
``significantly contribute'' to violations of the 1997 8-hour ozone 
NAAQS in any other state.

IV. Statutory and Executive Order Review

    Under the Clean Air Act, the Administrator is required to approve a 
SIP submission that complies with the provisions of the Act and 
applicable Federal regulations. 42 U.S.C. 7410(k); 40 CFR 52.02(a). 
Thus, in reviewing SIP submissions, EPA's role is to approve state 
choices, provided that they meet the criteria of the Clean Air Act. 
Accordingly, this action merely approves state law as meeting Federal 
requirements and does not impose additional requirements beyond those 
imposed by state law. For that reason, this action:
     Is not a ``significant regulatory action'' subject to 
review by the Office of Management and Budget under Executive Order 
12866 (58 FR 51735, October 4, 1993);
     Does not impose an information collection burden under the 
provisions of the Paperwork Reduction Act (44 U.S.C. 3501 et seq.);
     Is certified as not having a significant economic impact 
on a substantial number of small entities under the Regulatory 
Flexibility Act (5 U.S.C. 601 et seq.);
     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);
     Does not have Federalism implications as specified in 
Executive Order 13132 (64 FR 43255, August 10, 1999);
     Is not an economically significant regulatory action based 
on health or safety risks subject to Executive Order 13045 (62 FR 
19885, April 23, 1997);
     Is not a significant regulatory action subject to 
Executive Order 13211 (66 FR 28355, May 22, 2001);
     Is not subject to requirements of Section 12(d) of the 
National Technology Transfer and Advancement Act of 1995 (15 U.S.C. 272 
note) because application of those requirements would be inconsistent 
with the Clean Air Act; and
     Does not provide EPA with the discretionary authority to 
address, as appropriate, disproportionate human health or environmental 
effects, using practicable and legally permissible methods, under 
Executive Order 12898 (59 FR 7629, February 16, 1994).
    In addition, this rule does not have tribal implications as 
specified by Executive Order 13175 (65 FR 67249, November 9, 2000), 
because the SIP is not approved to apply in Indian country located in 
the state, and EPA notes that it will not impose substantial direct 
costs on tribal governments or preempt tribal law.
    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 action and 
other required information to the U.S. Senate, 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 January 21, 2011. Filing a 
petition for reconsideration by the Administrator of this final rule 
does not affect the finality of this action 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 in 40 CFR Part 52

    Environmental protection, Air pollution control, Incorporation by 
reference, Intergovernmental relations, Nitrogen dioxide, Ozone, 
Particulate matter, Reporting and recordkeeping requirements, Volatile 
organic compounds.

    Authority:  42 U.S.C. 7401 et seq.

    Dated: November 9, 2010.
Carol Rushin,
Acting Regional Administrator, Region 8.

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40 CFR part 52 is amended as follows:

PART 52--[AMENDED]

0
1. The authority citation for part 52 continues to read as follows:

    Authority:  42 U.S.C. 7401 et seq.

Subpart G--Colorado

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2. Section 52.352 is revised to read as follows:

Sec.  52.352  Interstate transport.

    Addition to the Colorado State Implementation Plan of the Colorado 
Interstate Transport SIP regarding the 1997 8-Hour Ozone Standard for 
the ``significant contribution'' and the ``interfere with maintenance'' 
requirements, as adopted by the Colorado Air Quality Control Commission 
on December 30, 2008, State effective January 30, 2009, and submitted 
by the Governor's designee on June 18, 2009.

[FR Doc. 2010-29245 Filed 11-19-10; 8:45 am]
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