Document ID: EPA-R08-OAR-2009-0557-0006
Agency: epa
Document Type: Rule
Title: Federal Register Action.  Final Rule.  North Dakota: Interstate Transport of Pollution SIP for the 1997 PM2.5 and 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 71023-71029]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2010-29244]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52
[EPA-R08-OAR-2009-0557; FRL-9229-1]

Approval and Promulgation of State Implementation Plan Revisions; 
State of North Dakota; Interstate Transport of Pollution for the 1997 
PM2.5 and 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 the State Implementation Plan 
revisions submitted by the State of North Dakota on April 6, 2009. 
Specifically, EPA is approving the portions of the ``Interstate 
Transport of Air Pollution'' revisions addressing the ``interference 
with maintenance'' requirement of Clean Air Act (CAA) section 
110(a)(2)(D)(i) for the 1997 PM2.5 and 8-hour ozone National 
Ambient Air Quality Standards (NAAQS). The ``interference with 
maintenance'' requirement of section 110(a)(2)(D)(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-2009-0557. 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 State or North Dakota mean the State of North 
Dakota, unless the context indicates otherwise.

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, and PM2.5 NAAQS. This action does not address the 
requirements for the 2006 24- hour 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 April 6, 2009 the State of North Dakota submitted a SIP 
addressing the section 110(a)(2)(D)(i) four requirements, noted above, 
for the 1997 8-hour ozone NAAQS and for the 1997 annual and 24-hour 
PM2.5 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 ozone and PM2.5 NAAQS by any other 
state.
    On August 15, 2006, EPA issued its ``Guidance for State 
Implementation Plan (SIP) Submissions 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 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 ozone NAAQS and 
1997 PM2.5 NAAQS.
    In a Federal Register action dated September 17, 2010, EPA proposed 
approval of the North Dakota Interstate Transport SIP portions 
addressing the interference with maintenance requirement of section 
110(a)(2)(D)(i). EPA concluded in its proposed action that the various 
factual and technical considerations supported a determination that 
emissions from North Dakota do not interfere with maintenance by any 
states with areas at risk for maintenance of the 1997 8-hour ozone 
NAAQS or for maintenance of the 1997 annual and 24-hour 
PM2.5 NAAQS.
    EPA did not receive comments that persuade the Agency that there is 
such interference with maintenance for the 1997 ozone or 
PM2.5 NAAQS and thus in today's final action EPA is making a 
final regulatory determination that North Dakota's sources do not 
interfere with maintenance of the 1997 8-hour ozone NAAQS, and the 1997 
PM2.5 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 identifiable under sections A., B., 
and C., and is accessible online at regulations.gov under Docket No. 
EPA-R08-OAR-2009-0057. Later in this section EPA responds to the 
significant

[[Page 71024]]

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 the Colorado and the North 
Dakota interstate transport SIPs. For clarity, however, in this action 
EPA will address WG's comments as if they were directed only to the 
proposed rule action for North Dakota (75 FR 56928).\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 Colorado ``interference with maintenance'' requirement we 
address WG's comments as if they were directed to the proposed rule 
action for Colorado (75 FR 56935).
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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 * * * North Dakota [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 DC Circuit in 
North Carolina v. EPA, 531 F.3d 896 (DC Cir. 2008).\2\ In that case, 
the court analyzed the definition of ``interfere with maintenance'' 
used in the Clean Air Interstate Rule (CAIR). 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) 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 North Dakota 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 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 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 North Dakota Interstate Transport SIP (75 FR 56928).
    \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 45210, 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

[[Page 71025]]

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 D.C. 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 North Dakota'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 cited a variety of information suggesting that that 
receptors in the Denver Metropolitan Area/North Front Range (DMA/NFR) 
area should also be considered for maintenance purposes under 
110(a)(2)(D)(i) in this action. The commenter points out that EPA 
itself has stated, ``Data for 2005-2007 and 2006-2008 reflect 
violations of the 8-hour ozone NAAQS at the Rocky Flats North monitor 
(values of [0.085] and 0.086 ppm, respectively).'' The commenter also 
argued that modeling prepared in conjunction with Colorado's DMA/NFR 
attainment demonstration shows that by 2010, the three-year design 
value is only projected to be lowered to 0.084 parts per million, 
barely in compliance with the NAAQS, and that certain portions of the 
DMA/NFR area of Colorado would violate the 1997 ozone NAAQS in 2010 at 
grid cells west of Fort Collins. The commenter referenced several 
documents that are part of the Colorado's DMA/NFR 8-hour Ozone 
Attainment Demonstration in support of its arguments. The commenter 
cited the report's language that indicated that the modeling projection 
of a value above the 1997 8-hour standard to the west of Fort Collins 
is not ``implausible'' and explaining, ``In the case of the Denver 
ozone modeling, higher ozone concentrations are estimated west of Fort 
Collins than at the locations of the two monitors in Fort Collins on 
some days and this does not appear to be an error in the modeling 
system.'' \9\ Finally, the commenter argued that EPA's failure to 
consider the DMA/NFR area as a receptor for evaluating interference 
with maintenance in this action reflects the very problem that the D.C. 
Circuit warned could result without giving independent meaning to the 
term ``interfere with maintenance.'' \10\
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    \9\ The commenter referenced the Colorado Department of Public 
Health and Environment's ``2010 Ozone Attainment Demonstration 
Modeling for the Denver 8-hour Ozone State Implementation Plan 
Control Strategy'' and the Environ modeling report ``Final 2010 
Ozone Attainment Demonstration Modeling for the Denver 8-hour Ozone 
State Implementation Plan.''
    \10\ This comment also expresses concern about the Wasatch Front 
and Uinta County areas in Utah, the Phoenix area of Arizona, 
portions of western Wyoming, and Juan County in New Mexico as at 
risk for maintenance for the 1997 8-hour ozone NAAQS. According to 
WG, the proposed EPA's September 17, 2010 proposed rule assessment 
of the Colorado's emissions impacts on maintenance of the NAAQS by 
other states should have included the evaluation of Colorado 
emissions on the areas noted above. We respond to that portion of 
this comment in the final rulemaking for the Colorado interstate 
transport SIP submitted June 18, 2009.
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    EPA's Response--EPA disagrees with WG's argument that EPA has 
inappropriately identified the correct monitors for maintenance 
receptors. As discussed in greater detail in the previous response to 
comment no. 1, EPA has selected a method that identifies maintenance 
receptors separately from nonattainment receptors and gives an 
independent meaning to the interfere with maintenance prong of section 
110(a)(2)(D)(i). EPA has consistently applied this method to all 
potential receptors in States potentially impacted by North Dakota's 
emissions including those in the DMA/NFR area.
    The commenter's argument EPA did not consistently identify 
maintenance receptors is premised on the same fundamental 
misunderstanding discussed in response to comment no. 1--that EPA's 
identification of nonattainment receptors was based on current or past 
NAAQS violations. As explained above, this is not correct. EPA did not 
base its identification of maintenance receptors on an analysis of 
whether air quality at those receptors exceeded the NAAQS in the base 
years. The methodology EPA used to identify maintenance areas takes 
into account historic variability of emissions at specific monitoring 
sites to analyze whether or not monitoring sites projected to be in 
attainment in 2012 will nonetheless remain at risk of slipping into 
nonattainment in that year. The commenter provided a number of modeling 
or monitoring analyses for 2010 or earlier. As we have addressed in 
responses elsewhere in this notice, EPA continues to believe 2012 is 
the appropriate year for this analysis. Thus, modeling or monitoring 
data for other years is not directly relevant to this rulemaking. 
Nonetheless, below we address the commenter's specific assertions about 
the monitoring and modeling.
    The commenter asserts that monitoring data for 2005-07 and 2006-08 
for the Rocky Flats North monitor reflect violations of the 8-hour 
NAAQS and therefore EPA should consider this Rocky Flats North monitor 
as a ``maintenance receptor.'' The commenter further cites to modeling 
prepared in conjunction with Colorado's DMA/NFR attainment 
demonstration to support its assertion that EPA has applied 
inconsistently its definition of interference with maintenance. The 
modeling data referenced by the commenter, however, only identifies 
monitors that, in the commenter's view, are at risk of being in 
nonattainment or having maintenance problems in 2010. The monitoring 
data cited indicates high ozone levels in the past. The underlying 
issue raised is thus 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 or in the past. 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.
    EPA's method is based on model projection values that take into 
account multi-year variability in ozone data at specific monitors. For 
identification of maintenance receptors, EPA utilized the monitoring 
data from the 2003-2007

[[Page 71026]]

period to calculate 2012 future year modeling design value projections. 
The 2003-07 period includes three Design Value (DV) periods (2003-2005, 
2004-2006, and 2005-2007). The 2012 future year DVs were calculated by 
multiplying a 3-year DV (base year) by the ratio of the Future Year 
average of the daily 8-hour ozone maximums around a monitor over the 
Base Year average of the daily 8-hour ozone maximums around a monitor. 
This calculation was performed for each of the three 3-year DVs (2003-
2005, 2004-2006, and 2005-2007). This approach yielded three different 
projected 2012 design values and thus, tests for variability in 
meteorology. If any of the three 2012 projections was above the 1997 
ozone standard, then the receptor would be considered a maintenance 
receptor. None of the 2012 projections for the DMA/NFR area was above 
the standard so the area was not considered a maintenance area. This 
approach was the same as the approach used for every potential receptor 
evaluated. It is worth noting that EPA's analysis included the 2005-
2007 data for the Rocky Flats monitor (which is one of the highest 
monitored DVs in recent years for this monitor) that the commenter 
raised as a concern and pursuant to its methodology as previously 
described EPA's analysis determined that the Rocky Flats monitor would 
not be a maintenance receptor in 2012.
    Further, EPA disagrees with commenter's conclusion that the 
modeling performed for the DMA/NFR attainment demonstration with the 
2010 model projections establishes that any of the areas identified 
will have maintenance problems for the 1997 8-hour ozone NAAQS. We 
disagree with WG's conclusion that the DMA/NFR area monitors should be 
identified as ``maintenance receptors'' in large part because it bases 
its conclusion on projections for 2010 instead of 2012. This modeling 
used projections for 2010 not 2012, which as explained above and in 
response to comment no. 3 below is not the correct year for comparison, 
given the approach EPA has developed for determining maintenance 
receptors. EPA's analysis of maintenance receptors, which is based on 
the approach developed in the Transport Rule Proposal to be consistent 
with the D.C. Circuit's opinion in North Carolina v. EPA and uses 
projections for 2012, did not identify any maintenance receptors in the 
DMA/NFR area. This conclusion is consistent with evidence suggesting 
emissions are likely to trend downward (for example, with two more 
years of fleet turnover, this modeling would likely have projected 
lower levels of ozone in 2012) and preliminary monitoring data for 
2010, which indicates that the DMA/NFR area is meeting the 1997 ozone 
standard. Further, EPA has reviewed Colorado's attainment demonstration 
for the DMA/NFR area and proposed that the combination of the modeling 
and Weight of Evidence analyses demonstrates that Denver will be in 
attainment in 2010.\11\
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    \11\ EPA's ``Guidance on the Use of Models and Other Analyses 
for Demonstrating Attainment of Air Quality Goals for Ozone, 
PM2.5, and Regional Haze,'' EPA-454/B-07-002, April 2007. 
Also, 75 FR 42346 (July 21, 2010) [EPA-R08-OAR-2010-0285; FRL-9177-
2], Proposed Rule, ``Approval and Promulgation of Air Quality 
Implementation Plans; Colorado; Attainment Demonstration for the 
1997 8-Hour Ozone Standard, and Approval of Related Revisions''; at 
42346-61.
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    In addition, the commenter's concern that an area west of Fort 
Collins, might exceed 84 ppb in 2010 is based on exceedance values in 
the Colorado modeling analysis from a special analysis, called the 
Unmonitored Area Analysis (UAA), that is recommended for model grid 
cells that are not analyzed in the monitor based attainment 
demonstration because they are not located near a monitor. EPA does not 
believe that the UAA establishes that this area should be considered a 
maintenance receptor area for the purposes of 110(a)(2)(D)(i).
    First, the UAA analysis is for 2010, which as noted above is not 
the correct analysis year. Second, EPA guidance indicates that NAAQS 
violations in the UAA should be handled on a case by case basis.\12\ 
The guidance stresses that due to the lack of measured data, the 
examination of ozone concentrations as part of the unmonitored area 
analysis is more uncertain than the monitor based attainment test. This 
is true even in situations such as this where, as the commenter points 
out; no known errors were identified by the contractor in the modeling 
analysis. As a result, the UAA results are recommended to be treated as 
a separate test from the monitor based attainment test with less weight 
put on the conclusions of the UAA analysis. EPA's attainment 
demonstration guidance indicates, ``While it is expected that States 
will implement additional emission controls to eliminate predicted 
violations of the monitor based test, the same requirements may not be 
appropriate in unmonitored areas.'' \13\ The guidance recommends that 
it may be appropriate to deploy additional monitors in an area where 
the unmonitored analysis indicates a potential future year violation.
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    \12\ Id.
    \13\ Id. at 32.
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    To address the concerns raised by the UAA, Colorado installed an 
additional ozone monitor in the area West of Fort Collins to determine 
whether the model predicted ozone concentrations are, in fact, valid. 
The special purpose monitor, located in Rist Canyon, began operation on 
May 14, 2009. The Rist Canyon monitoring station has collected data for 
two ozone seasons (approximately 16 months) since it began operating 
and the fourth highest daily maximum 8-hour average ozone concentration 
reading is 69 ppb for May through December of 2009 and 72 ppb for 
January through August 2010.\14\
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    \14\ The Rist Canyon monitoring station uses a Federal 
Equivalent Method (FEM) and follows the quality assurance 
requirements of 40 CFR Part 58 Appendix A. Ozone data collected at 
this monitoring station is eligible for comparison to the ozone 
NAAQS after the monitor has operated for more than 24 months per 40 
CFR 58.30(c). Design values, however, are based on the 3-year 
average of the annual fourth highest daily maximum 8-hour average 
ozone concentration (see 40 CFR part 50, Appendix D).
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    Therefore, EPA does not believe the modeling performed for the 
State of Colorado's Denver/NFR area SIP can support the conclusion that 
this area should be considered a maintenance receptor area for the 
purposes of 110(a)(2)(D)(i). The methodology developed to identify 
maintenance receptors for the purpose of analyzing interference with 
maintenance with respect to the 1997 ozone and PM2.5 NAAQS 
relies on base period monitoring data to identify monitor locations 
that are projected to have maintenance problems in 2012. The 
methodology does not identify receptors based on modeling data alone. 
While the monitor has not operated long enough to account for 
variability in ozone levels, the newly installed monitor in the 
relevant area is reading well below the standard and this fact further 
confirms that the modeling results and the UAA results do not support 
the conclusion that receptors in the DMA/NFR area should be considered 
maintenance receptors for the purpose of CAA section 110(a)(2)(D)(i).
    In conclusion, EPA disagrees with the commenter. We have used a 
fully consistent approach in identifying areas that may have difficulty 
in maintaining attainment of the NAAQS. It is these areas that we have 
further evaluated to see if North Dakota's emissions would interfere 
with maintenance of the NAAQS.
    Comment No. 3--In its comment under section C., ``EPA has not 
Assessed New Mexico's [sic] Interference with

[[Page 71027]]

Maintenance in the Present,'' WG asserts that EPA's analysis ignores 
whether North Dakota is, at the present, interfering with maintenance 
of the 1997 8-hour ozone NAAQS, and the 1997 PM2.5 NAAQS, in 
other States. It argues EPA erred by considering only whether emissions 
from North Dakota will interfere with maintenance in areas that by 2012 
would be considered ``maintenance receptors.''
    WG argues that this approach is inconsistent with the approach 
taken to determine whether New Mexico significantly contributes to 
nonattainment in other States (citing 75 FR 33174-33190) and that this 
alleged inconsistent application ``raises serious concerns that EPA is 
again simply finding excuses to avoid requiring North Dakota to do its 
part to limit air pollution that adversely affects neighboring states, 
including Colorado.'' They agree that ``EPA should ensure that North 
Dakota does not interfere with maintenance or contribute significantly 
to nonattainment in other states in the future'' but argue 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 maintenance areas that currently exist. WG also asserts that 
EPA's approach ignores whether North Dakota 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 North Dakota 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 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 16026) and final rule (75 FR 
31290) analyzing the North Dakota SIP submission for the ``significant 
contribution'' prong of section 110(a)(2)(D)(i).

III. Final Action

    The Environmental Protection Agency is approving portions of the 
Interstate Transport of Air Pollution SIP submitted by the State of 
North Dakota on April 6, 2009. Specifically, in this action EPA is 
approving the language in Section 7.8.1, subsection B., ``Nonattainment 
and Maintenance Area Impact,'' that specifically addresses element (2) 
of section 110(a)(2)(D)(i), the requirement that the SIP contain 
adequate provisions prohibiting emissions from North Dakota from 
interfering with maintenance of the NAAQS by any other state. EPA has 
concluded that the evidence evaluated by EPA establishes that emissions 
from North Dakota sources do not interfere with maintenance of the 1997 
8-hour ozone or the 1997 PM2.5 NAAQS in any other state. 
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.

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

[[Page 71028]]

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, Carbon monoxide, 
Incorporation by reference, Intergovernmental relations, Lead, Nitrogen 
dioxide, Ozone, Particulate matter, Reporting and recordkeeping 
requirements, Sulfur oxides, Volatile organic compounds.

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

    Dated: November 10, 2010.
James B. Martin,
Regional Administrator, Region 8.

0
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 JJ--North Dakota

0
2. Section 52.1820 is amended in the table in paragraph (e) by revising 
the entry in ``(1)'' and adding entry ``(22)'' in numerical order to 
read as follows:

Sec.  52.1820  Identification of plan.

* * * * *
    (e) * * *

----------------------------------------------------------------------------------------------------------------
                                     Applicable
   Name of nonregulatory SIP       geographic or     State submittal   EPA approval date
           provision               non-attainment     date/ adopted      and citation 3        Explanations
                                        area               date
----------------------------------------------------------------------------------------------------------------
 (1) Implementation Plan for     Statewide........  Submitted: 1/24/   5/31/72, 37 FR     Excluding subsequent
 the Control of Air Pollution                        72; Adopted: 1/    10842.             revisions, as
 for the State of North Dakota.                      24/72.                                follows: Chapters 1,
                                                                                           2, 6, 7, 9, 11, and
                                                                                           12; Sections 2.11,
                                                                                           3.7, 6.8, 6.10, 6.11,
                                                                                           6.13, 7.7, and 8.3;
                                                                                           subsections 7.8.1.B.,
                                                                                           7.8.1.D., and 8.3.1.
                                                                                           Revisions to these
                                                                                           non-regulatory
                                                                                           provisions have
                                                                                           subsequently been
                                                                                           approved. See below.
Chapters.......................  .................  Clarification      With all
1. Introduction................                      submitted: 6/14/   clarifications:
2. Legal Authority.............                      73; 2/19/74; 6/    3/2/76; 41 FR
3. Control Strategy............                      26/74; 11/21/74;   8956.
4. Compliance Schedule.........                      4/23/75.
    5. Prevention of Air
     Pollution Emergency
     Episodes.
    7. Review of New Sources
     and Modifications.
    8. Source Surveillance.....
    9. Resources...............
    10. Inter-governmental
     Cooperation.
    11. Rules and Regulations..
With subsequent revisions to
 the chapters as follows:
 

[[Page 71029]]

 
                                                  * * * * * * *
(22) Section 7.8, Interstate     Statewide........  Submitted: 4/09/   11/22/10 [insert   Includes portions of
 Transport of Air Pollution                          09; Adopted: 4/    FR page number     Subsection 7.8.1.B.,
 (only portion of 7.8.1.B.).                         01/09.             where document     ``Nonattainment and
                                                                        begins].           Maintenance Area
                                                                                           Impact,'' that
                                                                                           specifically address
                                                                                           the ``interference
                                                                                           with maintenance''
                                                                                           requirement of CAA
                                                                                           Section
                                                                                           110(a)(2)(D)(i).
----------------------------------------------------------------------------------------------------------------
\3\ In order to determine the EPA effective date for a specific provision listed in this table, consult the
  Federal Register notice cited in this column for the particular pro

[FR Doc. 2010-29244 Filed 11-19-10; 8:45 am]
BILLING CODE 6560-50-P