[Federal Register Volume 76, Number 134 (Wednesday, July 13, 2011)]
[Rules and Regulations]
[Pages 41123-41135]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-17467]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[EPA-R04-OAR-2010-0722-201125 FRL-9436-6]


Approval and Promulgation of Implementation Plans; Mississippi; 
110(a)(1) and (2) Infrastructure Requirements for the 1997 8-Hour Ozone 
National Ambient Air Quality Standards

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is taking final action to approve the December 7, 2007, 
submission by the State of Mississippi, through the Mississippi 
Department of Environmental Quality (MDEQ) as demonstrating that the 
State meets the implementation plan (SIP) requirements of sections 
110(a)(1) and (2) of the Clean Air Act (CAA or the Act) for the 1997 8-
hour ozone national ambient air quality standards (NAAQS). Section 
110(a) of the CAA requires that each state adopt and submit a SIP for 
the implementation, maintenance, and enforcement of each NAAQS 
promulgated by the EPA, which is commonly referred to as an 
``infrastructure'' SIP. Mississippi certified that the Mississippi SIP 
contains provisions that ensure the 1997 8-hour ozone NAAQS is 
implemented, enforced, and maintained in Mississippi (hereafter 
referred to as ``infrastructure submission''). Mississippi's 
infrastructure submission, provided to EPA on December 7, 2007, 
addressed all the required infrastructure elements for the 1997 8-hour 
ozone NAAQS. Additionally, EPA is responding to adverse comments 
received on EPA's March 17, 2011, proposed approval of Mississippi's 
December 7, 2007, infrastructure submission.

DATES: Effective Date: This rule will be effective August 12, 2011.

ADDRESSES: EPA has established a docket for this action under Docket 
Identification No. EPA-R04-OAR-2010-0722. 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, i.e., 
Confidential Business Information 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 Regulatory Development Section, Air Planning 
Branch, Air, Pesticides and Toxics Management Division, U.S. 
Environmental Protection Agency, Region 4, 61 Forsyth Street, SW., 
Atlanta, Georgia 30303-8960. EPA requests that if at all possible, you 
contact the person listed in the FOR FURTHER INFORMATION CONTACT 
section to schedule your inspection. The Regional Office's official 
hours of business are Monday through Friday, 8:30 to 4:30 excluding 
Federal holidays.

FOR FURTHER INFORMATION CONTACT: Nacosta C. Ward, Regulatory 
Development Section, Air Planning Branch, Air, Pesticides and Toxics 
Management Division, U.S. Environmental Protection Agency, Region 4, 61 
Forsyth Street, SW., Atlanta, Georgia 30303-8960. The telephone number 
is (404) 562-9140. Ms. Ward can be reached via electronic mail at 
[email protected].

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Background
II. Scope of Infrastructure SIPs
III. This Action
IV. EPA's Response to Comments
V. Final Action
VI. Statutory and Executive Order Reviews

I. Background

    Upon promulgation of a new or revised NAAQS, sections 110(a)(1) and 
(2) of the CAA require states to address basic SIP requirements, 
including emissions inventories, monitoring, and modeling to assure 
attainment and maintenance for that new NAAQS. On July 18, 1997, EPA 
promulgated a new NAAQS for ozone based on 8-hour average 
concentrations, thus states were required to provide submissions to 
address sections 110(a)(1) and (2) of the CAA for this new NAAQS. 
Mississippi provided its infrastructure submission for the 1997 8-hour 
ozone NAAQS on

[[Page 41124]]

December 7, 2007. On March 17, 2011, EPA proposed to approve 
Mississippi's December 7, 2007, infrastructure submission for the 1997 
8-hour ozone NAAQS. See 76 FR 14631. A summary of the background for 
today's final action is provided below. See EPA's March 17, 2011, 
proposed rulemaking at 76 FR 14631 for more detail.
    Section 110(a) of the CAA requires states to submit SIPs to provide 
for the implementation, maintenance, and enforcement of a new or 
revised NAAQS within three years following the promulgation of such 
NAAQS, or within such shorter period as EPA may prescribe. Section 
110(a) imposes the obligation upon states to make a SIP submission to 
EPA for a new or revised NAAQS, but the contents of that submission may 
vary depending upon the facts and circumstances. In particular, the 
data and analytical tools available at the time the state develops and 
submits the SIP for a new or revised NAAQS affects the content of the 
submission. The contents of such SIP submissions may also vary 
depending upon what provisions the state's existing SIP already 
contains. In the case of the 1997 8-hour ozone NAAQS, states typically 
have met the basic program elements required in section 110(a)(2) 
through earlier SIP submissions in connection with previous ozone 
NAAQS.
    More specifically, section 110(a)(1) provides the procedural and 
timing requirements for SIPs. Section 110(a)(2) lists specific elements 
that states must meet for ``infrastructure'' SIP requirements related 
to a newly established or revised NAAQS. As mentioned above, these 
requirements include SIP infrastructure elements such as modeling, 
monitoring, and emissions inventories that are designed to assure 
attainment and maintenance of the NAAQS. The requirements that are the 
subject of this final rulemaking are listed below \1\ and in EPA's 
October 2, 2007, memorandum entitled ``Guidance on SIP Elements 
Required Under Section 110(a)(1) and (2) for the 1997 8-Hour Ozone and 
PM2.5 National Ambient Air Quality Standards.''
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    \1\ Two elements identified in section 110(a)(2) are not 
governed by the three-year submission deadline of section 110(a)(1) 
because SIPs incorporating necessary local nonattainment area 
controls are not due within three years after promulgation of a new 
or revised NAAQS, but rather are due at the time the nonattainment 
area plan requirements are due pursuant to section 172. These 
requirements are: (1) Submissions required by section 110(a)(2)(C) 
to the extent that subsection refers to a permit program as required 
in part D Title I of the CAA, and (2) submissions required by 
section 110(a)(2)(I) which pertain to the nonattainment planning 
requirements of part D, Title I of the CAA. Today's final rulemaking 
does not address infrastructure elements related to section 
110(a)(2)(I) but does provide detail on how Mississippi's SIP 
addresses 110(a)(2)(C).
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     110(a)(2)(A): Emission limits and other control measures.
     110(a)(2)(B): Ambient air quality monitoring/data system.
     110(a)(2)(C): Program for enforcement of control 
measures.\2\
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    \2\ This rulemaking only addresses requirements for this element 
as they relate to attainment areas.
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     110(a)(2)(D): Interstate transport.\3\
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    \3\ Today's final rule does not address element 110(a)(2)(D)(i) 
(Interstate Transport) for the 1997 8-hour ozone NAAQS. Interstate 
transport requirements were formerly addressed by Mississippi 
consistent with the Clean Air Interstate Rule (CAIR). On December 
23, 2008, CAIR was remanded by the DC Circuit Court of Appeals, 
without vacatur, back to EPA. See North Carolina v. EPA, 531 F.3d 
896 (DC Cir. 2008). Prior to this remand, EPA took final action to 
approve Mississippi's SIP revision, which was submitted to comply 
with CAIR. See 72 FR 56268 (October 3, 2007). In so doing, 
Mississippi's CAIR SIP revision addressed the interstate transport 
provisions in Section 110(a)(2)(D)(i) for the 1997 8-hour ozone 
NAAQS. In response to the remand of CAIR, EPA has since proposed a 
new rule to address the interstate transport of NOX and 
SOX in the eastern United States. See 75 FR 45210 (Aug. 
2, 2010) (``the Transport Rule''). However, because this rule has 
yet to be finalized, EPA's action on element 110(a)(2)(D)(i) will be 
addressed in a separate action.
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     110(a)(2)(E): Adequate resources.
     110(a)(2)(F): Stationary source monitoring system.
     110(a)(2)(G): Emergency power.
     110(a)(2)(H): Future SIP revisions.
     110(a)(2)(I): Areas designated nonattainment and meet the 
applicable requirements of part D.\4\
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    \4\ This requirement was inadvertently omitted from EPA's 
October 2, 2007, memorandum entitled ``Guidance on SIP Elements 
Required Under Section 110(a)(1) and (2) for the 1997 8-Hour Ozone 
and PM2.5 National Ambient Air Quality Standards,'' but 
as previously discussed is not relevant to today's final rulemaking.
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     110(a)(2)(J): Consultation with government officials; 
public notification; and PSD and visibility protection.
     110(a)(2)(K): Air quality modeling/data.
     110(a)(2)(L): Permitting fees.
     110(a)(2)(M): Consultation/participation by affected local 
entities.

II. Scope of Infrastructure SIPs

    EPA is currently acting upon SIPs that address the infrastructure 
requirements of CAA section 110(a)(1) and (2) for ozone and PM2.5 NAAQS 
for various states across the country. Commenters on EPA's recent 
proposals for some states raised concerns about EPA statements that it 
was not addressing certain substantive issues in the context of acting 
on the infrastructure SIP submissions.\5\ The Commenters specifically 
raised concerns involving provisions in existing SIPs and with EPA's 
statements that it would address two issues separately and not as part 
of actions on the infrastructure SIP submissions: (i) Existing 
provisions related to excess emissions during periods of start-up, 
shutdown, or malfunction (``SSM'') at sources, that may be contrary to 
the CAA and EPA's policies addressing such excess emissions; and (ii) 
existing provisions related to ``director's variance'' or ``director's 
discretion'' that purport to permit revisions to SIP approved emission 
limits with limited public process or without requiring further 
approval by EPA, that may be contrary to the CAA. EPA notes that there 
are two other substantive issues for which EPA likewise stated that it 
would respond separately: (i) Existing provisions for minor source new 
source review programs that may be inconsistent with the requirements 
of the CAA and EPA's regulations that pertain to such programs (``minor 
source NSR''); and (ii) existing provisions for Prevention of 
Significant Deterioration programs that may be inconsistent with 
current requirements of EPA's ``Final NSR Improvement Rule,'' 67 FR 
80186 (December 31, 2002), as amended by 72 FR 32526 (June 13, 2007) 
(``NSR Reform''). In light of the comments, EPA now believes that its 
statements in various proposed actions on infrastructure SIPs with 
respect to these four individual issues should be explained.
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    \5\ See, Comments of Midwest Environmental Defense Center, dated 
May 31, 2011. Docket EPA-R05-OAR-2007-1179 (adverse 
comments on proposals for three states in Region 5). EPA notes that 
these public comments on another proposal are not relevant to this 
rulemaking and do not have to be directly addressed in this 
rulemaking. EPA will respond to these comments in the appropriate 
rulemaking action to which they apply.
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    EPA intended the statements in the proposals concerning these four 
issues merely to be informational, and to provide general notice of the 
potential existence of provisions within the existing SIPs of some 
states that might require future corrective action. EPA did not want 
states, regulated entities, or members of the public to be under the 
misconception that the Agency's approval of the infrastructure SIP 
submission of a given state should be interpreted as a reapproval of 
certain types of provisions that might exist buried in the larger 
existing SIP for such state. Thus, for example, EPA explicitly noted 
that the Agency believes that some states may have existing SIP-
approved SSM provisions that are contrary to the CAA and EPA policy, 
but that ``in this rulemaking, EPA is not proposing to approve or 
disapprove any

[[Page 41125]]

existing State provisions with regard to excess emissions during SSM of 
operations at facilities.'' EPA further explained, for informational 
purposes, that ``EPA plans to address such State regulations in the 
future.'' EPA made similar statements, for similar reasons, with 
respect to the director's discretion, minor source NSR, and NSR Reform 
issues. EPA's objective was to make clear that approval of an 
infrastructure SIP for these ozone and PM2.5 NAAQS should 
not be construed as explicit or implicit reapproval of any existing 
provisions that relate to these four substantive issues.
    Unfortunately, the Commenters and others evidently interpreted 
these statements to mean that EPA considered action upon the SSM 
provisions and the other three substantive issues to be integral parts 
of acting on an infrastructure SIP submission, and therefore that EPA 
was merely postponing taking final action on the issue in the context 
of the infrastructure SIPs. This was not EPA's intention. To the 
contrary, EPA only meant to convey its awareness of the potential for 
certain types of deficiencies in existing SIPs, and to prevent any 
misunderstanding that it was reapproving any such existing provisions. 
EPA's intention was to convey its position that the statute does not 
require that infrastructure SIPs address these specific substantive 
issues in existing SIPs and that these issues may be dealt with 
separately, outside the context of acting on the infrastructure SIP 
submission of a state. To be clear, EPA did not mean to imply that it 
was not taking a full final agency action on the infrastructure SIP 
submission with respect to any substantive issue that EPA considers to 
be a required part of acting on such submissions under section 110(k) 
or under section 110(c). Given the confusion evidently resulting from 
EPA's statements, however, we want to explain more fully the Agency's 
reasons for concluding that these four potential substantive issues in 
existing SIPs may be addressed separately.
    The requirement for the SIP submissions at issue arises out of CAA 
section 110(a)(1). That provision requires that states must make a SIP 
submission ``within 3 years (or such shorter period as the 
Administrator may prescribe) after the promulgation of a national 
primary ambient air quality standard (or any revision thereof)'' and 
that these SIPs are to provide for the ``implementation, maintenance, 
and enforcement'' of such NAAQS. Section 110(a)(2) includes a list of 
specific elements that ``[e]ach such plan'' submission must meet. EPA 
has historically referred to these particular submissions that states 
must make after the promulgation of a new or revised NAAQS as 
``infrastructure SIPs.'' This specific term does not appear in the 
statute, but EPA uses the term to distinguish this particular type of 
SIP submission designed to address basic structural requirements of a 
SIP from other types of SIP submissions designed to address other 
requirements, such as ``nonattainment SIP'' submissions required to 
address the nonattainment planning requirements of part D, ``regional 
haze SIP'' submissions required to address the visibility protection 
requirements of CAA section 169A, new source review permitting program 
submissions required to address the requirements of part D, and a host 
of other specific types of SIP submissions that address other specific 
matters.
    Although section 110(a)(1) addresses the timing and general 
requirements for these infrastructure SIPs, and section 110(a)(2) 
provides more details concerning the required contents of these 
infrastructure SIPs, EPA believes that many of the specific statutory 
provisions are facially ambiguous. In particular, the list of required 
elements provided in section 110(a)(2) contains a wide variety of 
disparate provisions, some of which pertain to required legal 
authority, some of which pertain to required substantive provisions, 
and some of which pertain to requirements for both authority and 
substantive provisions.\6\ Some of the elements of section 110(a)(2) 
are relatively straightforward, but others clearly require 
interpretation by EPA through rulemaking, or recommendations through 
guidance, in order to give specific meaning for a particular NAAQS.\7\
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    \6\ For example, section 110(a)(2)(E) provides that states must 
provide assurances that they have adequate legal authority under 
state and local law to carry out the SIP; section 110(a)(2)(C) 
provides that states must have a substantive program to address 
certain sources as required by part C of the CAA; section 
110(a)(2)(G) provides that states must have both legal authority to 
address emergencies and substantive contingency plans in the event 
of such an emergency.
    \7\ For example, section 110(a)(2)(D)(i) requires EPA to ensure 
that each state's SIP contains adequate provisions to prevent 
significant contribution to nonattainment of the NAAQS in other 
states. This provision contains numerous terms that require 
substantial rulemaking by EPA in order to determine such basic 
points as what constitutes significant contribution. See, e.g., 
``Rule To Reduce Interstate Transport of Fine Particulate Matter and 
Ozone (Clean Air Interstate Rule); Revisions to Acid Rain Program; 
Revisions to the NOX SIP Call; Final Rule,'' 70 FR 25162 
(May 12, 2005) (defining, among other things, the phrase 
``contribute significantly to nonattainment'').
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    Notwithstanding that section 110(a)(2) states that ``each'' SIP 
submission must meet the list of requirements therein, EPA has long 
noted that this literal reading of the statute is internally 
inconsistent, insofar as section 110(a)(2)(I) pertains to nonattainment 
SIP requirements that could not be met on the schedule provided for 
these SIP submissions in section 110(a)(1).\8\ This illustrates that 
EPA must determine which provisions of section 110(a)(2) may be 
applicable for a given infrastructure SIP submission. Similarly, EPA 
has previously decided that it could take action on different parts of 
the larger, general ``infrastructure SIP'' for a given NAAQS without 
concurrent action on all subsections, such as section 110(a)(2)(D)(i), 
because the Agency bifurcated the action on these latter ``interstate 
transport'' provisions within section 110(a)(2) and worked with states 
to address each of the four prongs of section 110(a)(2)(D)(i) with 
substantive administrative actions proceeding on different tracks with 
different schedules.\9\ This illustrates that EPA may conclude that 
subdividing the applicable requirements of section 110(a)(2) into 
separate SIP actions may sometimes be appropriate for a given NAAQS 
where a specific substantive action is necessitated, beyond a mere 
submission addressing basic structural aspects of the state's SIP. 
Finally, EPA notes that not every element of section 110(a)(2) would be 
relevant, or as relevant, or relevant in the same way, for each new or 
revised NAAQS and the attendant infrastructure SIP submission for that 
NAAQS. For example, the monitoring requirements that might be necessary 
for purposes of section 110(a)(2)(B) for one NAAQS could be very 
different than what might be necessary for a different pollutant. Thus, 
the content of an infrastructure SIP submission to meet this element 
from a state might be very different for an entirely new NAAQS, versus 
a minor revision to an existing NAAQS.\10\
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    \8\ See, e.g., id., 70 FR 25162, at 25163-25165 (May 12, 2005) 
(explaining relationship between timing requirement of section 
110(a)(2)(D) versus section 110(a)(2)(I)).
    \9\ EPA issued separate guidance to states with respect to SIP 
submissions to meet section 110(a)(2)(D)(i) for the 1997 ozone and 
1997 PM2.5 NAAQS. See, ``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,'' from 
William T. Harnett, Director Air Quality Policy Division OAQPS, to 
Regional Air Division Director, Regions I-X, dated August 15, 2006.
    \10\ For example, implementation of the 1997 PM2.5 
NAAQS required the deployment of a system of new monitors to measure 
ambient levels of that new indicator species for the new NAAQS.

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[[Page 41126]]

    Similarly, EPA notes that other types of SIP submissions required 
under the statute also must meet the requirements of section 110(a)(2), 
and this also demonstrates the need to identify the applicable elements 
for other SIP submissions. For example, nonattainment SIPs required by 
part D likewise have to meet the relevant subsections of section 
110(a)(2) such as section 110(a)(2)(A) or (E). By contrast, it is clear 
that nonattainment SIPs would not need to meet the portion of section 
110(a)(2)(C) that pertains to part C (i.e., the PSD requirement 
applicable in attainment areas). Nonattainment SIPs required by part D 
also would not need to address the requirements of section 110(a)(2)(G) 
with respect to emergency episodes, as such requirements would not be 
limited to nonattainment areas. As this example illustrates, each type 
of SIP submission may implicate some subsections of section 110(a)(2) 
and not others.
    Given the potential ambiguity of the statutory language of section 
110(a)(1) and (2), EPA believes that it is appropriate for EPA to 
interpret that language in the context of acting on the infrastructure 
SIPs for a given NAAQS. Because of the inherent ambiguity of the list 
of requirements in section 110(a)(2), EPA has adopted an approach in 
which it reviews infrastructure SIPs against this list of elements ``as 
applicable.'' In other words, EPA assumes that Congress could not have 
intended that each and every SIP submission, regardless of the purpose 
of the submission or the NAAQS in question, would meet each of the 
requirements, or meet each of them in the same way. EPA elected to use 
guidance to make recommendations for infrastructure SIPs for these 
NAAQS.
    On October 2, 2007, EPA issued guidance making recommendations for 
the infrastructure SIP submissions for both the 1997 8-hour ozone NAAQS 
and the 1997 PM2.5 NAAQS.\11\ Within this guidance document, EPA 
described the duty of states to make these submissions to meet what the 
Agency characterized as the ``infrastructure'' elements for SIPs, which 
it further described as the ``basic SIP requirements, including 
emissions inventories, monitoring, and modeling to assure attainment 
and maintenance of the standards.'' \12\ As further identification of 
these basic structural SIP requirements, ``attachment A'' to the 
guidance document included a short description of the various elements 
of section 110(a)(2) and additional information about the types of 
issues that EPA considered germane in the context of such 
infrastructure SIPs. EPA emphasized that the description of the basic 
requirements listed on attachment A was not intended ``to constitute an 
interpretation of'' the requirements, and was merely a ``brief 
description of the required elements.'' \13\ EPA also stated its belief 
that with one exception, these requirements were ``relatively self 
explanatory, and past experience with SIPs for other NAAQS should 
enable States to meet these requirements with assistance from EPA 
Regions.'' \14\ For the one exception to that general assumption--how 
states should proceed with respect to the requirements of section 
110(a)(2)(G) for the 1997 PM2.5 NAAQS--EPA gave much more 
specific recommendations. But for other infrastructure SIP submittals, 
and for certain elements of the submittals for the 1997 
PM2.5 NAAQS, EPA assumed that each State would work with its 
corresponding EPA regional office to refine the scope of a State's 
submittal based on an assessment of how the requirements of section 
110(a)(2) should reasonably apply to the basic structure of the State's 
SIP for the NAAQS in question.
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    \11\ See, ``Guidance on SIP Elements Required Under Section 
110(a)(1) and (2) for the 1997 8-hour Ozone and PM2.5 
National Ambient Air Quality Standards,'' from William T. Harnett, 
Director Air Quality Policy Division, to Air Division Directors, 
Regions I-X, dated October 2, 2007 (the ``2007 Guidance''). EPA 
issued comparable guidance for the 2006 PM2.5 NAAQS 
entitled ``Guidance on SIP Elements Required Under Sections 
110(a)(1) and (2) for the 2006 24-Hour Fine Particle 
(PM2.5) National Ambient Air Quality Standards (NAAQS),'' 
from William T, Harnett, Director Air Quality Policy Division, to 
Regional Air Division Directors, Regions I-X, dated September 25, 
2009 (the ``2009 Guidance'').
    \12\ 2007 Guidance at page 2.
    \13\ Id., at attachment A, page 1.
    \14\ Id., at page 4. In retrospect, the concerns raised by the 
Commenters with respect to EPA's approach to some substantive issues 
indicates that the statute is not so ``self explanatory,'' and 
indeed is sufficiently ambiguous that EPA needs to interpret it in 
order to explain why these substantive issues do not need to be 
addressed in the context of infrastructure SIPs and may be addressed 
at other times and by other means.
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    Significantly, the 2007 Guidance did not explicitly refer to the 
SSM, director's discretion, minor source NSR, or NSR Reform issues as 
among specific substantive issues EPA expected states to address in the 
context of the infrastructure SIPs, nor did EPA give any more specific 
recommendations with respect to how states might address such issues 
even if they elected to do so. The SSM and director's discretion issues 
implicate section 110(a)(2)(A), and the minor source NSR and NSR Reform 
issues implicate section 110(a)(2)(C). In the 2007 Guidance, however, 
EPA did not indicate to states that it intended to interpret these 
provisions as requiring a substantive submission to address these 
specific issues in the context of the infrastructure SIPs for these 
NAAQS. Instead, EPA's 2007 Guidance merely indicated its belief a 
state's submission should establish that the state has the basic SIP 
structure necessary to implement, maintain, and enforce the NAAQS. EPA 
believes that states can establish that they have the basic SIP 
structure, notwithstanding that there may be potential deficiencies 
within the existing SIP. Thus, EPA's proposals mentioned these issues 
not because the Agency considers them issues that must be addressed in 
the context of an infrastructure SIP as required by section 110(a)(1) 
and (2), but rather because EPA wanted to be clear that it considers 
these potential existing SIP problems as separate from the pending 
infrastructure SIP actions.
    EPA believes that this approach to the infrastructure SIP 
requirement is reasonable, because it would not be feasible to read 
sections 110(a)(1) and (2) to require a top to bottom, stem to stern, 
review of each and every provision of an existing SIP for purposes of 
assuring that the State in question has the basic structural elements 
for a functioning SIP for a new or revised NAAQS. Because SIPs have 
grown by accretion over the decades as statutory and regulatory 
requirements under the CAA have evolved, they may include some outmoded 
provisions and historical artifacts that, while not fully up to date, 
nevertheless may not pose a significant problem for the purposes of 
``implementation, maintenance, and enforcement'' of a new or revised 
NAAQS when EPA considers the overall effectiveness of the SIP. To the 
contrary, EPA believes that a better approach is for EPA to determine 
which specific SIP elements from section 110(a)(2) are applicable to an 
infrastructure SIP for a given NAAQS, and to focus attention on those 
elements that are most likely to need a specific SIP revision in light 
of the new or revised NAAQS. Thus, for example, EPA's 2007 Guidance 
specifically directed states to focus on the requirements of section 
110(a)(2)(G) for the 1997 PM2.5 NAAQS because of the absence 
of underlying EPA regulations for emergency episodes for this NAAQS and 
an anticipated absence of relevant provisions in existing SIPs.
    Finally, EPA believes that its approach is a reasonable reading of 
sections 110(a)(1) and (2) because the statute provides other avenues 
and mechanisms to address specific substantive deficiencies in existing 
SIPs. These other statutory tools allow the

[[Page 41127]]

Agency to take appropriate tailored action, depending upon the nature 
and severity of the alleged SIP deficiency. Section 110(k)(5) 
authorizes EPA to issue a ``SIP call'' whenever the Agency determines 
that a state's SIP is substantially inadequate to attain or maintain 
the NAAQS, to mitigate interstate transport, or otherwise to comply 
with the CAA.\15\ Section 110(k)(6) authorizes EPA to correct errors in 
past actions, such as past approvals of SIP submissions.\16\ 
Significantly, EPA's determination that an action on the infrastructure 
SIP is not the appropriate time and place to address all potential 
existing SIP problems does not preclude the Agency's subsequent 
reliance on provisions in section 110(a)(2) as part of the basis for 
action at a later time. For example, although it may not be appropriate 
to require a state to eliminate all existing inappropriate director's 
discretion provisions in the course of acting on the infrastructure 
SIP, EPA believes that section 110(a)(2)(A) may be among the statutory 
bases that the Agency cites in the course of addressing the issue in a 
subsequent action.\17\
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    \15\ EPA has recently issued a SIP call to rectify a specific 
SIP deficiency related to the SSM issue. See ``Finding of 
Substantial Inadequacy of Implementation Plan; Call for Utah State 
Implementation Plan Revision,'' 74 FR 21639 (April 18, 2011).
    \16\ EPA has recently utilized this authority to correct errors 
in past actions on SIP submissions related to PSD programs. See, 
``Limitation of Approval of Prevention of Significant Deterioration 
Provisions Concerning Greenhouse Gas Emitting-Sources in State 
Implementation Plans; Final Rule,'' 75 FR 82536 (December 30, 2010). 
EPA has previously used its authority under CAA 110(k)(6) to remove 
numerous other SIP provisions that the Agency determined it had 
approved in error. See, e.g., 61 FR 38664 (July 25, 1996) and 62 FR 
34641 (June 27, 1997) (corrections to American Samoa, Arizona, 
California, Hawaii, and Nevada SIPs); 69 FR 67062 (November 16, 
2004) (corrections to California SIP); and 74 FR 57051 (November 3, 
2009) (corrections to Arizona and Nevada SIPs).
    \17\ EPA has recently disapproved a SIP submission from Colorado 
on the grounds that it would have included a director's discretion 
provision inconsistent with CAA requirements, including section 
110(a)(2)(A). See, e.g., 75 FR 42342 at 42344 (July 21, 2010) 
(proposed disapproval of director's discretion provisions); 76 FR 
4540 (January 26, 2011) (final disapproval of such provisions).
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III. This Action

    EPA is taking final action to approve Mississippi's infrastructure 
submission as demonstrating that the State meets the applicable 
requirements of sections 110(a)(1) and (2) of the CAA for the 1997 8-
hour ozone NAAQS. Section 110(a) of the CAA requires that each state 
adopt and submit a SIP for the implementation, maintenance, and 
enforcement of each NAAQS promulgated by the EPA, which is commonly 
referred to as an ``infrastructure'' SIP. Mississippi, through MDEQ, 
certified that the Mississippi SIP contains provisions that ensure the 
1997 8-hour ozone NAAQS is implemented, enforced, and maintained in 
Mississippi.
    Mississippi's infrastructure submission, provided to EPA on 
December 7, 2007, addressed all the required infrastructure elements 
for the 1997 8-hour ozone NAAQS. EPA has determined that Mississippi's 
December 7, 2007, infrastructure submission is consistent with section 
110 of the CAA. Additionally, EPA is responding to adverse comments 
received on EPA's March 17, 2011, proposed approval of Mississippi's 
December 7, 2007, infrastructure submission. The responses to comments 
are found in Section IV below.

IV. EPA's Response to Comments

    EPA received one set of comments on the March 17, 2011, proposed 
rulemaking to approve Mississippi's December 7, 2007, infrastructure 
submission as meeting the requirements of sections 110(a)(1) and (2) of 
the CAA for the 1997 8-hour ozone NAAQS. Generally, the Commenter's 
concerns relate to whether EPA's approval of Mississippi's December 7, 
2007, infrastructure submission is in compliance with section 110(l) of 
the CAA, and whether EPA's approval will interfere with the State's 
compliance with the CAA's prevention of significant deterioration (PSD) 
requirements. A full set of the comments provided on behalf of the 
Kentucky Environmental Foundation (hereinafter referred to as ``the 
Commenter'') is provided in the docket for today's final action. A 
summary of the comments and EPA's responses are provided below.
    Comment 1: Under the header ``No Clean Air Act Section 110(l) 
analysis,'' the Commenter states, ``Before providing the technical 
analysis for why finalizing this proposed rule would be contrary to the 
Clean Air Act, I wish to point out that it is 2011 and EPA has yet to 
ensure that these areas have plans to meet the 1997 National Ambient 
Air Quality Standard (NAAQS) for ozone.'' The Commenter goes on to 
state that ``EPA acknowledged that the science indicates that the 1997 
NAAQS, which is effectively 85 parts per billion (ppb), does not 
protect people's health or welfare when in 2008, EPA set a new ozone 
NAAQS at 75 ppb.''
    Response 1: As noted in EPA's proposed rulemaking on Mississippi's 
December 7, 2007, infrastructure submission and in today's final 
rulemaking, the very action that EPA is undertaking is a determination 
that Mississippi has a plan to ensure compliance with the 1997 8-hour 
ozone NAAQS. Mississippi's submission was provided on December 7, 2007, 
for the 1997 8-hour ozone NAAQS, thus the State's submission predates 
the release of the revision to the 8-hour ozone NAAQS on March 12, 
2008, and is distinct from any plan that Mississippi would have to 
provide to ensure compliance of the 2008 NAAQS. This action is meant to 
address, and EPA is approving, the 1997 ozone infrastructure 
requirements under section 110 of the Act. In today's action EPA is not 
addressing the 110 infrastructure requirements for the 2008 ozone NAAQS 
as they will be addressed in a separate rulemaking.
    EPA notes that the 1997 8-hour ozone standard as published in a 
July 18, 1997, final rulemaking notice (62 FR 38856) and effective 
September 18, 1997, are 0.08 parts per million (ppm), which is 
effectively 0.084 ppm or 84 ppb due to the rounding convention and not 
``effectively 85 parts per billion (ppb)'' as the Commenter stated. 
Further, EPA agrees that the Agency has made the determination that the 
1997 8-hour ozone NAAQS is not as protective as needed for public 
health and welfare, and as the Commenter mentioned, the Agency 
established a new ozone NAAQS at 75 ppb. However, the Agency is 
currently reconsidering the 2008 8-hour ozone NAAQS, and has not yet 
designated areas for any subsequent NAAQS.
    Finally, while it is not clear which areas the Commenter refers to 
in stating ``EPA has yet to ensure these areas have plans to meet'' the 
1997 ozone NAAQS, EPA believes this concern is addressed by the 
requirements under section 172, Part D, Title I of the Act for states 
with nonattainment areas for the 1997 ozone NAAQS to submit 
nonattainment plans. As discussed in EPA's notice proposing approval of 
the Mississippi infrastructure SIP, submissions required by section 
110(a)(2)(I) which pertain to the nonattainment planning requirements 
of part D, Title I of the CAA are outside the scope of this action, as 
such plans are not due within three years after promulgation of a new 
or revised NAAQS, but rather are due at the time the nonattainment area 
plan requirements are due pursuant to section 172.\18\
---------------------------------------------------------------------------

    \18\ There were no areas in Mississippi designated nonattainment 
for the 1997 8-hour ozone NAAQS. The entire state was designated 
Unclassifiable/Attainment. Currently, Mississippi has no areas 
violating the 1997 8-hour ozone NAAQS and the State does not contain 
any nonattainment areas for this NAAQS.

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

[[Page 41128]]

    Comment 2: Also under the header ``No Clean Air Act Section 110(l) 
analysis,'' the Commenter cites the section 110(l) CAA requirement, and 
states ``Clean Air Act Sec.  110(l) requires `EPA to evaluate whether 
the plan as revised will achieve the pollution reductions required 
under the Act, and the absence of exacerbation of the existing 
situation does not assure this result.' Hall v. EPA, 273 F.3d 1146, 
1152 (9th Cir. 2001).'' The Commenter goes on to state that ``* * * the 
Federal Register notices are devoid of any analysis of how these rule 
makings will or will not interfere with attaining, making reasonable 
further progress on attaining and maintaining the 75 ppb ozone NAAQS as 
well as the 1-hour 100 ppb nitrogen oxides NAAQS.''
    Response 2: EPA agrees with the Commenter's assertion that 
consideration of section 110(l) of the CAA is necessary for EPA's 
action with regard to approving the State's submission. However, EPA 
disagrees with the Commenter's assertion that EPA did not consider 
110(l) in terms of the March 17, 2011, proposed action. Further, EPA 
disagrees with the Commenter's assertion that EPA's proposed March 17, 
2011, action does not comply with the requirements of section 110(l). 
Section 110(l) provides in part: ``[t]he Administrator shall not 
approve a revision of a plan if the revision would interfere with any 
applicable requirement concerning attainment and reasonable further 
progress * * *, or any other applicable requirement of this chapter.''
    EPA has consistently interpreted section 110(l) as not requiring a 
new attainment demonstration for every SIP submission. The following 
actions are examples of where EPA has addressed 110(l) in previous 
rulemakings: 70 FR 53, 57 (January 3, 2005); 70 FR 17029, 17033 (April 
4, 2005); 70 FR 28429, 28431 (May 18, 2005); and 70 FR 58119, 58134 
(October 5, 2005). Mississippi's December 7, 2007, infrastructure 
submission does not revise or remove any existing emissions limit for 
any NAAQS, or any other existing substantive SIP provisions relevant to 
the 1997 8-hour ozone NAAQS. Simply put, it does not make any 
substantive revision that could result in any change in emissions. As a 
result, the submission does not relax any existing requirements or 
alter the status quo air quality. Therefore, approval of Mississippi's 
December 7, 2007, infrastructure submission will not interfere with 
attainment or maintenance of any NAAQS.
    Comment 3: Under the header ``No Clean Air Act Section 110(l) 
analysis,'' the Commenter states that ``We are not required to guess 
what EPA's Clean Air Act 110(l) analysis would be. Rather, EPA must 
approve in part and disapprove in part these action and re-propose to 
approve the disapproved part with a Clean Air Act Sec.  110(l) 
analysis.'' Further, the Commenter states that ``EPA cannot include its 
analysis in its response to comments and approve the actions without 
providing the public with an opportunity to comment on EPA's Clean Air 
Act Sec.  110(l) analysis.''
    Response 3: Please see Response 2 for a more detailed explanation 
regarding EPA's response to the Commenter's assertion that EPA's action 
is not in compliance with section 110(l) of the CAA. EPA does not agree 
with the Commenter's assertion that EPA's analysis did not consider 
section 110(l) and so therefore ``EPA must approve in part and 
disapprove in part these action and re-propose to approve the 
disapproved part with a Clean Air Act Sec.  110(l) analysis.'' Every 
action that EPA takes to approve a SIP revision is subject to section 
110(l) and thus EPA's consideration of whether a state's submission 
``would interfere with any applicable requirement concerning attainment 
and reasonable further progress * * *, or any other applicable 
requirement of this chapter'' is inherent in EPA's action to approve or 
disapprove a submission from a state. In the ``Proposed Action'' 
section of the March 17, 2011, rulemaking, EPA notes that ``EPA is 
proposing to approve Mississippi's infrastructure submission for the 
1997 8-hour ozone NAAQS because this submission is consistent with 
section 110 of the CAA.'' Section 110(l) is a component of section 110, 
so EPA believes that this provides sufficient notice that EPA 
considered section 110(l) for the proposed action and concluded that 
section 110(l) was not violated.
    Further, EPA does not agree with the Commenter's assertion that the 
Agency cannot provide additional clarification in response to a comment 
concerning section 110(l) and take a final approval action without 
``providing the public with an opportunity to comment on EPA's Clean 
Air Act Sec.  110(l) analysis.'' Clearly such a broad proposition is 
incorrect where the final rule is a logical outgrowth of the proposed 
rule. In fact, the proposition that providing an analysis for the first 
time in response to a comment on a rulemaking per se violates the 
public's opportunity to comment has been rejected by the DC Circuit 
Court of Appeals. See Int'l Harvester Co. v. Ruckelshaus, 478 F.2d 615, 
632 n.51 (DC Cir. 1973).
    Finally, as previously mentioned, EPA's approval of Mississippi's 
December 7, 2007, infrastructure submission does not make any 
substantive revision that could result in any change in emissions, so 
there is no further ``analysis'' beyond whether the state has adequate 
provisions in its SIP to address the infrastructure requirements for 
the 1997 8-hour ozone NAAQS. EPA's March 17, 2011, proposed rulemaking 
goes through each of the relevant infrastructure requirements and 
provides detailed information on how Mississippi's SIP addresses the 
relevant infrastructure requirements. Beyond making a general statement 
indicating that Mississippi's submission is not in compliance with 
section 110(l) of the CAA, the Commenter does not provide comments on 
EPA's detailed analysis of each infrastructure requirement to indicate 
that Mississippi's infrastructure submission for the 1997 8-hour ozone 
NAAQS is deficient in meeting these individual requirements. Therefore, 
the Commenter has not provided a basis to question the Agency's 
determination that Mississippi's December 7, 2007, infrastructure 
submission meets the requirements for the infrastructure submission for 
the 1997 8-hour ozone NAAQS, including section 110(l) of the CAA.
    Comment 4: Under the header ``No Clean Air Act Section 110(l) 
analysis,'' the Commenter further asserts that ``EPA's analysis must 
conclude that this proposed action would [violate] Sec.  110(l) if 
finalized.'' An example given by the Commenter is as follows: ``For 
example, a 42 U.S.C. 7502(a)(2)(J) public notification program based on 
a 85 [parts per billion (ppb)] ozone level interferes with a public 
notification program that should exist for a 75 ppb ozone level. At its 
worst, the public notification system would be notifying people that 
the air is safe when in reality, based on the latest science, the air 
is not safe. Thus, EPA would be condoning the states providing 
information that can physical[ly] hurt people.''
    Response 4: EPA disagrees with the Commenter's statement that EPA's 
analysis must conclude that this proposed action would be in violation 
of section 110(l) if finalized. As mentioned above, Mississippi's 
December 7, 2007, infrastructure submission does not revise or remove 
any existing emissions limit for any NAAQS, nor does it make any 
substantive revision that could result in

[[Page 41129]]

any change in emissions. EPA has concluded that Mississippi's December 
7, 2007, infrastructure submission does not relax any existing 
requirements or alter the status quo air quality. Therefore, approval 
of Mississippi's December 7, 2007, infrastructure submission will not 
interfere with attainment or maintenance of any NAAQS. See Response 2 
and Response 3 above for a more detailed discussion.
    EPA also disagrees with the specific example provided by the 
Commenter that the section 110(a)(2)(J) requirement for public 
notification for the 1997 8-hour ozone NAAQS based on 85 ppb interferes 
with a public notification program that should exist for a 75 ppb ozone 
level, and ``EPA would be condoning the states providing information 
that can physical[ly] hurt people.'' As noted in Response 1, 
Mississippi's December 7, 2007, infrastructure submission was provided 
to address the 1997 8-hour ozone NAAQS and was submitted prior to EPA's 
promulgation of the 2008 8-hour ozone in March 2008. Thus, Mississippi 
provided sufficient information at that time to meet the requirement 
for the 1997 8-hour ozone NAAQS which is the subject of this action.
    Finally, EPA notes that members of the public do get information 
related to the more recent NAAQS via the Air Quality Index (AQI) for 
ozone. When EPA promulgated the 2008 NAAQS, (73 FR 16436, March 27, 
2008) EPA revised the AQI for ozone to show that at the level of the 
2008 ozone NAAQS the AQI is set to 100, which indicates unhealthful 
ozone levels. It is this revised AQI that EPA uses to both forecast 
ozone levels and to provide notice to the public of current air 
quality. The EPA AIRNOW system uses the revised AQI as its basis for 
ozone. In addition, when Mississippi forecasts ozone and provides real-
time ozone information to the public, either through the AIRNOW system 
or through its own Internet based system, the State uses the revised 
ozone AQI keyed to the 2008 revised ozone NAAQS. EPA believes this 
should address the Commenter's legitimate assertion.
    Comment 5: Under the header ``No Clean Air Act Section 110(l) 
analysis,'' the Commenter asserts that ``if a SIP provides an ozone 
NAAQS of 85 ppb for PSD purposes, this interferes with the requirement 
that PSD programs require sources to demonstrate that they will not 
cause or contribute to a violation of a NAAQS because this requirement 
includes the current 75 ppb ozone NAAQS.''
    Response 5: EPA believes that this comment gives no basis for 
concluding that approval of the Mississippi infrastructure SIP violates 
the requirements of section 110(l). EPA assumes that the comment refers 
to the requirement that owners and operators of sources subject to PSD 
demonstrate that the allowable emissions from the proposed source or 
emission increases from a proposed modification, in conjunction with 
all other applicable emissions increases or reductions (including 
secondary emissions) will not cause or contribute to a violation of any 
NAAQS. 40 CFR 51.166(k)(1).
    EPA further assumes that the Commenter's statement ``if a SIP 
provides an ozone NAAQS of 85 ppb for PSD purposes'' refers to a 
hypothetical SIP-approved PSD program that only requires owners and 
operators of sources subject to PSD to make the demonstration discussed 
above for the 1997 ozone NAAQS, and not for the 2008 ozone NAAQS. 
However, the Commenter gives no indication that Mississippi's SIP-
approved PSD program suffers from this alleged defect. EPA has examined 
the relevant provision in Mississippi's SIP, Regulation APC-S-5--
Regulations for the Prevention of Significant Deterioration for Air 
Quality, and has determined that it satisfies the requirements of 
51.166(k)(1) as the State has incorporated by reference 51.166 in its 
entirety.
    Furthermore, as discussed in detail above, the infrastructure SIP 
makes no substantive change to any provision of Mississippi's SIP-
approved PSD program, and therefore does not violate the requirements 
of section 110(l). Had Mississippi submitted a SIP revision that 
substantively modified its PSD program to limit the required 
demonstration to just the 1997 ozone NAAQS, then the comment might have 
been relevant to a 110(l) analysis of that hypothetical SIP revision. 
However, in this case, the comment gives no basis for EPA to conclude 
that the Mississippi infrastructure SIP would interfere with any 
applicable requirement of the Act.
    EPA concludes that approval of Mississippi's December 7, 2007, 
infrastructure submission will not make the status quo air quality 
worse and is in fact consistent with the development of an overall plan 
capable of meeting the Act's requirements. Accordingly, when applying 
section 110(l) to this submission, EPA finds that approval of 
Mississippi's December 7, 2007, infrastructure submission is consistent 
with section 110 (including section 110(l)) of the CAA.
    Comment 6: The Commenter provided comments on opposing the proposed 
approval of the infrastructure submission because it did not identify a 
specific model to be used to demonstrate that a PSD source will not 
cause or contribute to a violation of the ozone NAAQS. Specifically, 
the commenter stated: ``[t]he SIP submittals do not comply with Clean 
Air Act 110(a)(2)(J), (K), and (D)(i)(II) because the SIP submittals do 
not identify a specific model to use in PSD permitting to demonstrate 
that a proposed source of modification will not cause or contribute to 
a violation [or] the ozone NAAQS.''
    The commenter asserted that because EPA does not require the use of 
a specific model, states use no modeling or use deficient modeling to 
evaluate these impacts. Specifically, the commenter alleged: ``Many 
states abuse this lack of an explicitly named model by claiming that 
because no model is explicitly named, no modeling is required or use of 
completely irrelevant modeling (e.g. Kentucky using modeling from 
Georgia for the J.K. Smith proposed facility) is allowed.''
    To support the argument that EPA should designate a particular 
model and require states to use it, the Commenter attached and 
incorporated by reference a prior petition for rulemaking requesting 
that EPA designate such a model.\19\ The petition in question was 
submitted by Robert Ukeiley on behalf of the Sierra Club on July 28, 
2010, requesting EPA to designate air quality models to use for PSD 
permit applications with regard to ozone and PM2.5. As 
supporting documentation for that petition for rulemaking, the 
Commenter also resubmitted 15 attachments in the comment on EPA's 
proposed approval of the infrastructure submission. These attachments 
were as follows:
---------------------------------------------------------------------------

    \19\ The Commenter attached the July 28, 2010, ``Petition for 
Rulemaking to Designate Air Quality Models to use for PSD Permit 
Applications with Regard to Ozone and PM2.5,'' from 
Robert Ukeiley on behalf of the Sierra Club.

    1. Exhibit 1: Comments from Camille Sears on the Ninth 
Conference on Air Quality Modeling (Docket ID: EPA-HQ-OAR-2008-0604) 
(November 10, 2008);
    2. Exhibit 2: ``Response to Petitions for Review, Supplemental 
Briefs, and Amicus Brief'' regarding the Desert Rock Energy Company, 
LLC from Ann Lyons, EPA Region 9--Office of Regional Counsel and 
Brian L. Doster/Elliot Zenick, EPA Headquarters--Office of General 
Counsel (January 8, 2009);
    3. Exhibit 3: Report, The Kentucky Natural Resources and 
Environmental Protection Cabinet, A Cumulative Assessment of the 
Environmental Impacts Caused by Kentucky Electric Generating Units, 
(December 17, 2001);
    4. Exhibit 4: Letter from Richard A. Wayland, Director of the 
Air Quality

[[Page 41130]]

Assessment Division, EPA Office Air Quality and Planning Standards 
to Robert Ukeiley regarding Mr. Ukeiley's Freedom of Information Act 
(FOIA) request on behalf of the Sierra Club for documents related to 
EPA development of a modeling protocol for PM2.5 (October 
1, 2008);
    5. Exhibit 5: Expert Report of Lyle R. Chinkin and Neil J. M. 
Wheeler, Analysis of Air Quality Impacts, prepared for Civil Action 
No. IP99-1693 C-M/S United States v. Cinergy Corp., (August 28, 
2008);
    6. Exhibit 6: Illinois Environmental Protection Agency, Bureau 
of Air, Assessing the impact on the St. Louis Ozone Attainment 
Demonstration from the proposed electrical generating units in 
Illinois'' (September 25, 2003);
    7. Exhibit 7: Memorandum from Stephen D. Page, Director, EPA 
Office Air Quality and Planning Standards entitled, ``Modeling 
Procedures for Demonstrating Compliance with the PM2.5 
NAAQS'' (March 23, 2010);
    8. Exhibit 8: E-mail from Scott B. (Title and Affiliation not 
provided), to Donna Lucchese, (Title and Affiliation not provided), 
entitled, ``Ozone impact of point source'' (Date described as 
``Early 2000'');
    9. Exhibit 9: E-mail from Mary Portanova, EPA, Region 5, to 
Noreen Weimer, EPA, Region 5, entitled ``FOIA--Robert Ukeiley--RIN-
02114-09'' (October 20, 2009, 10:05 CST);
    10. Exhibit 10: Synopsis from PSD Modeling Workgroup--EPA/State/
Local Workshop, New Orleans (May 17, 2005);
    11. Exhibit 11: Letter from Carl E. Edlund, P.E., Director, EPA, 
Region 6 Multimedia Planning and Permitting Division to Richard 
Hyde, P.E. Deputy Director of the Office of Permitting and 
Registration, Texas Commission on Environmental Quality regarding 
``White Stallion Energy Center, PSD Permit Nos. PSD-TX-1160, PAL 26, 
and HAP 28'' (February 10, 2010);
    12. Exhibit 12: Memorandum from John S. Seitz, Director, EPA 
Office of Air Quality Planning & Standards entitled, ``Interim 
Implementation of New Source Review Requirements for 
PM2.5'' (October 23, 1997);
    13. Exhibit 13: Presentation by Erik Snyder and Bret Anderson 
(Titles and Affiliations not provided), to R/S/L Workshop, Single 
Source Ozone/PM2.5 Impacts in Regional Scale Modeling & 
Alternate Methods, (May 18, 2005);
    14. Exhibit 14: Letter from Richard D. Scheffe, PhD, Senior 
Science Advisor, EPA, Office of Air Quality Planning & Standards to 
Abigail Dillen in response to an inquiry regarding the applicability 
of the Scheffe Point Source Screening Tables (July 28, 2000);
    15. Exhibit 15: Presentation by Gail Tonnesen, Zion Wang, 
Mohammad Omary, Chao-Jung Chien (University of California, 
Riverside); Zac Adelman (University of North Carolina); Ralph Morris 
et al. (ENVIRON Corporation Int., Novato, CA) to the Ozone MPE, TAF 
Meeting, Review of Ozone Performance in WRAP Modeling and Relevance 
to Future Regional Ozone Planning, (July 30, 2008).

    Finally, the Commenter stated that ``EPA has issued guidance 
suggesting [that] PSD sources should use the ozone limiting method for 
NOX modeling.'' The Commenter referred to EPA's March 2011 
NOX modeling guidance to support this position.\20\ The 
Commenter then asserts that this ``ozone modeling'' helps sources 
demonstrate compliance and that sources should also do ozone modeling 
that may inhibit a source's permission to pollute. The Commenter argued 
that EPA's guidance supports the view that EPA must require states to 
require a specific model in their SIPs to demonstrate that proposed PSD 
sources do not cause or contribute to a violation of the ozone NAAQS.
---------------------------------------------------------------------------

    \20\ The Commenter attached an EPA memorandum dated March 1, 
2011: ``Additional Clarification Regarding Application of Appendix W 
Modeling Guidance for the 1-hour NO2 National Ambient Air 
Quality Standard,'' from Tyler Fox, Leader, Air Quality Modeling 
Group, Office of Air Quality Planning and Standards.
---------------------------------------------------------------------------

    Response 6: EPA disagrees with the Commenter's views concerning 
modeling in the context of acting upon the infrastructure submission. 
The Commenter raised four primary interrelated arguments: (1) The 
state's infrastructure SIP must specify a required model; (2) the 
failure to specify a model leads to inadequate analysis; (3) the 
attached petition for rulemaking explains why EPA should require states 
to specify a model; and (4) a recent guidance document concerning 
modeling for NOX sources recommends using ozone limit 
methods for NOX sources and EPA could issue comparable 
guidance for modeling ozone from a single source.
    At the outset, EPA notes that although the Commenter sought to 
incorporate by reference the prior petition for rulemaking requesting 
EPA to designate a particular model for use by states for this purpose, 
the Agency is not required to respond to that petition in the context 
of acting upon the infrastructure submission. In reviewing the 
infrastructure submission, EPA is evaluating the state's submission in 
light of current statutory and regulatory requirements, not in light of 
potential future requirements that EPA has been requested to establish 
in a petition. Moreover, the petition arose in a different context, 
requests different relief, and raises other issues unrelated to those 
concerning ozone modeling raised by the Commenter in this action. EPA 
believes that the appropriate place to respond to the issues raised in 
the petition is in a petition response. Accordingly, EPA is not 
responding to the July 28, 2010 petition, in this action. The issues 
raised in that petition are under separate consideration.
    EPA believes that the comment concerning the approvability of the 
infrastructure submission based upon whether the SIP specifies the use 
of a particular model are germane to this action, but EPA disagrees 
with the Commenter's conclusions. The Commenter stated that the SIP 
submittals ``do not comply with Clean Air Act 110(a)(2)(J), (K), and 
(D)(i)(II) because the SIP submittals do not identify a specific model 
to use in PSD permitting to demonstrate that a proposed source [or] 
modification will not cause or contribute to a violation of the ozone 
NAAQS.'' EPA's PSD permitting regulations are found at 40 CFR 51.166 
and 52.21. PSD requirements for SIPs are found in 40 CFR 51.166. 
Similar PSD requirements for SIPs that have been disapproved with 
respect to PSD and for SIPs incorporating EPA's regulations by 
reference are found in 40 CFR 52.21. The PSD regulations require an 
ambient impact analysis for ozone for proposed major stationary sources 
and major modifications to obtain a PSD permit (40 CFR 
51.166(b)(23)(i), (i)(5)(i)(f),\21\ (k), (l) and (m) and 40 CFR 
52.21(b)(23)(i), (i)(5)(i)(f),\22\ (k), (l) and (m)). The regulations 
at 40 CFR 51.166(l) state that for air quality models the SIP shall 
provide for procedures which specify that:
---------------------------------------------------------------------------

    \21\ Citation includes a footnote: ``No de minimis air quality 
level is provided for ozone. However, any net emissions increase of 
100 tons per year or more of volatile organic compounds or nitrogen 
oxides subject to PSD would be required to perform an ambient impact 
analysis, including the gathering of ambient air quality data.''
    \22\ Id.
---------------------------------------------------------------------------

    (1) All applications of air quality modeling involved in this 
subpart shall be based on the applicable models, data bases, and other 
requirements specified in Appendix W of this part (Guideline on Air 
Quality Models).
    (2) Where an air quality model specified in Appendix W of this part 
(Guideline on Air Quality Models) is inappropriate, the model may be 
modified or another model substituted. Such a modification or 
substitution of a model may be made on a case-by-case basis or, where 
appropriate, on a generic basis for a specific State program. Written 
approval of the Administrator must be obtained for any modification or 
substitution. In addition, use of a modified or substituted model must 
be subject to notice and opportunity for public comment under 
procedures set forth in Sec.  51.102.
    These parts of 40 CFR Part 51 and 52 are the umbrella SIP 
components that states have either adopted by reference or the states 
have approved or been delegated authority to incorporate the PSD 
requirements of the CAA. As

[[Page 41131]]

discussed above, these CFR part 51 and 52 PSD requirements refer to 40 
CFR Part 51, Appendix W for the appropriate model to utilize for the 
ambient impact assessment. 40 CFR Part 51, Appendix W is the Guideline 
on Air Quality models and Section 1.0.a. states:

    The Guideline recommends air quality modeling techniques that 
should be applied to State Implementation Plan (SIP) revisions for 
existing sources and to new source review (NSR), including 
prevention of significant deterioration (PSD) [footnotes not 
included]. Applicable only to criteria air pollutants, it is 
intended for use by EPA Regional Offices in judging the adequacy of 
modeling analyses performed by EPA, State and local agencies, and by 
industry * * * The Guideline is not intended to be a compendium of 
modeling techniques. Rather, it should serve as a common measure of 
acceptable technical analysis when supported by sound scientific 
judgment.
    Appendix W Section 5.2.1. includes the Guideline recommendations 
for models to be utilized in assessing ambient air quality impacts 
for ozone. Specifically, Section 5.2.1.c states: ``Estimating the 
Impact of Individual Sources. Choice of methods used to assess the 
impact of an individual source depends on the nature of the source 
and its emissions. Thus, model users should consult with the 
Regional Office to determine the most suitable approach on a case-
by-case basis (subsection 3.2.2).''

    Appendix W Section 5.2.1.c provides that the model users (state and 
local permitting authorities and permitting applicants) should work 
with the appropriate EPA Regional Office on a case-by-case basis to 
determine an adequate method for performing an air quality analysis for 
assessing ozone impacts. Due to the complexity of modeling ozone and 
the dependency on the regional characteristics of atmospheric 
conditions, EPA believes this is an appropriate approach rather than 
specifying one particular preferred model nationwide, which may not be 
appropriate in all circumstances. Instead, the choice of method 
``depends on the nature of the source and its emissions. Thus, model 
users should consult with the Regional Office * * * .'' Appendix W 
Section 5.2.1.c. Therefore, EPA continues to believe it is appropriate 
for permitting authorities to consult and work with EPA Regional 
Offices as described in Appendix W, including section 3.0.b and c, 
3.2.2, and 3.3, to determine the appropriate approach to assess ozone 
impacts for each PSD required evaluation.23 24 25 26 
Although EPA has not selected one particular preferred model in 
Appendix A of Appendix W (Summaries of Preferred Air Quality Models) 
for conducting ozone impact analyses for individual sources, state/
local permitting authorities must comply with the appropriate PSD FIP 
or SIP requirements with respect to ozone.
---------------------------------------------------------------------------

    \23\ 40 CFR part 51 Appendix W, Section 3.0.b. states: ``In this 
guidance, when approval is required for a particular modeling 
technique or analytical procedure, we often refer to the 
`appropriate reviewing authority'. In some EPA regions, authority 
for NSR and PSD permitting and related activities have been 
delegated to State and even local agencies. In these cases, such 
agencies are `representatives' of the respective regions. Even in 
these circumstances, the Regional Office retains authority in 
decisions and approvals. Therefore, as discussed above and depending 
on the circumstances, the appropriate reviewing authority may be the 
Regional Office, Federal Land Manager(s), State agency(ies), or 
perhaps local agency(ies). In cases where review and approval comes 
solely from the Regional Office (sometimes stated as `Regional 
Administrator'), this will be stipulated. If there is any question 
as to the appropriate reviewing authority, you should contact the 
Regional modeling contact (http://www.epa.gov/scram001/tt28.htm#regionalmodelingcontacts) in the appropriate EPA Regional 
Office, whose jurisdiction generally includes the physical location 
of the source in question and its expected impacts.''
    \24\ 40 CFR part 51 Appendix W, Section 3.0.c. states: ``In all 
regulatory analyses, especially if other-than-preferred models are 
selected for use, early discussions among Regional Office staff, 
State and local control agencies, industry representatives, and 
where appropriate, the Federal Land Manager, are invaluable and 
encouraged. Agreement on the data base(s) to be used, modeling 
techniques to be applied and the overall technical approach, prior 
to the actual analyses, helps avoid misunderstandings concerning the 
final results and may reduce the later need for additional analyses. 
The use of an air quality analysis checklist, such as is posted on 
EPA's Internet SCRAM Web site (subsection 2.3), and the preparation 
of a written protocol help to keep misunderstandings at a minimum.''
    \25\ 40 CFR part 51 Appendix W, Section 3.2.2.a. states: 
``Determination of acceptability of a model is a Regional Office 
responsibility. Where the Regional Administrator finds that an 
alternative model is more appropriate than a preferred model, that 
model may be used subject to the recommendations of this subsection. 
This finding will normally result from a determination that (1) a 
preferred air quality model is not appropriate for the particular 
application; or (2) a more appropriate model or analytical procedure 
is available and applicable.''
    \26\ 40 CFR part 51 Appendix W, Section 3.3.a. states: ``The 
Regional Administrator has the authority to select models that are 
appropriate for use in a given situation. However, there is a need 
for assistance and guidance in the selection process so that 
fairness and consistency in modeling decisions is fostered among the 
various Regional Offices and the States. To satisfy that need, EPA 
established the Model Clearinghouse and also holds periodic 
workshops with headquarters, Regional Office, State, and local 
agency modeling representatives.'' Section 3.3.b. states ``The 
Regional Office should always be consulted for information and 
guidance concerning modeling methods and interpretations of modeling 
guidance, and to ensure that the air quality model user has 
available the latest most up-to-date policy and procedures. As 
appropriate, the Regional Office may request assistance from the 
Model Clearinghouse after an initial evaluation and decision has 
been reached concerning the application of a model, analytical 
technique or data base in a particular regulatory action.'' 
(footnote omitted).
---------------------------------------------------------------------------

    The current SIP meets the requirements of 40 CFR 52.21 and 40 CFR 
51.166(l)(1). Specifically, the Mississippi SIP states at Regulation 
APC-S-2 (V) (B)--Air Quality Models:

    ``1. All estimates of ambient concentrations of air pollutants 
shall be based on the applicable air quality models, data bases, and 
other requirements specified in the ``Guideline on Air Quality 
Models (Revised)'' 40 CFR, Part 52,\27\ Appendix W, which are 
incorporated herein and adopted by reference.
---------------------------------------------------------------------------

    \27\ This reference to part 52 is a typographical error and 
should reference part 51.
---------------------------------------------------------------------------

    2. Where an air quality impact model specified in the 
``Guideline on Air Quality Models (Revised)'' 40 CFR, Part 52,\28\ 
Appendix W, is inappropriate, the model may be modified or another 
model substituted. Such a modification or substitution of a model 
may be made on a case-by-case basis or, where appropriate, on a 
generic basis. Written approval of the DEQ and the Administrator of 
EPA must be obtained for any modification or substitution. In 
addition, use of a modified or substituted model shall be subject to 
public notice and opportunity for public comment.''
---------------------------------------------------------------------------

    \28\ This reference to part 52 is a typographical error and 
should reference part 51.

---------------------------------------------------------------------------
    Additionally, the Mississippi SIP states at Regulation APC-S-5(1):

    The purpose of this regulation is to implement a program for the 
prevention of significant deterioration of air quality as required 
by 40 CFR 52.21 and 51.166. This regulation supersedes and replaces 
the previous adoption by reference of 40 CFR 52.21 and 40 CFR 
51.166. 40 CFR 52.21 and 51.166 as used in this regulation refer to 
the federal regulations as amended and promulgated by July 1, 2004 * 
* *

    These statements in the Federally approved Mississippi SIP provide 
a reference to 40 CFR Part 51, Appendix W. The commitment in 
Mississippi's SIP to implement and adopt air quality models utilizing 
40 CFR part 51, Appendix W as a basis is appropriate and consistent 
with Federal regulations.
    Mississippi requires that PSD permit applications contain an 
analysis of ozone impacts from the proposed project. As recommended by 
Appendix W, the methods used for the ozone impacts analysis for 
individual PSD permit actions are determined on a case-by-case basis. 
Mississippi consults with EPA Region 4 on a case-by-case basis for 
evaluating the adequacy of the ozone impact analysis. When appropriate, 
EPA Region 4 provides input/comments on the analysis. As stated in 
Section 5.2.1.c. of Appendix W, the ``[c]hoice of methods used to 
assess the impact of an individual source depends on the nature of the 
source and its emissions.'' Therefore, based on an evaluation of the 
source, its emissions and background ozone concentrations, an ozone 
impact analysis other than modeling may be required. While in others 
cases a

[[Page 41132]]

complex photochemical grid type modeling analysis, as discussed below, 
may be warranted. As noted, the appropriate methods are determined in 
consultation with EPA Region 4 on a case-by-case basis.
    As a second point, the Commenter asserted that states abuse this 
lack of an explicitly named model by claiming that because no model is 
explicitly named, no modeling is required or the use of completely 
irrelevant modeling is allowed.
    EPA agrees that States should not be using inappropriate analytical 
tools in this context. For example, the Commenter's Exhibit 14 does 
discuss the inappropriateness of using a screening technique referred 
to as the ``Scheffe Tables.'' The Commenter is correct that the use of 
``Scheffe Tables'' and other particular screening techniques, which 
involve ratios of nitrogen oxides (NOX) to volatile organic 
compounds (VOC) that do not consider the impact of biogenic emissions, 
or that use other outdated or irrelevant modeling, is inappropriate to 
evaluate a single source's ozone impacts on an air quality control 
region. More scientifically appropriate screening and refined tools are 
available and should be considered for use. Therefore, EPA continues to 
believe States should consult and work with EPA Regional Offices as 
described in Appendix W on a case-by-case basis to determine the 
appropriate method for estimating the impacts of these ozone precursors 
from individual sources.
    For ozone, a proposed emission source's impacts are dependent upon 
local meteorology and pollution levels in the surrounding atmosphere. 
Ozone is formed from chemical reactions in the atmosphere. The impact a 
new or modified source can have on ozone levels is dependent, in part, 
upon the existing atmospheric pollutant loading already in the region 
with which emissions from the new or modified source can react. In 
addition, meteorological parameters such as wind speed, temperature, 
wind direction, solar radiation influx, and atmospheric stability are 
also important factors. The more sophisticated analyses consider 
meteorology and interactions with emissions from surrounding sources. 
EPA has not identified an established modeling system that would fit 
all situations and take into account all of the additional local 
information about sources and meteorological conditions. The Commenter 
submitted a number of exhibits (including Exhibits 10, 11, and 13) in 
which EPA has previously indicated a preference for using a 
photochemical grid model when appropriate modeling databases exist and 
when it is acceptable to use the photochemical grid modeling to assess 
a specific source.
    Commenter's Exhibit 13 includes a list of issues to evaluate, which 
aid in considering if the existing photochemical grid modeling 
databases are acceptable, and discusses the need for permitting 
authorities to consult with the EPA Regional Office in determining if 
photochemical grid modeling would be appropriate for conducting an 
ozone impacts analysis. In these documents EPA has indicated that 
photochemical grid modeling (e.g., CAMx or CMAQ) is generally the most 
sophisticated type of modeling analysis for evaluating ozone impacts, 
and it is usually conducted by adding a source into an existing 
modeling system to determine the change in impact from the source. The 
analysis is done by comparing the photochemical grid modeling results 
which include the new or modified source under evaluation with the 
results from the original modeling analysis that does not contain the 
source. Photochemical grid modeling is often an excellent modeling 
exercise for evaluating a single source's impacts on an air quality 
control region when such models are available and appropriate to 
utilize because they take into account the important parameters and the 
models have been used in regional modeling for attainment SIPs.
    There are also reactive plume models, however, that may also be 
appropriate. EPA has approved the use of plume models in some 
instances, but these models are not always appropriate because of the 
difficulty in obtaining the background information to make an 
appropriate assessment of the photochemistry and meteorology impacts.
    The use of reactive plume models may also be appropriate under 
certain circumstances. EPA has approved the use of plume models in some 
instances, but these models are not always appropriate because of the 
difficulty in obtaining the background information to make an 
appropriate assessment of the photochemistry and meteorology impacts.
    EPA has not selected a specific ``preferred'' model for conducting 
an ozone impact analysis. Model selection normally depends upon the 
details about the modeling systems available and if they are 
appropriate for assessing the impacts from a proposed new source or 
modification. Considering that a photochemical modeling system with 
inputs, including meteorological and emissions data, that would also 
have to be evaluated for model performance, could potentially be costly 
and time consuming to develop, EPA has taken a case-by-case evaluation 
approach. Such photochemical modeling databases are typically developed 
so that impacts of regulatory actions across multiple sources can be 
evaluated, and therefore the time and financial costs can be absorbed 
by the regulatory body. It is these types of databases that have the 
potential to be used to assess single source ozone impacts after they 
have been developed as part of a regional modeling demonstration to 
support a SIP. From a cost and time requirement standpoint, EPA would 
generally not expect a single source to develop an entire photochemical 
modeling system just to evaluate its individual impacts on an air 
quality region, as long as other methods of analyzing ozone impacts are 
available and acceptable to EPA.
    When an existing photochemical modeling system is deemed 
appropriate, it is an excellent tool to evaluate the ozone impact that 
a single source's emissions can have on an air quality region in the 
context of PSD modeling and should be evaluated for potential use. More 
often now than 10 or 15 years ago, a photochemical modeling system may 
be available that covers the geographic area of concern. EPA notes that 
even where photochemical modeling is readily available, it should be 
evaluated as part of the development of a modeling protocol, in 
consultation with the Regional Office to determine its appropriateness 
for conducting an impact analysis for a particular proposed source or 
modification.\29\ Factors to consider when evaluating the 
appropriateness of a particular photochemical modeling system include, 
but are not limited to, meteorology, year of emissions projections, 
model performance issues in the area of concern or in areas that might 
impact projections in the area of concern. Therefore, even where 
photochemical modeling systems exist, there may be circumstances where 
their use is inappropriate for estimating the ozone impacts of a 
proposed source or modification. Because of these scientific issues and 
the need for appropriate case-by-case technical considerations, EPA has 
not designated a single ``Preferred Model'' for conducting single 
source impact analyses for ozone in Appendix A or Appendix W.
---------------------------------------------------------------------------

    \29\ 40 CFR part 51 Appendix W, Sections 3.0, 3.2., 3.3, 5.2.1.c 
and commenter Exhibit 13.
---------------------------------------------------------------------------

    In summary, the Commenter states that many States abuse this lack 
of an explicitly named model by claiming that because no model is 
explicitly named, no modeling is required or use of

[[Page 41133]]

completely irrelevant modeling is allowed. For the reasons described in 
this response to comment, we do not believe that one modeling system is 
presently appropriate to designate for all situations, yet that does 
not relieve proposed sources and modifications from the obligation of 
making the required demonstration under the applicable PSD rules. The 
Mississippi SIP contains a reference for use of the procedures 
specified in EPA's ``Guideline on Air Quality Models'' (40 CFR part 51 
Appendix W) for estimating ambient concentrations of criteria 
pollutants, including ozone (Regulation APC-S-2 (V)(B)--Air Quality 
Models). As such, Mississippi requires that PSD permit applications 
contain an analysis of ozone impacts from the proposed project. As 
recommended by Appendix W, the methods used for the ozone impacts 
analysis are determined on a case-by-case basis. Mississippi consults 
with EPA Region 4 on a case-by-case basis for evaluating the adequacy 
of the ozone impact analysis. When appropriate, EPA Region 4 provides 
input/comments on the analysis. Because EPA has not designated one 
particular model as being appropriate in all situations for evaluating 
single source ozone impacts, EPA Region 4 concurs with Mississippi's 
proposed approach.
    In conclusion, for the reasons stated it is difficult to identify 
and implement a specific standardized national model for ozone. EPA has 
had a standard approach in its PSD SIP and FIP rules of not mandating 
the use of a particular model for all circumstances, instead treating 
the choice of a particular method for analyzing ozone impacts as 
circumstance-dependent. EPA then determines whether the State's 
implementation plan revision submittal meets the PSD SIP requirements. 
For purposes of review for this infrastructure SIP, Mississippi has an 
EPA-approved PSD SIP that meets the EPA PSD requirements under 40 CFR 
51.166.
    Finally, the Commenter argued that EPA's March 2011 guidance 
concerning modeling for the 1-hour nitrogen dioxide (NO2) 
NAAQS demonstrates that similar single source modeling could be 
conducted for sources for purposes of the ozone NAAQS. Specifically, 
the commenter argued that the model used for other criteria pollutants 
(AERMOD), incorporates ozone chemistry for modeling NO2 and 
therefore is modeling ozone chemistry for a single source. The 
Commenter stated that this guidance suggested that PSD sources should 
use the ozone limiting method for NOX modeling.\30\ Further, 
the Commenter noted that this technique ``is modeling of ozone 
chemistry for a single source.'' and therefore that this modeling with 
ozone chemistry allows a source to be permitted. The commenter 
concludes with the assertion that EPA must require the SIPs to include 
a model to use to demonstrate that proposed PSD sources do not cause or 
contribute to a violation of an ozone NAAQS.
---------------------------------------------------------------------------

    \30\ The Commenter attached EPA memorandum dated March 1, 2011: 
``Additional Clarification Regarding Application of Appendix W 
Modeling Guidance for the 1-hour NO2 National Ambient Air 
Quality Standard,'' from Tyler Fox, Leader, Air Quality Modeling 
Group, Office of Air Quality Planning and Standards.
---------------------------------------------------------------------------

    EPA's recent March 2011 guidance for the NO2 NAAQS does 
discuss using two different techniques to estimate the amount of 
conversion of NOX emissions to NO2 ambient 
NO2 concentrations as part of the NO2 modeling 
guidance. NOX emissions are composed of NO and 
NO2 molecules. These two techniques, which have been 
available for years, are the Ozone Limiting Method (OLM), which was 
mentioned by the Commenter, and the Plume Volume Molar-Ratio-Method 
(PVMRM). Both of these techniques are designed and formulated based on 
the principle of assuming available atmospheric ozone mixes with NO/
NO2 emissions from sources. This ``mixing'' results in ozone 
molecules reacting with the NO molecules to form NO2 and 
O2. This is a simple one-direction chemical reaction that is 
used to determine how much NO is converted to NO2 for 
modeling of the NO2 standard. Thus, these techniques do not 
predict ozone concentrations, rather they take ambient ozone data as 
model inputs to determine the calculation of NO conversion to 
NO2. These techniques are not designed to calculate the 
amount of ozone that might be generated as the NOX emissions 
traverses downwind of the source and potentially reacts with other 
pollutants in the atmosphere. Rather, these two techniques rely on a 
one-way calculation based on an ozone molecule (O3) reacting 
with an NO molecule to generate an NO2 molecule and an 
O2 molecule.31 32
---------------------------------------------------------------------------

    \31\ ``AERMOD: Model Formulation Document'', http://www.epa.gov/scram001/7thconf/aermod/aermod_mfd_addm_rev.pdf.
    \32\ Hanrahan, P.L., 1999a. ``The plume volume molar ratio 
method for determining NO2/NOX ratios in 
modeling. Part I: Methodology,'' J. Air & Waste Manage. Assoc., 49, 
1324-1331.
---------------------------------------------------------------------------

    As previously mentioned, these two techniques do not attempt to 
estimate the amount of ozone that might be generated, and the models in 
which these techniques are applied are not designed or formulated to 
even account for the potential generation of ozone from emissions of 
NO/NO2. Ozone chemistry has many cycles of destruction and 
generation and is dependent upon a large number of variables, including 
VOC concentrations and the specific types of VOC molecules present, 
other atmospheric pollutant concentrations, meteorological conditions, 
and solar radiation levels as already discussed in this response. Since 
OLM and PVMRM do not include any of these scientific principles and do 
not account for any chemical mechanisms that would generate ozone, 
these techniques cannot be used for determining potential changes in 
ozone levels from a proposed source or modification.
    In summary, the Commenter asserts that the OLM technique models of 
ozone chemistry for a single source and that this modeling helps a 
source demonstrate compliance with the NO2 standard. The 
Commenter is concerned that EPA has not designated a single specific 
OLM technique is not also used to determine ozone impacts and believes 
that EPA should rectify this concern. To do so the Commenter concludes 
that EPA must require the SIPs to include a model to demonstrate that 
proposed PSD sources do not cause or contribute to a violation of an 
ozone NAAQS. As previously discussed, EPA disagrees and reiterates that 
the OLM (and PVMRM) are simple chemistry techniques that are not 
formulated to be capable to determine potential ozone impacts from a 
proposed source or modification.
    For the reasons discussed above, EPA does not believe that the 
comments provide a basis for not approving the infrastructure 
submission. In short, EPA has not modified the Guidelines in Appendix W 
for ozone impacts analysis for a single source (Appendix W Part 
5.2.1.c.) to require use of a specific model as the Commenter requests. 
EPA finds that the State has the appropriate regulations to operate the 
PSD program consistent with Federal requirements. Furthermore, we 
disagree that states are required to designate a specific model in the 
SIP, because App. W states that state and local agencies should consult 
with EPA on a case-by-case basis to determine what analysis to require.

V. Final Action

    As described above, MDEQ has addressed the elements of the CAA 
110(a)(1) and (2) SIP requirements pursuant to EPA's October 2, 2007, 
guidance to ensure that the 1997 8-hour ozone NAAQS are implemented, 
enforced, and maintained in Mississippi. EPA is taking final action to

[[Page 41134]]

approve Mississippi's December 7, 2007, infrastructure submission for 
the 1997 8-hour ozone NAAQS because this submission is consistent with 
section 110 of the CAA.

VI. Statutory and Executive Order Reviews

    Under the CAA, 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 CAA. 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 CAA; 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 CAA, petitions for judicial review 
of this action must be filed in the United States Court of Appeals for 
the appropriate circuit by September 12, 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, 
Reporting and recordkeeping requirements, Volatile organic compounds.

    Dated: June 30, 2011.
A. Stanley Meiburg,
Acting Regional Administrator, Region 4.

    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 Z--Mississippi

0
2. Section 52.1270(e) is added to read as follows:


Sec.  52.1270  Identification of plan.

* * * * *
    (e) EPA approved Mississippi non-regulatory provisions.

                               EPA Approved Mississippi Non-Regulatory Provisions
----------------------------------------------------------------------------------------------------------------
                                        Applicable           State
    Name of non-regulatory SIP        geographic or     submittal date/  EPA approval date       Explanation
            provision               nonattainment area  effective date
----------------------------------------------------------------------------------------------------------------
110(a)(1) and (2) Infrastructure   Mississippi........       12/7/2007  7/13/2011 [Insert    For the 1997 8-hour
 Requirements for the 1997 8-Hour                                        citation of          ozone NAAQS.
 Ozone National Ambient Air                                              publication].
 Quality Standards.
----------------------------------------------------------------------------------------------------------------



[[Page 41135]]

[FR Doc. 2011-17467 Filed 7-12-11; 8:45 am]
BILLING CODE 6560-50-P