Determination of Attainment, Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality Planning Purposes; Indiana; Redesignation of the Evansville Area To Attainment of the 8-Hour Ozone Standard, 77026-77042 [05-24542]

Agencies

• ENVIRONMENTAL PROTECTION AGENCY

[Federal Register Volume 70, Number 249 (Thursday, December 29, 2005)]
[Rules and Regulations]
[Pages 77026-77042]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-24542]



[[Page 77026]]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R05-OAR-2005-IN-0006; FRL-8015-7]


Determination of Attainment, Approval and Promulgation of 
Implementation Plans and Designation of Areas for Air Quality Planning 
Purposes; Indiana; Redesignation of the Evansville Area To Attainment 
of the 8-Hour Ozone Standard

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

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SUMMARY: EPA is determining that the Evansville 8-hour ozone 
nonattainment area (Evansville area) has attained the 8-hour ozone 
National Ambient Air Quality Standard (NAAQS). The Evansville area 
includes Vanderburgh and Warrick Counties. EPA is approving a request 
from the State of Indiana, submitted on June 2, 2005, to redesignate 
the Evansville area from nonattainment to attainment for the 8-hour 
ozone NAAQS. EPA's approval of the redesignation request is based on 
the determination that the Evansville area and the State of Indiana 
have met the criteria for redesignation to attainment set forth in the 
Clean Air Act (CAA), including the determination that the Evansville 
area has attained the 8-hour ozone standard. In conjunction with this 
approval, EPA is approving the State's plan for maintaining the 8-hour 
ozone NAAQS in the Evansville area through 2015 as a revision to the 
Indiana State Implementation Plan (SIP). EPA also finds as adequate and 
approves the 2015 Volatile Organic Compounds (VOC) and Nitrogen Oxides 
(NOX) Motor Vehicle Emission Budgets (MVEBs) for the 
Evansville area contained in the Evansville area ozone maintenance 
plan.

DATES: This rule is effective on January 30, 2006.

ADDRESSES: EPA has established a docket for this action under Docket ID 
No. EPA-R05-OAR-2005-IN-0006. All documents in the docket are listed on 
the www.regulations.gov Web site. Although listed in the index, some 
information is not publicly available, i.e., Confidential Business 
Information (CBI) or other information whose disclosure is restricted 
by statute. Certain other material, such as copyrighted material, is 
not placed on the Internet and will be publicly available only in hard 
copy form. Publicly available docket materials are available either 
electronically through www.regulations.gov or in hard copy at the 
Environmental Protection Agency, Region 5, Air and Radiation Division, 
77 West Jackson Boulevard, Chicago, Illinois 60604. This facility is 
open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding 
Federal holidays. We recommend that you telephone Edward Doty, 
Environmental Scientist, at (312) 886-6057 before visiting the Region 5 
office.

FOR FURTHER INFORMATION CONTACT: Edward Doty, Environmental Scientist, 
Criteria Pollutant Section, Air Programs Branch (AR-18J), U.S. 
Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, 
Chicago, Illinois 60604, (312) 886-6057, doty.edward@epa.gov.

SUPPLEMENTARY INFORMATION: In the following, whenever ``we,'' ``us,'' 
or ``our'' are used, we mean the United States Environmental Protection 
Agency.

Table of Contents

I. What Is the Background for This Rule?
II. What Actions Are We Taking and When Are They Effective?
    A. Determination of Attainment and Redesignation of the 
Evansville Area To Attainment of the 8-Hour Ozone NAAQS
    B. Approval of Indiana's Ozone Maintenance Plan for the 
Evansville Area
    C. Approval and Finding of Adequacy of VOC and NOX 
Motor Vehicle Emission Budgets for the Evansville Area
    D. Effective Date of These Actions
III. Why Are We Taking These Actions?
IV. What Are the Effects of These Actions?
V. What Comments Did We Receive and What Are Our Responses?
VI. What Are Our Final Actions?
VII. Statutory and Executive Order Review

I. What Is the Background for This Rule?

    EPA has determined that ground-level ozone is detrimental to human 
health. On July 18, 1997, the EPA promulgated an 8-hour ozone NAAQS (62 
FR 38856) of 0.08 parts per million parts of air (0.08 ppm). This 
standard is violated in an area when any ozone monitor in the area 
records an average of the annual fourth-highest daily maximum 8-hour 
ozone concentrations equaling or exceeding 0.085 ppm over a three-year 
period. Ground-level ozone is not emitted directly by sources. Rather, 
emitted VOC and NOX react in the presence of sunlight to 
form ground-level ozone along with other secondary compounds. VOC and 
NOX are referred to as ``ozone precursors.''
    In accordance with section 107(d) of the CAA as amended in 1977, 
EPA designated the Evansville area (Vanderburgh and Warrick Counties) 
as an ozone nonattainment area for the 8-hour ozone NAAQS based on 
ozone data collected in this area during the 2001-2003 period. The 
Federal Register notice making this designation was signed on April 15, 
2004, and was published on April 30, 2004 (69 FR 23857).
    The Clean Air Act contains two sets of provisions--subpart 1 and 
subpart 2--that address planning and emission control requirements for 
nonattainment areas (both subparts are found in title I, part D of the 
CAA). Subpart 1 contains general, less prescriptive requirements for 
nonattainment areas governed by any NAAQS, and applies to all 
nonattainment areas. Subpart 2 contains more specific requirements for 
certain ozone nonattainment areas, and applies to ozone nonattainment 
areas classified under section 181 of the CAA.
    In the April 30, 2004 ozone designation rulemaking, EPA divided 8-
hour ozone nonattainment areas into the categories of subpart 1 
nonattainment and subpart 2 nonattainment based on their 8-hour ozone 
design values (i.e., the three-year average annual fourth-highest daily 
maximum 8-hour ozone concentrations at the worst-case ozone monitoring 
sites in the designated areas) and their 1-hour ozone design values 
(i.e., the fourth-highest daily maximum 1-hour ozone concentrations 
over the three-year period at the worst-case monitoring sites in the 
designated areas).\1\ 8-hour ozone nonattainment areas with 1-hour 
ozone design values equaling or exceeding 0.121 ppm were designated as 
classified nonattainment areas (as nonattainment areas required to meet 
the requirements of subpart 2 of the CAA). All other 8-hour 
nonattainment areas were designated as ``basic'' nonattainment areas 
subject only to the requirements of subpart 1 of the CAA.
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    \1\ The 1-hour ozone standard, 0.12 ppm, has been replaced by 
the 8-hour ozone standard, with the 1-hour ozone standard being 
revoked on June 15, 2005.
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    In the April 30, 2004 designation rulemaking, the Evansville area 
was designated as nonattainment for the 8-hour ozone standard, and was 
identified as a subpart 1 basic nonattainment area. This designation 
was based on ozone data collected in the Evansville area during the 
period of 2001-2003.
    On June 2, 2005, the State of Indiana requested redesignation of 
the

[[Page 77027]]

Evansville area to attainment of the 8-hour ozone NAAQS based on ozone 
data collected during the period of 2002-2004. This redesignation 
request also included a 10-year ozone maintenance plan for the 
Evansville area and VOC and NOX MVEBs for the Evansville 
area based on emission projections in the ozone maintenance plan.
    On September 9, 2005, EPA published a proposed rule (70 FR 53605), 
proposing to: (1) Determine that the Evansville area has attained the 
8-hour ozone NAAQS and to approve Indiana's request to redesignate the 
Evansville area to attainment of the 8-hour ozone NAAQS; (2) approve 
Indiana's ozone maintenance plan for the Evansville area; and (3) 
approve the 2015 VOC and NOX MVEBs for the Evansville area 
and notify the public that these MVEBs are adequate for purposes of 
transportation conformity. This proposed rule established a 30-day 
public comment period. EPA received several requests for a hearing and 
for extension of the comment period on the proposed rule. EPA denied 
the requests for the hearing, stating it believed that the opportunity 
to submit written comments provided an adequate opportunity for public 
input. EPA did, however, grant a seven-day extension to the public 
comment period. See 70 FR 58167 (October 5, 2005).

II. What Actions Are We Taking and When Are They Effective?

    After consideration of the comments received in response to the 
September 9, 2005 proposed rule, as described in section V below, and 
the State's final adopted SIP revision and supporting material 
(reviewed in detail in the September 9, 2005 proposed rule), we are 
taking the following actions:

A. Determination of Attainment and Redesignation of the Evansville Area 
To Attainment of the 8-Hour Ozone NAAQS

    In the September 9, 2005 proposed rule (70 FR 53605), EPA proposed 
to determine that the Evansville area had attained the 8-hour ozone 
NAAQS and to approve Indiana's request to redesignate this area to 
attainment of the 8-hour ozone NAAQS. These proposed actions were based 
on ozone data from the period of 2002-2004 and on the State's 
demonstration that the criteria for redesignation to attainment, as 
specified in section 107 of the Clean Air Act, had been satisfied. EPA 
has reviewed the ambient monitoring data for ozone consistent with the 
requirements contained in 40 CFR part 58 and recorded in EPA's 
Aerometric Information Retrieval System (AIRS) for the Evansville area 
for both the 2002-2004 ozone seasons and the 2003-2005 \2\ ozone 
seasons. On the basis of this review, EPA has determined that the area 
has attained the 8-hour ozone standard. Review of the ozone data, the 
State's submissions, and the public comments for and against the 
redesignation (see section V below) lead us to the conclusion that: (1) 
The Evansville ozone nonattainment area has attained the 8-hour ozone 
standard; and (2) the State of Indiana has met the criteria for 
redesignation of the Evansville area to attainment of the 8-hour ozone 
NAAQS. Therefore, in this final rule, we are finalizing our 
determination of attainment, and we are approving Indiana's request for 
redesignation of the Evansville area to attainment of the 8-hour ozone 
NAAQS.
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    \2\ The 2005 ozone data have not been entered into AIRS, but 
have been quality assured by the State. The State has submitted a 
summary of the peak 2005 8-hour ozone concentrations at the request 
of the EPA to respond to public comments addressed in this final 
rule.
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    The State must continue to operate an appropriate ozone monitoring 
network, in accordance with 40 CFR part 58, to verify the attainment 
status of the Evansville area. The air quality data relied on to 
determine that the area continues to attain the ozone NAAQS must be 
consistent with 40 CFR part 58 requirements and other relevant EPA 
guidance and must be recorded in EPA's AIRS.

B. Approval of Indiana's Ozone Maintenance Plan for the Evansville Area

    EPA is approving Indiana's plan for maintaining the 8-hour ozone 
NAAQS in the Evansville area through 2015 as a revision to the Indiana 
SIP. The maintenance plan meets the requirements of sections 175A and 
107(d) of the Clean Air Act. The adopted maintenance plan contains 
triggering mechanisms and contingency measures designed to promptly 
correct (or prevent) a violation of the 8-hour ozone NAAQS occurring 
after redesignation of the Evansville area to attainment of the NAAQS. 
Section 175A of the Clean Air Act requires that a maintenance plan 
include such contingency measures as EPA deems necessary to assure that 
the State will promptly correct a violation of the NAAQS that occurs 
after redesignation.
    The contingency measures listed in the adopted maintenance plan 
include, but are not limited to, the following:
    1. Lower Reid vapor pressure gasoline requirements; \3\
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    \3\ Prior to implementing lower Reid vapor pressure gasoline 
requirements, the State of Indiana would have to be granted a waiver 
to address preemption requirements under section 211(c)(4)(C) of the 
Clean Air Act.
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    2. Broader geographic applicability of existing emission control 
measures;
    3. Tightened Reasonably Available Control Technology (RACT) 
requirements on existing sources covered by EPA Control Technique 
Guidelines (CTGs) issued in response to the 1990 Clean Air Act 
amendments;
    4. Application of RACT to smaller existing sources;
    5. Vehicle Inspection and Maintenance (I/M);
    6. One or more Transportation Control Measures (TCM) sufficient to 
achieve at least a 0.5 percent reduction in actual area-wide VOC 
emissions;
    7. Alternative fuel and diesel retrofit programs for fleet vehicle 
operations;
    8. Controls on consumer products consistent with those adopted 
elsewhere in the United States;
    9. VOC and NOX emission offsets for new or modified 
sources;
    10. Increased ratio of the emission offset required for new 
sources; and,
    11. VOC and NOX emission controls on new minor sources 
(with VOC or NOX emissions less than 100 tons per year).
    Consideration and selection of one or more of the contingency 
measures will take place when a two-year average annual fourth-high 
monitored daily peak 8-hour ozone concentration of 0.085 ppm or a 
violation of the 8-hour ozone NAAQS \4\ is recorded at any monitor in 
the Evansville area after the redesignation of the Evansville area to 
attainment of the ozone NAAQS. The selected contingency measures will 
be adopted and implemented within 18 months after the close of the 
ozone season with the ozone data that trigger the need for the 
implementation of the contingency measure(s).
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    \4\ On October 20, 2005, the Indiana Department of Environmental 
Management submitted a letter verifying the State's intent to 
implement an ``Action Level Response'' and the triggering of a 
requirement to select and implement contingency measures in the 
event of a violation of the 8-hour ozone NAAQS in several areas, 
including Vanderburgh and Warrick Counties.
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    The maintenance plan estimates emissions through 2015, ten years 
after the year in which the State anticipated that EPA would complete 
rulemaking on the State's ozone redesignation request, as required by 
section 175A of the Clean Air Act. These VOC and NOX 
emission estimates are for point, area, and mobile sources in the 
Evansville area. The emissions estimates

[[Page 77028]]

demonstrate continued maintenance of the 8-hour ozone standard through 
2015. The latest available emissions information was used to project 
the emissions. The mobile source emissions estimates were developed 
using the MOBILE6 emission factor model. The State has committed to 
update the maintenance plan and maintenance demonstration eight years 
after the redesignation of the Evansville area to attainment of the 8-
hour ozone NAAQS to demonstrate maintenance of the standard for an 
additional ten years, through 2025.

C. Approval and Finding of Adequacy of VOC and NOX Motor 
Vehicle Emission Budgets for the Evansville Area

    EPA finds as adequate and approves the 2015 MVEBs of 4.20 tons per 
day for VOC and 5.40 tons per day for NOX for the Evansville 
area in the State-adopted ozone maintenance plan. These MVEBs have been 
addressed through the appropriate public involvement and review process 
without receiving adverse comment. These MVEBs meet the adequacy 
criteria, 40 CFR 93.118(e)(4), and are approvable as part of the 8-hour 
ozone maintenance plan. The approved 2015 MVEBs will replace the MVEBs 
currently used for transportation conformity analyses and 
demonstrations, as detailed in our September 9, 2005 proposed rule, 
upon the effective date of this rule. The newer MVEBs, which are being 
approved as part of the 8-hour ozone maintenance plan, are consistent 
with the goals of section 110(l) of the Clean Air Act because they set 
a tighter cap on mobile source VOC and NOX emissions for 
transportation conformity purposes, thereby limiting growth in mobile 
source emissions allowed in the area's transportation plan.
    Subsequent to the effective date of this rule, the State of Indiana 
and local planning agencies in the Evansville area will have to use the 
2015 MVEBs in all transportation conformity analyses and 
demonstrations.

D. Effective Date of These Actions

    These actions will become effective 30 days after today's 
publication of this final rule in the Federal Register.

III. Why Are We Taking These Actions?

    EPA has determined that the Evansville area has attained the 8-hour 
ozone standard. EPA has determined that the State of Indiana has 
demonstrated that all other criteria for the redesignation of the 
Evansville area from nonattainment to attainment of the 8-hour ozone 
NAAQS have been met. EPA is fully approving the ozone maintenance plan 
for the Evansville area as meeting the requirements of sections 175A 
and 107(d) of the Clean Air Act.
    In the September 9, 2005 proposed rule at 70 FR 53606, EPA 
described the applicable criteria for redesignation to attainment. 
Specifically, section 107(d)(3)(E) of the Clean Air Act allows for 
redesignation provided that: (1) The Administrator determines that the 
area has attained the applicable NAAQS; (2) the Administrator has fully 
approved the applicable implementation plan for the area under section 
110(k) of the Clean Air Act; (3) the Administrator determines that the 
improvement in air quality is due to permanent and enforceable 
reductions in emissions resulting from the implementation of the 
applicable state implementation plan, applicable Federal air pollution 
control regulations, and other permanent and enforceable emission 
reductions; (4) the Administrator has fully approved a maintenance plan 
for the area as meeting the requirements of section 175A of the Clean 
Air Act; and, (5) the state containing such area has met all 
requirements applicable to the area under section 110 and part D of the 
Clean Air Act.
    EPA has determined that the Evansville area has attained the 8-hour 
ozone NAAQS. EPA has approved all requirements in the Indiana SIP 
applicable to the Evansville area under section 110(k) of the Clean Air 
Act for purposes of redesignation. EPA has determined that the 
improvement in ozone air quality in the Evansville area is due to 
permanent and enforceable emission reductions resulting from the 
implementation of the Indiana SIP, applicable Federal air pollution 
control regulations, and other permanent and enforceable emission 
reductions. EPA is fully approving an ozone maintenance plan for the 
Evansville area meeting the requirements of section 175A of the Clean 
Air Act. Finally, EPA concludes that the State of Indiana has met all 
requirements applicable to the Evansville area under section 110 and 
part D of the Clean Air Act for purposes of redesignation. Therefore, 
EPA concludes that the State of Indiana and the Evansville area have 
met all requirements applicable to the Evansville area for purposes of 
redesignation to attainment of the 8-hour ozone NAAQS under section 107 
of the Clean Air Act.
    By finding that the ozone maintenance plan provides for maintenance 
of the 8-hour ozone NAAQS through 2015, EPA is hereby finding adequate 
and approving the 2015 VOC and NOX MVEBs contained in the 
maintenance plan. The MVEB for VOC in the Evansville area is 4.20 tons 
per day, and the MVEB for NOX in the Evansville area is 5.40 
tons per day.
    The rationale for these findings and actions is stated in this 
rulemaking and in more detail in the September 9, 2005 proposed rule, 
found at 70 FR 53605.

IV. What Are the Effects of These Actions?

    Approval of the Indiana redesignation request changes the official 
designation for the 8-hour ozone NAAQS found at 40 CFR part 81 for 
Vanderburgh and Warrick Counties, Indiana from nonattainment to 
attainment. It also incorporates into the Indiana SIP a plan for 
maintaining the 8-hour ozone NAAQS through 2015. The maintenance plan 
includes contingency measures to remedy any future violation or 
threatened violation of the 8-hour ozone NAAQS in the Evansville area, 
and includes VOC and NOX MVEBs for 2015 for the Evansville 
area.

V. What Comments Did We Receive and What Are Our Responses?

    We received comments from eight individuals and organizations 
responding to the September 9, 2005 proposed rule. Six of the 
commenters submitted comments critical of various portions of the 
proposed rule. One of the critical commenters included a petition 
signed by 125 individuals asserting that the Evansville area has an air 
quality problem requiring cleanup by the State and opposing a State 
lawsuit against the EPA.\5\ One commenter, the Vanderburgh County Ozone 
Officer, supported the proposed rule, and provided additional data and 
analyses to support the proposed rule. Another commenter supported the 
proposed rule. A summary of the comments and EPA's responses to them 
are provided below.
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    \5\ The nature of the State lawsuit against the EPA is not 
defined in the signed petition.
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Comment 1: Air Quality in 2005 Shows That the Evansville Area Continues 
To Have an Ozone Problem

    A number of commenters have expressed the concern that the current 
air quality in the Evansville area does not warrant redesignation to 
attainment of the 8-hour ozone standard. These commenters focused 
primarily on the following: (1) A number of ozone alerts \6\

[[Page 77029]]

were issued for southwestern Indiana during the summer of 2005; (2) 
certain days in 2005 had high ozone concentrations but lacked ozone 
alerts; (3) high levels of fine particulates (PM 2.5 \7\) 
occurred on a number of days in 2005; and (4) the presence of haze and 
gray skies in southern Indiana during 2005 indicated an ongoing air 
quality problem. The commenters questioned whether air quality had 
improved enough to justify redesignation and expressed a further 
concern that a redesignation to attainment would result in the removal 
of air quality monitoring equipment from the area.
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    \6\ Ozone alerts are issued based on monitored ozone 
concentrations approaching or exceeding the standard and forecasted 
meteorology favoring the formation of high ozone concentrations. 
Ozone alerts are intended to alert the public to the potential for 
high ozone concentrations. Ozone alerts are not necessarily 
associated with ozone standard exceedances. Some ozone standard 
exceedances simply fail to develop as forecasted. In addition, as 
the result of the ozone action alerts, some companies and 
individuals change operations or activities, lowering emissions, and 
possibly averting ozone standard exceedances.
    \7\ Particulate matter with nominal aerodynamic diameters of 2.5 
micrometers or less.
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    In addition, one commenter, Joanne M. Alexandrovich, Ph.D., 
Vanderburgh County Department of Public Health's Ozone Officer, 
expressed support for EPA's redesignation proposal. In so doing, she 
provided 2005 ozone data for Posey, Vanderburgh, and Warrick Counties 
showing that the Evansville area continues to meet the 8-hour ozone 
standard. This includes data containing peak 8-hour ozone 
concentrations for each monitoring site in the area for 2005 and three-
year ozone design values for each monitoring site for the period of 
2003-2005. Dr. Alexandrovich also presented ozone concentration trends 
data for each of the monitoring sites for the period of 1995-2005 to 
demonstrate a robust downward trend in ozone design values at all 
monitoring sites in the area, including at the Yankeetown site (the 
site on the property of Alcoa, Incorporated (Alcoa), see Comment/
Response 2 below) and at other sites in Warrick County, where the 
worst-case ozone monitors in the area are located.
    Dr. Alexandrovich notes that there were four exceedance days in the 
vicinity of the Evansville area in 2005 (three in the Evansville area 
and one in Posey County) and that the exceedances were recorded at 
several sites, with only one site (Boonville High School in Warrick 
County) recording exceedances on two days, and with no sites recording 
exceedances on three or more days. This shows that the fourth-high 
daily peak 8-hour ozone concentrations at all monitors in the area in 
2005 were below 0.085 ppm (a monitored exceedance level cutoff). 
Finally, Dr. Alexandrovich provided information regarding the dates of 
ozone alerts and high ozone concentrations in 2005. These data show 
that ozone alerts were issued on eight days in 2005, with only two of 
the alert days actually having exceedances of the 8-hour ozone 
standard. Two days without ozone alerts also had ozone standard 
exceedances, one in the Evansville area and the other in Posey County. 
Most ozone alert days had relatively high peak ozone concentrations, 
but had peak ozone concentrations which failed to reach ozone standard-
exceedance levels.

Response 1

    In determining whether the 8-hour ozone standard is met, the 8-hour 
ozone standard requires the use of the three most recent, consecutive 
calendar years of monitoring data. 40 CFR 50.10, appendix I, parts 2.2 
and 2.3. Thus, EPA has determined that the Evansville area has attained 
the 8-hour ozone standard based on the data for the period of 2002-
2004. EPA has also reviewed quality assured data for 2005 provided by 
the Indiana Department of Environmental Management (IDEM), and has 
determined that they show that the Evansville area continued to attain 
the 8-hour ozone standard through 2005. The quality assured peak ozone 
concentrations for 2005 are summarized in Table 1 by monitoring site as 
submitted by the State.

         Table 1.--Peak 2005 8-Hour Ozone Concentrations in the Evansville Area in Concentrations of PPM
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                                                                     First      Second       Third      Fourth
                 Site                            County              High        High        High        High
----------------------------------------------------------------------------------------------------------------
Evansville--Mill Road.................  Vanderburgh.............       0.090       0.081       0.081       0.080
Scott School--Inglefield..............  Vanderburgh.............       0.058       0.057       0.057       0.056
Booneville High School................  Warrick.................       0.096       0.085       0.081       0.080
Dayville..............................  Warrick.................       0.083       0.078       0.077       0.077
Tecumseh High School--Lynnville.......  Warrick.................       0.082       0.078       0.077       0.076
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    Although a number of ozone alerts were issued for Southwestern 
Indiana during the summer of 2005, quality assured data supplied by the 
State show that no monitors recorded fourth-high ozone concentrations 
above the 8-hour ozone standard. In addition, the 2003-2005 ozone 
design values for all monitors in the Evansville area were below the 
ozone standard violation cut-off level (below 0.085 ppm). Table 2 
documents the 2003-2005 ozone design values by monitoring site in the 
vicinity of Evansville.

     Table 2.--8-Hour Ozone Design Values in the Evansville Area in
                 Concentrations of PPM for 2003-2005 \1\
------------------------------------------------------------------------
                                                                 Ozone
           Monitoring Site                    County            Design
                                                                 Value
------------------------------------------------------------------------
Evansville--Mill Road...............  Vanderburgh...........       0.077
Scott School--Inglefield............  Vanderburgh...........       0.063
Boonville High School...............  Warrick...............       0.076
Tecumseh High School--Lynnville.....  Warrick...............       0.073 
------------------------------------------------------------------------
\1\ Ozone was also monitored at the Yankeetown-Alcoa and Dayville
  monitoring sites (both in Warrick County) during the period of 2003-
  2005. Ozone was monitored during 2003 and 2004 at the Yankeetown site,
  with an average fourth-high 8-hour daily maximum ozone concentration
  of 0.078 ppm. Ozone was monitored during 2005 at the Dayville site,
  with a fourth-high 8-hour daily maximum ozone concentration of 0.077
  ppm.

    These data show that no violations of the 8-hour ozone standard 
were monitored in the Evansville area even when 2005 ozone data are 
considered. This is true despite the commenters' observation that a 
number of ozone

[[Page 77030]]

alerts were issued in 2005 for this area. In addition, as noted by one 
of the commenters, ozone alerts were issued on eight days, but only two 
of these alert days had monitored exceedances of the ozone standard. On 
only two days lacking ozone alerts were ozone standard exceedances 
monitored (only one of these was in the Evansville area, with the other 
in Posey County, outside of the ozone nonattainment area \8\). Only one 
monitoring site, Boonville High School, recorded multiple days of ozone 
standard exceedances in 2005, but did not record a violation of the 8-
hour ozone standard during the period of 2003-2005. No monitors in the 
Evansville area have recorded violations of the 8-hour ozone NAAQS 
based on the three most recent years of quality assured monitoring 
data.\9\
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    \8\ Even though 8-hour ozone standard exceedances have been 
monitored in Posey County, this County is not in violation of the 8-
hour ozone standard.
    \9\ Occasional exceedances of the standard are allowed at any 
monitor without a violation of the 8-hour ozone NAAQS occurring. As 
long as the average annual fourth-high daily maximum 8-hour ozone 
concentrations at all relevant ozone monitoring sites in an area 
remain at or below 0.084 ppm for the most recent three-year period, 
the area is not violating the 8-hour ozone NAAQS. With multiple 
monitoring sites in an area, multiple exceedance days (exceedance of 
the standard anywhere in the monitoring system) may occur during any 
period without a violation of the ozone NAAQS actually occurring. 
That was the case for the Evansville area for 2005 and for the 
period of 2003-2005. Despite three exceedance days, the area 
continued to attain the standard, the relevant criterion for our 
determination of attainment and one of the criteria for 
redesignation to attainment.
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    A number of states and local area governments, including Indiana 
and Evansville, have chosen to activate ozone alerts when ozone 
concentrations are thought to be approaching the ozone standard and 
meteorological conditions are forecasted to be favorable for the 
formation of high ozone levels. Besides alerting the public to the 
potential for high ozone concentrations and to the potential for the 
need to change outdoor activities to avoid exposure to these high ozone 
levels, the ozone alerts also inform owners of ozone precursor emitting 
sources and the public that operations and activities should be altered 
if possible to mitigate the ozone precursor emissions. This reduces the 
potential for high ozone concentrations, and helps avoid violations of 
the ozone NAAQS. Therefore, even though ozone action alerts were issued 
on a number of days in 2005, this is not an indication of a violation 
of the ozone standard, as demonstrated by the 2003-2005 ozone data for 
the Evansville area. The quality assured monitoring data for 2002-2004 
show that the Evansville area attained the 8-hour ozone standard, and 
the quality assured 2003-2005 ozone data show that the area continues 
to attain the ozone standard. EPA is correct in determining that the 
Evansville area has attained the ozone standard, thus satisfying the 
criterion for redesignation pursuant to section 107(d)(3)(E)(i) of the 
Clean Air Act.
    The 8-hour ozone design values submitted by Dr. Alexandrovich also 
show that ozone air quality has improved in the Evansville area. Ozone 
design values for all sites for the period of 1995-2005 show a 
significant downward trend, as noted by the commenter. The areawide 
ozone design value for 2002-2004 was 0.083 ppm and the areawide ozone 
design value for 2003-2005, based on the average of the fourth-highest 
daily maximum 8-hour ozone concentrations for this period, was 0.077 
ppm. The data show several aspects of special note. All sites in the 
Evansville area exhibit essentially the same downward trend in ozone 
design values. This shows that an ozone problem has not simply shifted 
from one monitor site/area to another. In addition, the similar trends 
in ozone design values show that the peak ozone concentrations are 
reacting to common effects, including long-term downward trends in 
regional ozone precursor emissions. An increase in the downward trend 
of the ozone design values in the period of 2003-2005 at all monitoring 
sites implies that the decrease in regional NOX emissions 
resulting from EPA's NOX SIP call and other regional 
emission reductions are having a beneficial impact on ozone levels on a 
regional basis. See the response to Comment 10 below. As this commenter 
notes and we agree, the trend toward decreasing ozone design values is 
not expected to reverse in the near future as additional reductions in 
regional emissions are expected to result through the implementation of 
federally enforceable emission controls on vehicles, fuels, electric 
utilities, and other major combustion sources.
    To demonstrate the downward trend in ozone design values, Table 3 
summarizes ozone design values by monitoring site for the most recent 
three three-year periods taken from the quality assured ozone data 
supplied by the State.

  Table 3.--8-Hour Ozone Design Values for Periods of 2001-2003, 2002-
              2004, and 2003-2005 in Concentrations of PPM
------------------------------------------------------------------------
         Monitoring Site            2001-2003    2002-2004    2003-2005
------------------------------------------------------------------------
Evansville--Mill Road............        0.083        0.082        0.077
Scott School--Inglefield.........        0.077        0.073        0.063
Alcoa--Yankeetown................        0.085        0.083           NA
Dayville.........................           NA           NA    \1\ 0.077
Boonville........................        0.081        0.080        0.076
Tecumseh High School.............        0.081        0.078       0.073
------------------------------------------------------------------------
\1\ The Dayville site is only several miles from the discontinued Alcoa-
  Yankeetown site and is a replacement for the Alcoa monitor. The ozone
  design value given here is the fourth-high daily maximum 8-hour ozone
  concentration for 2005, the only year of monitoring data currently
  available for this monitoring site.

    With regard to the claims of high PM2.5 levels, it is 
noted that this rulemaking addresses only the ozone designation of the 
Evansville area. This rule does not address or affect the 
PM2.5 designation for this area, and, thus, the 
PM2.5 concentrations in this area have no bearing on EPA's 
determinations regarding the attainment status of this area for the 8-
hour ozone NAAQS.
    The comment concerned with the ending of monitoring in the 
Evansville area upon redesignation to attainment of the ozone NAAQS is 
wrong for several reasons. First, and most importantly, the State of 
Indiana has committed to continuing ozone monitoring in this area. See 
70 FR 53613 (September 9, 2005). Second, the ozone maintenance plan 
requires and depends on continued ozone monitoring during the lifetime 
of the maintenance plan. Note that the ozone maintenance plan contains 
action triggers directly tied to ozone monitoring. Under the approved

[[Page 77031]]

maintenance plan, ozone levels will be tracked and certain corrective 
actions or further analyses will be triggered if monitored ozone 
concentrations reach specified levels. To implement the ozone 
maintenance plan, the State must continue ozone monitoring in the 
Evansville area.
    With regard to haze and gray skies in southern Indiana, this issue 
also is not relevant to a redesignation of the area for the ozone 
standard, where the area has been shown to be attaining the 8-hour 
ozone standard. A number of pollutant sources lead to the formation of 
fine particulates, which can contribute to haze levels. Since the 
Evansville area is a nonattainment area for fine particulates, the 
State of Indiana is expected to assess the sources of the emissions 
leading to these fine particulates and to develop strategies and 
emission control regulations leading to attainment of the fine 
particulates standards. In doing so, the State's actions should also 
lead to reductions in haze levels and to cleaner skies. In addition, 
regional emission reductions achieved through EPA's NOX SIP 
call and Clean Air Interstate Rule (CAIR) will further lower haze 
levels and clear the skies of this area.
    With regard to the claim that the State and the City of Evansville 
failed to issue an ozone alert when it would have been warranted, the 
record of ozone alerts provided by Dr. Alexandrovich shows more 
overpredictions of high ozone levels than underpredictions (more issued 
ozone alerts on days with no ozone standard exceedances than failures 
to issue ozone alerts on days with ozone standard exceedances). This 
claim is also irrelevant to a redesignation action, which is based on 
demonstrated attainment of the standard. There is no evidence to 
support the claim that actions with respect to prior ozone alerts call 
the maintenance plan into question. The maintenance plan contains 
corrective actions that will occur if high ozone levels are monitored, 
and does not conflict with or depend upon the State's plans for issuing 
ozone alerts in the future. The fact that there were ozone alerts also 
does not indicate that the area violated the ozone standard. The ozone 
maintenance plan is designed to provide corrective actions if high 
ozone levels or violation of the standard occur after redesignation of 
the area to attainment of the NAAQS. The maintenance plan's contingency 
measures are triggered by monitored ozone levels. The triggering of the 
contingency measures in no way depends on the forecasting of high ozone 
concentrations. Therefore, the issuing of ozone alerts is in no way 
connected to the implementation of the ozone maintenance plan. The 
maintenance plan relies on monitored ozone data and not on forecasted 
concentrations. Regardless of the status of the ozone alert efforts, 
the relevant issue for redesignation is that the Evansville area has 
attained the 8-hour ozone NAAQS and has an approved plan for 
maintaining the ozone standard.

Comment 2: The Critical Ozone Monitor at the Alcoa, Incorporated Site 
Is No Longer Operating, Resulting in the Loss of Data That Would Have 
Been a Violation of the Ozone Standard in 2005

    A commenter notes that Alcoa, Incorporated (Alcoa) had sought the 
ozone redesignation while, at the same time, asking that the ozone 
monitor on its property be terminated and/or relocated to another site. 
This is a particular concern to the commenter since the Alcoa monitor 
(which was shut down in October 2004) was the monitor that had recorded 
the ozone standard violation on which the 2004 Evansville area ozone 
nonattainment designation had been based. The commenter believes that, 
had the monitor been left on the Alcoa property, it would likely have 
continued to show a violation of the ozone NAAQS during the summer of 
2005. This commenter also suggests that this redesignation request was 
originated by Alcoa. Finally, the commenter believes that EPA and the 
State are taking the approach of ``no data, no problem.''

Response 2

    The Alcoa (Yankeetown) monitor operated through the end of the 2004 
ozone season. Data from the Alcoa monitor were considered both in 
designating the Evansville area as nonattainment based on 2001-2003 
data and in EPA's determination that the area attained the 8-hour ozone 
standard based on 2002-2004 data. The State considered this monitor to 
represent ambient air and requested Alcoa to quality assure the data 
from this site, meeting State monitoring standards, so that these data 
could be considered to be on par with the ozone data from other 
monitors in the Evansville area and in the State. Alcoa disagreed with 
the State, arguing that this monitor does not represent ambient air. 
Alcoa objected to and challenged the designation of the Evansville area 
as an 8-hour ozone nonattainment area based on the ozone monitoring at 
the Alcoa site. Alcoa terminated the monitor at the end of the 2004 
ozone season and the State located a new ozone monitor very close to 
the Alcoa site, but off the premises of Alcoa. This new monitor, the 
Dayville site, was operated in 2005.
    Prior to the establishment of the Dayville ozone monitoring site, 
EPA was given the opportunity to review the characteristics of the 
Dayville site relative to the characteristics of the Alcoa site. The 
proximity of the two monitoring sites and the similarity of the 
emissions near the monitoring sites (particularly the similarity and 
spatial distribution of NOX emissions close to the 
monitoring sites) led us to the conclusion that the two monitoring 
sites were equivalent. We have seen no data to the contrary.
    The ozone trends data provided by Dr. Alexandrovich, as discussed 
in Comment/Response 1, indicate that the Dayville monitoring data may 
be generally considered in conjunction with the Alcoa data to assess 
the long-term trend in the 8-hour ozone data for this area. The Alcoa/
Dayville ozone data show an ozone trend very similar to the ozone 
trends for other monitors in the Evansville region. The 2005 data for 
Dayville fit well with the prior data for the Alcoa site to produce an 
ozone trend that matches those from other long-term sites in the area. 
If the Dayville site was significantly different in local emission 
characteristics and ozone response relative to the Alcoa site, one 
might expect the short-term ozone trend (2004-2005) for this site pair 
to be significantly different from the ozone trends for the long-term 
sites. This is not the case. Based on this observation and considering 
the close proximity and similarities of the Alcoa and Dayville 
monitoring sites and the fact that the Dayville monitor recorded a 
fourth-high daily maximum 8-hour ozone concentration of 0.077 ppm in 
2005, we see no basis to assume or to speculate that the Alcoa site 
would have recorded a violation of the 8-hour ozone standard based on 
2003-2005 ozone data. Therefore, we disagree with the commenters on 
this point.
    EPA can base its determination on whether the standard has been met 
only on available ozone monitoring data and not on speculation. There 
is no evidence that air quality at the Alcoa monitor would have 
violated the 8-hour ozone standard in 2005. On the contrary, the data 
show no violation of the ozone standard during the period of 2002-2004 
for the Alcoa monitor, and no exceedances of the 8-hour ozone standard 
at the replacement Dayville monitor in 2005. If anything, the available 
data indicate that the Alcoa site would not have violated the 8-hour 
ozone standard in 2005. At minimum, we cannot conclude that a violation 
of

[[Page 77032]]

the 8-hour ozone standard would have been recorded at the Alcoa monitor 
in 2005. The termination of the Alcoa monitor and its replacement by 
the Dayville monitor do not affect the eligibility of the Evansville 
area to qualify for redesignation. The available ozone data support 
this redesignation, and the State has demonstrated that the area has 
attained the 8-hour ozone NAAQS.
    While EPA acknowledges that Alcoa chose to discontinue monitoring 
on its property, it is the State of Indiana--and not Alcoa--that 
developed, adopted, and submitted the ozone redesignation request. As 
discussed above, EPA believes that the new, nearby ozone monitor at 
Dayville provides ozone data equivalent those produced by the Alcoa-
Yankeetown monitor.
    The State is not exhibiting an attitude of ``no data, no problem,'' 
and has replaced the terminated Alcoa monitoring site with the Dayville 
monitoring site. The State has supported the original 8-hour ozone 
nonattainment designation for Warrick County (the county in which the 
Alcoa site was located), and has supported maintaining an ozone monitor 
in this area, recognizing that this area has a potential for relatively 
high ozone concentrations. This is why the Dayville ozone monitoring 
site was selected and implemented.
    EPA is not taking the approach of ``no data, no problem.'' First, 
EPA (along with the State) considered the data from the Alcoa site in 
both its original ozone designation of the area and in determining that 
the area subsequently attained the 8-hour ozone standard. Second, EPA 
has routinely required states to operate and maintain adequate ozone 
monitoring networks to record ozone concentrations and to maintain such 
networks after redesignation to assure maintenance of the standard. 
EPA's guidance provides that an area's maintenance plan should contain 
provisions for continued operation of air quality monitors to verify 
continued attainment, and that the state should continue to operate an 
appropriate air quality monitoring network in accordance with 40 CFR 
part 58. Memorandum of John Calcagni, ``Procedures for Processing 
Requests to Redesignate Areas to Attainment,'' September 4, 1992. The 
State has committed to continue operating an appropriate monitoring 
network in the Evansville area. IDEM has committed to continue 
operating and maintaining an approved ozone monitoring network in 
accordance with 40 CFR part 58 through the 10-year maintenance period.

Comment 3: High Ozone Concentrations Have Been Monitored in Downwind 
Perry County, and This Monitoring Site Should Be Considered in This 
Ozone Redesignation Review as Part of the Evansville Area

    Several commenters expressed concerns about high ozone 
concentrations monitored at the Leopold monitor in Perry County. The 
commenters believe that during the first two years that the Leopold 
monitor was operated, it showed exceedances of the 1-hour ozone 
standard. Because the monitor was removed before it collected three 
years of ozone data, the data for this monitoring site were not used to 
designate Perry County as nonattainment for the 1-hour ozone standard. 
The monitor has been replaced, although at a different site, and the 
new monitor has recorded exceedances of the 8-hour ozone standard, but 
has not collected three years of data showing a violation of the 8-hour 
ozone NAAQS. The commenters believe that the Leopold monitoring site 
should be considered to be part of the Evansville area, and that the 
Leopold data should be considered in EPA's determination of the ozone 
attainment status for the Evansville area. One of these commenters 
wants a commitment from the EPA that the Leopold monitor will become 
part of the Evansville ozone monitoring network, and that such action 
will be considered as part of the ozone maintenance plan addressed in 
EPA's final rule on Indiana's ozone redesignation request.
    Dr. Alexandrovich, the Vanderburgh County Ozone Officer, notes that 
an ozone monitor was operated in Perry County from 1998 through 2001, 
Aerometric Information Retrieval System (AIRS) site 18-123-0008. 
Although ozone levels were elevated at this site, no exceedances of the 
1-hour ozone standard were monitored at this site through the 2001 
ozone season. After the 2001 ozone season (April-September in Indiana), 
this monitoring site was shut down. In 2004, a new monitoring site was 
established at Leopold, AIRS site 18-123-0009. In 2005, this monitor 
recorded exceedances of the 8-hour ozone standard on four days.\10\ 
Analyses of wind speeds and directions by hour (transport analyses) for 
the high ozone days in 2005 show that the Evansville area was not a 
likely source area for the ozone standard exceedances on three of the 
four days.
---------------------------------------------------------------------------

    \10\ No exceedance of the 8-hour ozone standard was monitored at 
this site in 2004. The average fourth-high daily maximum 8-hour 
ozone concentration for this site is 0.082 ppm for the period of 
2004-2005 based on quality assured data supplied by the State.
---------------------------------------------------------------------------

Response 3

    The Leopold monitoring site should not be considered to be part of 
the Evansville area. The boundary of the Evansville nonattainment area 
was set in EPA's designation rulemaking of April 30, 2004, and EPA is 
not re-visiting that rulemaking in this final rule. In its designation 
rulemaking, EPA evaluated the boundary of the Evansville nonattainment 
area in accordance with the statute, EPA guidance, and the criteria 
that EPA applied nationally, and we considered all relevant factors. 
See 69 FR 23858. Perry County, located to the east and separated from 
the Evansville area by Spencer County, is designated as attainment for 
the 8-hour ozone standard. See 40 CFR 81.315. There is no showing that 
Perry County is monitoring a violation of the 8-hour ozone standard. 
There is, thus, no possibility of showing that the Evansville area is 
contributing to a violation of the ozone standard in Perry County.
    As noted by Dr. Alexandrovich, wind speed and direction analyses 
for high ozone days in 2005 indicate that the Evansville area emissions 
may be impacting the Leopold monitoring site on only one out of four 
exceedance days during 2005 at this site. Areas south and east of the 
Leopold monitor (and not west in the direction of the Evansville area) 
appear to be the primary emission source areas that may be affecting 
Perry County on three of the four exceedance days. These data show that 
the Evansville area cannot be held responsible for the majority of the 
days on which there are high levels of ozone at the Leopold monitoring 
site. It appears that a number of other ozone precursor source areas in 
Indiana, Kentucky, and other upwind areas may be affecting ozone 
concentrations in Perry County.
    For all of these reasons, we disagree with the commenters' 
assertions that Perry County should be part of the Evansville area and 
that the Leopold monitoring data should change EPA's decisions on the 
attainment and maintenance status of the Evansville area.
    The 1-hour ozone concentrations monitored in Perry County have no 
bearing on our decision regarding the attainment status of the 
Evansville area for the 8-hour ozone NAAQS. We are not considering 1-
hour ozone concentrations in any decision regarding 8-hour ozone 
redesignations. In addition, as of June 15, 2005, the 1-

[[Page 77033]]

hour ozone NAAQS was revoked and no longer exists.
    There is no showing that Perry County and the other Counties cited 
by the commenters are monitoring violations of the 8-hour ozone 
standard. Therefore, neither EPA nor the State is failing to disclose a 
current violation of the standard in this area. Monitored air quality 
data for Perry County are available to the public through AIRS or 
through the State's data system and air quality data summaries. In 
addition, it should be noted that the adequacy of monitoring in areas 
which are outside of the Evansville area, and which have not been shown 
to affect the determination of attainment in the Evansville area, is 
not relevant to this rulemaking.

Comment 4: There Was Unusually Cool Meteorology in 2003 and 2004 That 
Led to Abnormally Low Peak Ozone Concentrations

    Several commenters have asserted that the Evansville area 
experienced unusually cool weather in 2003 and 2004, and that EPA 
should consequently reject the State's redesignation request. A 
commenter further states that redesignation guidance issued by the EPA 
in September 1992 is clear in requiring that a redesignation to 
attainment must not be a result of ``unusual meteorology.'' On the 
other hand, 2002 data show clear exceedances of the 8-hour ozone 
standard. This commenter also believes that the summer of 2005 clearly 
shows that, under the right conditions, the Evansville Metropolitan 
Statistical Area (MSA) will continue to exceed the 8-hour ozone 
standard.
    Another commenter, Dr. Alexandrovich, notes that meteorological 
statistics indicate that over the last 10 years, with a few exceptions, 
the weather in the Evansville area was within normal ranges. The 
commenter presents data on the departure of daily average temperatures 
from normal daily temperature averages, the departure of monthly 
average temperatures from normal monthly average temperatures, and the 
departure of monthly precipitation levels from normal monthly 
precipitation levels for the April through September periods of 1995 
through 2005 to support conclusions regarding whether 2003 and 2004 
were atypical years unusually favorable to lower peak ozone 
concentrations. The commenter also documents the ozone standard 
exceedance days with respect to departures of daily average 
temperatures from normal daily average temperatures. The data, in the 
accumulative, indicate that: (1) The weather in 2003 and 2004 was not 
atypically colder or drier/wetter than the weather during the ozone 
seasons in other years during the period of 1995-2005; (2) ozone 
standard exceedance days were not limited to days with atypically high 
temperatures; and (3) ozone exceedance trends (in number of exceedance 
days per year) were not associated with year-to-year trends in peak 
daily temperatures or precipitation. In other words, meteorological 
trends or deviations from normal meteorological conditions cannot 
explain the observed trends in peak ozone concentrations. This leaves 
one to conclude that the downward trend in peak ozone concentrations in 
the Evansville area is due to emission decreases in this area or in the 
surrounding region.

Response 4

    As part of the State's ozone redesignation request, the State 
documented a temperature analysis conducted to show that unusually 
favorable meteorology was not responsible for the observed air quality 
improvement. In this analysis, the State considered temperatures during 
the ozone-conducive months of May through September for the period of 
1971-2000 versus the same months during the attainment period, 2002-
2004. Temperature data were reviewed for a number of weather stations, 
including Indiana weather stations at: Bloomfield; Boonville; Dubois; 
Freelandville; Huntingburg; Mount Vernon; Shoals; Saint Meinrad; and 
Washington, along with temperature data supplied by the Evansville 
National Weather Service office. The temperature data were used to 
calculate the monthly average number of 90 degree days \11\ during the 
period of 1995-1999. Temperature data were also used to determine the 
monthly normal maximum temperatures for the summer months for the 
period of 1971-2004. Monthly maximum temperatures were compared by 
month for various years for 1996 through 2004. Based on these analyses, 
it was concluded that the temperatures during the 2002 summer months of 
May, June, July, August, and September, were 1 to 2 percent higher than 
the long-term monthly norms, while the monthly maximum temperatures 
during the 1996, 1997, 2000, 2001, 2003, and 2004 summer months were 1 
to 5 percent lower than the long-term averages. On average, the monthly 
maximum temperatures in the summer months of 2003 and 2004 were 3 
percent and 2 percent below the long-term averages, respectively, 
whereas, on average, the monthly maximum temperatures in 2002 were 2 
percent higher than the long-term averages. It should be noted that 
monthly maximum temperature ranges (when compared to the long-term 
monthly average maximum temperatures) were essentially identical 
between the 2001-2003 period used to designate the Evansville area as 
nonattainment for the 8-hour ozone NAAQS and the 2002-2004 attainment 
period. This is one indicator that temperature differences between 
various years were not the key factor in the observed air quality 
improvement.
---------------------------------------------------------------------------

    \11\ Days with peak temperatures equal to or greater than 90 
degrees Fahrenheit at any of the meteorological monitoring sites 
considered.
---------------------------------------------------------------------------

    The State also compared the number of 90 degree days during the 
summer months for each year during the period of 1995-2004 to the 
``normal'' number of such days (the average for all years in this 
period) for the Evansville Regional Airport. The State compared these 
data to the number of 8-hour ozone standard exceedance days for each 
year. These data point to 2002 as being an abnormally warm summer, 
having a higher than average number of ozone standard exceedance days, 
whereas 2003 and 2004 were below average in warm summer days, but with 
numbers of ozone standard exceedance days more indicative of the 
averages during the period of 2000-2004, excluding 2002. The State 
concludes from these data that a greater number of ozone exceedance 
days per year correlates with a greater number of 90 degree days per 
year. This analysis supports a connection between meteorology and the 
number of ozone standard exceedance days per year, but does not support 
or address the case that 2003 and 2004 were atypically cool years. The 
State does conclude that, based on long-term trends, the annual number 
of 8-hour ozone standard exceedance days shows a greater downward trend 
than the annual number of 90 degree days. That is, the local summer 
climate is cooling, but the ozone air quality is improving at a faster 
rate, implying that emission decreases are responsible for the air 
quality improvement rather than the long-term change in meteorology.
    To further consider this issue, we refer to the temperature and 
precipitation analyses documented by Dr. Alexandrovich (other 
commenters made assertions without providing supporting data). This 
commenter analyzed the ozone season departure of daily average 
temperatures from normal and the long-term daily average temperatures 
for each year during the

[[Page 77034]]

period of 1996-2005. This analysis also indicated the departures of 
daily average temperatures on 8-hour ozone standard exceedance days 
during this period. Considering temperature variations throughout the 
ozone seasons, the commenter concluded that 2003, 2004, and 2005 were 
not atypically colder during the ozone season than other years in the 
1996-2005 period. No years showed departures of daily average 
temperatures outside of the typical meteorological variability range. 
Additionally, the commenter concluded that ozone standard exceedances 
occurred on days with both above and below average daily peak 
temperatures, but do preferentially occur over periods of increasing 
temperatures, reflecting the influence of warming air masses on 
increasing ozone levels.
    Dr. Alexandrovich also analyzed the departures of average monthly 
temperatures and precipitation levels from normal levels during the 
ozone seasons for the period of 1995-2005 along with the annual number 
of 8-hour ozone standard exceedance days for this period. This analysis 
failed to show any connection between monthly average temperatures and 
monthly precipitation and the annual number of ozone standard 
exceedance days. This commenter concludes that the weather over the 
last 10 years in the Evansville area was within normal ranges and no 
``unusually favorable meteorology'' influenced the downward trend in 
peak ozone levels (towards cleaner air).
    Given the data supplied by the State and Dr. Alexandrovich and the 
lack of data countering their conclusions, we see no support for the 
commenter's claim that the improvement in ozone air quality was due to 
unusually favorable meteorology. See the John Calcagni memorandum at 4. 
We agree that meteorology does influence peak ozone concentrations, but 
we see greater evidence in this case that emission reductions, both 
local and, more significantly, regional, were responsible for the 
reduction in peak ozone concentrations leading to attainment of the 8-
hour ozone NAAQS. See our response to Comment 10 below. Therefore, we 
disagree with the commenters that unusually favorable meteorology led 
to attainment of the ozone NAAQS.

Comment 5: The Maintenance Plan Failed To Address Surrounding Counties, 
and Emission Increases in These Surrounding Areas and in the Evansville 
Area Will Threaten Maintenance of the Ozone Standard

    A commenter questions why the maintenance plan did not include the 
surrounding counties in the Evansville MSA and why the surrounding 
counties were not included in the original ozone nonattainment area.
    A commenter asserts that, if EPA allows this redesignation, this 
will allow increases in pollution levels instead of reducing emissions 
as required by the Clean Air Act.
    A commenter notes that there is nothing in the State's maintenance 
plan that deals with counties besides Warrick and Vanderburgh Counties. 
The commenter contends that additional counties should have been 
included in the original Evansville nonattainment area as required by 
EPA's designation guidance. The commenter claims that EPA's guidance 
required all of the counties in the MSA to be treated equally and to be 
included in the nonattainment area, and that EPA failed to follow its 
own guidance, excluding counties in Indiana and Kentucky from the 
nonattainment area that are part of the Evansville MSA. As a result of 
this, the commenter argues that nothing in the maintenance plan will 
apply to the ``other'' counties, whose emissions impact the ozone 
levels in the entire region.
    A commenter asserts that the failure to include the other counties 
will bode poorly for the health of citizens in this region since new 
coal-fired power plants are proposed for Henderson County, Kentucky, 
just a few miles from the current ozone nonattainment area. The 
commenter claims that, had EPA followed its own guidance in 
establishing the original nonattainment area, the prospect of new coal-
fired power plants for the region would have been different, if not 
impossible.
    Several commenters demand that all counties in the Evansville MSA 
comply with the Indiana maintenance plan. The commenters believe that 
to let these counties ``off the hook'' when they have emission sources 
that are larger than anything in Vanderburgh County is outside of the 
spirit, legal guidance, and rules of the Clean Air Act. A commenter 
contends that Gibson and Posey Counties in Indiana and Henderson County 
in Kentucky should also be included in the maintenance plan for the 
Evansville area.