[Federal Register: May 31, 2007 (Volume 72, Number 104)]
[Proposed Rules]
[Page 30435-30456]
[DOCID:fr31my07-31]

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Part II

Environmental Protection Agency

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40 CFR Parts 52 and 81

Approval and Promulgation of Implementation Plans and Designation of
Areas for Air Quality Planning Purposes; Indiana; Redesignation of Lake
and Porter Counties to Attainment of the 8-Hour Ozone Standard and
Approval of Base Year Emission Inventories; Proposed Rule

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Parts 52 and 81

[EPA-R05-OAR-2006-0474; FRL-8317-1]

Approval and Promulgation of Implementation Plans and Designation
of Areas for Air Quality Planning Purposes; Indiana; Redesignation of
Lake and Porter Counties to Attainment of the 8-Hour Ozone Standard and
Approval of Base Year Emission Inventories

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: On September 12, 2006, the Indiana Department of Environmental
Management (IDEM) submitted a request for EPA approval of a
redesignation of Lake and Porter Counties to attainment of the 8-hour
ozone National Ambient Air Quality Standard (NAAQS) and of an ozone
maintenance plan for this area as a revision to the Indiana State
Implementation Plan (SIP). EPA is proposing to determine that the
Chicago-Gary-Lake County, Illinois-Indiana (IL-IN) 8-hour ozone
nonattainment area, which includes Lake and Porter Counties, has
attained the 8-hour ozone NAAQS. EPA is proposing to approve Indiana's
ozone maintenance plan for Lake and Porter Counties as a revision to
the SIP. EPA is proposing to approve Volatile Organic Compounds (VOC)
and Nitrogen Oxides (NOX) Motor Vehicle Emission Budgets
(MVEBs) for Lake and Porter Counties as supported by the ozone
maintenance plan. EPA is proposing to approve Indiana's 2002 base year
VOC and NOX emission inventories for Lake and Porter
Counties. EPA is proposing to approve into the Indiana SIP the VOC and
NOX periodic emission inventories for 1999, 2002, and 2004.
Finally, EPA is proposing to approve the redesignation of Lake and
Porter Counties to attainment of the 8-hour ozone NAAQS.

DATES: Comments must be received on or before July 2, 2007.

ADDRESSES: Submit your comments, identified by Docket ID No. EPA-R05-
OAR-2006-0474, by one of the following methods:
     http://www.regulations.gov: Follow the on-line instructions for

submitting comments.
     E-mail<EMAIL_ADDRESS>     Fax:<PHONE_NUMBER>.
     Mail: John M. Mooney, Chief, Criteria Pollutant Section,
Air Programs Branch (AR-18J), U.S. Environmental Protection Agency, 77
West Jackson Boulevard, Chicago, Illinois 60604.
     Hand Delivery: John M. Mooney, Chief, Criteria Pollutant
Section, Air Programs Branch (AR-18J), U.S. Environmental Protection
Agency, 77 West Jackson Boulevard, Chicago, Illinois. Such deliveries
are only accepted during the Regional Office's normal hours of
operation, and special arrangements should be made for deliveries of
boxed information. The Regional Office's official hours of operation
are Monday through Friday, 8:30 a.m. to 4:30 p.m., excluding Federal
holidays.
    Instructions: Direct your comments to Docket ID No. EPA-R05-OAR-
2006-0474. EPA's policy is that all comments received will be included
in the public docket without change and may be made available online at
http://www.regulations.gov, including any personal information provided,

unless the comment includes information claimed to be Confidential
Business Information (CBI) or other information whose disclosure is
restricted by statute. Do not submit information that you consider to
be CBI, or otherwise protected, through http://www.regulations.gov or e-mail.

The http://www.regulations.gov Web site is an ``anonymous access'' system,

which means EPA will not know your identity or contact information
unless you provide it in the body of your comment. If you send an e-
mail comment directly to EPA without going through http://www.regulations.gov,

your e-mail address will be automatically captured and included as part
of the comment that is placed in the public docket and made available
on the Internet. If you submit an electronic comment, EPA recommends
that you include your name and other contact information in the body of
your comment and with any disk or CD-ROM you submit. If EPA cannot read
your comment due to technical difficulties and cannot contact you for
clarification, EPA may not be able to consider your comment. Electronic
files should avoid the use of special characters and any form of
encryption, and should be free of any defects or viruses.
    Docket: All documents in the docket are listed in the
http://www.regulations.gov index. Although listed in the index, some

information is not publicly available, e.g., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, will be publicly available only in hardcopy.
Publicly available docket materials are available either electronically
in http://www.regulations.gov or in hardcopy 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.
It is recommended that you telephone Edward Doty, Environmental
Scientist, at<PHONE_NUMBER>, before visiting the Region 5 office.

FOR FURTHER INFORMATION CONTACT: Edward Doty, Environmental Scientist,
Criteria Pollutant Section, Air Programs Branch (AR-18J), Environmental
Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago,
Illinois 60604,<PHONE_NUMBER><EMAIL_ADDRESS>
SUPPLEMENTARY INFORMATION: Throughout this proposed rule whenever
``we,'' ``us,'' or ``our'' is used, we mean the EPA. This supplementary
information section is arranged as follows:

I. What Actions Is EPA Proposing To Take?
II. What Is the Background for These Actions?
III. What Is the Impact of a December 22, 2006 United States Court
of Appeals Decision Regarding EPA's Phase 1 Ozone Implementation
Rule on This Proposed Rule?
    A. Requirements Under the 8-Hour Ozone Standard
    B. Requirements Under the 1-Hour Ozone Standard
IV. What Are the Criteria for Redesignations to Attainment of the 8-
Hour Ozone NAAQS?
V. What Are EPA's Analyses of the State's Redesignation Request and
Maintenance Plan and What Are the Bases for EPA's Proposed Actions?
    A. Have Lake and Porter Counties and the Entire Chicago-Gary-
Lake County, IL-IN Nonattainment Area Attained the 8-Hour Ozone
NAAQS and 1-Hour Ozone NAAQS?
    1. Attainment of the 8-Hour Ozone NAAQS
    2. Attainment of the 1-Hour Ozone NAAQS
    B. Has the State of Indiana Committed To Maintain the Ozone
Monitoring System in Lake and Porter Counties?
    C. Have Lake and Porter Counties and the State of Indiana Met
All of the Requirements of Section 110 and Part D of the CAA
Applicable for Purposes of Redesignation, and Do Lake and Porter
Counties Have a Fully Approved SIP Under Section 110(k) of the CAA
for Purposes of Redesignation to Attainment?
    1. Lake and Porter Counties Have Met All Requirements of Section
110 and Part D of the CAA Applicable for Purposes of Redesignation
for the 8-Hour NAAQS
    a. Section 110 and General SIP Requirements
    b. Part D SIP Requirements Under the 8-Hour Ozone Standard
    2. Lake and Porter Counties Have a Fully Approved SIP Under
Section 110(k) of the CAA

    D. Have Lake and Porter Counties Met the Part D Nonattainment
Area and Section 110 Requirements Under the 1-Hour Ozone Standard?
    E. Are the Air Quality Improvements in Lake and Porter Counties
and in the Chicago-Gary-Lake County, IL-IN Nonattainment Area Due to
Permanent and Enforceable Emission Reductions Resulting From the
Implementation of the Indiana SIP and Applicable Federal Air
Pollution Control Regulations and Other Permanent and Enforceable
Emission Reductions?
    F. Do Lake and Porter Counties Have a Fully Approvable Ozone
Maintenance Plan Pursuant to Section 175A of the CAA?
    1. What Is Required in an Ozone Maintenance Plan?
    2. What Are the Attainment Emission Inventories for Lake and
Porter Counties?
    a. Point Sources
    b. Area Sources
    c. On-Road Mobile Sources
    d. Non-Road Mobile Sources
    3. Has the State Demonstrated Maintenance of the Ozone Standard
in Lake and Porter Counties and in the Chicago-Gary-Lake County, IL-
IN Ozone Nonattainment Area?
    4. What Is the Contingency Plan for Lake and Porter Counties?
    a. Verification of Continued Attainment
    b. Contingency Plan
    5. Has the State Committed To Update the Ozone Maintenance Plan
in Eight Years After the Redesignation of Lake and Porter Counties
to Attainment of the 8-Hour Ozone NAAQS?
VI. Has the State Adopted Acceptable MVEBs for the End Year of the
Ozone Maintenance Period Which Can Be Used To Support Transportation
Conformity Determinations?
    A. How Are the MVEBs Developed and What Are the MVEBs for Lake
and Porter Counties?
    B. Are the MVEBs Approvable?
VII. Modeled Attainment of the Ozone Standard
    A. Regional Ozone Modeling Results
    B. Temperature--Ozone Exceedance Frequency Study
VIII. Review of Indiana's 2002 Base Year Emissions Submittal
IX. What Are EPA's Proposed Actions?
X. Statutory and Executive Order Reviews

I. What Actions Is EPA Proposing To Take?

    We are proposing to take several related actions for Lake and
Porter Counties, Indiana. First, we are proposing to determine that the
Chicago-Gary-Lake County, IL-IN ozone nonattainment area, including
Lake and Porter Counties in Indiana, has attained the 8-hour ozone
NAAQS.
    Second, we are proposing to approve Indiana's request to
redesignate the Indiana portion of the Chicago-Gary-Lake County, IL-IN
ozone nonattainment area (Lake and Porter Counties) to attainment of
the 8-hour ozone NAAQS. We have determined that the State of Indiana
and Lake and Porter Counties have met the CAA requirements for such a
redesignation under section 107(d)(3)(E). EPA is proposing in this
notice to approve Indiana's 2002 base year VOC and NOX
emission inventories for Lake and Porter Counties as meeting the base
year emissions inventory requirements of the CAA and as a revision to
the Indiana SIP. EPA is also proposing to approve into the Indiana SIP
the VOC and NOX periodic inventories for 1999, 2002 and
2004, pursuant to section 182(a)(3)(A) of the CAA under the 1-hour
standard.
    Third, we are proposing to approve Indiana's ozone maintenance plan
for Lake and Porter Counties as a revision of the Indiana SIP. The
maintenance plan, which meets the requirements of section 175A of the
CAA, is designed to keep Lake and Porter Counties and the Chicago-Gary-
Lake County ozone nonattainment area in attainment of the 8-hour ozone
NAAQS through 2020. As supported by and consistent with the ozone
maintenance plan, we are also proposing to approve the 2010 and 2020
VOC and NOX MVEBs for Lake and Porter Counties for
transportation conformity determination purposes.
    Finally, in response to a December 22, 2006, decision of the United
States Court of Appeals vacating EPA's Phase 1 ozone implementation
rule, we are proposing to find that, if the 1-hour ozone standard is
deemed to be reinstated, Lake and Porter Counties would also qualify
for a redesignation to attainment of the 1-hour ozone standard.

II. What Is the Background for These Actions?

    EPA has determined that ground-level ozone is detrimental to human
health. On July 18, 1997, EPA promulgated an 8-hour ozone NAAQS (62 FR
38856) of 0.08 parts per million parts of air (0.08 ppm) (80 parts per
billion (ppb)).\1\ This 8-hour ozone standard replaced a prior 1-hour
ozone NAAQS, which was promulgated on February 8, 1979 (44 FR 8202) and
which EPA revoked on June 15, 2005 (69 FR 23858).
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    \1\ This standard is violated in an area when any ozone monitor
in the area records 8-hour ozone concentrations with a three-year
average of the annual fourth-highest daily maximum 8-hour ozone
concentrations equaling or exceeding 85 ppb. See 40 CFR 50.10.
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    Ground-level ozone is not emitted directly by emission sources.
Rather, emitted NOX and VOC react in the presence of
sunlight to form ground-level ozone along with other secondary
compounds. NOX and VOC are referred to as ``ozone
precursors.'' \2\ Control of ground-level ozone concentrations is
achieved through controlling VOC and NOX emissions.
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    \2\ Carbon Monoxide (CO) is also a minor precursor in the
formation of ozone.
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    Section 107 of the CAA required EPA to designate as nonattainment
any area that violated the 8-hour ozone NAAQS. The Federal Register
notice promulgating the 8-hour ozone designations and classifications
was published on April 30, 2004 (69 FR 23857).
    The CAA contains two sets of provisions--subpart 1 and subpart 2--
that address planning and emission control requirements for
nonattainment areas. Both are found in title I, part D of the CAA.
Subpart 1 contains general, less prescriptive requirements for all
nonattainment areas of pollutants governed by NAAQS. 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 designation rulemaking, EPA divided 8-hour
ozone nonattainment areas into the categories of subpart 1
nonattainment (``basic'' nonattainment) and subpart 2 nonattainment
(``classified'' nonattainment). EPA based this division on the areas'
8-hour ozone design values (i.e., on the three-year averages of the
annual fourth-highest daily maximum 8-hour ozone concentrations at the
worst-case monitoring sites in the designated areas) and on their 1-
hour ozone design values (i.e., on the fourth-highest daily maximum 1-
hour ozone concentrations over the three-year period at the worst-case
monitoring sites in the designated areas).\3\ EPA classified 8-hour
ozone nonattainment areas with 1-hour ozone design values equaling or
exceeding 121 ppb as subpart 2, classified nonattainment areas. EPA
classified all other 8-hour nonattainment areas as subpart 1, basic
nonattainment areas. The basis for area classification was defined in a
separate April 30, 2004 final rule (the Phase 1 implementation rule)
(69 FR 23951).\4\
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    \3\ The 8-hour ozone design value and the 1-hour ozone design
value for each area were not necessarily recorded at the same
monitoring site. The worst-case monitoring site for each ozone
concentration averaging time was considered for each area.
    \4\ It should be noted that the United States Court of Appeals
for the District of Columbia Circuit recently vacated EPA's April
30, 2004 ``Final Rule to Implement the 8-Hour Ozone National Ambient
Standard'' (the Phase 1 implementation rule). South Coast Air
Quality Management District v. EPA, 472 F.3d 882(D.C. Cir. 2006).
EPA explains its views of the potential impact of this decision in
section III, below.

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    Emission control requirements for classified nonattainment areas
are linked to area classifications. Areas with more serious ozone
pollution problems are subject to more prescribed requirements and
later attainment deadlines. The prescribed emission control
requirements are designed to bring areas into attainment by their
specified attainment dates.
    In the April 30, 2004 ozone designation/classification rulemaking,
EPA designated Lake and Porter Counties, as part of the Chicago-Gary-
Lake County, IL-IN area, as a subpart 2 moderate nonattainment area for
the 8-hour ozone NAAQS. This designation was based on ozone data
collected during the 2001-2003 period.
    On September 12, 2006, the State of Indiana requested redesignation
of Lake and Porter Counties to attainment of the 8-hour ozone NAAQS.
This redesignation request was submitted by the State subsequent to
conducting a public review process for the redesignation request and
ozone maintenance plan and subsequent to the State's adoption of the
ozone maintenance plan.

III. What Is the Impact of a December 22, 2006 United States Court of
Appeals Decision Regarding EPA's Phase 1 Ozone Implementation Rule on
This Proposed Rule?

    On December 22, 2006, the United States Court of Appeals for the
District of Columbia Circuit (the Court) vacated EPA's Phase 1
implementation rule (Phase 1 Rule) for the 8-hour ozone standard (69 FR
23951, April 30, 2004). South Coast Air Quality Management Dist. v.
EPA, 472 F.3d 882 (D.C. Cir. 2006). The Court held that certain
provisions of EPA's Phase 1 Rule were inconsistent with the
requirements of the CAA. The Court rejected EPA's reasons for
implementing the 8-hour ozone standard in nonattainment areas under
subpart 1 in lieu of subpart 2 of Title I, part D of the CAA. The Court
also held that EPA improperly failed to retain four measures required
for 1-hour ozone nonattainment areas under the anti-backsliding
provisions of the regulations: (1) Nonattainment area New Source Review
(NSR) requirements based on an area's 1-hour nonattainment
classification; (2) section 185 penalty fees for 1-hour severe or
extreme ozone nonattainment areas; (3) measures to be implemented
pursuant to section 172(c)(9) or 182(c)(9) of the CAA, on the
contingency of an area not making reasonable further progress toward
attainment of the 1-hour ozone NAAQS, or failing to attain that NAAQS;
and, (4) conformity requirements for certain types of Federal actions.
The Court upheld EPA's authority to revoke the 1-hour ozone standard
provided that there were adequate anti-backsliding provisions.
    This section sets forth EPA's views on the potential effect of the
Court's ruling on this redesignation action. For the reasons set forth
below, EPA does not believe that the Court's ruling alters any
requirements relevant to this redesignation action so as to preclude
redesignation, and does not prevent EPA from finalizing this
redesignation. EPA believes that the Court's decision, as it currently
stands or as it may be modified based on any petition for rehearing
that has been filed, imposes no impediment to moving forward with
redesignation of this area to attainment, because in either
circumstance redesignation is appropriate under the relevant
redesignation provisions of the CAA and longstanding policies regarding
redesignation requests.

A. Requirements Under the 8-Hour Ozone Standard

    With respect to the 8-hour ozone standard, the Chicago-Gary-Lake
County, IL-IN ozone nonattainment area, which includes Lake and Porter
Counties, is classified as moderate nonattainment under subpart 2. We
do not believe that any part of the Court's opinion would require that
this subpart 2 classification be changed upon remand to EPA. However,
even assuming for present purposes that the Chicago-Gary-Lake County,
IL-IN area would become subject to a different classification scheme
created in a future rule responding to the Court's decision, that would
not prevent EPA from finalizing the redesignation for this area. For
the reasons set forth below, we believe that any additional
requirements that might apply based on a different classification would
not be applicable for purposes of evaluating the 8-hour ozone
redesignation request now before us. This belief is based on: (1) EPA's
longstanding policy of evaluating redesignation requests in accordance
only with the requirements due at the time the redesignation request
was submitted; and (2) consideration of the inequity of applying
retroactively any requirements that might be applied in the future.
    First, at the time the redesignation request was submitted, the
area was classified under subpart 2 and was required to meet the
subpart 2 requirements. Under EPA's longstanding interpretation of
section 107(d)(3)(E) of the CAA, to qualify for redesignation, a state
requesting a redesignation to attainment must meet only the relevant
SIP requirements that came due for the subject area prior to the
submittal of a complete redesignation request. See the September 4,
1992 Calcagni memorandum (``Procedures for Processing Requests to
Redesignate Areas to Attainment,'' Memorandum from John Calcagni,
Director, Air Quality Management Division). See also the September 17,
1993 Shapiro memorandum (``State Implementation Plan (SIP) Requirements
for Areas Submitting Requests for Redesignation to Attainment of the
Ozone and Carbon Monoxide (CO) National Ambient Air Quality Standards
(NAAQS) on or after November 15, 1992,'' Memorandum from Michael H.
Shapiro, Acting Assistant Administrator, Air and Radiation), 60 FR
12459, 12465-66 (March 7, 1995) (redesignation of Detroit-Ann Arbor);
Sierra Club v. EPA, 375 F.3d 537 (7th Cir. 2004), which upheld this
interpretation; 68 FR 25418, 25424, 25427 (May 12, 2003) (redesignation
of St. Louis). At the time the Lake and Porter County redesignation
request was submitted, September 12, 2006, the Chicago-Gary-Lake
County, IL-IN area was not classified under subpart 1 and no subpart 1
requirements were applicable for purposes of redesignation.
    Second, it would be inequitable to retroactively apply any new SIP
requirements that were not applicable at the time the redesignation
request was submitted, but which might later become applicable. The
D.C. Circuit has recognized the inequity in such retroactive
rulemaking. See Sierra Club v. Whitman, 285 F.3d 63 (D.C. Cir. 2002),
in which the D.C. Circuit upheld a District Court's ruling refusing to
make retroactive an EPA determination of nonattainment that was past
the statutory due date. Such a determination would have resulted in the
imposition of additional requirements on the area. The Court stated:
``Although EPA failed to make the nonattainment determination within
the statutory timeframe, Sierra Club's proposed solution only makes the
situation worse. Retroactive relief would likely impose large costs on
the States, which would face fines and suits for not implementing air
pollution prevention plans in 1997, even though they were not on notice
at the time.'' Id. at 68. Similarly, here it would be unfair to
penalize the area by applying to it for purposes of redesignation any
additional requirements under subpart 1 that were not in effect at the
time it submitted its redesignation request, but that might apply in
the future.

B. Requirements Under the 1-Hour Ozone Standard

    In its December 22, 2006 decision in South Coast Air Quality
Management Dist. v. EPA, the Court also addressed EPA's revocation of
the 1-hour ozone standard. The current status of the revocation and
associated anti-backsliding rules is dependent on whether the Court's
decision stands as originally issued or is modified in response to any
petition for rehearing or request for clarification that has been
filed. As described more fully below, EPA believes that the Chicago-
Gary-Lake County, IL-IN area has attained the 1-hour ozone standard and
that the State of Indiana and Lake and Porter Counties have met all of
the requirements applicable for redesignation under the 1-hour ozone
standard that would apply even if the 1-hour ozone standard is deemed
to be reinstated and those requirements are viewed as applying under
the statute itself. Thus, the Court's decision, as it currently stands,
imposes no impediment to moving forward with redesignation of Lake and
Porter Counties to attainment based on the status of the 1-hour ozone
standard. Furthermore, if the 1-hour ozone standard is deemed to be
reinstated, EPA would construe the State's redesignation request under
the 8-hour ozone standard as also constituting a redesignation request
under the 1-hour ozone standard. EPA proposes that, if the 1-hour
standard is deemed to be reinstated, EPA would redesignate Lake and
Porter Counties to attainment of the 1-hour ozone standard because EPA
believes that the area has satisfied all of the 1-hour requirements for
such redesignation, as explained in the analysis below. Further, even
if the Court's decision were modified based on any petition for
rehearing that has been filed such that the ultimate decision requires
something less than compliance with all applicable 1-hour ozone
requirements, this would not pose an impediment to redesignating the
area to attainment of the 1-hour ozone standard. Since the area meets
all current 1-hour ozone requirements as explained below, it would
certainly meet any lesser requirements and, thus similarly,
redesignation could proceed.

IV. What Are the Criteria for Redesignation to Attainment of the 8-Hour
Ozone NAAQS?

    The CAA provides the basic requirements for redesignating a
nonattainment area to attainment. Specifically, section 107(d)(3)(E) of
the CAA authorizes redesignation provided that: (1) The Administrator
determines that the area has attained the applicable NAAQS based on
current air quality data; (2) the Administrator has fully approved an
applicable state implementation plan for the area under section 110(k)
of the CAA; (3) the Administrator determines that the improvement in
air quality is due to permanent and enforceable emission reductions
resulting from implementation of the applicable SIP, Federal air
pollution control regulations, and other permanent and enforceable
emission reductions; (4) the Administrator has fully approved a
maintenance plan for the area meeting the requirements of section 175A
of the CAA; and, (5) the state containing the area has met all
requirements applicable to the area under section 110 and part D of the
CAA.
    EPA provided guidance on redesignations in the General Preamble for
the Implementation of Title I of the CAA Amendments of 1990 on April
16, 1992 (57 FR 13498), and supplemented this guidance on April 28,
1992 (57 FR 18070). Two significant policy guidance documents affecting
the review of ozone redesignation requests are the following:
``Procedures for Processing Requests to Redesignate Areas to
Attainment,'' Memorandum from John Calcagni, Director, Air Quality
Management Division, September 4, 1992 (the September 4, 1992 Calcagni
memorandum); and, ``Reasonable Further Progress, Attainment
Demonstration, and Related Requirements for Ozone Nonattainment Areas
Meeting the Ozone National Ambient Air Quality Standard,'' Memorandum
from John S. Seitz, Director, Office of Air Quality Planning and
Standards, May 10, 1995 (the May 10, 1995 Clean Data Policy
memorandum). For additional policy guidance used in the review of ozone
redesignation requests, see our proposed rule for the redesignation of
the Evansville, Indiana ozone nonattainment area at 70 FR 53606
(September 9, 2005).

V. What Are EPA's Analyses of the State's Redesignation Request and
Maintenance Plan and What Are the Bases for EPA's Proposed Action?

    EPA is proposing to: (1) Determine that Lake and Porter Counties
and the Chicago-Gary-Lake County, IL-IN area have attained the 8-hour
ozone standard and the 1-hour ozone standard; (2) approve the ozone
maintenance plan for Lake and Porter Counties and the VOC and
NOX MVEBs supported by the maintenance plan; and, (3)
approve the redesignation of Lake and Porter Counties to attainment of
the 8-hour ozone NAAQS and to attainment of the 1-hour ozone NAAQS, if
it is deemed to be reinstated. The bases for our proposed determination
and approvals follow.

A. Have Lake and Porter Counties and the Entire Chicago-Gary-Lake
County, IL-IN Nonattainment Area Attained the 8-Hour Ozone NAAQS and
the 1-Hour Ozone NAAQS?

1. Attainment of the 8-Hour Ozone NAAQS
    For ozone, an area may be considered to be attaining the 8-hour
ozone NAAQS if there are no violations of the NAAQS, as determined in
accordance with 40 CFR 50.10 and appendix I, based on the most recent
three complete, consecutive calendar years of quality-assured air
quality monitoring data at all ozone monitoring sites in the area and
at any monitor used to calculate its design value. To attain this
standard, the average of the annual fourth-high daily maximum 8-hour
average ozone concentrations measured and recorded at each monitor (the
monitoring site's ozone design value) within the area and used to
calculate its design value, over the most recent three-year period must
not exceed the ozone standard. Based on an ozone data rounding
convention described in 40 CFR 50, appendix I, the 8-hour ozone
standard is attained if the area's ozone design value \5\ is 0.084 ppm
(84 ppb) or less. The data must be collected and quality-assured in
accordance with 40 CFR 58, and is recorded in EPA's Air Quality System
(AQS). The ozone monitors generally should have remained at the same
locations for the duration of the monitoring period required to
demonstrate attainment (for three years or more). The data supporting
attainment of the standard must be complete in accordance with 40 CFR
50, appendix I.
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    \5\ The worst-case monitoring site-specific ozone design value
in the area and in its nearby downwind environs.
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    At the time of the September 12, 2006 ozone redesignation request,
preliminary 8-hour ozone monitoring data for Lake and Porter Counties
and for the Illinois portion of the Chicago-Gary-Lake County, IL-IN
nonattainment area showed that the area was attaining the standard for
2004-2006, and that the 2006 4th high 8-hour daily average
concentration was 0.081 ppm. Since the submittal of the redesignation
request, Indiana and other States in the Lake Michigan area have
submitted quality-assured data for 2006 to the AQS. Table 1 summarizes
the annual fourth-high 8-hour ozone concentrations during the

period of 2004-2006, the most recent three years of available quality-
assured ozone data, for all monitors in the Chicago-Gary-Lake County,
IL-IN area and for the Chiwaukee Prairie monitoring site in Wisconsin,
the critical ozone design value site for the Chicago-Gary-Lake County,
IL-IN ozone nonattainment area.

Table 1.--Annual Fourth-High Daily Maximum 8-Hour Ozone Concentrations in Parts per Million (ppm) and Three-Year
                                                    Averages
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                                                                         Percent        Fourth-high      Three-
       Site ID              County         Address/site      Year     observations     daily maximum      year
                                                                      ozone season     concentration    average
----------------------------------------------------------------------------------------------------------------
                                            INDIANA MONITORING SITES
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18-089-002...........  Lake............  Gary...........       2004             100             0.064         NA
                                         Gary...........       2005              96             0.089         NA
                                         Gary...........       2006              98             0.073      0.075
18-089-2008..........  Lake............  Hammond........       2004             100             0.067         NA
                                         Hammond........       2005              99             0.087         NA
                                         Hammond........       2006             100             0.075      0.076
18-127-0024..........  Porter..........  Ogden Dunes....       2004             100             0.069         NA
                                         Ogden Dunes....       2005              99             0.090         NA
                                         Ogden Dunes....       2006             100             0.070      0.076
18-127-0026..........  Porter..........  Valparaiso.....       2004             100             0.072         NA
                                         Valparaiso.....       2005             100             0.078         NA
                                         Valparaiso.....       2006              99             0.071      0.073
----------------------------------------------------------------------------------------------------------------
                                            ILLINOIS MONITORING SITES
----------------------------------------------------------------------------------------------------------------
17-031-0001..........  Cook............  Alsip..........       2004             100             0.065         NA
                                         Alsip..........       2005             100             0.084         NA
                                         Alsip..........       2006             100             0.078      0.075
17-031-0032..........  Cook............  Chicago-              2004             100             0.067         NA
                                          Cheltenham.
                                         Chicago-              2005             100             0.076         NA
                                          Cheltenham.
                                         Chicago-              2006             100             0.075      0.072
                                          Cheltenham.
17-031-0042..........  Cook............  Wacker at Adams       2004              64             0.069         NA
                                         Wacker at Adams       2005              51             0.080         NA
                                         Wacker at Adams       2006              85             0.072      0.073
17-031-0064..........  Cook............  Chicago-Ellis         2004             100             0.054         NA
                                          Ave..
                                         Chicago-Ellis         2005             100             0.084         NA
                                          Ave..
                                         Chicago-Ellis         2006              99             0.070      0.069
                                          Ave..
17-031-0072..........  Cook............  Chicago-Ohio          2004              98             0.060         NA
                                          Street.
                                         Chicago-Ohio          2005              99             0.081         NA
                                          Street.
                                         Chicago-Ohio          2006             100             0.065      0.068
                                          Street.
17-031-0076..........  Cook............  Chicago-              2004             100             0.068         NA
                                          Lawndale.
                                         Chicago-              2005             100             0.084         NA
                                          Lawndale.
                                         Chicago-              2006             100             0.075      0.075
                                          Lawndale.
17-031-1003..........  Cook............  Chicago-Hurlbut       2004              99             0.067         NA
                                          St..
                                         Chicago-Hurlbut       2005              99             0.083         NA
                                          St..
                                         Chicago-Hurlbut       2006              95             0.075      0.075
                                          St..
17-031-1601..........  Cook............  Lemont.........       2004              94             0.067         NA
                                         Lemont.........       2005             100             0.086         NA
                                         Lemont.........       2006              96             0.070      0.074
17-031-4002..........  Cook............  Cicero.........       2004             100             0.059         NA
                                         Cicero.........       2005             100             0.075         NA
                                         Cicero.........       2006             100             0.060      0.064
17-031-4007..........  Cook............  Des Plaines....       2004              94             0.064         NA
                                         Des Plaines....       2005              99             0.079         NA
                                         Des Plaines....       2006             100             0.065      0.069
17-031-4201..........  Cook............  Northbrook.....       2004              97             0.067         NA
                                         Northbrook.....       2005             100             0.081         NA
                                         Northbrook.....       2006             100             0.068      0.072
17-031-7002..........  Cook............  Evanston.......       2004             100             0.074         NA
                                         Evanston.......       2005              98             0.082         NA
                                         Evanston.......       2006              97             0.072      0.076
17-043-6001..........  DuPage..........  Lisle..........       2004              99             0.065         NA
                                         Lisle..........       2005              97             0.078         NA
                                         Lisle..........       2006             100             0.062      0.068
17-089-0005..........  Kane............  Elgin..........       2004              99             0.067         NA
                                         Elgin..........       2005             100             0.086         NA
                                         Elgin..........       2006              84             0.062      0.071
17-097-1002..........  Lake............  Waukegan.......       2004             100             0.067         NA
                                         Waukegan.......       2005              99             0.087         NA
                                         Waukegan.......       2006             100             0.071      0.075
17-097-1007..........  Lake............  IL Beach State        2004              99             0.071         NA
                                          Park.
                                         IL Beach State        2005              98             0.090         NA
                                          Park.
                                         IL Beach State        2006             100             0.068      0.076
                                          Park.

17-111-0001..........  McHenry.........  Cary...........       2004             100             0.068         NA
                                         Cary...........       2005              98             0.087         NA
                                         Cary...........       2006             100             0.057      0.070
17-197-1011..........  Will............  Essex Road.....       2004              99             0.067         NA
                                         Essex Road.....       2005             100             0.077         NA
                                         Essex Road.....       2006              94             0.068      0.070
----------------------------------------------------------------------------------------------------------------
                                            WISCONSIN MONITORING SITE
----------------------------------------------------------------------------------------------------------------
55-059-0019..........  Kenosha.........  Chiwaukee             2004             100             0.078         NA
                                          Prairie.
                                         Chiwaukee             2005              98             0.093         NA
                                          Prairie.
                                         Chiwaukee             2006              99             0.079      0.083
                                          Prairie.
----------------------------------------------------------------------------------------------------------------

    Please note that site 17-031-0042 is located on the top of the
Sears Tower, in excess of 1,000 feet above ground-level. This is a
special purpose monitor that is not intended to measure ambient air
concentrations (concentrations collected near nose levels of adults in
areas where the public generally has access). As such, the lack of data
during the ozone seasons for this site does not constitute a data
completeness problem.
    Review of the 2004-2006 ozone concentrations summarized in Table 1
shows that all of the ozone monitoring sites in the Chicago-Gary-Lake
County, IL-IN ozone nonattainment area, as well as the Chiwaukee
Prairie ozone monitoring site, attained the 8-hour ozone standard
during this period. Therefore, based on the most recent three years of
quality-assured ozone monitoring data, the 8-hour ozone NAAQS has been
attained in the Chicago-Gary-Lake County, IL-IN area.
2. Attainment of the 1-Hour Ozone NAAQS
    Prior to the revocation of the 1-hour ozone standard, the Chicago-
Gary-Lake County IL-IN area was designated a severe nonattainment area
under the 1-hour standard. If the 1-hour NAAQS is deemed reinstated,
EPA would construe the State's request for redesignation under the 8-
hour standard as also constituting a request under the 1-hour standard.
To support a possible redesignation to attainment for Lake and Porter
Counties to attainment of the 1-hour ozone NAAQS, if the 1-hour NAAQS
is deemed reinstated, it must be shown that the Chicago-Gary-Lake
County, IL-IN area is attaining the 1-hour ozone NAAQS. An area is
considered attaining the 1-hour ozone NAAQS if there are no violations,
as determined in accordance with the regulation codified at 40 CFR
50.9, based on three consecutive calendar years of complete, quality-
assured monitoring data. A violation occurs when the ozone air quality
monitoring data show greater than one (1.0) average expected exceedance
per year at any site in the area. An exceedance occurs when the maximum
hourly ozone concentration exceeds 0.124 parts per million (ppm). The
data should be collected and quality-assured in accordance with 40 CFR
part 58, and recorded in the AQS so that it is available to the public
for review.
    The Indiana request is based on an analysis of ozone air quality
data from 2004-2006. Table 2 below summarizes this air quality data.

Table 2.--1-Hour Ozone Exceedances at Monitoring Sites in the Chicago-Gary-Lake County, IL-IN Area Including the
                                  Chiwaukee Prairie Monitoring Site (2004-2006)
----------------------------------------------------------------------------------------------------------------
                                                            No. 2004      No. 2005      No. 2006     3-year avg.
      Site code             County             Site        exceedances   exceedances   exceedances   exceedances
----------------------------------------------------------------------------------------------------------------
                                                    ILLINOIS
----------------------------------------------------------------------------------------------------------------
17-031-0001..........  Cook............  Alsip..........           0.0           1.0           0.0           0.3
17-031-0076..........  Cook............  Chicago-Com Ed.           0.0           0.0           0.0           0.0
17-031-0072..........  Cook............  Chicago-Jardine           0.0           0.0           0.0           0.0
17-031-0032..........  Cook............  Chicago-SWFP...           0.0           1.0           0.0           0.3
17-031-1003..........  Cook............  Chicago-Taft...           0.0           0.0           0.0           0.0
17-031-0064..........  Cook............  Chicago-                  0.0           0.0           0.0           0.0
                                          University.
17-031-4002..........  Cook............  Cicero.........           0.0           0.0           0.0           0.0
17-031-4007..........  Cook............  Des Plaines....           0.0           0.0           0.0           0.0
17-031-7002..........  Cook............  Evanston.......           0.0           0.0           0.0           0.0
17-031-1601..........  Cook............  Lemont.........           0.0           0.0           0.0           0.0
17-031-4201..........  Cook............  Northbrook.....           0.0           0.0           0.0           0.0
17-043-6001..........  DuPage..........  Lisle..........           0.0           0.0           0.0           0.0
17-089-0005..........  Kane............  Elgin..........           0.0           0.0           0.0           0.0
17-097-1002..........  Lake............  Waukegan.......           0.0           0.0           0.0           0.0
17-097-1007..........  Lake............  Zion...........           0.0           0.0           0.0           0.0
17-111-0001..........  McHenry.........  Cary...........           0.0           0.0           0.0           0.0
17-197-1011..........  Will............  Braidwood......           0.0           0.0           0.0           0.0
----------------------------------------------------------------------------------------------------------------
                                                     INDIANA
----------------------------------------------------------------------------------------------------------------
18-089-0022..........  Lake............  Gary...........           0.0           1.0           0.0           0.3

18-089-2008..........  Lake............  Hammond........           0.0           0.0           0.0           0.0
18-089-0030..........  Lake............  Whiting........           0.0           0.0           0.0           0.0
18-127-0024..........  Porter..........  Ogden Dunes....           0.0           1.0           0.0           0.3
18-127-0026..........  Porter..........  Valparaiso.....           0.0           0.0           0.0           0.0
----------------------------------------------------------------------------------------------------------------
                                                    WISCONSIN
----------------------------------------------------------------------------------------------------------------
55-059-0019..........  Kenosha.........  Chiwaukee                 0.0           0.0           0.0           0.0
                                          Prairie.
----------------------------------------------------------------------------------------------------------------

    From Table 2, it can be seen that the Chicago-Gary-Lake County, IL-
IN area is attaining the 1-hour ozone standard for the 2004-2006 period
because there were no average expected exceedances greater than 1.0.

B. Has the State of Indiana Committed To Maintain the Ozone Monitoring
System in Lake and Porter Counties?

    IDEM commits to maintain the ozone monitoring system in Lake and
Porter Counties during the maintenance period. Any necessary changes in
the ozone monitoring system will be discussed in advance with the EPA.
Therefore, the State of Indiana meets a redesignation condition that we
normally require of States seeking redesignation of areas to attainment
of the ozone standard.

C. Have Lake and Porter Counties and the State of Indiana Met All of
the Requirements of Section 110 and Part D of the CAA Applicable for
Purposes of Redesignation, and Do Lake and Porter Counties Have a Fully
Approved SIP Under Section 110(k) of the CAA for Purposes of
Redesignation to Attainment?

    We have determined that Lake and Porter Counties and the State of
Indiana have met all SIP requirements currently applicable for purposes
of redesignation to attainment of the 8-hour NAAQS for this area under
section 110 of the CAA (general SIP requirements). We have also
determined that Indiana has met the SIP requirements applicable for
purposes of redesignation under subpart 2 part D of title I of the CAA
(requirements specific to ozone nonattainment areas classified under
subpart 2. See section 107(d)(3)(E)(v) of the CAA. In addition, we have
determined that all applicable requirements, with the exception of the
base year emissions inventory, are approved in the Indiana SIP. As
discussed in section VIII, below, as part of today's action, EPA is
proposing to approve Indiana's 2002 base year emissions inventory. See
section 107(d)(3)(E)(ii) of the CAA. In making these determinations, we
reviewed the CAA requirements which are applicable to Lake and Porter
Counties for purposes of redesignation, and concluded that the
applicable portions of the SIP meeting these requirements are fully
approved under section 110(k) of the CAA. We note that SIPs must be
fully approved only with respect to currently applicable requirements
of the CAA, which in this case are those CAA requirements applicable to
Lake and Porter Counties at the time the State submitted a complete
ozone redesignation request for this area, on September 12, 2006.
1. Lake and Porter Counties Have Met All Requirements of Section 110
and Part D of the CAA Applicable for Purposes of Redesignation for the
8-Hour NAAQS
    The September 4, 1992 Calcagni memorandum describes EPA's
interpretation of section 107(d)(3)(E) of the CAA. Under this
interpretation, to qualify for redesignation of an area to attainment,
the State and the area must meet the relevant CAA requirements that
come due prior to the State's submittal of a complete redesignation
request for the area. See also a September 17, 1993 memorandum from
Michael Shapiro, Acting Assistant Administrator for Air and Radiation,
subject ``State Implementation Plan (SIP) Requirements for Areas
Submitting Requests for Redesignation to Attainment of the Ozone and
Carbon Monoxide (CO) National Ambient Air Quality Standards (NAAQS) On
or After November 15, 1992'' and 66 FR 12459, 12465-12466 (March 7,
1995) redesignation of Detroit-Ann Arbor, Michigan to attainment of the
1-hour ozone NAAQS. Applicable requirements of the CAA that come due
subsequent to the State's submittal of a complete redesignation request
remain applicable until a redesignation to attainment of an area is
approved, but are not required as a prerequisite to redesignation. See
section 175A(c) of the CAA. Sierra Club v. EPA, 375 F.3d 537 (7th Cir.
2004). See also 68 FR 25424, 25427 (May 12, 2003) (redesignation of the
St. Louis/East St. Louis area to attainment of the 1-hour ozone NAAQS).
a. Section 110 and General SIP Requirements
    Section 110(a) of title I of the CAA contains the general
requirements for a SIP, which include: Enforceable emission limitations
and other control measures, means, or techniques; provisions for the
establishment and operation of appropriate devices necessary to collect
data on ambient air quality; and programs to enforce the emission
limitations. General SIP elements and requirements are specified in
section 110(a)(2) of title I, part A of the CAA. These requirements and
SIP elements include, but are not limited to, the following: (i)
Submittal of a SIP that has been adopted by the State after reasonable
public notice and a public hearing; (ii) provisions for establishment
and operation of appropriate procedures needed to monitor ambient air
quality; (iii) provisions for implementation of a source permit
program; (iv) provisions for implementation of new source part C
requirements (Prevention of Significant Deterioration (PSD)) and new
source part D requirements (NSR); (v) criteria for stationary source
emission control measures, monitoring, and reporting; (vi) provisions
for air quality modeling; and, (vii) provision for public and local
agency participation.
    SIP requirements and elements are discussed in the following EPA
documents: The September 4, 1992 Calcagni memorandum; and, the
September 17, 1993 Shapiro memorandum. See also other guidance
documents discussed above.
    Section 110(a)(2)(D) of the CAA requires SIPs to contain certain
measures to prevent sources in one state from significantly
contributing to air

quality problems in another state. However, the section 110(a)(2)(D)
requirements for a state are not linked with a particular nonattainment
area's classification. EPA believes that the requirements linked with a
particular nonattainment area's classification are the relevant
measures to evaluate when reviewing a redesignation request. The
transport SIP submittal requirements, where applicable, continue to
apply to a state regardless of the designation of any one particular
area in the State.
    We believe that these requirements should not be construed to be
applicable requirements for purposes of redesignation. 65 FR 37890
(June 19, 2000), 66 FR 50399 (October 19, 2001), 68 FR 25418, 25426-27
(May 13, 2003). Further, we believe that the other section 110 elements
described above that are not connected with nonattainment plan
submissions and that are not linked with an area's attainment status
are also not applicable requirements for purposes of redesignation. A
state remains subject to these requirements after an area is
redesignated to attainment. We conclude that only the section 110 and
part D requirements which are linked with an area's designation and
classification are the relevant measures for evaluating this aspect of
a redesignation request. This approach is consistent with EPA's policy
on applicability of conformity and oxygenated fuels requirements for
redesignation purposes, as well as with section 184 ozone transport
control requirements. See: Reading, Pennsylvania proposed and final
rulemakings (61 FR 53174-53176, October 10, 1996 and 62 FR 24826, May
7, 1997); Cleveland-Akron-Lorain, Ohio final rulemaking (61 FR 20458,
May 7, 1996); and Tampa, Florida final rulemaking (60 FR 62748,
December 7, 1995). See also the discussion on this issue in the
Cincinnati, Ohio ozone redesignation (65 FR 37890, June 19, 2000), and
the Pittsburgh, Pennsylvania ozone redesignation (66 FR 50399, October
19, 2001).
    We believe that section 110 elements not linked to the area's
nonattainment status are not applicable for purposes of redesignation.
Any section 110 requirements that are linked to the Part D requirements
for 8-hour ozone nonattainment areas are not yet due, because, as noted
below, the only Part D requirements applicable for purposes of
redesignation under the 8-hour standard that have become due are the
emissions inventory and emissions statement. Therefore EPA concludes
that Indiana has satisfied the criterion of section 107(d)(3)(E)
regarding section 110 of the Act.
    Nonetheless, we also note that the EPA has previously approved
provisions in the Indiana SIP addressing section 110 elements under the
1-hour ozone standard.
b. Part D SIP Requirements Under the 8-Hour Ozone Standard
    EPA has determined that the Indiana SIP, with the approval of the
base year emissions inventory, will meet applicable SIP requirements
under part D of the CAA as they apply to redesignation to attainment of
the 8-hour ozone NAAQS. Under part D, an area's classification
indicates the requirements to which it will be subject. Subpart 1 of
part D, which includes sections 172-176 of the CAA, sets forth the
basic nonattainment area plan requirements applicable to all
nonattainment areas. Subpart 2 of part D, which includes section 182 of
the CAA, establishes additional, specific requirements for ozone
nonattainment areas dependent on an area's nonattainment
classification.
    The subpart 1 requirements for all nonattainment areas are
contained in sections 172(c)(1-9) and section 176. A thorough
discussion of the requirements of section 172 can be found in the
General Preamble for Implementation of Title I (57 FR 13498).
    The SIP requirements of subpart 2 which are relevant to the review
of Indiana's ozone redesignation request are contained in sections
182(a) (marginal nonattainment area requirements) and 182(b) (moderate
nonattainment area requirements) of the CAA.\6\ As noted in our
discussion of 1-hour nonattainment requirements, below, as part of a
severe 1-hour ozone nonattainment area, the State of Indiana and Lake
and Porter Counties had previously been subject to the requirements of
sections 182(a), 182(b), and 182(c) and 182(d) of the CAA.\7\
---------------------------------------------------------------------------

    \6\ As a part of a moderate nonattainment area for the 8-hour
ozone NAAQS, Lake and Porter Counties are subject to requirements
for both moderate nonattainment areas and marginal nonattainment
areas because the requirements of section 182 are cumulative. Under
this section, nonattainment areas are subject to all requirements at
their classification level and all requirements for areas of lower
classification.
    \7\ As a severe nonattainment area under the 1-hour ozone NAAQS,
Lake and Porter Counties had to comply with requirements for severe
ozone nonattainment areas.
---------------------------------------------------------------------------

    As a moderate nonattainment area under the 8-hour ozone NAAQS, the
Chicago-Gary-Lake County nonattainment area was subject to subpart 2
requirements for moderate nonattainment areas. Only two ``new''
requirements for moderate nonattainment areas under the 8-hour ozone
NAAQS came due prior to Indiana's September 12, 2006 submittal of the
complete redesignation request for Lake and Porter Counties. One such
requirement is that the State submit a 2002 base year comprehensive,
accurate inventory of actual emissions of VOC and NOX in
Lake and Porter Counties in compliance with section 182(a)(1) of the
CAA. This requirement came due on June 15, 2006, prior to submission of
the area's redesignation request. 70 FR 71612, 71664 (November 29,
2005) 40 CFR section 5.915. On March 26, 2007, IDEM submitted
documentation of 2002 base year VOC and NOX emissions in
every county in the State. The base year emissions documentation for
Lake and Porter Counties is reviewed below in section VIII of this
proposed rule. EPA proposes to conclude that Indiana has complied with
this requirement.
    A second requirement which came due on June 15, 2006 is a
requirement under section 182(a)(3)(B) of the CAA for State rules
requiring major stationary sources to annually report facility
emissions of VOC and NOX (annual emission statements).
Indiana revised its State rule regarding emission statements under the
8-hour ozone standard, and we approved this rule on March 29, 2007 (72
FR 14678).
    We believe that other requirements under subparts 1 and 2 that
apply to Lake and Porter Counties did not come due prior to the State's
submittal of a complete ozone redesignation request for this area and
thus do not apply to an evaluation of the redesignation request. Under
EPA's longstanding policy these requirements are not applicable for
purposes of redesignation. See September 4, 1992 Calcagni memorandum,
Detroit-Ann Arbor redesignation, 60 FR 12459, 12465-66 (March 7, 1995),
and Sierra Club v. EPA, 375 F.3d 537 (7th Cir. 2004).
    For example, the requirement for submission of an ozone attainment
demonstration as contained in section 172(c)(1) was not yet applicable
for this area, nor was the requirement for contingency measures under
section 172(c)(9) and 182(c)(9), both of which were not due until June
15, 2007.
    In addition, no section 172(c)(1) and 182(b)(2) RACT requirement
submission under the 8-hour standard is applicable for purposes of
redesignation, since the State submitted a redesignation request on
September 12, 2006, prior to the due date of the RACT requirements.
Thus because the RACT requirements did not become due until after
September 15, 2006, under EPA's longstanding policy

these requirements are not applicable for purposes of redesignation.
Preliminary monitoring data through the time of submittal of the
redesignation request showed that the area was attaining the standard,
and quality-assured data subsequently showed that the area continued to
attain the standard through the end of the ozone season. In addition,
the fourth-high concentration for all monitoring sites had occurred by
mid-July, 2006. The State of Indiana was tracking peak ozone
concentrations in 2006, and through the near-realtime AIRNOW public
information system; so was EPA. EPA and the State were aware of the
fact that the likely high ozone concentrations in 2006 had occurred
prior to the State's submittal of the redesignation request. After
reviewing the peak 8-hour ozone concentrations in 2006, we found that
the top four 8-hour ozone concentrations for all monitoring sites in
the Chicago-Gary-Lake County, IL-IN area and the Chiwaukee Prairie site
during 2006 occurred well prior to September 12. In recent previous
years as well, no fourth high concentration in excess of the standard
had occurred after September 12, and values monitored in late September
were below the standard. In 2004-2006, no values above 85 ppm were
recorded after September 12. Given the fact that peak ozone
concentrations in this area usually occur in June, July, and August, it
was highly unlikely at the time of submittal that any additional
exceedances would occur after submittal of the redesignation request,
and quality-assured data showed that none did in fact occur.
    Moreover, with respect to conformity and NSR requirements, EPA
believes that these are not applicable requirements for purposes of
evaluating a redesignation request.
    Under Section 176(c), the CAA requires states to establish criteria
and procedures to ensure that Federally-supported or funded activities,
including highway projects, conform to the air planning goals in the
applicable SIPs. The requirement to determine conformity applies to
transportation plans, programs, and projects developed, funded, or
approved under Title 23 U.S.C. and the Federal Transit Act
(transportation conformity) as well as to all other Federally-supported
or funded projects (general conformity). State conformity SIP revisions
must be consistent with Federal conformity regulations that EPA issued
pursuant to the CAA. EPA's longstanding interpretation is that
conformity requirements are not applicable requirements for purposes of
evaluating redesignation requests. State conformity rules are still
required after redesignation of areas to attainment of a NAAQS, and
Federal conformity rules apply where state rules have not been
approved. See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001). See also 60 FR
62748 (December 7, 1995) (Tampa, Florida).
    EPA has also determined that areas being redesignated need not
comply with the requirement that a NSR program be approved prior to
redesignation (although Indiana does have an approved NSR program),
provided that the states demonstrate maintenance of the standard
without part D NSR. PSD requirements will apply after redesignations to
attainment. A more detailed rationale for this view is described in a
memorandum from Mary Nichols, Assistant Administrator for Air and
Radiation, dated October 14, 1994, entitled, ``Part D New Source Review
Requirements for Areas Requesting Redesignation to Attainment.''
Indiana has demonstrated that Lake and Porter Counties and the Chicago-
Gary-Lake County, IL-IN area will be able to maintain the 8-hour ozone
standard without part D NSR in effect, and therefore, we conclude that
the State need not have a fully approved part D NSR program prior to
approval of the redesignation request. The State's PSD program will
become effective in Lake and Porter Counties upon redesignation to
attainment. See rulemakings for: Detroit, Michigan (60 FR 12467-12468,
March 7, 1995); Cleveland-Akron-Lorain, Ohio (61 FR 20458, 20469-20470,
May 7, 1996); Louisville, Kentucky (66 FR 53665, October 23, 2001);
and, Grand Rapids, Michigan (61 FR 31834-31837, June 21, 1996).
2. Lake and Porter Counties Have a Fully Approved SIP Under Section
110(k) of the CAA
    Except as noted above with respect to emissions inventories, EPA
has fully approved the Indiana SIP for Lake and Porter Counties under
section 110(k) of the CAA for all requirements applicable for purposes
of redesignation. EPA may rely on prior SIP approvals in approving a
redesignation request (See the September 4, 1992 John Calcagni
memorandum, page 3, Southwestern Pennsylvania Growth Alliance v.
Browner, 144 F.3d 984, 989-990 (6th Cir. 1998), and Wall v. EPA, 265
F.3d 426 (6th Cir. 2001)) plus any additional measures it may approve
in conjunction with a redesignation action. See 68 FR 25426 (May 12,
2003). Indiana has adopted and submitted, and EPA has fully approved at
various times, provisions addressing the various 1-hour required SIP
elements applicable to Lake and Porter Counties for purposes of
redesignation, as well as the emissions statement provision for the 8-
hour standard. As indicated above, EPA believes that the section 110
elements not connected with nonattainment plan submissions and not
linked to the area's nonattainment status are not applicable
requirements for purposes of reviewing the State's redesignation
request. EPA also believes that since the part D 8-hour requirements,
(with the exception of the requirements for submittal of the emissions
statement, and the requirement for submittal of a base year emissions
inventory, which we address here, including documentation of the base
year emissions supplied by the State subsequent to the submittal of the
ozone redesignation request), did not become due prior to Indiana's
submission of a final, complete redesignation request for Lake and
Porter Counties, they also are not applicable requirements for purposes
of redesignation.

D. Have Lake and Porter Counties Met the Part D Nonattainment Area and
Section 110 Requirements Under the 1-Hour Ozone Standard?

    In this section of the proposed rule, we discuss the 1-hour ozone
SIP emission control requirements of the CAA applicable to Lake and
Porter Counties. As noted above, prior to the revocation of the 1-hour
ozone standard, the Chicago-Gary-Lake County, IL-IN area was a severe
nonattainment area under the 1-hour ozone standard. In reviewing the
State of Indiana's ozone redesignation request for Lake and Porter
Counties, we assessed the compliance of this area with the CAA
requirements under the 1-hour ozone standard. If the 1-hour standard is
deemed to be reinstated, EPA would construe the State's request for
redesignation under the 8-hour standard as also constituting a request
under the 1-hour standard. We conclude that Lake and Porter Counties
and the State have met all CAA requirements applicable to a severe 1-
hour ozone nonattainment area.
    Lake and Porter Counties, as part of the Chicago-Gary-Lake County,
IL-IN area, were subject to ozone requirements for severe 1-hour ozone
nonattainment areas pursuant to sections 182(a) through 182(d) of the
CAA.
    The following paragraphs discuss how the applicable requirements
have been met, if the 1-hour standard is deemed to be reinstated.

RACT
    Section 182(a)(2)(A) requires RACT corrections, Section 182(b)(2)
of the CAA requires RACT for each category of VOC sources covered by a
Control Technique Guideline (CTG) and for all other major sources of
VOC within an ozone nonattainment area, and Section 182(d) specifies
requirements for severe areas, including a major source cutoff of 25
tons per year. Section 182(f) of the CAA requires major sources of
NOX in an ozone nonattainment area to be covered by the same
types of emission controls required for sources of VOC, or, in other
words, it requires NOX RACT. Through rulemakings on: March
6, 1992 (57 FR 8082); May 4, 1995 (60 FR 22240); July 5, 1995 (60 FR
34856); January 17, 1997 (62 FR 2591 and 62 FR 2593); October 30, 1996
(61 FR 55889); June 29, 1998 (63 FR 35141); and, June 8, 2000 (65 FR
36343), EPA fully approved Indiana's VOC RACT regulation SIP revisions
for Control Technique Guideline (CTG) sources and for non-CTG sources
which have an applicability threshold of 25 tons per year (tpy) or
more. On January 26, 1996 (61 FR 2428), EPA approved a NOX
control waiver request under section 182(f) of the CAA, exempting Lake
and Porter Counties from the NOX RACT requirement of section
182(f) as it applied to the 1-hour ozone NAAQS.
NSR
    Section 182(a)(2)(C) requires States to adopt an NSR permit program
and to correct the existing NSR permit programs to meet EPA NSR
guidelines issued prior to 1990. EPA approved Indiana's NSR permit
program, including the requirements in section 182(c)(6), (c)(7) and
(c)(8), and the offset requirements in section 182(d)(2) through
rulemakings on October 7, 1994 (59 FR 51108), August 18, 1995 (60 FR
43008), and July 21, 1997 (62 FR 38919). Moreover, as noted above, EPA
believes that these are not applicable requirements for purposes of
evaluating a redesignation request.
Major Source Emission Statements
    Section 182(a)(3)(B) of the CAA requires States to adopt rules
requiring major sources of VOC and NOX in an ozone
nonattainment area to submit annual emissions statements regarding
their emissions for the prior years. Through rulemakings on August 9,
1994 (59 FR 29956) and October 29, 2004 (69 FR 63069), EPA approved
Indiana's emissions statements regulations for 1-hour ozone
nonattainment areas.
Vehicle I/M
    Through rulemakings on March 19, 1996 (61 FR 11142) and September
27, 2001 (66 FR 49297), EPA fully approved Indiana's vehicle I/M
program as meeting the enhanced program requirements of section
182(c)(3) of the CAA. Therefore, Lake and Porter Counties meet the I/M
requirements for a severe 1-hour ozone nonattainment area.
ROP
    Sections 182(b)(1)(A) and 182(c)(2)(B) of the CAA establish the ROP
requirements for ozone nonattainment areas. EPA has fully approved
Indiana's SIP revisions that demonstrate that Indiana has achieved ROP
in Lake and Porter Counties. On July 18, 1997 (62 FR 38457), EPA
approved Indiana's plan to achieve a 15 percent reduction in VOC
emissions in Lake and Porter Counties that was required in section
182(b) of the CAA. On January 26, 2000 (65 FR 4126), EPA approved
Indiana's plan to achieve ROP between 1996 and 1999 in Lake and Porter
Counties, meeting the ROP requirements of section 182(c) of the CAA.
Finally, on November 13, 2001 (66 FR 56944), EPA approved Indiana's
plan to achieve ROP emission reductions from 1999 through 2007.
Stage II Gasoline Vapor Recovery
    On November 3, 1999 (64 FR 59642), EPA approved Indiana's Stage II
gasoline vapor recovery program for Lake and Porter Counties as
required by section 182(b)(2) of the CAA.
Clean Fuel Fleet Program
    On March 21, 1996 (61 FR 11552), EPA approved Indiana's clean fuel
fleet program rules as required by section 182(c)(4) of the CAA.
Conformity
    The conformity portion of the Court's ruling in South Coast Air
Quality Management District v. EPA does not impact the redesignation
request for Lake and Porter Counties because there are no conformity
requirements that are relevant to redesignation requests for any
standard, including the requirement to submit a transportation
conformity SIP.\8\ Under longstanding EPA policy, EPA believes it is
reasonable to interpret the conformity SIP requirements as not applying
for purposes of evaluating a redesignation request under section 107(d)
because State conformity rules are still required after redesignation
and Federal conformity rules apply where State rules have not been
approved. See 40 CFR 51.390. Also see Wall v. EPA, 265 F.3d 426 (6th
Cir. 2001), upholding this interpretation, and 60 FR 62748 (December 7,
1995) (Tampa, Florida ozone redesignation).
---------------------------------------------------------------------------

    \8\ CAA section 176(c)(4)(E) requires States to submit revisions
to their SIPs to reflect certain Federal criteria and procedures for
determining transportation conformity. Transportation conformity
SIPs are different from motor vehicle emissions budgets that are
established in control strategy SIPs and maintenance plans.
---------------------------------------------------------------------------

Section 185 Fee Provisions
    Although the fees provision under section 185(a) of the CAA was not
specifically identified in the May 10, 1995 Clean Data Policy
memorandum as one of the requirements subject to EPA's Clean Data
Policy interpretation, EPA's statutory interpretation extends to this
provision. Under section 185(a), the fees provision is expressly a
component of the attainment demonstration and, since the requirement
for an attainment demonstration is suspended, the requirement for its
components is also suspended when an area is monitoring attainment of
the standard. See 40 CFR section 51.918. EPA has taken the same
position with respect to the Reasonably Available Control Measures
(RACM) requirement, which is also a component of the attainment
demonstration. 70 FR 71645-71646 (November 29, 2005). EPA proposes to
find that Lake and Porter Counties are attaining the 1-hour ozone
standard, and, thus, the requirement for submitting a fee provision as
a component of the 1-hour attainment demonstration is suspended for so
long as the area is attaining the standard and until it is redesignated
to attainment.
Section 182(g) Milestones
    The Section 182(g) Milestones requirements are included in those
measures subject to EPA's interpretation in its Clean Data Policy
memorandum of May 10, 1995, and because EPA has determined that the
area has attained the 1-hour standard, the requirement of section
182(g) is not applicable for so long as the area attains the standard
and until it is redesignated to attainment. See also 40 CFR section
51.918.
Enhanced Ambient Monitoring
    On March 16, 1994 (59 FR 12168), EPA fully approved Indiana's SIP
revision establishing an enhanced monitoring program in Lake and Porter
Counties as required by section 182(c)(1) of the CAA.
Transportation Control Measures
    Within six years of November 15, 1990, and every three years
thereafter, section 182(c)(5) of the CAA requires states to submit a
demonstration of whether current aggregate vehicle mileage, aggregate
vehicle emissions,

congestion levels, and other relevant traffic-related and vehicle
emissions-related factors (collectively ``relevant parameters'') are
consistent with those used for the area's ozone demonstration of
attainment for serious and above 1-hour ozone nonattainment areas. If
the levels of relevant parameters that are projected in the attainment
demonstration are exceeded, a state has 18 months to develop and submit
a revision of the applicable state implementation plan to include TCMs
to reduce emissions to a level consistent with emissions levels in the
attainment demonstration for an area.
    Alternatively, EPA has determined that nonattainment areas are not
permanently locked into the estimates of future emissions given in the
initial SIP submittal, nor locked into those in any subsequently
approved amendment thereto. As we stated in the General Preamble, once
approved, the amended SIP revision would have the effect of increasing
the allowable motor vehicle emissions (including those due to changes
in the relevant parameters). See 57 FR 13498 at 13520 (April 16, 1992).
Thus, if actual emissions exceed those projected in an area's
attainment demonstration, a state may at any time before the area
reaches attainment, amend an area's SIP to demonstrate attainment while
altering the mix of emissions reductions in the SIP from various kinds
of sources (motor vehicle versus non-motor vehicle), rather than
include TCMs in the SIP.
    On April 30, 1998, Indiana submitted an ozone attainment
demonstration based on a range of possible emission control measures
reflecting various emission control alternatives and did not specify a
single set of emission control measures. On December 16, 1999 (64 FR
70514), the EPA proposed to conditionally approve the 1-hour ozone
attainment demonstration for Lake and Porter Counties. On December 21,
2000, Indiana submitted a SIP revision request consisting of a
demonstration that the Chicago-Gary-Lake County, IL-IN 1-hour ozone
nonattainment area would attain the 1-hour ozone NAAQS by November 15,
2007, the statutory attainment deadline for the area. The requested SIP
revision was fully approved on November 13, 2001 (66 FR 56944). EPA,
therefore, concludes that Indiana has complied with the substance of
section 182(c)(5) of the CAA, has no currently due section 182(c)(5)
obligations, and, by the virtue of EPA's approval of the 1-hour ozone
attainment demonstration, has never triggered an obligation under
section 182(c)(5) to include additional TCMs in the 1-hour ozone SIP
for Lake and Porter Counties. In addition, the section 182(c)(5)
requirements are also included in those measures subject to EPA's
interpretation under EPA's May 10, 1995 Clean Data Policy memorandum.
EPA therefore proposes in the alternative to find that since Lake and
Porter Counties are attaining the 1-hour ozone standard, any
requirement for submitting the section 182(c)(5) measures is suspended
for so long as the area is attaining the standard and until it is
redesignated to attainment. See also 40 CFR 51.918.
Vehicle Miles Traveled
    Section 182(d)(1)(A) of the CAA requires severe ozone nonattainment
areas to offset the growth in emissions attributable to growth in
Vehicle Miles Traveled (VMT); to select and implement TCMs necessary to
comply with the periodic emission reduction requirements of section
182(b) and (c); and, to consider TCMs specified in section 108(f), and
implement such TCMs as necessary to demonstrate attainment with the
ozone standard. Through rulemakings on July 28, 1995 (60 FR 38718) and
August 3, 2001 (66 FR 40829), EPA approved Indiana's TCMs as meeting
these requirements of the CAA.
NOX Requirements
    With respect to NOX requirements under section 182(f) of
the CAA, as discussed above, EPA has approved a NOX control
waiver for Lake and Porter Counties. See 61 FR 2428 (January 26, 1996).
In addition, we have approved Indiana NOX emission control
regulations adopted in response to EPA's NOX SIP call. See
66 FR 56465 (November 8, 2001) and 68 FR 69025 (December 11, 2003).
Emission Inventories
    Section 182(a)(1) requires that States submit comprehensive,
accurate, current inventories of actual emissions from all sources,
within 2 years of enactment of the CAA amendments of 1990. This
inventory requirement was approved on January 4, 1995 (60 FR 375).
Periodic VOC and NOX emission inventories were required to
be submitted every three years, beginning in November 15, 1995.
NOX and VOC emission inventory updates for 1999, 2002, and
2004 are contained in Indiana's September 12, 2006 submittal. EPA is
proposing to approve these emission inventory updates as meeting the
section 182(a)(3)(A) requirement of the CAA for periodic emission
inventory submissions under the 1-hour standard.
Ozone Attainment Demonstration
    As noted above, on November 13, 2001 (66 FR 56944), EPA fully
approved Indiana's 1-hour ozone attainment demonstration SIP revision
for the Chicago-Gary-Lake County, IL-IN 1-hour ozone nonattainment
area.
Contingency Measures
    Sections 172(c)(9) and 182(c)(9) of the CAA require ozone control
plans to contain measures to be implemented in the event that any
milestone in the ozone control plan is missed. EPA approved Indiana's
contingency measures for attainment of the 1-hour ozone standard in
Lake and Porter Counties in our approval of the State's ozone
attainment plan. See 66 FR 56944 (November 13, 2001).
    For the above reasons EPA believes that Indiana has met all
applicable part D requirements under the 1-hour ozone standard for
purposes of redesignation. It is noted that the State has committed to
maintain the VOC and NOX emission controls already in place.
    In addition, EPA has previously approved provisions in the Indiana
SIP addressing section 110 elements under the 1-hour standard. We have
analyzed the Indiana SIP as codified in 40 CFR part 52, subpart P, and
have determined that it is consistent with the requirements of section
110(a)(2) of the CAA.
    Therefore, with regard to compliance with the requirements for the
1-hour ozone standard, the State has met all applicable requirements
for purpose of redesignation under the 1-hour standard, were that
standard to be deemed reinstated. In addition, as discussed below, the
State's maintenance plan for the 8-hour standard also provides for
maintenance of the 1-hour standard (the area has an approvable ozone
maintenance plan and the State is committed to revise this plan within
8 years after the redesignation of the area to attainment). We also
find that, as set forth below, the area has achieved the ozone standard
due to the implementation of permanent, enforceable emission controls;
and the EPA has fully approved an ozone SIP meeting all requirements
applicable for purposes of redesignation. As noted below, the State of
Indiana and Lake and Porter Counties meet these requirements for the 8-
hour ozone NAAQS. We propose to find that Lake and Porter Counties
would also qualify for redesignation to attainment of the 1-hour ozone
NAAQS if this standard is deemed to be reinstated.

E. Are the Air Quality Improvements in Lake and Porter Counties and in
the Chicago-Gary-Lake County, IL-IN Nonattainment Area Due to Permanent
and Enforceable Emission Reductions Resulting From the Implementation
of the Indiana SIP and Applicable Federal Air Pollution Control
Regulations and Other Permanent and Enforceable Emission Reductions?

    To make the demonstration that the improvement in air quality is
due to permanent and enforceable emissions reductions, the State of
Indiana has documented changes in VOC and NOX emissions from
all anthropogenic (man-made or man-based) sources in Lake and Porter
Counties between 1999 and 2004, including 2002, an ozone standard
violation year, and 2004, one of the years in which the Chicago-Gary-
Lake County, IL-IN area attained the 8-hour ozone standard. The State
has also discussed the permanent and enforceable emission controls that
have been implemented in Lake and Porter Counties, in the State of
Indiana, and in other upwind areas that have contributed to the air
quality improvement in Lake and Porter Counties.
    Table 3 summarizes the VOC and NOX emissions totals from
the anthropogenic sources in Lake and Porter Counties for 1999 through
2004. From the table, it can be seen that both VOC and NOX
emissions in Lake and Porter Counties decreased between 1999 and 2004
and, most importantly, between 2002, an ozone standard violation year,
and 2004, an ozone standard attainment year.

 Table 3.--VOC and NOX Emissions from Anthropogenic Sources in Lake and
                 Porter Counties in Tons per Summer Day
------------------------------------------------------------------------
             Source sector                  1999       2002       2004
------------------------------------------------------------------------
VOC Emissions:
    Point..............................      28.84      24.58      25.62
    Area...............................      49.59      32.27      31.33
    On-Road Mobile.....................      33.29      20.00      18.90
    Non-Road Mobile....................      19.98      35.09      31.63
                                        --------------------------------
        Total..........................     131.70     111.94     107.48
NOX Emissions:
    Point..............................     214.58     186.44     148.20
    Area...............................      10.36       5.72       5.77
    On-Road Mobile.....................      49.92      55.00      65.95
    Non-Road Mobile....................      49.07      38.61      40.64
                                        --------------------------------
        Total..........................     323.93     285.77     260.56
------------------------------------------------------------------------

    Table 4 summarizes the NOX emission trends for Electric
Generating Units (EGUs) in Northwest Indiana (Jasper, Lake, LaPorte,
and Porter Counties) and statewide for 1999 through 2005.

  Table 4.--NOX Emission Trends for Electric Generating Units in Northwest Indiana and Statewide--Emissions in
                              Thousands of Tons per Ozone Season (April-September)
----------------------------------------------------------------------------------------------------------------
                   Area                       1999     2000     2001     2002     2003     2004     2005
---------------------------------------------------------------------------------------------------------
Northwest Indiana.........................     31.8     25.0     27.4     22.7     18.0     11.8     10.6
Statewide.................................    149.8    133.9    136.1    114.0     99.3     66.6     55.5
----------------------------------------------------------------------------------------------------------------

    As noted in Tables 3 and 4, the total VOC emissions in Lake and
Porter Counties and the EGU NOX emissions in Northwest
Indiana and statewide have declined between 1999 and 2004. IDEM notes
that these emission decreases have resulted from the implementation of
permanent and enforceable emission controls, such as implementation of
RACT rules, tighter Federal standards for new vehicles, Title IV of the
CAA, and NOX controls required by the Indiana NOX
SIP. Specifically in Lake and Porter Counties, the following emission
control measures were implemented: RACT rules found in volume 326 of
the Indiana Administrative Code (IAC) chapter 8 (326 IAC 8), including
IAC 8-1 (best available control technology for new source facilities),
IAC 8-2 (surface coating emission limitations), IAC 8-3 (solvent
degreasing controls), IAC 8-4 (petroleum source controls), IAC 8-5
(miscellaneous operation controls), and IAC 8-6 (organic solvent
emission limitations); VOC emission controls implemented to meet Rate-
Of-Progress (ROP) requirements, including the following:

1. Enhanced Vehicle Inspection and Maintenance
2. Stage II Vapor Recovery on Gasoline Marketing Sources
3. Reformulated Gasoline
4. National VOC Emission Standards for Architectural Coatings
5. Residential Open Burning Ban
6. Non-Control Technology Guideline Source RACT
7. National Emission Standards for Benzene from Coke Oven By-Product
Recovery Plants
8. National Emission Standards for Coke Oven Batteries
9. Federal Phase I Reformulated Gasoline for Small Non-Road Engines
10. Federal Controls on Small Spark-Ignited Engines
11. Commercial/Consumer Solvent Reformulation Rule
12. Volatile Organic Liquid Storage RACT
13. Sinter Plant Rule
14. Municipal Solid Waste Landfill Rule
15. Petroleum Refineries National Emission Standard for Hazardous Air
Pollutants
16. Banning of the Use of Untreated Water for Quenching, and,

17. Cold Cleaner Degreaser RACT (an extension of 326 IAC 8-3).
NOX emission controls in Lake and Porter County resulted
from the implementation of the NOX emission control
requirements and emission caps included in the State's NOX
SIP. Beginning in 2004, this set of NOX control rules
accounted for a reduction of approximately 33 percent statewide from
2003 EGU emissions. IDEM also notes that other states have also
implemented similar NOX emission controls, resulting in
reduced ozone and ozone precursor transport into Lake and Porter
Counties and into the Chicago-Gary-Lake County, IL-IN ozone
nonattainment area.

    IDEM is convinced that all of these VOC and NOX emission
controls, which are permanent and enforceable, are responsible for the
observed ozone air quality improvement in Lake and Porter Counties and
have contributed significantly to the attainment of the 8-hour ozone
NAAQS in the Chicago-Gary-Lake County, IL-IN area. See also the
discussion of Temperature Ozone Exceedance Frequency Study in section
VII B. of this proposal.
    Besides the State's VOC RACT, ROP, and NOX emission
control requirements, other Federal emission control requirements have
recently resulted in VOC and NOX emission reductions or will
shortly further reduce VOC and NOX emissions in Northwest
Indiana and throughout the Chicago-Gary-Lake County, IL-IN area. These
emission reduction requirements include the following:
    Tier 2 Emission Standards for Vehicles and Gasoline Sulfur
Standards. These emission control requirements result in lower
emissions from new cars and light duty trucks, including sport utility
vehicles. The Federal rules are being phased in between 2004 and 2009.
The EPA has estimated that, by the end of the phase-in period, the
following vehicle NOX emission reductions will occur
nationwide: Passenger cars (light duty vehicles) (77 percent); light
duty trucks, minivans, and sports utility vehicles (86 percent; and
larger sports utility vehicles, vans, and heavier trucks (69 to 95
percent). VOC emission reductions are also expected to range from 12 to
18 percent, depending on vehicle class, over the same period. Although
some of these emission reductions have already occurred by the 2004-
2006 attainment years, most of these emission reductions will occur
during the maintenance period for Lake and Porter Counties.
    Heavy-Duty Diesel Engines. In July 2000, EPA issued a final rule to
control the emissions from highway heavy duty diesel engines, including
low-sulfur diesel fuel standards. These emission reductions are being
phased in between 2004 and 2007. This rule is expected to result in a
40 percent decrease in NOX emissions from heavy duty diesel
vehicles.
    Non-Road Diesel Rule. Issued in May 2004, this rule generally
applies to new stationary diesel engines used in certain industries,
including construction, agriculture, and mining. In addition to
affecting engine design, this rule includes requirements for cleaner
fuels. It is expected to reduce NOX emissions from these
engines by up to 90 percent, and to significantly reduce particulate
matter and sulfur emissions from these engines in addition to the
NOX emission reduction. This rule did not affect 2004
emissions from these sources, but will limit emissions from new engines
beginning in 2008.
    Indiana commits to maintain all existing emission control measures
that affect Lake and Porter Counties and the Chicago-Gary-Lake County,
IL-IN area after Lake and Porter Counties are redesignated to
attainment of the 8-hour ozone NAAQS. All changes in existing rules
affecting Lake and Porter Counties and new rules subsequently needed to
provide for the maintenance of the 8-hour ozone NAAQS in Lake and
Porter Counties will be submitted to the EPA for approval as SIP
revisions.
    Thus, EPA proposes to determine that Lake and Porter Counties have
met the requirement of section 107(d)(3)(E)(iii) of the CAA that the
improvement in air quality is due to permanent and enforceable
emissions reductions.

F. Do Lake and Porter Counties Have a Fully Approvable Ozone
Maintenance Plan Pursuant to Section 175A of the CAA?

    In conjunction with its request to redesignate Lake and Porter
Counties to attainment of the ozone NAAQS, Indiana submitted a SIP
revision request to provide for maintenance of the 8-hour ozone NAAQS
in this area for at least 10 years after the redesignation of this area
to attainment of the 8-hour ozone NAAQS. EPA proposes to approve this
maintenance plan pursuant to section 175A and section 107(d)(3)(E)(iv)
of the CAA.
1. What Is Required in an Ozone Maintenance Plan?
    Section 175A of the CAA sets forth the required elements of air
quality maintenance plans for areas seeking redesignation from
nonattainment to attainment of a NAAQS. Under section 175A, a
maintenance plan must demonstrate continued attainment of the
applicable NAAQS for at least 10 years after the Administrator approves
the redesignation to attainment. Within eight years after the
redesignation, the State must submit a revised maintenance plan which
demonstrates maintenance of the standard for 10 years following the
initial 10-year maintenance period. To address the possibility of
future NAAQS violations, the maintenance plan must contain such
contingency measures, with a schedule for implementation, as EPA deems
necessary, to assure prompt correction of any future NAAQS violations.
The September 4, 1992 John Calcagni memorandum provides additional
guidance on the content of maintenance plans. An ozone maintenance plan
should, at minimum, address the following items: (1) The attainment VOC
and NOX emissions inventories; (2) a maintenance
demonstration showing maintenance for the 10 years of the maintenance
period; (3) a commitment to maintain the existing monitoring network;
(4) factors and procedures to be used for verification of continued
attainment; and, (5) a contingency plan to prevent and/or correct a
future violation of the NAAQS.
2. What Are the Attainment Emission Inventories for Lake and Porter
Counties?
    IDEM prepared comprehensive VOC and NOX emission
inventories for Lake and Porter Counties, including point (significant
stationary sources individually inventoried), area (smaller and widely-
distributed stationary sources collectively inventoried by source type
and geographical area), mobile on-road, and mobile non-road sources for
2004 (the redesignation request's base year/attainment year). To
develop the attainment year emission inventories, IDEM used the
following approaches and sources of data.
a. Point Sources
    2004 point source emissions were compiled using IDEM's annual
emissions statement database and the 2005 EPA Air Markets acid rain
emissions inventory database.
b. Area Sources
    Area source VOC and NOX emissions were projected from
Indiana's 2002 base year emissions inventory, which was previously
submitted to EPA's National Emissions Inventory system. The
documentation of this base year emissions inventory has been submitted
by the State, and is reviewed elsewhere in this proposed rule.

c. On-Road Mobile Sources
    Mobile source emissions were calculated using the MOBILE6 emission
factor model and traffic data (vehicle miles traveled, vehicle speeds,
and vehicle type and age distributions by roadway link and area)
developed using the region's travel-demand model. IDEM has provided
detailed data summaries to document the calculation of on-road mobile
source VOC and NOX emissions for 2004, as well as for the
projection years of 2010 and 2020 (further discussed below).
d. Non-Road Mobile Sources
    2004 non-road mobile source emissions were projected for the 2002
National Emissions Inventory (NEI) non-road mobile source emissions
developed by the EPA. IDEM used the NEI emissions along with growth
factors to grow the non-road mobile source emissions to 2004. To
address concerns about the accuracy of some of the emissions for
various source categories in EPA's non-road emissions, the Lake
Michigan Air Directors Consortium (LADCO) contracted with several
consulting companies to review the base data used by the EPA and to
make recommendations for corrections to the model used to calculate the
2002 emissions. Emissions were estimated for commercial marine vessels
and railroads. Recreational motorboat populations and surrogates (used
to assign emissions to each county) were updated by contracted
consultants. The populations for the construction equipment category
were reviewed and updated based on surveys completed in the Midwest,
and the temporal allocation of agricultural sources was also updated.
Based on these and other updates, the EPA revised the non-road
estimation model for 2002, which was used for the basis for the
projected 2004 non-road mobile source emissions.
    The 2004 attainment year VOC and NOX emissions for Lake
and Porter Counties are summarized along with the 2010 and 2020
projected emissions in Tables 5 below. We agree that the State has
acceptably derived and documented the attainment year VOC and
NOX emissions for Lake and Porter Counties.
3. Has the State Demonstrated Maintenance of the Ozone Standard in Lake
and Porter Counties and in the Chicago-Gary-Lake County, IL-IN Ozone
Nonattainment Area?
    As part of the September 12, 2006 redesignation request submittal,
IDEM included a requested revision to the SIP to incorporate an ozone
maintenance plan as required under section 175A of the CAA. The
maintenance plan includes an ozone maintenance demonstration based on
the comparison of projected emissions to the attainment year emissions
levels. This demonstration shows that future (2010 and 2020) VOC and
NOX emissions remain at or below the 2004 attainment year
levels. Note that a maintenance demonstration need not be based on
modeling. See Wall v. EPA, 265 F.3d 426 (6th Cir. 2001), Sierra Club v.
EPA, 375 F.3d 537 (7th Cir. 2004). See also 66 FR 53094, 53099-53100
(October 19, 2001) and 68 FR 25430-25432 (May 12, 2003).
    Table 5 specifies the VOC and NOX emissions in Lake and
Porter Counties for 2004, 2010, and 2020. IDEM chose 2020 as the
maintenance projection year to meet the 10-year maintenance projection
requirement, allowing time for the EPA to approve the redesignation
request and maintenance plan. IDEM also chose 2010 as an interim year
to demonstrate that VOC and NOX emissions will remain below
the attainment year levels throughout the maintenance period.

  Table 5.--Attainment Year and Projected VOC and NOX Emissions in Lake
               and Porter Counties in Tons per Summer Day
------------------------------------------------------------------------
                                             Years
         Source sector         --------------------------------
                                   2004       2010       2020
---------------------------------------------------------------
VOC Emissions:
    Point.....................      25.62      25.36      30.84
    Area......................      31.33      31.72      34.31
    On-Road Mobile............      18.90       9.93       5.71
    Non-Road Mobile...........      31.63      24.44      20.26
                               -----------------------------------------
        Total.................     107.48      91.45      91.12
NOX Emissions
    Point.....................     148.20      97.06     102.15
    Area......................       5.77       6.07       6.40
    On-Road Mobile............      65.95      38.65      11.97
    Non-Road Mobile...........      40.64      33.95      28.51
                               -----------------------------------------
        Total.................     260.56     175.73     149.03
------------------------------------------------------------------------

    Using emissions data provided by LADCO for the remainder of the
Chicago-Gary-Lake County, IL-IN ozone nonattainment area (for the
Illinois portion of this area), IDEM has also determined the VOC and
NOX emissions for the entire nonattainment area. These VOC
and NOX emissions are summarized in Table 6.

  Table 6.--Attainment Year and Projected VOC and NOX Emissions in the
  Chicago-Gary-Lake County, IL-IN Ozone Nonattainment Area in Tons per
                               Summer Day
------------------------------------------------------------------------
                                             Years
         Source sector         --------------------------------
                                   2004       2010       2020
---------------------------------------------------------------
VOC Emissions:
    Point.....................      97.65      94.35     128.84
    Area......................     225.34     221.72     234.32

    On-Road Mobile............     198.90     165.27     100.60
    Non-Road Mobile...........     159.63     109.44     122.25
                               -----------------------------------------
        Total.................     681.52     590.78     586.01
NOX Emissions:
    Point.....................     442.21     301.06     334.15
    Area......................      45.77      53.07      57.40
    On-Road Mobile............     464.95     314.59     145.08
    Non-Road Mobile...........     321.64     242.95     101.51
                               -----------------------------------------
        Total.................    1274.57     911.67     638.14
------------------------------------------------------------------------

    Tables 5 and 6 show that VOC and NOX emissions are
projected to decline in both Lake and Porter Counties and in the
Chicago-Gary-Lake County, IL-IN ozone nonattainment area after 2004.
This demonstrates maintenance of the ozone standard in these areas
through 2020 and throughout the ozone maintenance period.
    IDEM also notes that the State's EGU NOX emission
control rules stemming from EPA's NOX SIP call, implemented
beginning in 2004, with additional NOX emission reductions
expected to result from the implementation of new Phase 2
NOX rules, and the Clean Air Interstate Rule (CAIR) will
further lower NOX emissions throughout Northwest Indiana, in
the Chicago-Gary-Lake County, IL-IN area, statewide in Indiana, and in
other upwind states, resulting in decreased ozone and ozone precursor
transport into Lake and Porter Counties and the Chicago-Gary-Lake
County area. This will also support maintenance of the ozone standard
in the Chicago-Gary-Lake County area.
    IDEM has documented some of the procedures used to project
emissions. On-road mobile sources were projected using the MOBILE6
emission factor model and projected traffic data obtained from the
Northwest Indiana Regional Planning Commission (NIRPC), which maintains
a travel demand forecast model that is capable of projecting changes in
total daily VMT. Emissions for the other major source sectors were
determined using projected source activity/growth data provided by
LADCO, as well as major source emissions data obtained periodically for
all major sources statewide.
    Based on the comparison of the projected emissions and the
attainment year emissions, we conclude that IDEM has successfully
demonstrated that the 8-hour ozone standard should be maintained in
Lake and Porter Counties and in the Chicago-Gary-Lake County, IL-IN
area. We believe that this is especially likely given the expected
impacts of the NOX SIP call and CAIR. As noted by IDEM, this
conclusion is further supported by the fact that other states in the
eastern portion of the United States are expected to further reduce
regional NOX emissions through implementation of their own
NOX emission control rules for EGUs and other NOX
sources and through implementation of CAIR, reducing ozone and
NOX transport into Lake and Porter Counties.
    The demonstration of maintenance for the 8-hour standard also
demonstrates maintenance for the 1-hour standard because the same
attainment year and maintenance year emissions inventories that show
maintenance for the 8-hour standard similarly show maintenance for the
1-hour standard. As demonstrated above, future VOC and NOX
emissions are projected to remain at or below the 2004 attainment year
levels.
4. What Is the Contingency Plan for Lake and Porter Counties?
a. Verification of Continued Attainment
    Continued attainment of the 8-hour ozone NAAQS in Lake and Porter
Counties and in the Chicago-Gary-Lake County, IL-IN area depends on the
State's efforts toward tracking applicable indicators during the
maintenance period and taking appropriate actions if trends in the
indicators indicate that additional emission reductions are needed to
correct an existing or developing air quality problem. The State's plan
for verifying continued attainment of the 8-hour ozone standard in
these areas consists, in part, of a plan to continue ambient monitoring
in Lake and Porter Counties and to track ozone air quality in the
maintenance area, including the Illinois portion of the Chicago-Gary-
Lake County area and the Chiwaukee Prairie, WI monitor. In addition,
IDEM will periodically revise and review the VOC and NOX
emissions for Lake and Porter Counties to assure that emissions growth
is not threatening the continued attainment of the 8-hour standard in
this area. Revised emission inventories for this area will be prepared
for 2005, 2008, and 2011 as necessary to comply with the emission
inventory reporting requirements established in the CAA. The revised
emissions will be compared with the 2004 attainment emissions and the
2020 projected maintenance year emissions to assure continued
maintenance of the ozone standard.
b. Contingency Plan
    The contingency plan provisions of the CAA are designed to result
in prompt correction or prevention of violations of the NAAQS that
might occur after redesignation of an area to attainment of the NAAQS.
Section 175A of the CAA 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 might occur after
redesignation. The maintenance plan must identify the contingency
measures to be considered for possible adoption, a schedule and
procedure for adoption and implementation of the selected contingency
measures, and a time limit for action by the State. The State should
also identify specific indicators to be used to determine when the
contingency measures need to be adopted and implemented. The
maintenance plan must include a requirement that the State will
implement all measures with respect to control of the pollutant(s) that
were controlled in the SIP before the redesignation of the area to
attainment. See section 175A(d) of the CAA.

    As required by section 175A of the CAA, Indiana has adopted a
contingency plan to address a possible future ozone air quality
problem. The contingency plan has two levels of actions/responses
depending on whether a violation of the 8-hour ozone standard is only
threatened (Warning Level Response) or has actually occurred (Action
Level Response).
    A Warning Level Response will be prompted whenever an annual (1-
year) fourth-high monitored daily maximum 8-hour ozone concentration of
0.089 ppm occurs in a single ozone season or a 2-year averaged fourth-
high monitored daily maximum 8-hour ozone concentration of 0.085 ppm or
greater occurs within the maintenance area. A Warning Level Response
will consist of a study to determine whether the ozone concentration
indicates a trend toward higher ozone concentrations or whether
emissions appear to be increasing. The study will evaluate whether the
trend, if any, is likely to continue and, if so, the control measures
necessary to reverse the trend taking into consideration ease and
timing for implementation, as well as economic considerations.
Implementation of necessary controls in response to the Warning Level
Response trigger will take place as expeditiously as possible, but in
no event later than 12 months from the conclusion of the most recent
ozone season (September 30). If new emission controls are needed to
reverse the adverse ozone/emissions trend, the procedure for emission
control selection under the Action Level Response will be followed.
    An Action Level Response will be triggered when a violation of the
8-hour ozone standard is monitored at any of the monitors in the area.
On February 20, 2007, IDEM submitted a letter to the EPA clarifying
that an Action Level Response will be triggered if a future violation
of the 8-hour ozone NAAQS is monitored within any part of the Chicago-
Gary-Lake County, IL-IN area or at the Chiwaukee Prairie monitoring
site in Kenosha County, Wisconsin. In the event that the Action Level
is triggered and is not found to be due to an exceptional event,
malfunction, or noncompliance with a source permit condition or rule
requirement, IDEM will determine additional control measures needed to
assure future attainment of the ozone NAAQS. In this case emission
control measures that can be implemented in a short time will be
selected in order to be implemented within 18 months from the close of
the ozone season that prompted the Action Level Response.
    Adoption of any additional emission control measures prompted by
either of the two response levels will be subject to the necessary
administrative and legal processes dictated by State law. This process
will include publication of public notices, providing the opportunity
for a public hearing, and other measures required by Indiana law for
rulemaking by State environmental boards. If a new emission control
measure is already promulgated and scheduled for implementation at the
Federal or State level, and that emission control measure is determined
to be sufficient to address the air quality problem or adverse trend,
additional local emission control measures may be determined to be
unnecessary. IDEM will submit to the EPA an analysis to demonstrate
that the proposed emission control measures or existing emission
control measures are adequate to return the area to attainment. As
discussed below, EPA understands that Indiana will commit to submit any
such proposed or existing emission control measure to EPA as a SIP
revision.
    Contingency measures contained in the maintenance plan are those
emission controls or other measures that the State may choose to adopt
and implement in response to either an Action Level or a Warning Level
trigger. These include, but are not limited to, the following:
    i. Vehicle emissions testing program enhancements, including liquid
leak inspection; increased vehicle weight limit cutoffs; addition of
diesel vehicles; etc.;
    ii. Asphalt paving VOC content restrictions (lower VOC formulation
requirements);
    iii. Diesel exhaust retrofits;
    iv. Traffic flow improvements;
    v. Vehicle idle reduction programs;
    vi. Portable fuel container regulation (statewide);
    vii. Park and ride facilities;
    viii. Rideshare/carpool programs;
    ix. VOC cap-and-trade program for major stationary sources; and,
    x. Commercial/consumer solvent VOC content limits (statewide).
    No contingency measure will be implemented without providing the
opportunity for full public participation in the selection and adoption
of controls. During this process, the relative costs and benefits of
individual control measures would be evaluated.
    EPA notes that two aspects of the contingency plan merit further
discussion. First, the plan does not require the adoption and
implementation of new emission controls in the event of a future ozone
standard violation if it can be shown that the ozone standard violation
is due to an exceptional event, source malfunction, or source
noncompliance. If a monitored exceedance is determined to be due to an
exceptional event, it will no longer be considered in determining
whether a violation has occurred. With regard to source malfunctions or
source noncompliance, we note that the Indiana SIP contains provisions
for ensuring that sources take actions to correct malfunctions, as well
as provisions for the State to take enforcement actions against
noncompliant sources. EPA believes that this provides a mechanism for
the State to take prompt corrective action, including expeditious and
effective enforcement action to achieve compliance. See an analogous
discussion in the General Preamble, 57 FR 13547 (April 16, 1992). In
the context of section 172(c)(9) contingency measures for sulfur
dioxide (SO2), EPA has interpreted ``contingency measures''
``to mean that the State agency has a comprehensive program to identify
sources of violations of the NAAQS and to undertake an aggressive
follow-up for compliance and enforcement, including expedited
procedures for establishing enforceable consent agreements pending the
adoption of revised SIPs.'' This type of source-specific noncompliance
and correction by enforcement action in the ozone context is similar to
source-specific SO2 noncompliance and enforcement, and
therefore it is appropriate to apply the SO2 guidance in
this circumstance.
    Second, the maintenance plan does not call for the State to adopt
and implement new contingency measures if it can be shown that an
already adopted emission control measure (State or Federal) will
eliminate an ozone air quality problem. We believe that such an
emission control measure should become part of the SIP. Prior to final
rulemaking, Indiana must commit that it will submit such a measure as a
SIP revision, and final approval of the maintenance plan is conditioned
upon the State committing to submit such measures as requested SIP
revisions. Indiana has indicated that they will make such a commitment.
This issue aside, we otherwise propose to approve the ozone maintenance
plan as providing for maintenance of both the 8-hour and 1-hour
standards, if that standard is deemed to be reinstated. With respect to
maintenance of the 1-hour standard, EPA has determined that the 8-hour
NAAQS provides increased public health protection as compared to the 1-
hour ozone standard. See 62 FR at 38859 (July 18, 1997). Because the 8-
hour standard is more stringent than the 1-hour standard, a maintenance
plan

with triggers tied to the 8-hour standard will be more protective of
public health than a maintenance plan with contingency measure triggers
tied to the 1-hour standard.
5. Has the State Committed To Update the Ozone Maintenance Plan in
Eight Years After the Redesignation of Lake and Porter Counties to
Attainment of the 8-Hour Ozone NAAQS?
    As required by section 175A(b) of the CAA, the State commits to
submit to the EPA an update of the ozone maintenance plan eight years
after redesignation of Lake and Porter Counties to attainment of the 8-
hour ozone NAAQS. The updated maintenance plan will provide maintenance
of the 8-hour ozone standard for an additional 10 years beyond the
first 10 years of maintenance of the standard.

VI. Has the State Adopted Acceptable MVEBs for the End Year of the
Ozone Maintenance Period Which Can Be Used To Support Transportation
Conformity Determinations?

A. How Are the MVEBs Developed and What Are the MVEBs for Lake and
Porter Counties?

    Under the CAA, states are required to submit, at various times, SIP
revisions and ozone maintenance plans for applicable areas (for ozone
nonattainment areas and for areas seeking redesignations to attainment
of the ozone standard or revising existing ozone maintenance plans).
These emission control SIP revisions (e.g., reasonable further progress
and attainment demonstration SIP revisions), including ozone
maintenance plans, must create MVEBs based on on-road mobile source
emissions allocated to highway and transit vehicle use that, together
with emissions from other sources in the area, will provide for
attainment or maintenance of the ozone NAAQS.
    Under 40 CFR part 93, MVEBs for an area seeking a redesignation to
attainment of the NAAQS must be established for the last year of the
maintenance plan. The MVEBs serve as ceilings on emissions from an
area's planned transportation system. The MVEB concept is further
explained in the preamble to the November 24, 1993 transportation
conformity rule (58 FR 62188). The preamble also describes how to
establish the MVEBs in the SIP and how to revise the MVEBs if needed.
    Under section 176(c) of the CAA, new transportation projects, such
as the construction of new highways, must ``conform'' to (i.e., be
consistent with) the SIP. Conformity to the SIP means that
transportation activities will not cause or contribute to new air
quality standard violations, increase the frequency or severity of
existing violations, or delay timely attainment of the NAAQS. CAA
section 176(c)(1). If a transportation plan does not conform, most new
transportation projects that would expand the capacity of roadways
cannot go forward. Regulations at 40 CFR part 93 set forth EPA's
policy, criteria, and procedures for demonstrating and assuring
conformity of transportation activities to a SIP.
    When reviewing SIP revisions containing MVEBs, including attainment
strategies, rate-of-progress plans, and maintenance plans, EPA must
find that the MVEBs are ``adequate'' for use in determining
transportation conformity. Once EPA finds the submitted MVEBs to be
adequate for transportation conformity purposes, the MVEBs are used by
state and Federal agencies in determining whether proposed
transportation projects conform to the SIPs as required by section
176(c) of the CAA. EPA's criteria for determining the adequacy of MVEBs
are specified in 40 CFR 93.118(e)(4).
    EPA's process for determining adequacy of MVEBs consists of three
basic steps: (1) Providing public notification of a SIP submission; (2)
providing the public the opportunity to comment on the MVEBs during a
public comment period; and, (3) making a finding of adequacy. The
Transportation Conformity Rule, in 40 CFR 93.118(f), provides for MVEB
adequacy findings through two mechanisms. First, 40 CFR 93.118(f)(1)
provides for posting a notice to the EPA conformity Web site at: http://www.epa.gov/otaq/stateresources/transconf/adequacy.htm
 and providing a

30-day public comment period. Second, a mechanism is described in 40
CFR 93.118(f)(2) which provides that EPA can review the adequacy of an
implementation plan MVEB simultaneously with its review of the
implementation plan itself. In this notice, EPA is using the second
mechanism in 40 CFR 93.118(f)(2) and is taking comment on both the
adequacy and approvability of the submitted MVEBs.
    The Lake and Porter Counties' ozone maintenance plan contains VOC
and NOX MVEBs for 2020 and also for 2010. The State has the
option of setting budgets for earlier years in the maintenance plan in
addition to the last year of the maintenance plan. Indiana has
submitted budgets for both the 2010 year and also the 2020 year. EPA is
taking comment on both the adequacy and approvability of the submitted
VOC and NOX MVEBs for Lake and Porter Counties. Any and all
comments on the adequacy and approvability of the MVEBs should be
submitted during the comment period stated in the DATES section of this
notice.
    EPA intends to make its determination of the adequacy of the 2010
and 2020 MVEBs for Lake and Porter Counties for transportation
conformity purposes in the final rulemaking on the 8-hour ozone
redesignation. If EPA finds the 2010 and 2020 MVEBs adequate and
approves the MVEBs in the final rulemaking action, the new MVEBs must
be used for future transportation conformity determinations. The new
MVEBs, if found adequate and approved in the final rulemaking, will be
effective the date of publication of EPA's final rulemaking in the
Federal Register. For required regional emissions analysis years that
involve the year 2009 or before, the applicable budget for the purposes
of conducting transportation conformity will be the MVEBs for Lake and
Porter Counties in the approved 1-hour ozone maintenance plan. For
required regional emissions analysis years that involve 2010 or beyond,
the applicable budgets are defined in the table below.

                    Lake and Porter County Area MVEBs
                             [Tons per day]
------------------------------------------------------------------------
                         Year                             VOC      NOX
------------------------------------------------------------------------
2010..................................................     11.5     40.6
2020..................................................      6.0     12.6
------------------------------------------------------------------------

    These MVEBs will be separate state area budgets for Lake and Porter
Counties, Indiana. Illinois will establish MVEBs for the remainder of
the Chicago 8-hour ozone area through the 8-hour ozone SIP submitted by
Illinois.
    EPA, through this rulemaking, is proposing to approve the MVEBs for
both 2020 and 2010, as part of the 8-hour maintenance plan, to be used
to determine transportation conformity in Lake and Porter Counties. EPA
has determined that the budgets are consistent with the control
measures in the SIP and that Lake and Porter Counties can maintain
attainment of the 8-hour ozone NAAQS (projected VOC and NOX
emissions for 2010 and 2020 remain below the attainment year, 2004,
levels) for the relevant required 10-year period with mobile source
emissions at the levels of the MVEBs. It should be noted that the
current approved 1-hour ozone budgets, which were approved as part of
the 1-hour ozone attainment

demonstration, will continue to be used for transportation conformity
purposes through 2009. The current 1-hour ozone budgets that are being
used for transportation conformity purposes are for the 2007 year and
cap emissions at 12.37 tons per day for VOCs and 63.33 tons per day for
NOX. When the 8-hour ozone maintenance plan MVEBs are
approved or found adequate, the new 2010 and 2020 budgets will provide
a lower cap on emissions in Lake and Porter Counties because the new
budgets are lower than the current 2007 budgets. IDEM has determined
the 2010 MVEBs for Lake and Porter Counties to be 11.5 tons per day of
VOC and 40.6 tons per day of NOX. IDEM has also determined
the 2020 MVEBs for Lake and Porter Counties to be 6.0 tons per day for
VOC and 12.6 tons per day for NOX. It should be noted that
these MVEBs exceed the on-road mobile source VOC and NOX
emissions projected by IDEM for 2010 and 2020, as summarized in Table 5
above (``On-Road Mobile'' source sector). Through discussions with all
organizations involved in transportation planning for Lake and Porter
Counties, IDEM decided to include safety margins of 5 percent (0.29
tons per day for VOC and 0.63 tons per day for NOX for 2020)
in the MVEBs to provide for mobile source growth not anticipated in the
projected 2010 and 2020 emissions and for a margin of error in the
calculation of future mobile source emissions. Indiana has demonstrated
that Lake and Porter Counties can maintain the 8-hour ozone NAAQS with
these mobile source emissions since total source emissions including
the increased mobile source emissions will remain under the attainment
year emission levels.

B. Are the MVEBs Approvable?

    The submitted MVEBs meet the criteria for adequacy. The submitted
SIP was endorsed by the Governor and was subject to a State public
hearing. The MVEBs were discussed during consultation among Federal,
state and local agencies. The MVEBs are clearly identified and
precisely quantified in the submitted SIP. The MVEBs, when considered
together with all other emissions sources, are consistent with
applicable requirements for maintenance. The MVEBs are consistent with
and clearly related to the emissions inventory and the control measures
in the submitted maintenance plan; and the established safety margins
are within the allowable limits. No negative comments were received at
the State public hearing which addressed the MVEBs in the maintenance
plan.
    The 2010 and 2020 VOC and NOX MVEBs for Lake and Porter
Counties are approvable because the MVEBs meet all of the above
criteria and maintain the total VOC and NOX emissions for
Lake and Porter Counties at or below the attainment year emission
inventory levels, as required by the transportation conformity
regulations. These MVEBs are adequate and approvable for transportation
conformity purposes.

VII. Modeled Attainment of the Ozone Standard

    Although EPA does not require use of air quality models to support
ozone redesignation requests, IDEM has chosen to review existing
modeling results to support the view that the 8-hour ozone NAAQS has
been attained in Lake and Porter Counties and in the Chicago-Gary-Lake
County, IL-IN area due to the implementation of permanent and
enforceable emission controls, and that attainment of the ozone
standard will be maintained in these areas as the result of
implementation of additional emission controls already adopted. In
addition, analyses of modeling results and other related meteorological
data also allowed IDEM to assess the impacts of changes in meteorology
on area peak ozone concentrations to support the case that changes in
emissions are responsible for attainment of the ozone standard in these
areas and not changes in meteorology.

A. Regional Ozone Modeling Results

    Regional ozone modeling has been conducted to support several
national emission control efforts and to support the preparation of 8-
hour ozone attainment demonstrations in the Lake Michigan region. The
results of these modeling studies have been reviewed for their modeled
ozone concentrations in Lake and Porter Counties and the rest of the
Chicago-Gary-Lake County area. The conclusions based on these modeling
studies are summarized here.
EPA Modeling Analysis for Heavy-Duty Engine and Diesel Fuel Rules
    EPA conducted ozone modeling to support the Tier II vehicle and
low-sulfur fuel rules. The results of the modeling were documented in
the report ``Technical Support Document for the Heavy Duty Engine and
Vehicle Standards and Highway Diesel Fuel Sulfur Control Requirements:
Air Quality Modeling Analyses'' (EPA 420-R-00-028). IDEM reviewed these
documented modeling results, and notes that this modeling study shows