[Federal Register Volume 68, Number 214 (Wednesday, November 5, 2003)]
[Proposed Rules]
[Pages 62690-62729]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-27372]



[[Page 62689]]

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Part III





Environmental Protection Agency





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40 CFR Part 93



Transportation Conformity Rule Amendments for the New 8-Hour Ozone and 
PM2.5 National Ambient Air Quality Standards and 
Miscellaneous Revisions for Existing Areas; Proposed Rule

Federal Register / Vol. 68, No. 214 / Wednesday, November 5, 2003 / 
Proposed Rules

[[Page 62690]]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 93

[FRL-7579-8]
RIN 2060-AL73


Transportation Conformity Rule Amendments for the New 8-Hour 
Ozone and PM2.5 National Ambient Air Quality Standards and 
Miscellaneous Revisions for Existing Areas

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

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SUMMARY: Today we (EPA) are proposing to amend the transportation 
conformity rule to include criteria and procedures for the new 8-hour 
ozone and fine particulate matter (PM2.5) national ambient 
air quality standards (NAAQS or ``standards''). Transportation 
conformity is required under Clean Air Act section 176(c) to ensure 
that federally supported highway and transit project activities are 
consistent with (``conform to'') the purpose of a State air quality 
implementation plan (SIP). We are conducting this rulemaking to revise 
the conformity regulation in the context of EPA's broader strategies 
for implementing the new ozone and PM2.5 standards.
    The proposal provides guidance for when conformity will first apply 
in areas that are designated nonattainment for the 8-hour ozone and 
PM2.5 standards. This portion of the proposal discusses the 
implementation of the statutory one-year conformity grace period and 
proposed revocation of the 1-hour ozone standard, although EPA is not 
seeking comment through today's proposal on the revocation options 
themselves. Today's proposal also describes when transportation 
conformity applies in areas that have approved 8-hour ozone Early 
Action Compacts (EACs).
    The proposal also describes the general requirements for conducting 
conformity determinations for the new standards, such as the conformity 
test(s) that would apply before and after adequate or approved SIP 
motor vehicle emissions budgets are established. In addition, this 
rulemaking proposes to amend the conformity regulations to specifically 
include PM2.5 as a criteria pollutant subject to 
transportation conformity and outlines the specific conformity 
requirements that would apply in newly designated PM2.5 
nonattainment areas. In particular, the proposal includes options for 
when conformity would apply for various PM2.5 precursors and 
fugitive dust, as well as options for PM2.5 hot-spot 
requirements for project-level conformity determinations. EPA seeks 
comments and suggestions for future guidance on adjusting fugitive dust 
emissions for PM2.5 conformity analyses.
    In addition to issues related to the new ozone and PM2.5 
standards, EPA is proposing a few miscellaneous rule revisions to 
clarify the existing regulation and improve implementation.
    The Department of Transportation (DOT) is EPA's Federal partner in 
implementing the transportation conformity regulation. We have 
consulted with DOT on the development of this rulemaking and DOT 
concurs with this proposal. EPA has also met with transportation and 
environmental organizations to discuss this rulemaking and the proposal 
reflects the comments that we received through these stakeholder 
discussions.

DATES: Written comments on this proposal must be received on or before 
December 22, 2003. EPA will conduct one public hearing on this proposal 
beginning at 9:30 a.m. on Thursday, December 4, 2003, in Washington, 
DC. As described in Section XVI. of this proposal, the hearing will 
continue throughout the day until all testimony has been presented or 5 
p.m., whichever is earlier.

ADDRESSES: Comments may be submitted by mail to: Air Docket, 
Environmental Protection Agency, Mailcode: 6102T, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460, Attention Docket ID No. OAR-2003-0049. 
Comments may also be submitted electronically, by facsimile, or through 
hand delivery/courier. Follow the detailed instructions for submission 
as provided in section I.C. of the SUPPLEMENTARY INFORMATION section.
    The public hearing will be held in Washington, DC, at the 
Washington Marriott Hotel at 1221 22nd St., NW., Washington, DC 20037, 
(202) 872-1500.

FOR FURTHER INFORMATION CONTACT: Meg Patulski, State Measures and 
Conformity Group, Transportation and Regional Programs Division, U.S. 
Environmental Protection Agency, 2000 Traverwood Road, Ann Arbor, MI 
48105, [email protected], (734) 214-4842; or, Rudy Kapichak, State 
Measures and Conformity Group, Transportation and Regional Programs 
Division, U.S. Environmental Protection Agency, 2000 Traverwood Road, 
Ann Arbor, MI 48105, [email protected], (734) 214-4574.

SUPPLEMENTARY INFORMATION: The contents of this preamble are listed in 
the following outline:

I. General Information
    A. Regulated Entities
    B. How Can I Get Copies of This Document?
    C. How and to Whom Do I Submit Comments?
    D. How Should I Submit CBI to the Agency?
    E. What Should I Consider as I Prepare My Comments for EPA?
II. Background on the Transportation Conformity Rule
    A. What Is Transportation Conformity?
    B. Why Is EPA Conducting This Rulemaking?
    C. Does This Proposal Include the Entire Transportation 
Conformity Regulation?
III. Conformity Grace Period and Revocation of the 1-Hour Ozone 
Standard
    A. When Will Conformity Apply for the 8-Hour Ozone and 
PM2.5 Standards?
    B. When Does Conformity Stop Applying for the 1-Hour Ozone 
Standard?
    C. When and for What Ozone Standard Does Conformity Apply in 
Areas With an Early Action Compact for the 8-Hour Ozone Standard?
IV. General Changes in Interim Emissions Tests
    A. Background
    B. Baseline Year Test for 8-Hour Ozone and PM2.5 
Areas
    C. Build/No-Build Test for Existing and New Nonattainment Areas
    D. Test Options for Ozone and CO Nonattainment Areas of Higher 
Classifications
V. Regional Conformity Tests in 8-Hour Ozone Areas That Do Not Have 
1-Hour Ozone SIPs
    A. What Are We Proposing?
    B. Why Are We Proposing These Options?
VI. Regional Conformity Tests in 8-Hour Ozone Areas That Have 1-Hour 
Ozone SIPs
    A. What Are We Proposing?
    B. Why Are We Proposing These Options?
VII. Regional Conformity Tests in PM2.5 Areas
    A. What Are We Proposing?
    B. Why Are We Proposing These Options?
VIII. Consideration of Direct PM2.5 and PM2.5 
Precursors in Regional Emissions Analyses
    A. What Are We Proposing?
    B. Why Are We Proposing These Options?
IX. Re-Entrained Road Dust in PM2.5 Regional Emissions 
Analyses
    A. Background
    B. What Are We Proposing?
    C. Why Are We Proposing These Options?
    D. Request for Comment on Estimating Road Dust Emissions
X. Construction-Related Fugitive Dust in PM2.5 Regional 
Emissions Analyses
    A. Background
    B. What Are We Proposing?
    C. Why Are We Proposing This Option?
    D. Implementation and Request for Additional Information
XI. Compliance With PM2.5 SIP Control Measures

[[Page 62691]]

    A. What Are We Proposing?
    B. Why Are We Proposing This Option?
XII. PM2.5 Hot-Spot Analyses
    A. What Are We Proposing?
    B. Existing Research on PM2.5 Hot-Spots and Request for 
Additional Information
    C. Why Are We Proposing These Options?
XIII. PM10 Hot-spot Analyses
    D. What Are We Proposing?
    E. Why Are We Considering These Options?
XIV. Miscellaneous Revisions for New and Existing Areas
    A. Definitions
    B. Areas with Insignificant Motor Vehicle Emissions
    C. Limited Maintenance Plans
    D. Grace Period for Transportation Modeling and Plan Content 
Requirements in Certain Ozone and CO Areas
    E. Minor Clarification to the List of PM10 Precursors
    F. Clarification of Requirements for Non-federal Projects in 
Isolated Rural Areas
    G. Use of Adequate and Approved Budgets in Conformity
XV. How Does Today's Proposal Affect Conformity SIPs?
XVI. Public Hearing
XVII. Statutory and Executive Order Reviews
    A. Executive Order 12866: Regulatory Planning and Review
    B. Paperwork Reduction Act
    C. Regulatory Flexibility Act
    D. Unfunded Mandates Reform Act
    E. Executive Order 13132: Federalism
    F. Executive Order 13175: Consultation and Coordination with Indian 
Tribal Governments
    G. Executive Order 13045: Protection of Children from Environmental 
Health and Safety Risks
    H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution or Use
    I. National Technology Transfer and Advancement Act

I. General Information

A. Regulated Entities

    Entities potentially regulated by the conformity rule are those 
that adopt, approve, or fund transportation plans, programs, or 
projects under title 23 U.S.C. or title 49 U.S.C. Regulated categories 
and entities affected by today's action include:

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                Category                  Examples of regulated entities
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Local government.......................  Local transportation and air
                                          quality agencies, including
                                          metropolitan planning
                                          organizations (MPOs).
State government.......................  State transportation and air
                                          quality agencies.
Federal government.....................  Department of Transportation
                                          (Federal Highway
                                          Administration (FHWA) and
                                          Federal Transit Administration
                                          (FTA)).
------------------------------------------------------------------------

    This table is not intended to be exhaustive, but rather provides a 
guide for readers regarding entities likely to be affected by this 
proposed rule. This table lists the types of entities of which EPA is 
aware that potentially could be regulated by the conformity rule. Other 
types of entities not listed in the table could also be regulated. To 
determine whether your organization is regulated by this action, you 
should carefully examine the applicability requirements in Sec.  93.102 
of the transportation conformity rule. If you have questions regarding 
the applicability of this action to a particular entity, consult the 
persons listed in the preceding FOR FURTHER INFORMATION CONTACT 
section.

B. How Can I Get Copies of This Document?

    1. Docket. EPA has established an official public docket for this 
action under Docket ID No. OAR-2003-0049. The official public docket 
consists of the documents specifically referenced in this action, any 
public comments received, and other information related to this action. 
Although a part of the official docket, the public docket does not 
include Confidential Business Information (CBI) or other information 
whose disclosure is restricted by statute. The official public docket 
is the collection of materials that is available for public viewing at 
the Air Docket in the EPA Docket Center, (EPA/DC) EPA West, Room B102, 
1301 Constitution Ave., NW., Washington, DC. The EPA Docket Center 
Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through 
Friday, excluding legal holidays. The telephone number for the Public 
Reading Room is (202) 566-1744, and the telephone number for the Air 
Docket is (202) 566-1742.
    2. Electronic Access. You may access this Federal Register document 
electronically through EPA's Transportation Conformity Web site at 
http://www.epa.gov/otaq/transp/traqconf.htm. You may also access this 
document electronically under the Federal Register listings at http://www.epa.gov/fedrgstr/.
    An electronic version of the public docket is available through 
EPA's electronic public docket and comment system, EPA Dockets. You may 
use EPA Dockets at http://www.epa.gov/edocket/ to submit or view public 
comments, access the index listing of the contents of the official 
public docket, and to access those documents in the public docket that 
are available electronically. Once in the system, select ``search,'' 
then key in the appropriate docket identification number.
    Certain types of information will not be placed in the EPA Dockets. 
Information claimed as CBI and other information for which disclosure 
is restricted by statute is not included in the official public docket 
and will not be available for public viewing in EPA's electronic public 
docket. EPA's policy is that copyrighted material will not be placed in 
EPA's electronic public docket but will be available only in printed, 
paper form in the official public docket. To the extent feasible, 
publicly available docket materials will be made available in EPA's 
electronic public docket. When a document is selected from the index 
list in EPA Dockets, the system will identify whether the document is 
available for viewing in EPA's electronic public docket. Although not 
all docket materials may be available electronically, you may still 
access any of the publicly available docket materials through the 
docket facility identified in section I.B.1. above. EPA intends to work 
towards providing electronic access in the future to all of the 
publicly available docket materials through EPA's electronic public 
docket.
    For public commenters, it is important to note that EPA's policy is 
that public comments, whether submitted electronically or in paper, 
will be made available for public viewing in EPA's electronic public 
docket as EPA receives them and without change, unless the comment 
contains copyrighted material, CBI, or other information for which 
disclosure is restricted by statute. When EPA identifies a comment 
containing copyrighted material, EPA will provide a reference to that 
material in the version of the comment that is placed in EPA's 
electronic public docket. The entire printed comment, including the

[[Page 62692]]

copyrighted material, will be available in the public docket.
    Public comments submitted on computer disks that are mailed or 
delivered to the docket will be transferred to EPA's electronic public 
docket. Public comments that are mailed or delivered to the docket will 
be scanned and placed in EPA's electronic public docket. Where 
practical, physical objects will be photographed, and the photograph 
will be placed in EPA's electronic public docket along with a brief 
description written by the docket staff.
    For additional information about EPA's electronic public docket 
visit EPA Dockets online or see 67 FR 38102, May 31, 2002.

C. How and to Whom Do I Submit Comments?

    You may submit comments electronically, by mail, by facsimile, or 
through hand delivery/courier. To ensure proper receipt by EPA, 
identify the appropriate docket identification number in the subject 
line on the first page of your comment. Please ensure that your 
comments are submitted within the specified comment period. Comments 
received after the close of the comment period will be marked ``late.'' 
Although EPA is not required to consider these late comments, we may do 
so as appropriate, considering time and volume constraints.
    1. Electronically. If you submit an electronic comment as 
prescribed below, EPA recommends that you include your name, mailing 
address, and an e-mail address or other contact information in the body 
of your comment. You should also include this contact information on 
the outside of any disk or CD ROM you submit, and in any cover letter 
accompanying the disk or CD ROM. This ensures that you can be 
identified as the submitter of the comment and allows EPA to contact 
you in case EPA cannot read your comment due to technical difficulties 
or needs further information on the substance of your comment. EPA's 
policy is that EPA will not edit your comment, and any identifying or 
contact information provided in the body of a comment will be included 
as part of the comment that is placed in the official public docket, 
and made available in EPA's electronic public docket. However, if EPA 
cannot read your comment due to technical difficulties and cannot 
contact you for clarification, EPA may not be able to further consider 
your comment.
    i. EPA Dockets. Your use of EPA's electronic public docket to 
submit comments to EPA electronically is EPA's preferred method for 
receiving comments. Go directly to EPA Dockets at http://www.epa.gov/edocket, and follow the online instructions for submitting comments. To 
access EPA's electronic public docket from the EPA Internet Home Page, 
select ``Information Sources,'' ``Dockets,'' and ``EPA Dockets.'' Once 
in the system, select ``search,'' and then key in Docket ID No. OAR-
2003-0049. The system is an ``anonymous access'' system, which means 
EPA will not know your identity, e-mail address, or other contact 
information unless you provide it in the body of your comment.
    ii. E-mail. Comments may be sent by electronic mail (e-mail) to [email protected], Attention Air Docket ID No. OAR-2003-0049. In 
contrast to EPA's electronic public docket, EPA's e-mail system is not 
an ``anonymous access'' system. If you send an e-mail comment directly 
to the docket without going through EPA's electronic public docket, 
EPA's e-mail system automatically captures your e-mail address. E-mail 
addresses that are automatically captured by EPA's e-mail system are 
included as part of the comment that is placed in the official public 
docket, and are thus made available in EPA's electronic public docket.
    iii. Disk or CD ROM. You may submit comments on a disk or CD ROM 
that you mail to the mailing address identified in section I.C.2. These 
electronic submissions will be accepted only in either WordPerfect or 
ASCII file format. Please avoid the use of special characters and any 
form of encryption, as this may adversely affect our ability to read 
these submissions.
    2. By Mail. Send two copies of your comments to: Air Docket, 
Environmental Protection Agency, Mailcode: 6102T, 1200 Pennsylvania 
Ave., NW., Washington, DC 20460, Attention Docket ID No. OAR-2003-0049.
    3. By Hand Delivery or Courier. Deliver two copies of your comments 
to: EPA Docket Center, Room B102, EPA West Building, 1301 Constitution 
Avenue, NW., Washington, DC, Attention Air Docket ID No. OAR-2003-0049. 
Such deliveries can only be accepted during the Docket's normal hours 
of operation as identified in Section I.B.1.
    4. By Facsimile. Fax your comments to: (202) 566-1741, Attention 
Docket ID No. OAR-2003-0049.

D. How Should I Submit CBI to the Agency?

    Do not submit information that you consider to be CBI 
electronically through EPA's electronic public docket or by e-mail. 
Send or deliver information identified as ``CBI only'' to the following 
address: Attention: Meg Patulski, State Measures and Conformity Group, 
Transportation and Regional Programs Division, U.S. Environmental 
Protection Agency, 2000 Traverwood Road, Ann Arbor, MI 48105, Docket ID 
No. OAR-2003-0049. You may claim information that you submit to EPA as 
CBI by marking any part or all of that information as CBI (if you 
submit CBI on disk or CD ROM, mark the outside of the disk or CD ROM as 
CBI and then identify electronically within the disk or CD ROM the 
specific information that is CBI). Information so marked will not be 
publicly disclosed except in accordance with procedures set forth in 40 
CFR part 2.
    In addition to one complete version of the comment that includes 
any information claimed as CBI, a copy of the comment that does not 
contain the information claimed as CBI must be submitted for inclusion 
in the public docket and EPA's electronic public docket. If you submit 
the copy that does not contain CBI on disk or CD ROM, mark the outside 
of the disk or CD ROM clearly indicating that it does not contain CBI. 
Information not marked as CBI will be included in the public docket and 
EPA's electronic public docket without prior notice. If you have any 
questions about CBI or the procedures for claiming CBI, please consult 
the person identified in the FOR FURTHER INFORMATION CONTACT section.

E. What Should I Consider as I Prepare My Comments for EPA?

    You may find the following suggestions helpful for preparing your 
comments:
    1. Explain your views as clearly as possible.
    2. Describe any assumptions that you used.
    3. Provide any technical information and/or data you used that 
support your views.
    4. If you estimate potential burden or costs, explain how you 
arrived at your estimate.
    5. Provide specific examples to illustrate your concerns.
    6. Offer alternatives.
    7. Make sure to submit your comments by the comment period deadline 
identified.
    8. To ensure proper receipt by EPA, identify the appropriate docket 
identification number in the subject line on the first page of your 
response. It would also be helpful if you provided the name, date, and 
Federal Register citation related to your comments.

[[Page 62693]]

II. Background on the Transportation Conformity Rule

A. What Is Transportation Conformity?

    Transportation conformity is required under Clean Air Act section 
176(c) (42 U.S.C. 7506(c)) to ensure that federally supported highway 
and transit project activities are consistent with (``conform to'') the 
purpose of the state air quality implementation plan (SIP). Conformity 
currently applies under EPA's rules to areas that are designated 
nonattainment, and those redesignated to attainment after 1990 
(``maintenance areas'' with plans developed under Clean Air Act section 
175A) for the criteria pollutants: ozone, coarse particulate matter 
(PM10), carbon monoxide (CO), and nitrogen dioxide 
(NO2). Today's proposal would also apply the conformity rule 
provisions in fine particulate matter (PM2.5) areas. 
Conformity to the purpose of the SIP means that transportation 
activities will not cause new air quality violations, worsen existing 
violations, or delay timely attainment of the relevant national ambient 
air quality standards (NAAQS or ``standards''). EPA's transportation 
conformity rule establishes the criteria and procedures for determining 
whether transportation activities conform to the SIP.
    EPA first promulgated the transportation conformity rule on 
November 24, 1993 (58 FR 62188), and subsequently published a 
comprehensive set of amendments on August 15, 1997 (62 FR 43780) that 
clarified and streamlined language from the 1993 rule. EPA has made 
other smaller amendments to the rule both before and after the 1997 
amendments.
    On June 30, 2003, EPA published a proposal that would amend the 
current conformity rule to be consistent with a March 2, 1999, U.S. 
Court of Appeals decision (68 FR 38974). The ``court proposal'' also 
included several proposed amendments to regulatory provisions that did 
not directly result from the court decision. EPA has not yet taken a 
final action on this proposed rulemaking. We are reviewing the public 
comments on the court proposal and will promulgate a final rule in the 
future.
    Today's proposal should be considered a separate action from the 
June 30, 2003 court proposal. However, some sections and paragraphs of 
the conformity rule are addressed in both proposals. For those 
sections, EPA has repeated the court proposal's regulatory language in 
today's proposal along with the proposed revisions that address the 
conformity requirements in 8-hour ozone and PM2.5 areas.
    Other changes to the conformity program could occur through the 
reauthorization of the Surface Transportation Act, currently entitled 
the Transportation Equity Act for the 21st Century (TEA-21). However, 
EPA believes it is prudent to expeditiously pursue the regulatory 
changes proposed today to ensure that entities subject to conformity 
for the new air quality standards understand applicable requirements as 
close to area designations as possible. EPA will continue to monitor 
the proposed reauthorization proposals for their potential impact on 
the conformity regulation. If statutory amendments to the conformity 
program result from TEA-21 reauthorization, EPA would take appropriate 
action to address such changes.
    EPA has consulted with the Department of Transportation (DOT), our 
federal partners in implementing the transportation conformity 
regulation, in developing this rulemaking, and DOT concurs with this 
proposal. EPA has also met with state and local transportation and 
environmental organizations to discuss this rulemaking. The proposal 
reflects our consideration of the comments that we received through 
these stakeholder discussions. Documentation of these stakeholder 
meetings and specific comments are included in the docket for this 
rulemaking.

B. Why Is EPA Conducting This Rulemaking?

    EPA has developed new 8-hour ozone and PM2.5 air quality 
standards, and anticipates designating areas as nonattainment for these 
new standards in April and December 2004, respectively. EPA is 
conducting this rulemaking to provide clear guidance and rules for 
implementing conformity for these standards. Some of the proposed 
revisions to the current regulation would provide more options and 
flexibility in demonstrating conformity. Other proposed changes would 
also apply to existing 1-hour ozone, CO, PM10 and 
NO2 nonattainment and maintenance areas.
    The following table provides a roadmap for determining whether a 
specific proposal included in this rulemaking would apply in your area.

----------------------------------------------------------------------------------------------------------------
                                Issue being addressed
         Type of area             in this proposal      Preamble  section       Proposed  regulatory  section
----------------------------------------------------------------------------------------------------------------
8-hour ozone.................  Conformity grace        III.A                Sec.   93.102(d).
                                period.
                               Revocation of 1-hour    III.B                No proposed regulatory amendments.
                                ozone standard.
                               Early Action Compacts.  III.C                No proposed regulatory amendments.
                               Baseline year test....  IV.B                 Sec.   93.119(b).
                               Build/no-build test     IV.C                 Sec.   93.119(b)(2).
                                (marginal and below                         Sec.   93.119(g)(2).
                                classifications and
                                subpart 1 areas).
                               Regional conformity     IV.D                 Sec.   93.119(b)(1).
                                tests (moderate and
                                above
                                classifications).
                               Regional Conformity     V                    Sec.   93.109(k).
                                tests (areas without
                                1-hour ozone budgets).
                               Regional conformity     VI                   Sec.   93.109(e).
                                tests (areas with 1-
                                hour ozone budgets.
                               Definitions...........  XIV.A.               Sec.   93.101.
                               Insignificance........  XIV.B                Sec.   93.109(d).
                                                                            Sec.   93.121(c).
                               Transportation plan     XIV.D                Sec.   93.106(b).
                                and modeling                                Sec.   93.122(c).
                                requirements
                                (moderate and above
                                classifications).
                               Non-federal projects    XIV.F                Sec.   93.121(b)(1).
                                (for isolated rural
                                areas only).
PM2.5........................  Applicability.........  III.A                Sec.   93.102(b)(1).
                               Conformity grace        III.A                Sec.   93.102(d)
                                period.
                               Baseline year test....  IV.B                 Sec.   93.119(e)
                               Build/no-build test...  IV.C                 Sec.   93.119(e)
                                                                            Sec.   93.119(g)(2)
                               Regional conformity     VII                  Sec.   93.109(i)
                                tests.

[[Page 62694]]

 
                               Precursors in regional  VIII                 Sec.   93.102(b)(2)
                                analyses.                                   Sec.   93.119(f)
                               Re-entrained road dust  IX                   Sec.   93.102(b)(3)
                                in regional analyses.                       Sec.   93.119(f)
                               Construction-related    X                    Sec.   93.122(f)
                                fugitive dust in
                                regional analyses.
                               Compliance with SIP     XI                   Sec.   93.117.
                                control measures.
                               Hot-spots.............  XII                  No proposed regulatory amendments.
                               Definitions...........  XIV.A                Sec.   93.101.
                               Insignificance........  XIV.B                Sec.   93.109(k).
                                                                            Sec.   93.121(c).
                               Non-federal projects    XIV.F                Sec.   93.121(b)(1).
                                (for isolated rural
                                areas only).
1-hour ozone.................  Revocation of 1-hour    III.B                No proposed regulatory amendments.
                                ozone standard.
                               Build/no-build test     IV.C                 Sec.   93.119(b)(2).
                                (marginal and below                         Sec.   93.119(g)(2).
                                classifications).
                               Regional conformity     IV.D                 Sec.   93.119(b)(1).
                                tests (moderate and
                                above
                                classifications).
                               Definitions...........  XIV.A                Sec.   93.101.
                               Insignificance........  XIV.B                Sec.   93.109(k)
                                                                            Sec.   93.121(c).
                               Limited maintenance     XIV.C                Sec.   93.101.
                                plans.                                      Sec.   93.109(j).
                                                                            Sec.   93.121(c).
                               Transportation plan     XIV.D                Sec.   93.106(b).
                                and modeling                                Sec.   93.122(c).
                                requirements
                                (moderate and above
                                classifications).
                               Non-federal projects    XIV.F                Sec.   93.121(b)(1).
                                (for isolated rural
                                areas only).
                               Clarification to use    XIV.G                Sec.   93.109(c).
                                of approved budgets
                                in conformity.
PM 10........................  Build/no-build test...  IV.C                 Sec.   93.119(d).
                                                                            Sec.   93.119(g)(2).
                               Compliance with SIP     XI                   No proposed regulatory amendments.
                                control measures
                                (Request for
                                information only).
                               Hot-spots.............  XIII                 No proposed regulatory amendments.
                               Clarification to        XIV.E                Sec.   93.102(b)(2).
                                Precursors.                                 Sec.   93.119(f)(5).
                               Definitions...........  XIV.A &              Sec.   93.101.
                               Insignificance........  XIV.B &              Sec.   93.109(k).
                                                                            Sec.   93.121(c).
                               Limited maintenance     XIV.C                Sec.   93.101.
                                plans.                                      Sec.   93.109(j).
                                                                            Sec.   93.121(c).
                               Non-federal projects    XIV.F                Sec.   93.121(b)(1).
                                (for isolated rural
                                areas only).
                               Clarification to use    XIV.G                Sec.   93.109(g).
                                of approved budgets
                                in conformity.
CO...........................  Build/no-build test     IV.C                 Sec.   93.119(c).
                                (lower CO                                   Sec.   93.119(g)(2).
                                classifications).
                               Regional conformity     IV.D                 Sec.   93.119(c)(1).
                                tests (higher CO
                                classifications).
                               Definitions...........  XIV.A                Sec.   93.101.
                               Insignificance........  XIV.B                Sec.   93.109(k).
                                                                            Sec.   93.121(c).
                               Limited maintenance     XIV.C                Sec.   93.101.
                                plans.                                      Sec.   93.109(j).
                                                                            Sec.   93.121(c).
                               Transportation plan     XIV.D                Sec.   93.106(b).
                                and modeling                                Sec.   93.122(c).
                                requirements
                                (moderate and serious
                                classifications).
                               Non-federal projects    XIV.F                Sec.   93.121(b)(1).
                                (for isolated rural
                                areas only).
                               Clarification to use    XIV.G                Sec.   93.109(f).
                                of approved budgets
                                in conformity.
NO2..........................  Build/no-build test...  IV.C                 Sec.   93.119(d).
                                                                            Sec.   93.119(g)(2).
                               Definitions...........  XIV.A                Sec.   93.101.
                               Insignificance........  XIV.B                Sec.   93.109(k).
                                                                            Sec.   93.121(c).
                               Non-federal projects    XIV.F                Sec.   93.121(b)(1).
                                (for isolated rural
                                areas only).
                               Clarification to use    XIV.G                Sec.   93.109(h).
                                of approved budgets
                                in conformity.
----------------------------------------------------------------------------------------------------------------

This table illustrates which parts of the proposal are relevant for 
various pollutants and standards. Please note that Sections V.-VII. 
provide stand-alone descriptions of the proposed emissions tests for 
PM2.5 areas and 8-hour ozone areas with and without existing 
1-hour ozone SIPs. For example, if your area expects only to be 
designated nonattainment under the PM2.5 standard, you 
should read section VII. but not sections V. and VI (for 8-hour ozone 
areas). EPA believes that any redundancy between these sections

[[Page 62695]]

is warranted to assist readers who may not need to read the entire 
proposal.

C. Does This Proposal Include the Entire Transportation Conformity 
Regulation?

    No. The proposed regulatory text is limited to proposed changes to 
affected portions of the conformity rule. However, a complete version 
of the conformity rule is available to the public on our transportation 
conformity website listed in Section I.B.2. of this proposal. The 
complete version is intended to help reviewers understand today's 
proposed changes in context with the June 30, 2003 conformity proposal 
and other existing rule sections that are not proposed to be changed.

III. Conformity Grace Period and Revocation of the 1-Hour Ozone 
Standard

A. When Will Conformity Apply for the 8-Hour Ozone and PM2.5 
Standards?

    Conformity applies one year after the effective date of EPA's 
initial nonattainment designation for a given pollutant and standard. 
This one-year conformity grace period is provided by Clean Air Act 
section 176(c)(6) and Sec.  93.102(d) of the conformity regulation.
    Section 93.102(d) currently addresses newly designated 
nonattainment areas for ozone, CO, PM10 and NO2. 
This proposal would add PM2.5 to Sec.  93.102(d) of the 
conformity rule even though the grace period is already available to 
all newly designated nonattainment areas as a matter of law. Today's 
proposed change would simply reflect the statutory flexibility in the 
regulation.
    Although the same pollutant, the 8-hour and 1-hour ozone standards 
are different NAAQS. Therefore, every area that is designated 
nonattainment for the 8-hour ozone standard will also have a 1-year 
grace period before conformity applies for that standard, even if the 
area was designated nonattainment for the 1-hour ozone standard. Areas 
currently subject to conformity for the 1-hour ozone standard would 
continue to be subject to such requirements during the 1-year grace 
period for the 8-hour ozone standard. EPA anticipates designating areas 
for the 8-hour ozone standard in April 2004. If, for example, 
designations have a 30-day delayed effective date, conformity for the 
8-hour ozone standard would begin to apply in May 2005, since under 
EPA's regulations the one-year grace period begins upon the effective 
date of an area's designation. EPA is proposing to include new 
regulatory definitions for the 1-hour and 8-hour ozone standards in 
Sec.  93.101. These proposed definitions are consistent with how the 
standards are described in existing EPA regulations at 40 CFR 50.9 and 
40 CFR 50.10, respectively.
    Similarly, every area that is designated nonattainment for the 
PM2.5 standard will have a one-year grace period before 
conformity applies for that standard. EPA plans to designate areas for 
PM2.5 by December 2004. Under today's proposed Sec.  
93.102(b), the conformity rule would apply in areas designated 
nonattainment for PM2.5. Therefore, conformity for the 
PM2.5 standard would apply beginning in January 2006, for 
example, if a 30-day effective date is provided in accordance with 
Sec.  93.102(d). It is important to note that PM10 is a 
different pollutant than PM2.5, and today's proposal does 
not affect the applicability and general implementation of conformity 
in PM10 nonattainment and maintenance areas.
    EPA anticipates that some areas will be designated as nonattainment 
for both the 8-hour ozone and PM2.5 standards. In these 
areas, conformity for the 8-hour ozone standard will apply one year 
after the effective date of the area's 8-hour ozone designation, while 
conformity for PM2.5 will apply one year after the effective 
date of the area's PM2.5 designation.
    The following discussion provides more details on the application 
of the one-year conformity grace period in specific types of newly 
designated nonattainment areas--metropolitan, donut, and isolated rural 
areas.
1. Metropolitan Areas
    Metropolitan areas are urbanized areas that have a population 
greater than 50,000 and a designated metropolitan planning organization 
(MPO) responsible for transportation planning per 23 U.S.C. 134. In 
general, within one year after the effective date of the initial 
nonattainment designation for a given pollutant and standard, the 
area's MPO and DOT must make a conformity determination with regard to 
that pollutant and standard for the area's transportation plan and TIP. 
If, at the conclusion of the one-year grace period, the MPO and DOT 
have not made a plan and TIP conformity determination for the relevant 
pollutant and standard, the area would be in a conformity ``lapse.'' As 
described in section III.B., MPOs must continue to meet conformity 
requirements for the 1-hour ozone standard for plan, TIP, and project 
approvals made up until the time that the 1-hour standard is revoked.
    During a conformity lapse, only certain projects can receive 
additional federal funding or approvals to proceed. Such projects 
include: exempt projects (e.g., safety projects) listed in Sec. Sec.  
93.126, 93.127 and 93.128 of the current conformity rule; 
transportation control measures in an approved SIP; and, projects or 
project phases (e.g., right-of-way, final design, construction) that 
received all required federal funding or approval prior to the 
conformity lapse. The practical impact of a conformity lapse will vary 
on an area-by-area basis. For additional information on projects that 
can proceed during a conformity lapse, see the following guidance 
memoranda that implement the March 2, 1999 U.S. Court of Appeals 
decision that affected related provisions of the conformity rule: DOT's 
January 2, 2002 guidance, published in the Federal Register on February 
7, 2002 (67 FR 5882); DOT's May 20, 2003, and FTA's April 9, 2003, 
supplemental guidance documents; as well as EPA's May 14, 1999 guidance 
memorandum. EPA proposed to incorporate this existing guidance into the 
conformity regulation on June 30, 2003 (68 FR 38974). A copy of this 
proposed rulemaking, as well as the guidance listed above, can be 
downloaded from EPA's transportation conformity Web site listed in 
section I.B.2. of this proposal.
2. Donut Areas
    For the purposes of conformity, a ``donut'' area is the geographic 
area outside a metropolitan planning area boundary, but inside a 
designated nonattainment or maintenance area boundary that includes an 
MPO. The conformity requirements for donut areas, including the 
application of the one-year conformity grace period, are generally the 
same as those for metropolitan areas. Within one year after the 
effective date of an area's initial nonattainment designation, the 
existing and planned transportation network for the donut portion of 
the area (as well as for the metropolitan portion of the area) must 
demonstrate conformity, or conformity of the metropolitan 
transportation plan and TIP will lapse as discussed above, and the 
entire nonattainment area will be unable to obtain additional project 
funding and approvals at that time.
    To demonstrate conformity of its plan and TIP, the adjacent MPO 
must include in its regional emissions analysis the emissions from the 
donut area's proposed transportation network and planned project 
activities. To demonstrate conformity of projects in the donut portion, 
such projects must have been included in the regional emissions 
analysis that supports the conformity determination of the metropolitan 
area's plan and TIP. In nonattainment and maintenance areas with a 
donut portion, the MPO and

[[Page 62696]]

State DOT may choose to include donut area projects in the MPO's plan 
and TIP. However, this approach is not required by either DOT's 
planning regulations or the conformity rule.
    The interagency consultation group for each newly designated 
nonattainment area that includes a donut portion should determine how 
best to consider the donut area transportation system and new donut 
area projects in the MPO's regional emissions analyses and conformity 
determinations. For more discussion on how conformity determinations 
should be made for donut areas, see the preamble to the original 
conformity rule published on November 24, 1993 (58 FR 62207).
3. Isolated Rural Areas
    Isolated rural nonattainment and maintenance areas are areas that 
do not contain or are not part of any metropolitan planning area as 
designated under 23 U.S.C. 134 and 49 U.S.C. 5303. Isolated rural areas 
do not have metropolitan transportation plans or TIPs required under 23 
U.S.C. 134 and 49 U.S.C. 5303 and 5304 for any portion of the area, and 
do not have projects that are part of the emissions analysis of any 
MPO's metropolitan transportation plan or TIP. Projects in such areas 
are instead included only in statewide transportation improvement 
programs (STIPs) and statewide transportation plans, when appropriate.
    Like all newly designated nonattainment areas, the one-year 
conformity grace period will begin on the effective date of an isolated 
rural area's initial nonattainment designation. However, because these 
areas do not have federally required metropolitan transportation plans 
and TIPs, they are not subject to the frequency requirements for 
conformity determinations on plans and TIPs specified in Sec.  
93.104(b), (c) and (e) of the current rule. Instead, conformity 
determinations in isolated rural areas are required only when a non-
exempt FHWA/FTA project(s) needs funding or approval. Therefore, 
although the one-year conformity grace period is available to isolated 
rural areas, no conformity consequences may apply upon the expiration 
of the one-year grace period because these areas may not have any 
projects that require funding and approval at that time.
    In fact, many isolated rural areas may not have a transportation 
project in need of federal funding or approval for some time after the 
one-year grace period has ended, and therefore, will not have to 
demonstrate conformity before that time. Once the conformity grace 
period has expired, a conformity determination will only be required in 
such areas the next time a non-exempt project needs funding or 
approval. For non-exempt FHWA/FTA projects, a conformity determination 
is normally required before the National Environmental Policy Act 
(NEPA) process is completed, since NEPA is typically the first stage 
requiring approval in a federal project's development. However, 
isolated rural areas that are newly designated as nonattainment may 
also be required to demonstrate conformity for subsequent funding and 
approvals for project phases (e.g., right-of-way acquisition, final 
design, construction) that occur after the grace period has ended, if 
these projects have not yet been included in a conformity determination 
and regional emissions analysis for the relevant pollutant and 
standard. For more information on the conformity requirements for 
isolated rural areas, see Sec.  93.109(g) of the current conformity 
regulation; corresponding discussions on how to demonstrate conformity 
in isolated rural areas can also be found in the preambles to the 
November 24, 1993 transportation conformity final rule (58 FR 62207) 
and the August 15, 1997 final rule (62 FR 43785). Please note that the 
current rule's Sec.  93.109(g) would become Sec.  93.109(l) under 
today's proposal, due to other proposed revisions and additions to this 
regulatory section. The proposed changes to Sec.  93.109 do not change 
the basic conformity requirements for isolated rural areas.

B. When Does Conformity Stop Applying for the 1-Hour Ozone Standard?

    EPA proposed in a separate rulemaking to revoke the 1-hour ozone 
standard--in whole or in part--one year after the effective date of 
EPA's 8-hour ozone standard designations (June 2, 2003, 68 FR 32819). 
Today's conformity proposal is consistent with the revocation options 
in the June 2003 proposal, but does not seek additional comment on the 
proposed revocation options.
    Clean Air Act section 176(c)(5) requires conformity only in areas 
that are designated nonattainment or maintenance for a given pollutant 
and standard. Therefore, under either of the revocation options in 
EPA's proposed 8-hour ozone implementation rule, conformity for the 1-
hour ozone standard would no longer apply in existing 1-hour ozone 
nonattainment and maintenance areas once the standard and area 
designations are revoked. The proposed one-year delay in the revocation 
of the 1-hour ozone standard is linked to the one-year statutory 
conformity grace period for newly designated 8-hour ozone nonattainment 
areas. To preserve the progress that areas have made in achieving clean 
air to date, EPA believes that 1-hour ozone nonattainment and 
maintenance areas should continue to ensure that transportation 
activities conform to the existing 1-hour ozone standard until 
conformity for the new 8-hour ozone standard applies.
    During the one-year grace period, areas that are currently subject 
to the 1-hour ozone standard must continue to adhere to 1-hour 
conformity requirements. Additionally, areas should consider at what 
point they will determine conformity for the 8-hour ozone standard. For 
example, if a conformity determination is made in June 2004, an area 
may choose to demonstrate conformity for the 1-hour ozone standard and 
address the 8-hour ozone standard at a later date near the end of the 
one-year grace period. In contrast, if a conformity determination is 
made in January 2005, an area may choose to demonstrate conformity for 
both ozone standards because of the approaching end of the one-year 
grace period.
    Under EPA's June 2003 implementation proposal, when the 1-hour 
standard is revoked, conformity would no longer apply for either ozone 
standard in areas that are attaining the 8-hour ozone standard. See 
EPA's proposed 8-hour implementation rule for more discussion on the 
proposed options for revoking the 1-hour ozone standard (June 2, 2003; 
68 FR 32818-32825).

C. When and for What Ozone Standard Does Conformity Apply in Areas With 
an Early Action Compact for the 8-Hour Ozone Standard?

    Areas that are violating the 8-hour ozone standard but are 
attaining the 1-hour ozone standard--including 1-hour ozone maintenance 
areas--were eligible for an Early Action Compact (EAC) as described in 
EPA's November 14, 2002 memorandum entitled, ``Schedule for 8-Hour 
Ozone Designations and its Effect on Early Action Compacts'' and EPA's 
June 2, 2003 proposal for the implementation of the 8-hour ozone 
standard (68 FR 32859-32860).
    For areas participating in an EAC, EPA plans to provisionally defer 
the effective date of the area's 8-hour ozone nonattainment designation 
into the future. The deferral of the 8-hour designation effective date 
is contingent upon the participating area's adherence to all the terms 
and milestones of its EAC. If the EAC area attains the 8-hour

[[Page 62697]]

ozone standard by December 2007, EPA would take action in Spring 2008 
to end the deferred nonattainment designation effective date and 
replace it with an attainment designation that would become effective 
shortly thereafter. If, however, an area misses a key EAC milestone, 
the November 14, 2002 memorandum states that EPA would retract its 
deferral, and the nonattainment designation would be effective shortly 
after the missed milestone. Neither today's proposal nor the June 2, 
2003 rulemaking take comment on the EAC program itself.
    A deferred effective date for 8-hour ozone designations in areas 
that opted into an EAC has certain implications for when conformity 
applies for both the 8-hour and 1-hour ozone standards. Consistent with 
the current conformity rule Sec.  93.102(d) and Clean Air Act section 
176(c)(6), conformity for the 8-hour ozone standard would not apply 
until one year after the effective date of an EAC area's 8-hour 
nonattainment designation. Therefore, conformity for the 8-hour ozone 
standard would apply in an EAC area only if the area fails to meet all 
the terms and milestones of its compact and the nonattainment 
designation becomes effective. In this case, conformity for the 8-hour 
standard would be required one year after the effective date of EPA's 
nonattainment designation that would occur shortly after a missed EAC 
milestone. Conversely, if the area meets all of the EAC milestones and 
attains the 8-hour ozone standard by December 2007, conformity for the 
8-hour ozone standard would never apply since the area's ultimate 
effective designation would be attainment for the 8-hour ozone 
standard.
    Conformity for the 1-hour ozone standard will continue to apply in 
EAC areas that are currently 1-hour ozone maintenance areas, and 
therefore are required to demonstrate conformity for that standard. For 
these areas, the effective date of 8-hour designations would be 
deferred and the 1-hour standard would not be revoked. If a maintenance 
area meets all of its EAC milestones and attains the 8-hour ozone 
standard by December 2007, conformity for the 1-hour standard would no 
longer apply once EPA revokes that standard one year after the 
effective date of EPA's 8-hour attainment designation (i.e., Spring 
2009).
    If, however, a 1-hour ozone maintenance area fails to meet a 
milestone in its EAC, EPA would remove its deferral of the effective 
date and the area's 8-hour ozone nonattainment designation would become 
effective shortly after the missed milestone. Under this scenario, 
conformity for the 1-hour ozone standard would continue to apply for 
one year after the effective date of EPA's nonattainment designation, 
at which time the 1-hour ozone standard would be revoked, the one-year 
conformity grace period would expire and conformity for the 8-hour 
ozone standard would begin to apply.

IV. General Changes in Interim Emissions Tests

A. Background

    Conformity determinations for transportation plans and TIPs as well 
as transportation projects not from a conforming plan and TIP must 
include a regional emissions analysis that fulfills certain Clean Air 
Act provisions. Section 176(c) requires that transportation activities 
in nonattainment and maintenance areas must not worsen air quality. In 
addition, transportation activities in ozone and CO areas of higher 
nonattainment classifications need to contribute emission reductions 
towards attainment.
    The conformity rule provides for several different regional 
emissions analysis tests that satisfy these Clean Air Act requirements 
in different situations. Once a SIP with a motor vehicle emissions 
budget (``budget'') is submitted for an air quality standard and EPA 
finds the budget adequate or approves it as part of the SIP, conformity 
is demonstrated using the budget test for that pollutant or precursor, 
as described in Sec.  93.118 of the conformity rule. Before an adequate 
or approved SIP budget is available, conformity of the transportation 
plan, TIP, or project not from a conforming plan and TIP is 
demonstrated with the interim emissions tests, as described in Sec.  
93.119.
    Today's proposal outlines several options for completing regional 
emissions analyses for the new standards before SIP budgets for these 
standards are available. According to EPA's proposed implementation 
rule (June 2, 2003, 68 FR 32830-32837), 8-hour ozone nonattainment 
areas of moderate and above classifications and some areas designated 
under Clean Air Act subpart 1 would have two or three years from the 
effective date of designations to submit a SIP (either for attainment 
or reasonable further progress) with budgets for that standard. Areas 
classified as marginal and some areas designated under subpart 1 (those 
with early attainment dates) may not have 8-hour ozone SIP budgets for 
some time, since their attainment dates would be relatively soon after 
the date of their 8-hour ozone designations. These areas would only 
have 8-hour ozone SIP budgets if they voluntarily submitted a control 
strategy SIP or submitted a maintenance plan for redesignation. In 
addition, EPA currently anticipates that PM2.5 nonattainment 
areas would submit a SIP with budgets within three years of 
PM2.5 nonattainment designations.
    Therefore, as proposed, conformity would likely apply in all 8-hour 
ozone and PM2.5 nonattainment areas before SIP budgets for 
the new standards are available, and during this time period, interim 
emissions tests would be used for conformity determinations. It is 
important to note that EPA has historically called such tests the 
``emission reduction tests.'' However, since the actual reduction of 
emissions would not always be required in many areas (as described 
below and in proposed Sec.  93.119), EPA is proposing to change 
``emission reduction test'' to ``interim emissions test'' throughout 
the conformity regulation.
    The following paragraphs generally describe the proposed changes to 
the interim emissions tests (under Sec.  93.119). Sections V., VI., and 
VII. describe the application of these tests in different 8-hour ozone 
and PM2.5 areas (under Sec.  93.109).

B. Baseline Year Test for 8-Hour Ozone and PM2.5 Areas

1. What Are We Proposing?
    We are proposing to add the following tests to the conformity rule 
for use in 8-hour ozone and PM2.5 nonattainment areas:
    [sbull] The ``less-than-2002 emissions'' test, and
    [sbull] The ``no-greater-than-2002 emissions'' test.
Under these interim emissions tests, conformity would be demonstrated 
if the emissions from the proposed transportation system are less than 
or no greater than 2002 motor vehicle emissions in a given area. 
Proposed regulatory text for the 2002 baseline year tests can be found 
in Sec.  93.119. See Sections V.-VII. for how these tests are proposed 
to be applied in 8-hour ozone and PM2.5 areas.
    Although today's action proposes no substantive change to the 1990 
baseline year tests for existing areas, Sec.  93.119 has been 
reorganized to also include the provisions for new 8-hour ozone and 
PM2.5 areas.
2. Why Are We Proposing These Changes?
    EPA believes that the year 2002 is more appropriate than the year 
1990 in

[[Page 62698]]

meeting Clean Air Act provisions in new 8-hour ozone and 
PM2.5 areas. Under the statute, transportation activities in 
nonattainment and maintenance areas cannot increase the frequency or 
severity of air quality violations. EPA selected the year 1990 as the 
baseline year for nonattainment areas under the existing standards, 
since that was the baseline year for many requirements in the Clean Air 
Act Amendments of 1990, including the base year for SIP inventories. It 
was also the year that the relevant Clean Air Act legislation was 
enacted.\1\ However, 1990 has little relevance as a baseline year for 
emissions under the new standards.
---------------------------------------------------------------------------

    \1\ Please note that PM10 areas can use an alternate 
baseline year for conformity if the applicable SIP is based on a 
baseline inventory from a different calendar year (40 CFR 
93.119(c)(2)). EPA is not proposing to offer an alternate baseline 
year for PM2.5 areas since all PM2.5 areas 
should be establishing 2002 baseline SIP inventories.
---------------------------------------------------------------------------

    Therefore, EPA has preliminarily selected 2002 as the baseline year 
for SIP inventories under the new 8-hour ozone and PM2.5 
standards. EPA's November 18, 2002 memorandum, ``2002 Base Year 
Emission Inventory SIP Planning: 8-hr Ozone, PM2.5, and 
Regional Haze Programs,'' identifies 2002 as the anticipated emission 
inventory base year for the SIP planning process to address both of 
these pollutants and standards. In addition, EPA's 8-hour ozone 
implementation rule proposes 2002 as the base year for 8-hour ozone SIP 
inventories (June 2, 2003, 68 FR 32810). The 2002 SIP inventories would 
provide the baseline level of motor vehicle emissions in 2002 to 
complete either proposed baseline year test. In addition, EPA's memo 
explains that ``the selection of 2002 harmonizes dates for other 
reporting requirements, e.g., EPA's Consolidated Emissions Reporting 
Rule (CERR) that requires submission of emission inventories every 
three years; 2002 is one of the required years for such updates.'' 
Therefore, coordinating conformity's baseline with other data 
collection and inventory requirements would allow state and local 
governments to use their resources more efficiently.
    Under Sec.  93.105(c)(1)(i) of the current rule, the interagency 
consultation process would be used to determine the latest assumptions 
and models for generating 2002 motor vehicle emissions to complete 
either baseline year test. In general, the 2002 baseline year test can 
be completed with the baseline year SIP's 2002 motor vehicle emissions 
inventory, if the SIP has been submitted in time for the current 
conformity determination. If the SIP has not been submitted, conformity 
could be completed using draft 2002 baseline year emissions from a SIP 
inventory under development. Alternatively, an MPO, in consultation 
with state and local air agencies, could develop 2002 baseline year 
emissions as part of the conformity analysis. Whatever the source, the 
2002 baseline year emissions level that is used in conformity must be 
based on the latest planning assumptions available for the year 2002, 
the latest emissions model, and appropriate methods for estimating 
travel and speeds as required by Sec. Sec.  93.110, 93.111 and 93.122 
of the current conformity rule.

C. Build/No-Build Test for Existing and New Nonattainment Areas

1. What Are We Proposing?
    EPA is proposing a revised build/no-build test for certain existing 
and new nonattainment areas. Under the current rule, conformity is 
demonstrated with the ``build-less-than-no-build'' test for all ozone, 
CO, PM10, and NO2 areas. The proposal would amend 
Sec.  93.119 to create the ``build-no-greater-than-no-build'' test, 
where conformity would be met if emissions from the proposed 
transportation system (``build'') were less than or equal to emissions 
from the existing transportation system (``no-build'').
    Under this proposal, the build-no-greater-than-no-build test would 
be available to the following subset of new and existing areas:
    [sbull] 8-hour ozone areas of marginal and below classifications,
    [sbull] 8-hour ozone areas designated nonattainment under Clean Air 
Act subpart 1,
    [sbull] All PM2.5 areas,
    [sbull] 1-hour ozone areas of marginal and below classifications,
    [sbull] CO areas of moderate classification with design values less 
than 12.7 ppm,
    [sbull] Not classified CO areas,
    [sbull] All PM10 areas, and
    [sbull] All NO2 areas.

Sections V., VI., and VII. of this proposal provide more detail 
regarding the application of the build/no-build test in various 8-hour 
ozone and PM2.5 areas.
    For areas that would be using the build-no-greater-than-no-build 
test, EPA is also proposing to modify Sec.  93.119(e) of the current 
rule so that a regional emissions analysis would not be necessary for 
future analysis years where the build (or ``action'' scenario) and no-
build (or ``baseline'' scenario) contain exactly the same 
transportation projects and planning assumptions, for the reasons 
described below. Such a case may occur in smaller areas that do not 
have projects planned for later years in the regional emissions 
analysis, and population, land use, economic, and other assumptions do 
not change between the build and no-build scenarios for those years. 
Under this proposal, a regional emissions analysis would continue to be 
required for applicable years where the action and baseline scenarios 
contain different projects and assumptions.
    This proposed change can be found in Sec.  93.119(g)(2) of the 
proposed regulatory text. This proposal would require that the 
conformity determination include documentation that a regional 
emissions analysis is not completed for analysis years in which no new 
projects are proposed and no change in planning assumptions has 
occurred.
    Finally, Sec.  93.119 is being reorganized in general to 
accommodate the above and other changes articulated in this proposal 
for new and existing areas.
2. Why Are We Proposing These Changes?
    EPA believes that changing the build/no-build test for certain 
areas is consistent with Clean Air Act section 176(c)(3)(A)(iii) which 
specifically requires that transportation plans and TIPs contribute to 
annual emissions reductions only in the higher classifications of ozone 
and CO areas. This statutory provision does not apply to any other type 
of nonattainment area.
    Instead, all other areas must demonstrate only that transportation 
activities do not cause or contribute to new violations, increase the 
frequency or severity of existing violations, or delay timely 
attainment, pursuant to Clean Air Act section 176(c)(1)(B). EPA 
believes that if the ``build'' is no greater than (i.e., less than or 
equal to) the ``no-build,'' that such a demonstration is made, since 
only an increase in emissions would worsen air quality.
    This change to the build/no-build test would make its 
implementation consistent with the implementation of the baseline year 
tests: in ozone and CO areas of higher classifications, expected 
emissions from the proposed transportation system must be less than 
emissions in the baseline year, while in all other areas, expected 
emissions must be no greater than emissions in the baseline year. For 
further discussion of the rationale for how and where the baseline year 
tests apply, please refer to the preamble to the January 11, 1993 
proposed rule (58 FR 3782-3784) and the preamble to the July 9, 1996 
proposed rule (61 FR 36116-36117).
    Today's proposal would provide flexibility to certain areas by 
allowing

[[Page 62699]]

emissions from the proposed transportation system to be less than or 
equal to the emissions from the current system, rather than requiring 
an actual reduction in emissions as is required for ozone and CO areas 
with higher classifications. Where the Clean Air Act does not require 
such emission reductions, EPA believes that if transportation 
activities can be found to conform by producing no adverse impacts on 
the number and severity of air quality violations, such a demonstration 
would be consistent with the Clean Air Act requirements.
    The proposal would also reduce the resource burden for analysis 
years where no new projects are proposed to be completed and 
assumptions do not change. Under the current rule, a regional emissions 
analysis is required for all analysis years, even if no new projects 
are proposed for analysis years in the distant future. For such 
analysis years, the emissions from the build and no-build scenarios 
contain the same projects and assumptions, and therefore, result in 
exactly the same level of emissions.
    One may argue that it would be obvious that the build-no-greater-
than-no-build test is passed without calculating the emissions for such 
analysis years. Furthermore, the Clean Air Act requirement to not 
worsen air quality may be met by documenting in the conformity 
determination that projects, assumptions, and thus emissions would 
remain the same for affected analysis years. On the other hand, one may 
argue that a build/no-build regional analysis should still be completed 
for all analysis years to inform long-term transportation and air 
quality planning. However if such information is deemed appropriate, 
analyses could still be done voluntarily. EPA requests comment on this 
proposed change to the build/no-build analysis year requirements.

D. Test Options for Ozone and CO Nonattaintment Areas of Higher 
Classifications

1. What Are We Proposing?
    EPA is proposing three options that would affect regional emissions 
analyses before adequate or approved SIP budgets are established in 
ozone and CO areas of higher nonattainment classifications. Under the 
current rule, these areas are required to complete both the build-less-
than-no-build and less-than-baseline year tests when a conformity 
determination is completed during this time period. This proposal would 
affect moderate and above 1-hour and 8-hour ozone areas, moderate CO 
areas with design values greater than 12.7ppm, and serious CO areas.
    EPA requests comment on the following proposed options for these 
areas:
    (1) Complete both the build-less-than-no-build and less-than-
baseline year tests;
    (2) Complete either the build-less-than-no-build or less-than-
baseline year test; or
    (3) Require that only one of these tests be met and eliminate the 
second test as an option altogether.

    The proposed regulatory text in Sec.  93.119(b)(1) reflects the 
first option, although EPA could finalize any one of the three proposed 
options.
    The first option would retain the current conformity rule 
requirement that such areas use both the current build-less-than-no-
build test and the less-than-baseline year test. Under this option, 
emissions from the proposed transportation system (build) would have to 
be less than emissions from the existing system (no build) and less 
than emissions in 1990 (for higher classification 1-hour ozone and CO 
areas) or 2002 (for higher classification 8-hour ozone areas).
    The second proposed option would allow these areas to choose 
between the current build-less-than-no-build test and the less-than-
baseline year test (either 1990 or 2002, as applicable). The final 
option would require only one test in these areas while eliminating the 
second test as an option altogether. For example, this option could 
require the less-than-baseline year test and delete the build/no-build 
test from the conformity rule as an option for affected areas.
2. Why Are We Proposing These Options?
    EPA is interested in exploring alternatives in an effort to provide 
the most flexible and least burdensome way of meeting statutory 
requirements. When EPA first promulgated the transportation conformity 
rule (January 11, 1993, 58 FR 3782), EPA determined that moderate and 
above 1-hour ozone areas and CO areas of higher classifications would 
have to meet both the build-less-than-no-build test and the less-than-
baseline year test to satisfy both statutory requirements that 
transportation planning activities not cause or contribute to 
violations of the standards (Clean Air Act section 176(c)(1)(B)) and 
that such activities contribute to annual emissions reductions (Clean 
Air Act section 176(c)(3)(A)(iii)).
    The current conformity rule requires higher classification ozone 
and CO areas to meet both of these tests in the absence of an adequate 
or approved SIP budget (option 1). For the same reasons described in 
previous rulemakings,\2\ EPA proposes as its first option to continue 
these same requirements for current 1-hour ozone and CO and new 8-hour 
ozone nonattainment areas with higher classifications. EPA believes 
that the current conformity rule would continue to assist areas in 
meeting Clean Air Act requirements.
---------------------------------------------------------------------------

    \2\ January 11, 1993, proposed conformity rule (58 FR 3782-3784) 
and the July 9, 1996, proposed rule (61 FR 36116-36117).
---------------------------------------------------------------------------

    However, ten years of experience in implementing the conformity 
rule has caused EPA to consider whether either the build-less-than-no-
build test or less-than-baseline year test (option 2) may also be 
sufficient to meet both the statutory requirements that transportation 
activities not contribute to violations and contribute to emissions 
reductions. First, the build-less-than-no-build test may by itself 
demonstrate that emissions from the proposed transportation plan would 
be lower than projected future emissions from the existing planned 
transportation system, since the build scenario must be less than the 
no-build scenario. Thus, one might conclude that emissions from the 
proposed transportation plan contribute to emissions reductions and may 
not cause or contribute to new violations of the ozone standard.
    Alternatively, if emissions are reduced from baseline year levels, 
then one might conclude that air quality would not be worsened from 
current levels. The less-than-baseline year test by itself might also 
demonstrate that implementation of the proposed transportation system 
may produce actual emissions reductions from the motor vehicle emission 
baseline year, since emissions must be less than or reduced from the 
baseline year. Thus, by using only the less-than-baseline year test, 
the transportation plan may both contribute to emissions reductions and 
not itself produce emissions that could cause or contribute to any 
violations. EPA requests comment on this alternative of offering a 
choice between the build-less-than-no-build and less-than-baseline year 
tests to meet both statutory conformity requirements, for ozone areas 
and CO areas of higher classifications.
    Further, EPA proposes a third option that such areas be required to 
meet only one interim emissions test while eliminating the other 
interim emissions test as an option altogether. As described above for 
option 2, if it can be concluded that either test is sufficient

[[Page 62700]]

for meeting statutory requirements, then retaining only one test in the 
conformity regulation would also meet the statute. EPA requests comment 
on this alternate proposal.

V. Regional Conformity Tests in 8-Hour Ozone Areas That Do Not Have 1-
Hour Ozone SIPs

A. What Are We Proposing?

    EPA is proposing several options for completing regional emissions 
analyses in 8-hour ozone areas that do not have an existing 1-hour 
ozone SIP with applicable budgets. These 8-hour ozone areas either were 
never designated nonattainment under the 1-hour ozone standard or were 
1-hour ozone nonattainment areas that for various reasons never 
submitted a control strategy SIP or maintenance plan with approved or 
adequate motor vehicle emissions budgets. A regional emissions analysis 
is the part of a conformity determination that assesses whether the 
emissions produced by transportation activities are consistent with 
state and local air quality goals.
1. Conformity After 8-Hour Ozone SIP Budgets Are Adequate or Approved
    Once a SIP for the 8-hour ozone standard is submitted with a 
budget(s) that EPA has found adequate or approved, the budget test 
would be used in accordance with Sec.  93.118 to complete all 
applicable regional emissions analyses. Conformity would be 
demonstrated if the transportation system emissions reflecting the 
proposed transportation plan, TIP, or project not from a conforming 
plan and TIP were less than or equal to the motor vehicle emissions 
budget level defined by the SIP as being consistent with clean air.
    The first 8-hour ozone SIP could be a control strategy SIP required 
by the Clean Air Act (e.g., rate-of-progress SIP or attainment 
demonstration) or a maintenance plan. The first SIP could also be 
submitted earlier and demonstrate a significant level of emission 
reductions from the current level of emissions. For example, an area 
could submit an early 8-hour ozone SIP that demonstrates a specific 
percentage of emission reductions (e.g., 5-10%) in the year 2007, from 
2002 baseline year emissions. An early 8-hour SIP would include 
emissions inventories for all emissions sources for the entire 8-hour 
nonattainment area and would meet applicable requirements for 
reasonable further progress SIPs. EPA has discussed such an option in 
the context of its 8-hour ozone implementation rule (June 2, 2003, 68 
FR 32822) and the 1997 final conformity rule (August 15, 1997, 62 FR 
43798-43799).
    Whatever the case, the interim emissions test(s) would no longer 
apply for conformity purposes for either NOX or VOCs once an 
8-hour ozone SIP is submitted and EPA has found adequate or approved 
its budget(s) for that ozone precursor. Section 93.118 of the current 
rule describes the budget test; references in Sec.  93.118(a) are being 
updated in this proposal to be consistent with proposed changes in 
Sec.  93.109.
    EPA encourages nonattainment areas to develop their 8-hour ozone 
SIPs in consultation with state and local air quality and 
transportation agencies to facilitate future conformity determinations. 
EPA Regions are available to assist on an ``as needed'' basis, 
including consultation on the development of early 8-hour ozone SIPs.
2. Conformity Before 8-Hour Ozone SIP Budgets Are Adequate or Approved
    The following paragraphs outline the options for doing conformity 
before adequate or approved 8-hour ozone SIP budgets are established in 
8-hour ozone areas covered by this section of the proposal.
    Marginal and below classifications and subpart 1 areas. 8-hour 
ozone areas that are not of moderate and above classifications include: 
8-hour ozone areas of marginal and below classifications and 8-hour 
ozone areas designated nonattainment under Clean Air Act subpart 1.
    EPA proposes that these 8-hour ozone areas must pass one of the 
following tests for conformity determinations that occur before 
adequate or approved 8-hour ozone SIP budgets are in place:
    [sbull] The build-no-greater-than-no-build test, or
    [sbull] The no-greater-than-2002 emissions test.

In other words, this proposal would give these 8-hour ozone areas a 
choice between two interim emissions tests, rather than provide only 
one test or require that both tests be completed. Conformity would be 
demonstrated if the transportation system emissions reflecting a 
proposed transportation plan or TIP were less than or equal to either 
the emissions from the existing transportation system (no-build) or the 
level of motor vehicle emissions in 2002.
    A discussion of the proposed changes to the interim emissions tests 
can be found in Section IV. of this proposal. See the proposed 
regulatory text in Sec.  93.119(b)(2). See EPA's June 2, 2003, proposed 
implementation rule for the 8-hour ozone standards (68 FR 32811-32816) 
for more information on the proposal to designate some 8-hour ozone 
areas under Clean Air Act subpart 1.
    Moderate and above classifications. As described in Section IV.D., 
EPA proposes three options for regional emissions analyses in moderate 
and above 8-hour ozone areas that do not have adequate or approved 1-
hour ozone SIPs. The options are:
    (1) Complete both the build-less-than-no-build and less-than-
baseline year tests;
    (2) complete either the build-less-than-no-build or less-than-
baseline year test; or
    (3) require that only one of these tests be met and eliminate the 
remaining test as an option altogether.

The proposed regulatory text in Sec.  93.119(b)(1) reflects the first 
option, although EPA could finalize any one of the three proposed 
options.
3. Options for 8-Hour Ozone Areas That Qualify for EPA's Clean Data 
Policy
    The proposal would also extend the current conformity rule's 
flexibility for certain 1-hour ozone ``clean data areas'' to 8-hour 
ozone areas that are required to meet certain SIP requirements (e.g., 
moderate and above ozone areas). Today's conformity proposal is also 
consistent with the clean data option in EPA's proposed 8-hour ozone 
implementation rule (June 2, 2003, 68 FR 32835).
    As background, EPA issued a policy memorandum on May 10, 1995 that 
addressed SIP requirements in a small number of moderate and above 
ozone areas (entitled ``Reasonable Further Progress, Attainment 
Demonstrations, and Related Requirements for Ozone Nonattainment Areas 
Meeting the Ozone National Ambient Air Quality Standard''). Under the 
May 1995 policy, EPA could declare through rulemaking that a moderate 
or above 1-hour ozone area was a ``clean data area,'' if an area had 
sufficient monitoring data showing attainment of the 1-hour ozone 
standard. A clean data area is not required to submit any outstanding 
reasonable further progress or attainment SIPs, since the area is 
already attaining the standard. Section 93.109(c)(5) of the existing 
conformity rule allows clean data areas for the 1-hour ozone standard 
to request that a budget based on the level of motor vehicle emissions 
in the most recent year of clean data be established through EPA's 
rulemaking that determines an area to be a clean data area.
    Similarly, today's proposal would allow 8-hour ozone areas that 
have clean data and are required to submit

[[Page 62701]]

control strategy SIPs to use one of the following three tests to 
complete conformity:
    [sbull] The interim emissions tests, as described above;
    [sbull] The budget test using the adequate or approved motor 
vehicle emissions budgets in a submitted 8-hour ozone SIP; or
    [sbull] The budget test using the motor vehicle emissions level in 
the most recent year of clean data as budgets, if the state or local 
air quality agency requests that budgets be established by EPA's clean 
data rulemaking for the 8-hour ozone standard.

The proposed regulatory text for these options is in Sec.  
93.109(d)(5).
    This part of the proposal would be provided to moderate and above 
ozone areas with three years of clean data for the 8-hour ozone 
standard that have not submitted a maintenance plan and that EPA has 
determined are not subject to the Clean Air Act's reasonable further 
progress and attainment demonstration requirements. In addition, some 
subpart 1 areas would also be covered by this conformity proposal if 
such areas are required to submit control strategy SIPs, as proposed in 
the June 2003 ozone implementation rule. Please note that EPA's 
proposed clean data SIP policy and therefore today's conformity 
proposal might not be used by any area for the first conformity 
determination, since newly designated nonattainment areas may not yet 
have three years of clean data for the 8-hour ozone standard.
4. General Implementation of Regional Tests
    The proposal also retains the existing rule's general requirement 
that regional emissions analyses for ozone areas must address ozone 
precursors, which are nitrogen oxides (NOX) and volatile 
organic compounds (VOCs) (40 CFR 93.102(b)(2)(i)). All proposed interim 
emissions test options would be required to address both VOC and 
NOX precursors, unless EPA determines that additional 
reductions of NOX would not contribute to attainment for the 
8-hour ozone standard and issues a NOX waiver under Clean 
Air Action section 182(f). This is consistent with the current 
conformity rule, although the proposal moves these provisions to Sec.  
93.119(f) due to reorganization of Sec.  93.119. Finally, the proposal 
retains the current rule's provision that the interim emissions test(s) 
be completed for NOX if a reasonable further progress SIP is 
submitted with only a budget for VOCs (e.g., a 15% SIP). See Sec.  
93.109(d)(3) for this proposed regulatory text.
    The consultation process should be used to determine the models and 
assumptions for completing either the interim emissions tests or the 
budget test, as required by Sec.  93.105(c)(1)(i) of the current rule. 
See the proposed regulatory text in Sec.  93.109(d) for a general 
overview of when the budget test and interim emissions tests would 
apply in 8-hour ozone nonattainment areas without 1-hour ozone SIP 
budgets.

B. Why Are We Proposing These Options?

    EPA has been told by some stakeholders that it is reasonable and 
credible to provide 8-hour ozone areas with the same flexibility that 
applies under the 1-hour ozone standard. To that end, EPA has proposed 
that 8-hour ozone areas with fewer SIP requirements (e.g., marginal and 
subpart 1 areas) continue to have the choice offered by the current 
rule between the baseline year and build/no-build tests. EPA gave this 
choice to 1-hour ozone areas as described in the preamble to a previous 
proposal (July 9, 1996, 61 FR 36116-36117). EPA continues to believe 
that allowing these areas a choice of conformity tests during the time 
period before adequate or approved 8-hour ozone SIP budgets are in 
place is environmentally protective and meets the statutory 
requirements.
    As noted above, we are also considering three options for moderate 
and above ozone areas to ensure that every flexibility is provided to 
new 8-hour ozone areas while achieving environmental benefits. Please 
see EPA's rationale for these proposed options in Section IV.D.2.
    EPA is also responding to stakeholder requests that the rule 
continue to provide more choices to areas that would qualify for EPA's 
proposed 8-hour ozone clean data policy. If the proposed clean data 
policy is included in the final 8-hour ozone implementation rule, EPA 
proposes to also include the proposed conformity options for such areas 
in the final conformity rule for the new standards. See EPA's previous 
discussion and rationale for the clean data options from the preamble 
to the 1996 proposal and 1997 final rules (July 9, 1996, 61 FR 36116; 
and August 15, 1997, 62 FR 43784-43785, respectively).

VI. Regional Conformity Tests in 8-Hour Ozone Areas That Have 1-Hour 
Ozone SIPs

A. What Are We Proposing?

    EPA is proposing several options for completing regional emissions 
analyses in 8-hour ozone areas that have an existing 1-hour ozone SIP 
that covers either some or all of the 8-hour ozone nonattainment area.
1. Conformity After 8-Hour Ozone SIP Budgets Are Adequate or Approved
    Once a SIP for the 8-hour ozone standard is submitted with 
budget(s) that EPA has found adequate or approved, the budget test 
would be used to complete the regional emissions analysis. The first 8-
hour ozone SIP could be a control strategy SIP required by the Clean 
Air Act (e.g., rate-of-progress SIP or attainment demonstration). The 
first SIP could also be submitted earlier and demonstrate a significant 
level of emission reductions from the current level of emissions, as 
described in Section V.A.1. Interim emissions tests and/or any existing 
1-hour ozone SIP budgets (as described below) would no longer be used 
for conformity for either NOX or VOCs once an adequate or 
approved 8-hour ozone SIP is established for such a precursor. State, 
local, and Federal air quality and transportation agencies should 
consult on the development of 8-hour ozone SIPs as appropriate.
2. Conformity Before 8-Hour Ozone SIP Budgets Are Adequate or Approved
    The following paragraphs outline the options for determining 
conformity before adequate or approved 8-hour ozone SIP budgets are in 
place in 8-hour ozone areas with existing 1-hour ozone SIP budgets. EPA 
is proposing that these 8-hour ozone areas be able to select one test 
option from among a menu of test options for completing the regional 
emissions analysis requirement, rather than be required to complete a 
specific test(s).
    Summary of Options: The following table summarizes the menu of 
proposed options, based on the placement of 1-hour and 8-hour ozone 
nonattainment boundaries:

----------------------------------------------------------------------------------------------------------------
           Boundary scenario                   Menu of options                 Proposed regulatory text
----------------------------------------------------------------------------------------------------------------
8-hour area = 1-hour area..............  Interim emissions test(s)   Sec.   93.109(e)(2)(i) OR
                                          OR.
                                         Budget test using 1-hour    Sec.   93.109(e)(2)(ii)(A).
                                          budget(s).
8-hour area < 1-hour area..............  Interim emissions test(s)   Sec.   93.109(e)(2)(i) OR
                                          OR.

[[Page 62702]]

 
                                         Budget test for 1-hour      Sec.   93.109(e)(2)(ii)(B) OR
                                          area (with 1-hour
                                          budget(s)) OR.
                                         Budget test for 8-hour      Sec.   93.109(e)(2)(ii)(B).
                                          area (with applicable
                                          subset of 1-hour
                                          budget(s)).
8-hour area  1-hour area....  Interim emissions test(s)   Sec.   93.109(e)(2)(i) OR
                                          OR.
                                         Budget test (with 1-hour    Sec.   93.109(e)(2)(ii)(C).
                                          budget(s)) PLUS Interim
                                          emissions test(s) (for
                                          remainder of 8-hour area).
Portions of 8-hour and 1-hour areas      Interim emissions test(s)   Sec.   93.109(e)(2)(i) OR
 overlap.                                 OR.
                                         Budget test (with           Sec.   93.109(e)(2)(ii)(C)
                                          applicable subset of
                                          areas 1-hour budget(s))
                                          PLUS Interim emissions
                                          test(s) (for remainder of
                                          8-hour area).
----------------------------------------------------------------------------------------------------------------

    EPA has posted pictures of hypothetical boundary scenarios for 
further clarification on the transportation conformity website listed 
in Section I.B.2.
    Please note that the proposed options are for completing conformity 
under the 8-hour ozone standard. EPA is proposing that the budget test 
with existing 1-hour ozone SIP budgets be used as a test option (or 
proxy) for the 8-hour ozone standard, rather than the 1-hour ozone 
standard. Conformity for the 1-hour and 8-hour ozone standards would 
not apply at the same time, as proposed in EPA's 8-hour ozone 
implementation rule (June 2, 2003, 68 FR 32819). In addition, for the 
reasons explained below, EPA is not proposing that 8-hour ozone areas 
must use their 1-hour ozone budgets if such budgets exist; we are 
proposing only that the budget test using the 1-hour ozone budgets 
would be an option as appropriate in addition to the interim emissions 
test(s).
    The following paragraphs describe the above table in further detail 
as well as sub-options that are being proposed for some boundary 
scenarios. For all scenarios, once an area selects a particular 
test(s), EPA proposes that it must be used consistently for all 
regional analysis years.
    Scenario where 8-hour and 1-hour ozone boundaries are exactly the 
same. In this case, the 8-hour and 1-hour ozone boundaries cover 
exactly the same geographic area. EPA proposes to require such areas 
meet one of the following:
    [sbull] The interim emissions tests, depending upon an area's 
classification or designation; or
    [sbull] The budget test using existing adequate or approved 1-hour 
ozone SIP budgets.

See Section V. for further description of which interim emissions 
test(s) would apply in a given 8-hour ozone area.
    Scenario where the 8-hour ozone boundary is smaller than and within 
the 1-hour ozone boundary. In this case, the 8-hour nonattainment area 
is smaller than and completely encompassed by the 1-hour nonattainment 
boundary. Again, EPA proposes to require such areas meet one of the 
following:
    [sbull] The interim emissions tests, depending upon an area's 
classification or designation;
    [sbull] The budget test using the subset or portion of existing 
adequate or approved 1-hour ozone SIP budgets that overlaps with the 8-
hour nonattainment area; or
    [sbull] The budget test using the existing adequate or approved 1-
hour ozone SIP budgets for the entire 1-hour nonattainment area (any 
additional reductions must come from the 8-hour nonattainment area, as 
described below).
    EPA also requests comment on when it would be feasible and 
appropriate to allow an area to use a subset or portion of a 1-hour 
ozone SIP budget for 8-hour ozone conformity. Such a test option 
requires an area to subtract from the 1-hour ozone budget and 
conformity analysis those emissions that are not produced in the 8-hour 
ozone area. For example, this would be straightforward if the on-road 
mobile inventory for the 1-hour ozone SIP budget is calculated by 
county, and the portion to be subtracted is a specific county that is 
not part of the 8-hour ozone area. However, this may not be appropriate 
in the case where the SIP does not clearly specify the amount of 
emissions in the portion of the 1-hour ozone area not covered by the 8-
hour ozone area. The consultation process would be used to determine 
when using a portion of a 1-hour ozone SIP budget is appropriate, and 
if so, how deriving such a portion would be accomplished. EPA requests 
other examples for when using a portion of a 1-hour ozone SIP budget 
would be feasible and appropriate.
    In addition, EPA notes that adjusting the 1-hour ozone budgets for 
purposes of conducting 8-hour ozone conformity analyses would be 
legally appropriate since any 1-hour ozone SIP demonstrations and 
budgets would only be used as a proxy for the 8-hour ozone standard and 
would themselves no longer be for an applicable standard (i.e., since 
the 1-hour ozone standard would be revoked under EPA's proposed 8-hour 
ozone implementation rule).
    A conformity determination based on the entire 1-hour ozone budget 
would include a comparison between the on-road regional emissions 
produced in the entire 1-hour ozone area and existing 1-hour ozone 
budgets. However, if additional reductions are required to meet 
conformity, EPA proposes that such reductions could only be obtained 
within the 8-hour ozone nonattainment area, since the conformity 
determination would be for the 8-hour ozone standard.
    Scenarios where the 8-hour ozone boundary is larger than or 
overlaps with a portion of the 1-hour ozone boundary. This part of the 
proposal covers the third and fourth scenarios listed in the above 
table in this section. The third scenario would result if an entire 1-
hour ozone nonattainment area is within a larger 8-hour ozone 
nonattainment area. The fourth scenario would result if 1-hour and 8-
hour ozone nonattainment boundaries partially overlap. In both types of 
8-hour ozone areas, the 1-hour ozone budgets would not cover the entire 
8-hour nonattainment area. Therefore, existing 1-hour ozone budgets 
cannot be the sole test of conformity under the 8-hour ozone standard 
in these scenarios, since a conformity determination must include a 
regional emissions analysis that covers the entire 8-hour ozone 
nonattainment area.
    EPA is proposing that areas in these scenarios meet one of the 
following:
    [sbull] The applicable interim emissions tests for the entire 8-
hour ozone area; or
    [sbull] The budget test based on the 1-hour ozone budget(s) for the 
1-hour ozone area or relevant subset or portion of the 1-hour ozone 
area, plus the interim emissions test(s) for the remaining portion of 
the 8-hour ozone nonattainment area.
    As stated above, once an area selects a particular test(s), EPA 
proposes that it must be used consistently for all regional analysis 
years.

    For example, a marginal or below 8-hour ozone area that is larger 
than the

[[Page 62703]]

1-hour ozone area (third scenario) could choose to complete the budget 
test for the 1-hour ozone nonattainment area and the no-greater-than-
2002 test for the remaining portion of the 8-hour ozone area for the 
attainment year, an intermediate year, and the last year of the 
transportation plan. EPA is not proposing to require such an area to 
complete the interim emissions test for the entire 8-hour ozone 
nonattainment area in all cases, in addition to the budget test with 
the 1-hour ozone SIP. EPA acknowledges that there may be cases where it 
is difficult to separately model the remaining portion of the 8-hour 
ozone area, e.g., in an area where the remaining 8-hour ozone area is a 
ring of counties around the 1-hour ozone area. However, in this case, 
an area could always choose to complete only the interim emissions 
test(s) for the entire 8-hour ozone area, rather than the budget test 
with 1-hour ozone SIP budgets for the 1-hour ozone area.
    For areas covered by the third boundary scenario in the above table 
where the 8-hour ozone area is larger than the 1-hour ozone area, the 
budget test would be completed for the entire 1-hour ozone area, as is 
done for conformity determinations for the 1-hour ozone standard. For 
areas covered by the fourth scenario where 8-hour and 1-hour ozone 
areas overlap, the budget test would only be done for the portion of 
the 1-hour ozone area and budgets that overlap with the 8-hour ozone 
area. EPA acknowledges that the budget test with a portion of a 1-hour 
ozone budget may be difficult to implement in many areas, since it 
assumes that areas will be able to determine easily the amount of 
budget emissions that are in the relevant portion. EPA requests 
examples for when using a portion of a 1-hour ozone budget would be 
appropriate and how to calculate such a portion. The consultation 
process would be used to determine whether the budget test for the 
fourth scenario is appropriate and if so, how it should be implemented.
    Finally, EPA notes that the consultation process should be used to 
determine which analysis years should be selected for regional 
emissions analyses where the budget test and interim emissions tests 
are used. Sections 93.118(d) and 93.119(e) of the current conformity 
rule require similar analysis years for modeling in the last year of 
the transportation plan and for any intermediate years for both budget 
and interim emissions tests. However, the analysis years for the short-
term may be different for the budget test and interim emissions tests 
in some cases. For example, Sec.  93.118 requires modeling for the 
budget test to be completed for the attainment year if it is within the 
timeframe of the transportation plan; Sec.  93.119 requires the first 
analysis year for the interim emissions tests to be within the first 
five years of the transportation plan. The consultation process can be 
used to pick analysis years that would satisfy both the budget and 
interim emissions test requirements for areas using both tests prior to 
adequate or approved 8-hour ozone SIP budgets being established.
3. Options for 8-hour Ozone Areas That Qualify for EPA's Clean Data 
Policy
    As described in Section V.A.3., today's conformity proposal would 
also extend the current rule's flexibility for certain 1-hour ozone 
areas to 8-hour ozone areas that are covered by EPA's June 2, 2003 
proposal (68 FR 32835). The June 2003 proposal extends the existing 1-
hour ozone clean data policy for the SIP process to future 8-hour ozone 
areas that are required to submit control strategy SIPs.
    Specifically, we are proposing to require such 8-hour ozone areas 
with adequate or approved 1-hour ozone SIP budgets to meet one of the 
following four options to complete conformity:
    [sbull] The interim emissions tests, as described in Section V.;
    [sbull] The budget test using the adequate motor vehicle emissions 
budgets in a submitted control strategy SIP for the 8-hour ozone 
standard;
    [sbull] The budget and/or interim emissions tests using existing 1-
hour ozone SIP budgets and/or applicable interim emissions tests, as 
described in A.3. of this section for different scenarios of 1-hour and 
8-hour ozone nonattainment boundaries; or
    [sbull] The budget test using the motor vehicle emissions level in 
the most recent year of clean data as budgets, if such budgets are 
established by the EPA rulemaking that determines an area to have clean 
data for the 8-hour ozone standard.

See the proposed regulatory text for these options in Sec.  
93.109(e)(4).
4. General Implementation of Regional Tests
    The proposal also retains the existing rule's general requirements 
that regional emissions analyses for ozone areas must address 
NOX and VOC precursors (40 CFR 93.102(b)(2)(i)). All 
proposed interim emissions test options would be required to address 
both precursors, unless EPA determines that additional reductions of 
NOX would not contribute to attainment for the 8-hour ozone 
standard and issues a NOX waiver under Clean Air Action 
section 182(f). This is consistent with the current conformity rule, 
although the proposal moves these provisions to Sec.  93.119(f) due to 
reorganization of Sec.  93.119. Finally, the proposal retains the 
current rule's provision that the interim emissions test(s) be 
completed for NOX if a reasonable further progress SIP is 
submitted with only a budget for VOCs (e.g., a 15% SIP). See Sec.  
93.109(e)(3) for this proposed regulatory text.
    The consultation process should be used to determine the models and 
assumptions for completing the interim emissions tests and/or the 
budget test, as required by Sec.  93.105(c)(1)(i) of the current rule. 
The consultation process can also be used to select the conformity 
test(s) before 8-hour ozone SIPs are submitted. See the proposed 
regulatory text in Sec.  93.109(e) for a general overview of when the 
budget test and interim emissions tests apply in 8-hour ozone 
nonattainment areas with 1-hour ozone SIP budgets.

B. Why Are We Proposing These Options?

    EPA has received stakeholder input asking EPA to provide 8-hour 
ozone areas with conformity flexibility in the time period before 8-
hour ozone SIPs are established. In response, EPA is proposing a menu 
of options for 8-hour ozone areas that have existing 1-hour ozone SIP 
budgets, rather than requiring only one conformity test be used. 
Allowing areas to choose between the interim emissions tests and/or the 
budget test based on 1-hour ozone SIPs would accommodate the many 
different boundary scenarios described in VI.A.2.
    EPA has previously found that the interim emissions tests are 
sufficient for meeting the Clean Air Act requirements for a given 
standard before a SIP with adequate budgets is in place for that 
standard. As discussed in Sections IV. and V. of this proposal, EPA 
believes that Clean Air Act sections 176(c)(1) and (c)(3)(A)(iii) can 
be met through only one or a combination of interim emissions tests, 
depending upon an area's classification.
    Our proposal to allow areas to use the 1-hour ozone budgets before 
8-hour ozone budgets are available does not mean that areas would be 
determining conformity for the 1-hour ozone standard. As articulated in 
the proposed 8-hour ozone implementation rule, EPA is proposing that 
conformity for only one ozone standard apply at a time (June 2, 2003, 
68 FR 32823-32824).
    We are proposing to offer the budget test as a choice because we 
think that many 1-hour ozone budgets provide as good an analytical test 
as the other tests that exist or are proposed for use before

[[Page 62704]]

8-hour ozone budgets are available: the build/no-build and baseline 
year tests. In general, EPA believes the 1-hour ozone budgets may be an 
appropriate test like the build/no-build test, because the 1-hour ozone 
VOC and NOX budgets that an area has represent a reduction 
in emissions that is consistent with the applicable SIP for that 
standard. Although the 8-hour ozone standard is more stringent than the 
1-hour ozone standard, many 1-hour ozone budgets have in fact served to 
reduce emissions over time. For example, the Clean Air Act requires 
that transportation plans and TIPs reduce emissions in the higher 
classifications of ozone and CO areas before a SIP for a given 
pollutant and standard is developed. We believe that the budget test 
using 1-hour ozone budgets may meet this requirement at least as well 
as the build/no-build test.
    EPA also believes that the 1-hour ozone budgets may be comparable 
to the baseline year test for conformity under the 8-hour ozone 
standard. The baseline year test could actually be thought of as a type 
of budget test before 8-hour ozone budgets are established: emissions 
in the year 2002 become the ceiling on emissions, a defacto budget. The 
budgets in 1-hour ozone SIPs are at least as good as the 2002 baseline 
year test if areas are meeting them when they are designated for the 8-
hour ozone standard. In the case where 2002 emissions are higher than 
established 1-hour ozone budgets, the budget test would actually be a 
more conservative test. However, in the case where 2002 emissions are 
lower than the 1-hour ozone budgets, the budgets should still be a 
valid test since they provide for attainment of the 1-hour ozone 
standard. In other words, consistency with the 1-hour budgets would 
have resulted in a certain level of emissions at the time areas were 
designated for the 8-hour ozone standard. An area's designation as a 
nonattainment area for the 8-hour ozone standard would be based on its 
air quality monitoring data for the years 2001-2003. Therefore, EPA 
does not anticipate that many areas will have 2002 emissions 
significantly lower than 1-hour budgets since areas would not have 
likely put control measures in place by 2002 that would result in lower 
emissions for that year. We believe that consistency with the 1-hour 
ozone budgets would assure an emissions level that is in line with the 
baseline year test, since the baseline year is 2002.
    However, EPA does not believe that 8-hour ozone areas that have 1-
hour ozone budgets must use these budgets for conformity prior to the 
development of 8-hour ozone budgets. Although an area could conclude 
through the consultation process that use of a 1-hour ozone budget 
would be appropriate, there may be many cases where the 1-hour ozone 
budget would not provide the best test for conformity to the 8-hour 
ozone standard. For instance, 1-hour ozone budgets could be for a year 
different than the year for which 8-hour ozone conformity is being 
demonstrated. For example, 1-hour budgets could be from a rate-of-
progress SIP (e.g., a 15% plan) for a past milestone year, such as 
1996, that is no longer relevant to projected emissions in the post-
2002 period for the 8-hour ozone standard. In contrast, an area may 
only have a 1-hour ozone maintenance plan with budgets for a year 
beyond the 8-hour ozone attainment year. The planning assumptions (such 
as VMT, vehicle fleet characteristics, speeds) underlying the 1-hour 
budget may also be significantly out-of-date.
    Thus, although it is appropriate to offer areas the opportunity to 
use 1-hour ozone budgets, EPA believes that they should not be mandated 
and that the consultation process should be used to select the most 
appropriate test for a particular area prior to the development of 
adequate or approved 8-hour ozone SIP budgets. EPA requests comment on 
this proposal to allow areas to use applicable 1-hour ozone budgets to 
demonstrate conformity prior to the development of 8-hour ozone 
budgets, and to use the consultation process to determine whether such 
budgets should be used.
    Finally, today's proposal responds to stakeholder requests that the 
rule continue to offer more choices to new ozone areas that would 
qualify for EPA's proposed 8-hour ozone clean data policy. If the 
proposed 8-hour ozone clean data policy is included in the final 8-hour 
ozone implementation rule, EPA would also include the proposed 
conformity options for such areas in the final conformity rule for the 
new standards. See EPA's previous discussion and rationale for the 
clean data options in the preamble to the 1996 proposal and 1997 final 
rules (July 9, 1996, 61 FR 36116, and August 15, 1997, 62 FR 43785, 
respectively).

VII. Regional Conformity Tests in PM2.5 Areas

A. What Are We Proposing?

    EPA proposes that the budget test would be used to complete a 
regional emissions analysis once a PM2.5 SIP is submitted 
with budget(s) that EPA has found adequate or approved. Although the 
first PM2.5 SIP may be an attainment demonstration, 
PM2.5 nonattainment areas ``are free to establish, through 
the SIP process, a motor vehicle emissions budget [or budgets] that 
addresses the new NAAQS in advance of a complete SIP attainment 
demonstration. That is, a state could submit a motor vehicle emissions 
budget that does not demonstrate attainment but is consistent with 
projections and commitments to control measures and achieves some 
progress towards attainment.'' (August 15, 1997, 62 FR 43798-43799). 
Such a SIP would include inventories for all emissions sources. EPA 
encourages nonattainment areas to develop their PM2.5 SIPs 
in consultation with Federal, state, and local air quality and 
transportation agencies as appropriate.
    EPA is proposing that PM 2.5 nonattainment areas meet 
one of the following interim emissions tests for conformity 
determinations conducted before adequate or approved PM2.5 
SIP budgets are established:
    [sbull] The build-no-greater-than-no-build test, or
    [sbull] The no-greater-than-2002 emissions test.

    This proposal would allow PM2.5 nonattainment areas to 
choose between the two interim emissions tests, rather than require 
that only one test or both tests be completed. Conformity would be 
demonstrated if the transportation system emissions reflecting the 
proposed plan or TIP (build) were less than or equal to either the 
emissions from the existing transportation system (no-build) or the 
level of motor vehicle emissions in 2002. A discussion of the proposed 
changes to the interim emissions tests can be found in Section IV.
    The proposal would require that regional emissions analyses always 
be completed for directly emitted PM2.5 from motor vehicle 
tailpipe, brake wear, and tire wear emissions. Once a SIP is submitted, 
the budget test would also be completed for any PM2.5 
precursor for which an adequate or approved budget is established. 
Prior to adequate or approved SIP budgets, an interim emissions test 
would be completed for each applicable PM2.5 precursor, as 
described in Section VIII. Sections IX. and X. describe proposed 
options for when regional emissions analyses would include direct 
PM2.5 emissions from re-entrained road dust and 
construction-related dust.
    The consultation process should be used to determine the models and 
assumptions for completing any regional emissions analysis, as required 
by Sec.  93.105(c)(1)(i). See the proposed regulatory text in Sec.  
93.109(i) for a general overview of when the budget test and interim 
emissions tests apply in

[[Page 62705]]

PM2.5 areas, and Sec.  93.119(e) for a description of the 
interim emissions tests for PM2.5 nonattainment areas.

B. Why Are We Proposing These Options?

    We believe that the proposal addresses the concerns of many 
stakeholders by providing flexibility before adequate or approved 
PM2.5 SIP budgets are established. While many 
PM2.5 areas will have prior conformity experience with 
different pollutants, others will be doing conformity for the first 
time. In either case, the conformity process provides an important 
opportunity to begin addressing transportation-related PM2.5 
emissions early to ensure that air quality is not worsened before SIPs 
are submitted. Proposing a choice of interim emissions tests before 
SIPs are submitted addresses the desire for flexibility and 
environmental protection.
    EPA has previously determined that only ozone and CO areas of 
higher classifications are required to satisfy both statutory 
requirements that transportation planning activities not cause or 
contribute to violations of the standards (Clean Air Act section 
176(c)(1)(B)) and that such activities contribute to annual emissions 
reductions (Clean Air Act section 176(c)(3)(A)(iii)) (January 11, 1993 
proposed rule, 58 FR 3782-3783). EPA continues to believe that Clean 
Air Act section 176(c)(3)(A)(iii) does not apply to any other areas, 
including PM2.5 areas; only Clean Air Act section 
176(c)(1)(B) applies to these areas.
    To that end, the current conformity rule already allows many areas 
to conform based on only one interim emissions test if transportation 
emissions are consistent with current air quality expectations, rather 
than having to complete two tests and contribute further reductions 
towards attainment. Today's proposal continues to apply this same test 
structure and rationale to PM2.5 areas.

VIII. Consideration of Direct PM2.5 and PM2.5 
Precursors in Regional Emissions Analyses

A. What Are We Proposing?

    We are proposing to require that all regional emissions analyses in 
PM2.5 nonattainment and maintenance areas consider all 
sources of directly emitted PM2.5 motor vehicle emissions 
from the tailpipe, brake wear, and tire wear. Proposed regulatory text 
can be found in Sec.  93.102(b)(1). See Sections IX. and X. for the 
proposed options for including direct PM2.5 from re-
entrained road dust and construction-related dust in conformity 
analyses.
    This proposal would also add potential transportation-related 
PM2.5 precursors--NOX, VOCs, sulfur oxides 
(SOX ), and ammonia (NH3)-for consideration in 
the conformity process. Once a PM2.5 SIP is submitted, a 
regional emissions analysis would be required for a given precursor if 
the SIP establishes an adequate or approved budget for that particular 
precursor.
    The following two options address how the various PM2.5 
precursors would be considered in conformity determinations conducted 
before adequate or approved PM2.5 SIP budgets are 
established, for the reasons explained below. EPA is proposing 
regulatory text in Sec. Sec.  93.102(b)(2) and 93.119(f) for both of 
these options. We are providing the regulatory text for both options to 
maximize the public's opportunity to provide meaningful comments.
    The first proposed option would require regional emissions analyses 
for NOX and VOC precursors in all areas, unless the State 
air agency or the EPA Regional Administrator makes a finding that one 
or both of these specific precursors are not a significant contributor 
to the PM2.5 air quality problem in a given area. Regional 
emissions analyses would not be required for SOX and 
NH3 before an adequate or approved SIP budget for such 
precursors is established, unless the State or EPA makes a finding that 
on-road emissions of one or both of these precursors is a significant 
contributor. Under the first option, the MPO and DOT would document in 
their conformity determinations when regional emissions analyses are 
not being conducted when EPA or the State has determined NOX 
or VOCs to be insignificant.\3\
---------------------------------------------------------------------------

    \3\ The public would be notified of when NOX or VOC 
is considered insignificant through the documentation in a 
conformity determination under the first option.
---------------------------------------------------------------------------

    EPA's second option would only require regional emissions analyses 
for one or more PM2.5 precursors (i.e., NOX, VOC, 
SOX and NH3) before adequate or approved 
PM2.5 SIPs have been established if the State or EPA makes a 
finding that one or more of these precursors are significant 
contributors to the PM2.5 air quality problem in a given 
area.
    A State air agency or EPA finding of significance or insignificance 
(a ``significance finding'') would be based on criteria similar to the 
general criteria currently used by EPA to evaluate SIPs that claim on-
road emissions are insignificant for a given pollutant or precursor. 
EPA's existing policy for insignificance serves as the basis for 
today's proposal, as described in Section XIV.B. of this notice. The 
following criteria should be considered in making significance findings 
for PM2.5 precursors under either proposed option: the 
contribution of on-road emissions of the precursor to the total 2002 
baseline SIP inventory; the current state of air quality for the area; 
the results of speciation monitoring for the area; the likelihood of 
future motor vehicle control measures for a given precursor; and 
projections of future on-road emissions of the precursor. The State air 
agency or EPA Regional Administrator would determine significance or 
insignificance of motor vehicle emissions in a given area on a case-by-
case basis.
    Under either option, a significance finding should be made only 
after discussions with the interagency consultation group for the 
PM2.5 nonattainment area. These discussions should include a 
review of the available data being considered to support the 
significance finding. Interagency consultation also ensures that all of 
the relevant agencies are aware that such a finding is being 
considered. It is important to provide transportation agencies with 
adequate notice of which, if any, precursors they may need to address 
in conformity analyses. A significance finding would be made through a 
letter to the relevant State and local air quality and transportation 
agencies, MPO(s), DOT and EPA (in the case of a State air agency 
finding).
    EPA notes that any significance finding made prior to the SIP 
should not be viewed as the ultimate determination of the significance 
of precursor emissions in a given area. State and local agencies may 
find through the SIP development process that emissions of one or more 
precursors are significant, even if a precursor had previously been 
considered insignificant. In such a case, the PM2.5 SIP 
would establish motor vehicle emissions budgets and significant 
precursors would be included in subsequent conformity analyses.
    To calculate emission factors for direct PM2.5 from 
motor vehicles and PM2.5 precursors areas in all states 
except California would use the latest EPA-approved motor vehicle 
emissions factor model (currently MOBILE6). PM2.5 
nonattainment and maintenance areas in California should use EMFAC2002 
or a more recently EPA-approved model. It should be noted that 
EMFAC2002 currently does not calculate emissions factors for 
NH3.

[[Page 62706]]

However, EPA understands that California is working on a revision to 
EMFAC that should enable the model to calculate emissions factors for 
NH3. A schedule for completing the necessary revisions has 
not been established. As a practical matter, conformity for 
NH3 would not be required in California until there is an 
acceptable method for estimating such emissions, since a method would 
be needed to estimate current or future NH3 emissions for 
either a significance finding or SIP motor vehicle emissions budget.
    Including any precursors in regional emissions analyses prior to 
the submission of a SIP should not result in any additional 
transportation or emissions modeling work since the nonattainment areas 
will already be estimating vehicle miles traveled (VMT) from 
transportation activities for the direct PM2.5 regional 
emissions analysis. In addition, EPA's upcoming MOBILE6.2 and 
California's EMFAC2002 are designed to generate emissions factors for 
direct PM2.5 and PM2.5 precursors in the same 
modeling run. Therefore, if any area is already generating 
PM2.5 emissions factors, precursor estimates would be 
available without any additional effort, with the possible exception of 
NH3 estimates in California, as indicated above.

B. Why Are We Proposing These Options?

    Section 176(c)(1)(B) of the Clean Air Act requires that federal 
funding and approval be given only to transportation activities that 
are consistent with state and local air quality goals. To fulfill this 
requirement with respect to PM2.5, EPA is proposing that 
transportation conformity determinations consider PM2.5 and 
its precursors if they are significant contributors to an area's 
PM2.5 air quality problem.
    EPA anticipates that in most nonattainment and maintenance areas 
direct PM2.5 emissions would be an important contributor to 
the PM2.5 air quality problem, and therefore, we are 
proposing that direct PM2.5 emissions from motor vehicles be 
included in all conformity analyses. In addition, EPA's proposal to 
require conformity to all relevant budgets established in the 
PM2.5 SIP is consistent with the Clean Air Act in that 
transportation activities must conform to the air quality goals 
established and estimates of future emissions in the SIP for a given 
area.
    EPA has proposed NOX, VOCs, SOX, and NH3 as 
potential transportation-related PM2.5 precursors since all 
of these precursors are emitted from on-road motor vehicles. Based on 
data collected from monitoring sites in the national speciation trends 
network,\4\ secondary particles from precursors commonly account for 
over half of the total fine particle mass from all emissions sources 
measured at these sites. Therefore, we expect that areas may need to 
address on-road emissions of relevant precursors (i.e., NOX, 
VOC, SOX and NH3) in their SIPs and in 
conformity.
---------------------------------------------------------------------------

    \4\ The speciation trends network consists of over 50 monitoring 
sites in urban areas and provides nationally consistent data on 
PM2.5 constituents including nitrates, elemental carbon, 
organic carbon and sulfates.
---------------------------------------------------------------------------

    EPA believes that the two proposed options would allow for the 
consideration of the four potential precursors in conformity prior to 
PM2.5 SIPs when such precursors are significant. However, 
they differ in terms of whether a NOX or VOC precursor is 
presumed to be significant and considered in conformity from the start, 
or whether a finding of significance is necessary before a precursor is 
addressed. The proposed options attempt to strike a balance between: 
(1) Expeditiously addressing transportation-related emissions that 
could exacerbate the PM2.5 air quality problem before a SIP 
is established, and (2) targeting conformity requirements in 
PM2.5 areas in an efficient and reasonable manner. As 
described above, the proposed options would only require SOX 
and NH3 analyses if either precursor was found to be 
significant before a PM2.5 SIP.
    For example, the first proposed option is more environmentally 
conservative by requiring that NOX and VOC conformity 
analyses be included in all areas initially. If EPA finds that in most 
areas motor vehicle emissions of these precursors are significant 
contributors to PM2.5 air quality problems, it may warrant 
the first option's more straightforward approach to meeting Clean Air 
Act requirements. In other words, areas would begin addressing 
NOX and VOC emissions upon designation under the first 
option, without having a separate state or EPA finding of significance. 
This option is similar to the current rule's requirement that ozone 
areas must address NOX and VOC precursors.
    On the other hand, the second proposed option is consistent with 
the current rule's approach for PM10 precursors, where NOX 
and VOC conformity analyses are only conducted prior to PM10 
SIPs if the State or EPA finds either precursor significant (40 CFR 
93.102(b)(2)(iii)). EPA finalized this approach in the November 24, 
1993 conformity rule because at that time secondary formation appeared 
to be less important for the PM10 NAAQS in general, although 
some PM10 areas have since established NOX and/or 
VOC SIP budgets.
    The second proposed option would account for regional variability 
and target conformity analyses where EPA or the state determine 
NOX and VOC precursors to be significant to an area's 
PM2.5 problem. Although we know that NOX and VOC 
precursors generally play a more important role in PM2.5 
formation, we continue to gather more specific information on the 
significance of these precursors in different parts of the country. One 
could argue that it may be more appropriate to focus scarce state and 
local efforts on NOX and VOC precursors only when they are 
determined to be significant, especially if adopting control measures 
early in conformity may prove not to be necessary in the 
PM2.5 SIPs.
    The following paragraphs present information on current speciated 
air quality data and on-road emissions of the precursors that 
contribute to the formation of secondary particles. The information is 
intended to illustrate what we know about PM2.5 precursor 
emissions and air quality. This type of information is relevant to 
deciding whether or not to initially require that a precursor be 
considered in conformity before a more thorough evaluation is conducted 
through the SIP development process. The emission inventory data used 
in the following discussion is for 372 potential nonattainment counties 
based on 1999-2001 ambient data.\5\ Summaries of the air quality and 
emissions inventory data discussed below are available in the docket 
for this rulemaking. More detailed air quality emission inventory data 
is available on the EPA Web site at http://www.emissionsonline.org/nei99v3/index.htm. The public is welcome to submit additional data on 
the importance of including PM2.5 precursors in conformity 
before SIPs are established.
---------------------------------------------------------------------------

    \5\ Through this data, we identified 129 counties that have 
violating monitors for PM2.5. EPA is currently reviewing 
2000-2002 ambient data which may affect the numbers discussed in 
today's proposal.
---------------------------------------------------------------------------

    NOX precursor emissions. On-road sources accounted for 
approximately 40% of total NOX emissions in 1999 in the 372 
potential nonattainment counties. Based on data collected from 
monitoring sites in the national speciation trends network, nitrates--
which result from reactions involving NOX--make up between 5 
and 40% of the total PM2.5 constructed mass. The areas with 
the highest percentages of nitrates are in California and parts of the

[[Page 62707]]

Midwest. The areas with lowest percentages tend to be in the southeast, 
where nitrates make up only 5 to 10% of the total PM2.5 
constructed mass.
    The 2003 NARSTO-PM report (``Particulate Matter Science for Policy 
Makers: A NARSTO Assessment,'' February 2003) states, ``Nitrates 
represent a major fraction of the PM2.5 mass measured in 
some locations, though the management of the nitrate fraction via 
NOX emission reductions needs to be addressed in combination 
with VOCs, NH3 and SO2. This must be done in 
consideration of the relationship between nitrate production and local 
or regional ozone formation.'' The report also states, ``Reductions of 
NOX, VOCs, and associated NH3 throughout the year 
in and around large urban areas may be important in the East as well as 
the West to bring down the nitrate contributions to the 24-hr and/or 
annual PM averages. While summer nitrate concentrations in eastern 
North America are low in comparison with other PM2.5 
components, higher winter nitrate concentrations occur in northern 
urban areas.'' The report goes on to indicate that the application of 
chemical transport models and comprehensive air quality monitoring will 
be useful in determining how best to address nitrates.
    A number of factors should be taken into account when considering 
the two options for addressing NOX as presented above. The 
first proposed option (which specifies that conformity demonstrations 
during the pre-SIP period must cover NOX unless a finding is 
made that NOX is not a significant contributor to the area's 
PM2.5 problem) is supported by the fact that on a national 
basis, NOX is clearly a significant contributor to the 
PM2.5 problem, that nitrates constitute some portion of the 
problem in each metropolitan area, and that on-road sources are 
significant contributors of NOX emissions in the potential 
nonattainment counties. In addition, assuming further sulfur dioxide 
reductions are required in order to attain the PM2.5 
standards, certain areas may see an increase in nitrate formation as 
sulfur dioxide emissions decline due to the reaction of ammonia with 
NOX, which in relative terms would be more ``available'' for 
such reactions. In order to minimize this ``NOX disbenefit'' 
situation, NOX emissions should be further reduced at the 
same time. These factors may argue that a more environmentally 
conservative approach is needed to meet the Clean Air Act conformity 
provisions, and that NOX should be considered in conformity 
analyses under the first proposed option unless the State or EPA 
determine otherwise.
    The second option (in which conformity demonstrations during the 
pre-SIP period must consider NOX only if the State or EPA 
make a finding that NOX is a significant contributor) is 
under consideration because the contribution of nitrates to total 
PM2.5 concentrations in different metropolitan areas can 
vary significantly as noted above. In addition, this option would 
enable states to consider NOX emission reductions in 
combination with potential reductions of VOCs, NH3 and 
SO2 as part of the process for developing an area's 
attainment demonstration (due within 3 years of the area's 
nonattainment designation), in which air quality modeling at a more 
refined spatial resolution (e.g. 12 kilometer grid size) would be 
performed. EPA seeks comment on the two options for addressing 
NOX in conformity prior to PM2.5 SIPs.
    VOC precursor emissions. In 1999, on-road sources accounted for 
approximately 34% of the total VOC emissions in the 372 potential 
nonattainment counties for PM2.5 (based on the 1999-2001 air 
quality data). Carbonaceous particles, which result, in part, from 
reactions involving VOCs, account for 25-70% of constructed fine 
particle mass measured at speciation trends network sites. The highest 
percentages of carbonaceous particles tend to be in California and the 
lowest percentages tend to be in the eastern United States.
    Our understanding of the role of VOCs in PM2.5 air 
quality problems continues to evolve. VOCs play several different 
functions in the formation of the organic fraction of PM2.5. 
The 2003 NARSTO report characterizes VOC precursors into three main 
categories. High molecular weight organic molecules (i.e., molecules 
with 25 or more carbon atoms) are either emitted directly as particles 
or as liquids that rapidly condense onto existing particles. 
Intermediate weight organic molecules (e.g., compounds with 7 to 24 
carbon atoms) often exhibit a range of volatilities and can exist in 
both the gas and aerosol phase. For this reason they are also referred 
to as semivolatile compounds. These compounds react at higher 
temperatures to form secondary organic aerosols (SOAs). Aromatic 
compounds such as toluene, xylene, ethyl benzene are considered to be 
the most significant anthropogenic SOA precursors and have been 
estimated to be responsible for 50 to 70 percent of SOAs. The smallest 
organic molecules (i.e., molecules with six or less carbon atoms) occur 
in the atmosphere mainly as vapors and typically do not form organic 
particles at ambient temperatures. However, they participate in 
atmospheric chemistry processes resulting in the formation of ozone and 
certain free radical compounds (such as the hydroxyl ion [OH]). These 
free radicals participate in the oxidation of other gas-phase compounds 
(such as semivolatile aromatics) to form SOAs. The relative importance 
of each of these groups of organic compounds in the formation of 
organic particles varies from area to area. Also, the contribution of 
on-road source emissions to each of these three groups of organic 
compounds may vary from area to area.
    Since on-road motor vehicles account for a substantial portion of 
total VOC emissions and on-road VOCs should be significant in many 
PM2.5 areas, one could argue that the first proposed option 
is the most logical and environmental approach. Under this proposed 
option, VOCs would be considered in conformity automatically unless 
states or the EPA Regions determine that VOCs are insignificant for a 
given area. On the other hand, it may be appropriate to allow states 
and EPA the opportunity to evaluate the local significance of VOC 
emissions prior to consideration in conformity, given the likely 
variations between areas regarding the role of VOCs in the formation of 
PM2.5. EPA seeks comment on the two options for addressing 
VOCs in conformity prior to PM2.5 SIPs.
    SOX precursor emissions. EPA believes that statutory 
requirements are met under both proposed options if SOX is 
only addressed in conformity if it is determined to be significant to 
an individual nonattainment area. Although SOX may 
significantly contribute to total PM2.5 in terms of 
emissions from all sources, emissions inventory data indicates that on-
road emissions of SOX generally represent a very small 
portion of the total SOX emissions. Emissions inventory data 
for 1999 for the 372 potential PM2.5 nonattainment counties 
for PM2.5 (based on 1999-2001 air quality data) shows that 
on-road sources were responsible for only 2% of total SOX 
emissions. By comparison, fuel combustion sources (e.g., electric 
utility and industrial combustion of coal and oil) were responsible for 
approximately 88% of the SOX emissions in 1999 in these same 
counties.
    In addition, EPA has already adopted two regulations that will 
greatly reduce emissions of SOx from on-road sources by the time such 
regulations are both in full effect in 2009. First, in 2004 the low 
sulfur gasoline program begins to be

[[Page 62708]]

phased in and is fully effective in 2007 (February 10, 2000, 65 FR 
6697). This regulation will reduce the sulfur content of gasoline by 
approximately 90%.\6\ Second, in 2006 the low sulfur diesel program 
begins to be phased in and is fully effective by 2009 (January 18, 
2001, 66 FR 5001). This regulation will reduce the sulfur content of 
diesel fuel by approximately 97% nationally.
---------------------------------------------------------------------------

    \6\ In addition, California has adopted its own rule which 
addresses the sulfur content of gasoline in that State. California's 
regulation is similar in stringency to the federal regulation.
---------------------------------------------------------------------------

    Projections of on-road emissions of SO2 in 2020 in the 372 
potential PM2.5 nonattainment counties based on 1999-2001 
air quality data indicates that on-road sources will be responsible for 
less than 1% of the total SO2 emissions in 2020 in these 
counties.\7\ These projections confirm that the implementation of the 
fuel regulations discussed above will ensure that SO2 
emissions from on-road sources remain at insignificant levels.
---------------------------------------------------------------------------

    \7\ EPA 420-R-00-020, October 2002, ``Procedures for Developing 
Base Year and Future Year Mass and Modeling Inventories for the 
Heavy-Duty Engine and Vehicle Standards and Highway Diesel Fuel 
(HDD) Rulemaking.''
---------------------------------------------------------------------------

    NH3 precursor emissions. EPA believes that both proposed options 
are appropriate and consistent with the statute by only requiring 
NH3 conformity analyses if it is found significant in a 
given area. States and EPA should have a better understanding of the 
effect of NH3 reductions on PM2.5 concentrations 
by 2007, when PM2.5 SIPs would be due. Based on the limited 
state of knowledge about on-road mobile source NH3 
contributions to PM2.5 and indications that such emissions 
may be small, EPA does not generally believe that any areas should be 
required to consider NH3 in conformity before SIPs are 
submitted, unless the State or EPA determines that NH3 
emissions are significant.
    First, the 2003 NARSTO-PM report states that in most areas, 
insufficient information exists at this time to predict how particle 
mass and composition would change in response to changing 
NH3 emissions. In some areas, reductions in NH3 
could actually lead to formation of acid aerosols that could worsen air 
quality. Second, existing emissions data show that on-road sources are 
a relatively small contributor to national NH3 emissions, 
approximately 5%. In addition, information on 1999 emissions indicates 
that about 17% of the NH3 in the 372 potential 
PM2.5 nonattainment counties (based on 1999-2001 air quality 
data) comes from on-road sources. Although this information provides 
some evidence that on-road NH3 emissions can be important in 
some urban areas, this is likely due to urbanized counties having fewer 
agricultural and other NH3 sources.

IX. Re-entrained Road Dust in PM2.5 Regional Emissions 
Analyses

A. Background

    Fugitive dust is released into the atmosphere by the mechanical 
disturbance of granular material. Common sources of fugitive dust 
include agricultural operations, construction, and on-road motor 
vehicle activity. Motor vehicles produce direct particulate emissions 
of dust through resuspension of loose material on the road surface, 
also known as re-entrained road dust.
    Re-entrained road dust can come from both paved and unpaved roads, 
including pavement wear and decomposition, atmospheric deposition onto 
the road surface, mud and dirt carry-out from off-road sites, and sand, 
salt, and other materials applied for ice or skid control. In the 
preamble to the 1993 final conformity rule, EPA identified re-entrained 
road dust as a potential on-road mobile source contributor to some 
local PM10 nonattainment problems. EPA stated, ``All highway 
and transit related source categories that contribute to the 
nonattainment problem should be identified and included in the motor 
vehicle emissions budget, including exhaust, evaporative, and re-
entrained dust emissions (including emissions from antiskid and deicing 
materials, where treated as mobile source emissions by the SIP).'' 
(November 24, 1993, 58 FR 62194)

B. What Are We Proposing?

    This part of the proposal addresses when direct PM2.5 
from re-entrained road dust would be included in conformity analyses in 
PM2.5 nonattainment and maintenance areas. Once a 
PM2.5 SIP is submitted, re-entrained road dust would be 
included in regional emissions analyses if road dust is considered 
significant in the context of the SIP's air quality modeling and 
included in an adequate or approved PM2.5 motor vehicle 
emissions budget. EPA would consider the significance of road dust in 
its adequacy review or approval of a submitted PM2.5 SIP. 
The following two options address road dust emissions in the time 
period before adequate or approved PM2.5 SIP budgets are 
established.
    The first option would require that, prior to adequate or approved 
PM2.5 SIP budgets, re-entrained road dust would only be 
included in regional emissions analyses if the State air quality agency 
or EPA Regional Administrator determines that re-entrained road dust is 
a significant contributor to the PM2.5 regional air quality 
problem. In other words, PM2.5 areas could presume that re-
entrained road dust is not a significant contributor and not include 
road dust in PM2.5 transportation conformity analyses prior 
to the SIP, unless the State or EPA finds road dust significant. The 
proposed regulatory text for this option can be found in Sec.  
93.102(b)(3).
    EPA requests comment on whether the first proposed option should be 
modified to require certain PM2.5 areas that are also 
PM10 areas to include road dust in PM2.5 
conformity analyses, if road dust is currently included in 
PM10 conformity analyses. Such a caveat would result in a 
limited number of PM2.5 areas including road dust in all 
PM2.5 conformity analyses prior to a PM2.5 SIP, 
unless the State or EPA found that road dust is not a significant 
contributor to the regional air quality problem. This proposal does not 
affect how re-entrained road dust is addressed in conformity for the 
PM10 standard.
    The second proposed option would require that re-entrained road 
dust be included in conformity analyses in all PM2.5 
nonattainment areas prior to adequate or approved PM2.5 SIP 
budgets, unless the State air quality agency or EPA Regional 
Administrator determines that re-entrained road dust is not a 
significant contributor to the regional air quality problem. For this 
option, MPOs and DOT would document in their conformity determinations 
that regional emissions analyses for direct PM2.5 do not 
include road dust emissions when EPA or the State has determined that 
such emissions are insignificant.\8\
---------------------------------------------------------------------------

    \8\ The public would be notified when road dust is considered 
insignificant through the documentation in a conformity 
determination for this option.
---------------------------------------------------------------------------

    An EPA or State air agency finding of significant or insignificant 
re-entrained road dust emissions (a ``significance finding'') would be 
based on a case-by-case review of the following factors for either 
proposed option: the contribution of road dust to current and future 
PM2.5 nonattainment; an area's current design value for the 
PM2.5 standard; whether control of road dust appears 
necessary to reach attainment; and whether increases in re-entrained 
dust emissions may interfere with attainment. Such a review would 
include consideration of local air quality data and/or air quality 
modeling results. Today's proposed options for PM2.5 road 
dust are consistent with EPA's existing

[[Page 62709]]

insignificance policy for all areas as described in Section XIV.B.
    Under either option, a significance finding should be made only 
after discussions with the interagency consultation group for the 
PM2.5 nonattainment area. These discussions should include a 
review of the data being considered. Interagency consultation would 
also ensure that all of the relevant agencies are aware that such a 
finding is being considered and is supported by the air quality 
information that is available at the time. A significance finding would 
be made through a letter to the relevant state and local air quality 
and transportation agencies, MPO(s), DOT, and EPA (in the case of a 
State air agency finding).
    EPA notes that any significance finding made prior to the SIP 
should not be viewed as the ultimate determination of the significance 
of road dust emissions in a given area. State and local agencies may 
find through the SIP development process that road dust emissions are 
significant and should be included in the PM2.5 SIP motor 
vehicle emissions budget and subsequent conformity analyses, even in 
the case where road dust emissions were previously considered 
insignificant.
    As described further below, under any of the proposed options, EPA 
would issue guidance on how to calculate PM2.5 road dust 
emissions to reflect the true impact of re-entrained road dust on 
regional air quality. This guidance would be available before EPA's 
final PM2.5 nonattainment designations. See Section IX.D. 
for more details on EPA's ideas for such guidance.

C. Why Are We Proposing These Options?

    At issue is the question of whether or not re-entrained road dust 
has a significant impact on air quality and should be included in 
conformity analyses in all PM2.5 areas. Existing 
PM10 areas include re-entrained road dust in conformity 
because fugitive dust from roadways and other sources dominate 
PM10 regional emissions inventories. However, the role of 
re-entrained road dust for PM2.5 air quality issues is less 
clear. Furthermore, there does not appear to be a direct correlation 
between the amount of road dust calculated for PM2.5 motor 
vehicle inventories and what is being collected on PM2.5 
monitoring filters, as discussed further in this section.
    Specifically, analysis of local air quality data indicates wide 
regional variation in the fractions of PM2.5 found on air 
quality monitors that consists of chemical elements associated with 
fugitive dust. Moreover, not all emissions of these chemical elements 
are attributable to re-entrained road dust, as they can also be emitted 
by other sources that disturb or process minerals or metals. In some 
areas, especially those areas in the eastern United States, preliminary 
analyses indicate that fugitive dust may not have a significant impact 
on regional air quality.\9\ In those areas, it may be more productive 
prior to a PM2.5 SIP to focus control efforts on vehicle 
emissions that contribute to the PM2.5 air quality problem, 
rather than on re-entrained road dust emissions.
---------------------------------------------------------------------------

    \9\ ``National Air Quality and Emissions Trends Report, 1999,'' 
EPA-454/R-01-004, U.S. EPA Office or Air Quality Planning and 
Standards, March 2001; also J. Szykman, D. Mintz, J. Creilson, and 
M. Wayland, ``Impact of April 2001 Asian Dust Event on Particulate 
Matter Concentrations in the United States,'' in the ``Proceedings 
of the Air & Waste Management Association Symposium on Air Quality 
Measurement Methods and Technology, San Francisco, November 13-15, 
2002.
---------------------------------------------------------------------------

    The first proposed option would address regional variability, and 
ultimately allow the SIP's analysis to determine whether or not re-
entrained road dust is a significant factor in the regional 
PM2.5 problem. A more thorough air quality analysis as 
required for the SIP may be the best determination of the real impact 
of re-entrained road dust on PM2.5 air quality, unless there 
is clear evidence before the SIP that road dust emissions are 
significant.
    Under the first proposed option, EPA is requesting comment on 
whether it is appropriate to require PM2.5 areas that are 
also PM10 areas to include road dust in conformity analyses, 
unless a finding is made that road dust is not significant. Areas that 
are nonattainment for PM10 may be more likely to have 
significant re-entrained road dust contributing to the PM2.5 
problem. Due to the significant amount of road dust in existing 
PM10 inventories, it may be appropriate to also initially 
presume that road dust is significant for PM2.5 for these 
limited number of PM10 areas, unless the State or EPA find 
that road dust is not significant.
    Finally, because the second option begins with the presumption that 
re-entrained road dust emissions is a problem, it may be more 
conservative in protecting PM2.5 air quality with respect to 
the impact of road dust. However, in many areas, the second proposed 
option might result in the diversion of resources toward road dust 
analyses as well as road dust control measures that might be more 
effectively used to understand and control other emissions sources. 
These areas do have the option of supporting an EPA or state finding 
that road dust emissions are not significant, but this may be difficult 
to do prior to the completion of the SIP analysis in some areas.

D. Request for Comment on Estimating Road Dust Emissions

    Under any of the proposed options, road dust SIP emissions 
inventories and regional emissions analyses for conformity at this time 
should be calculated using methods described in EPA's guidance 
entitled, ``AP-42, Fifth Edition, Volume 1, Chapter 13, Miscellaneous 
Sources'' (US EPA Office of Air Quality Planning and Standards; 
available at http://www.epa.gov/ttn/chief/ap42/ch13/ ) or locally 
developed estimation methods approved through the interagency 
consultation process. For reasons described below, under EPA's future 
guidance, calculated emissions would then be adjusted downward based on 
an analysis of the relative impact of re-entrained road dust on ambient 
PM2.5 concentrations as determined by regional air quality 
monitors in a given area.
    Review of PM2.5 air quality data raises significant 
questions of uncertainty in the estimation methods for PM2.5 
dust emissions. Emissions of road dust are estimated using methods that 
are based on data collected from particulate monitors set up close to 
the road edge. These methods are used to create a PM2.5 
inventory, which is an estimation of the total amount of 
PM2.5 road dust released into the atmosphere. When used with 
standard air quality simulation models, the methods that are used to 
create the inventory may adequately estimate the dust in the air 
immediately adjacent to the road, but may overestimate the impact that 
dust has on concentrations in the larger region and in particular at 
the PM2.5 monitors that determine attainment with the 
PM2.5 NAAQS. Regional air quality is assessed by air quality 
monitors that are set up in a wide range of locations. These regional 
air quality monitors generally indicate much lower fractions of dust in 
the atmosphere than are predicted based on the emissions inventories. 
(``Reconciling Urban Fugitive Dust Emissions Inventory and Ambient 
Source Contribution Estimates: Summary of Current Knowledge and needed 
Research'', Desert Research Institute Document 6110.4F, May 2000, 
available at http://www.epa.gov/ttn/chief/efdocs/fugitivedust.pdf).
    There are several likely contributing factors to explain this 
discrepancy. The first factor is that road dust particles are 
distributed more toward the high end of the PM2.5 size range 
than are exhaust particle or PM2.5 emissions from many other 
source types. The second factor is

[[Page 62710]]

the low height to which re-entrained road dust is lifted (75% of 
unpaved road dust emissions were less than 2 meters above the ground 
when they were measured; compared to emissions released from stacks at 
stationary sources or vertical exhaust pipes on heavy-duty trucks) 
(Desert Research Institute Document 6110.4F, May 2000). This low-
lifting height provides an extended ``opportunity'' for impaction, 
filtration, agglomeration and other physical mechanisms that lead to 
particle removal to occur. The third factor is that the lack of any 
thermal buoyancy for dust emissions would somewhat reduce their impact, 
in contrast to emissions from vehicle exhaust and other combustion or 
high temperature sources. All three factors increase the likelihood 
that road dust particles would settle out of the atmosphere onto the 
ground or adhere onto other surfaces such as vegetation, structures, 
etc., before contributing substantially to the PM2.5 
regional air quality problem.
    There are other reasons for uncertainty associated with the current 
method for estimating PM2.5 re-entrained road dust 
emissions. The original data used to develop this method were based on 
measurements of PM10 rather than PM2.5. The 
PM10 data were subsequently adjusted to reflect the fraction 
of PM2.5 in PM10, but these adjustments add 
uncertainty. In addition, the data used to develop the emissions 
estimation method are highly variable. This variability adds to 
uncertainty about its interpretation. (``AP-42, Fifth Edition, Volume 
1, Chapter 13: Miscellaneous Sources'', U.S. EPA Office of Air Quality 
Planning and Standards).
    Attempting to adjust for discrepancies between estimated 
inventories and air quality measurements, EPA has discounted national 
PM2.5 emissions inventories by 75% in air quality analyses 
for recent EPA rulemakings and other national analyses, to create the 
``effective emissions'' that are used as input into regional air 
quality models. (Desert Research Institute Document 6110.4F, May 2000). 
Even with this discount, absolute air quality model predictions of the 
concentration of chemical elements associated with road dust typically 
have remained higher than observed at most urban PM2.5 
monitoring sites, suggesting that an even larger discount may be needed 
in at least some situations. In areas where PM2.5 
transportation conformity for road dust is required, we believe that 
discounting local re-entrained road dust inventories is necessary to 
ensure that the overall impact of road dust is properly estimated, and 
that decisions about control strategies for road dust emissions and 
exhaust emissions reflect actual relative impacts on ambient 
concentrations and attainment. Without these adjustments, planners may 
not apply the proper combination of control measures on dust and 
vehicle emissions needed to properly address the regional 
PM2.5 air quality problem. Based on observed discrepancies, 
EPA believes that controls on road dust would have a much smaller 
impact on regional air quality than would initially appear based on 
unadjusted emission inventories.
    Preliminary analysis of air quality data and modeling studies 
indicates that there will likely be wide local variation in the size of 
the necessary adjustments to PM2.5 dust emissions. For this 
reason, it would be inappropriate to apply EPA's 75% downward 
adjustment for national inventories for all areas. EPA believes it is 
more appropriate for PM2.5 areas to create locally-specific 
adjustments based on the amount of road dust on an area's monitoring 
filters and its relationship to an area's nonattainment problem. 
Therefore, EPA intends to develop methods to make these adjustments 
locally both before and after a regional SIP air quality analysis has 
been done. EPA would issue this guidance by the time PM2.5 
designations are made. EPA invites comments and suggestions for 
possible methods for determining such local adjustments in areas where 
road dust is included in conformity analyses.

X. Construction-Related Fugitive Dust in PM2.5 Regional 
Emissions Analyses

A. Background

    Construction-related fugitive dust is granular material released 
into the atmosphere during construction. Activities associated with 
construction-related fugitive dust emissions include land clearing, 
drilling and blasting, ground excavation, cut and fill operations (i.e. 
earth moving), and facility construction. Often, a large portion of 
such emissions results from equipment traffic over temporary roads at 
the construction site. Construction-related fugitive dust is distinct 
from re-entrained road dust, which is emitted by motor vehicles 
traveling over permanent paved or unpaved roads. The discussion here 
applies only to fugitive dust emitted during the construction of 
highway or transit projects.

B. What Are We Proposing?

    EPA proposes to include construction-related fugitive dust from 
highway or transit projects in regional emissions analyses in 
PM2.5 nonattainment and maintenance areas only if the SIP 
identifies such dust as a significant contributor to the regional air 
quality problem. In other words, PM2.5 areas would only 
include construction-related fugitive dust if the SIP identifies it as 
contributing to an area's air quality problem. Construction-related 
dust emissions would not be included in any PM2.5 conformity 
analyses before adequate or approved PM2.5 SIP budgets are 
established. EPA has included proposed regulatory text for this option 
as Sec.  93.122(e).
    Under this proposal, if construction-related fugitive dust is 
included in transportation conformity, we propose to allow 
PM2.5 SIP budgets and conformity analyses to be adjusted to 
reflect the true impact of construction-related fugitive dust on 
regional air quality, as explained in Section IX.D. EPA would issue 
guidance on how to calculate PM2.5 construction dust 
emissions to more accurately reflect the impact of construction dust on 
regional air quality before EPA's final PM2.5 nonattainment 
designations. Construction dust SIP emissions inventories and regional 
emissions analyses for conformity should be calculated using methods 
described in EPA's guidance entitled, ``AP-42, Fifth Edition, Volume 1, 
Chapter 13, Miscellaneous Sources'' (US EPA Office of Air Quality 
Planning and Standards; available at http://www.epa.gov/ttn/chief/ap42/ch13/) or locally developed estimation methods approved through the 
consultation process.
    Under EPA's future guidance, calculated emissions would then be 
adjusted downward to account for discrepancies based on an analysis of 
the relative impact of construction dust on ambient PM2.5 
concentrations as determined by regional air quality monitors in a 
given area. See previous discussion in Section IX.D. for more details 
on ideas that EPA is considering for its future guidance. EPA is also 
requesting comment from the public on such guidance.

C. Why Are We Proposing This Option?

    Section 176(c) of the Clean Air Act requires that the air quality 
impacts of transportation projects be evaluated so that new violations 
or worsened violations do not occur. If emissions of fugitive dust from 
highway or transit projects contribute to air quality problems in 
PM2.5 areas and as a result, air quality is worsened, then 
it may be appropriate to evaluate those emissions in conformity before 
federal funding or approval is given. Section 93.122(d) of the 
transportation conformity rule

[[Page 62711]]

requires regional PM10 emissions analyses to include 
construction-related PM10 dust if the SIP identifies such 
emissions as a contributor to the nonattainment problem. If 
construction-related fugitive PM10 is not identified as a 
contributor to the air quality problem in the implementation plan, 
areas are not required to include these emissions in the regional 
emissions analysis for transportation conformity. The proposal applies 
the current rule's approach for PM10 areas to 
PM2.5 areas.
    In nonattainment and maintenance areas where construction-related 
fugitive dust is a part of the nonattainment problem, we would allow 
states to adjust the construction-related fugitive dust SIP inventories 
and subsequent conformity analyses to resolve any discrepancies between 
the dust inventories and the amount of dust observed at air quality 
monitors, as described above. As noted, regional air quality monitors 
generally indicate much lower fractions of dust in the atmosphere than 
are predicted based on the emissions inventories. (Desert Research 
Institute Document 6110.4F, May 2000). As explained above, factors such 
as larger particle size, low release height, and low thermal buoyancy 
increase the likelihood that dust particles would quickly settle out of 
the atmosphere onto the ground or adhere onto other surfaces such as 
vegetation, structures, etc.
    In areas where PM2.5 transportation conformity for 
construction dust is required, we believe that discounting local 
construction dust inventories is necessary to ensure that the overall 
impact of road dust is properly estimated, and that decisions about 
control strategies for dust emissions (including construction dust) and 
exhaust emissions reflect actual relative impacts on ambient 
concentrations and attainment. EPA will develop separate guidance for 
these adjustments to SIP budgets and conformity analyses and this 
guidance would be available before EPA's final nonattainment 
designations for the PM2.5 standard.

D. Implementation and Request for Additional Information

    EPA addressed implementation issues for including construction dust 
in PM10 conformity analyses in an October 28, 1996 
memorandum.\10\ Under the proposal, EPA would apply similar 
implementation guidance to PM2.5 areas.
---------------------------------------------------------------------------

    \10\ ``Transportation Conformity: Regional Analysis of 
PM10 Emissions from Highway and Transit Project 
Construction,'' memorandum from Gay MacGregor, then-director, 
Regional and State Programs Division, Office of Mobile Sources to 
EPA Regional Air Division Directors.
---------------------------------------------------------------------------

    During the development of the SIP, air quality agencies would 
ensure that the PM2.5 SIP inventory clearly identifies the 
role (if any) of construction dust in the PM2.5 air quality 
problem. If construction dust is a contributor, dust from highway and 
transit projects would be included in the PM2.5 SIP motor 
vehicle emissions budget. MPOs and state transportation agencies would 
work together with local and state air quality agencies to ensure that 
construction dust emissions are properly analyzed with respect to the 
transportation plan and TIP for conformity analyses. If the 
PM2.5 SIP identifies construction dust as a significant 
PM2.5 problem, the regional emissions analysis would account 
for the level of construction activity, the fugitive PM2.5 
control measures in the SIP (if there are any), and the dust-producing 
capacity of the proposed construction activities.

XI. Compliance With PM2.5 Control Measures

A. What Are We Proposing?

    We are proposing that FHWA and FTA projects in PM2.5 
nonattainment and maintenance areas must comply with the applicable 
SIP's control measures, when such measures exist. Through this 
proposal, FHWA/FTA would assure implementation of a required control or 
mitigation measure by obtaining enforceable written commitments from 
the project sponsor and/or operator prior to making a project-level 
conformity determination. This requirement would be satisfied if the 
project-level conformity determination contains a written commitment 
from the project sponsor to include the control measures in the final 
plans, specifications and estimates for the project. This proposal is 
consistent with a similar requirement for PM10 areas in 
Sec.  93.117 of the current conformity rule.
    We should note, however, that this proposed requirement in Sec.  
93.117 is only applicable after a PM2.5 nonattainment area 
has an approved PM2.5 SIP, since the requirement is to 
comply with the measures in the approved SIP. Today's proposal does not 
affect any separate state or SIP requirements for compliance with 
control measures.
    The purpose of a PM2.5 control measure would be to limit 
the amount of PM2.5 emissions from construction activities 
and/or normal use and operation associated with the project. Examples 
of control or mitigation measures that may be approved into a SIP 
include limitations on fugitive dust during construction or street 
sweeping. Normal project design elements (dimensions, lane widths, 
materials, etc.), however, are not considered mitigation or control 
measures.
    EPA requests information from current PM10 nonattainment 
and maintenance areas on how the current requirement in Sec.  93.117 
has been implemented in PM10 areas and what types of 
measures have been effective in limiting these emissions. Information 
on how PM10 areas have addressed this requirement and the 
types of measures that have been implemented could prove valuable to 
new PM2.5 nonattainment areas.

B. Why Are We Proposing This Option?

    The purpose of conformity is to ensure that federal actions are 
consistent with the SIP. If the approved SIP includes control measures 
for mitigating PM2.5 emissions from federal transportation 
projects, then conformity should ensure that these SIP measures are 
implemented. We believe that this requirement would help 
PM2.5 areas achieve clean air by ensuring that federal 
projects comply with control measures that result in air quality 
improvements as anticipated in the SIP. Although such projects must 
comply with SIP requirements in any event, documenting compliance in a 
conformity determination would add an important enforcement tool to aid 
in SIP compliance.
    The interagency consultation process is required to discuss the 
inclusion of control measures in an area's SIP. Section 93.105(b)(1) of 
the current conformity rule requires that the interagency consultation 
process be used in the development of the SIP, particularly when an 
agency is responsible ``for developing, submitting or implementing 
provisions of an implementation plan.'' The interagency consultation 
group may also be a source of recommendations for the most appropriate 
approach to addressing PM2.5 emissions in the SIP.
    Section 93.117 of the current conformity rule has an identical 
requirement for project-level conformity determinations in 
PM10 nonattainment and maintenance areas. We do not believe 
that compliance with this requirement has been a burden for 
PM10 areas. Therefore, we do not anticipate that our 
proposal in Sec.  93.117 should be a burden on new PM2.5 
nonattainment areas, as this requirement simply ensures that control 
measures which the interagency consultation group has

[[Page 62712]]

previously agreed upon and included in the SIP are implemented.

XII. PM2.5 Hot-Spot Analyses

A. What Are We Proposing?

    EPA is taking comment on two options concerning the need to conduct 
hot-spot analyses for FHWA and FTA projects in PM2.5 
nonattainment and maintenance areas. A hot-spot analysis as defined in 
Sec.  93.101 of the rule for CO and PM10 areas is an 
estimation of likely future localized pollutant concentrations and a 
comparison of those concentrations to the air quality standard. A hot-
spot analysis assesses impacts on a scale smaller than the entire 
nonattainment or maintenance area, including for example, congested 
roadway intersections and highways or transit terminals, and uses a 
dispersion model to determine the effects of emissions on air quality. 
In general, a hot-spot analysis must show that the project does not 
cause any new violations of the air quality standard or increase the 
frequency or severity of existing violations. The conformity rule 
currently requires hot-spot analyses in CO and PM10 
nonattainment and maintenance areas. The reader should refer to 
Sec. Sec.  93.116 and 93.123 of the current conformity regulation for 
specific CO and PM10 hot-spot analysis requirements.
    The first proposed option would not require hot-spot analyses for 
FHWA and FTA projects in PM2.5 nonattainment and maintenance 
areas, for the reasons described below. We recognize that there is on-
going research on PM2.5 and, if this research provides 
evidence in the future that clearly indicates that transportation-
related PM2.5 hot-spots exist, we would revise the 
conformity rule in the future to require PM2.5 hot-spot 
analyses at locations that are most likely to experience hot-spot 
problems. We invite commenters with data relevant to the existence of 
transportation-related PM2.5 hot-spots to submit this data 
during the comment period for this proposal.
    EPA also requests comment on a second option that would require 
PM2.5 hot-spot analyses for FHWA and FTA projects at certain 
types of locations if the PM2.5 SIP for the area identifies 
such locations. Under this option, PM2.5 hot-spot analyses 
would not be required for any projects prior to the submission of a SIP 
and then only if the PM2.5 SIP identifies susceptible types 
of locations.
    We request comment on what potential PM2.5 hot-spot 
location types could be identified in the SIP, including locations of: 
significant congestion, highest traffic volumes, existing or suspected 
future localized violations of the PM2.5 standard, or high 
diesel vehicle traffic such as near freight or transit terminals. EPA 
seeks comment on these potential location types or others that may be 
appropriate to consider for the second proposed option. The locations 
listed above are similar to those described in Sec. Sec.  
93.123(a)(1)(i)-(iv) and 93.123(b)(1)(i)-(iii) of the current 
conformity rule where quantitative hot-spot analyses must be performed 
for CO and PM10. However, under this proposal, 
PM2.5 hot-spot analyses would only be required for projects 
at the types of locations identified in the SIP. This option would not 
require qualitative analyses for all projects in the PM2.5 
nonattainment or maintenance area as is currently required for CO and 
PM10 nonattainment and maintenance areas.
    If the second option is finalized, the required hot-spot analysis 
would address only the contribution of directly emitted particles to 
ambient PM2.5 concentrations, including re-entrained 
emissions if those are addressed under conformity in that area. 
Typically, a hot-spot analysis would be done for an intersection, a 
short segment of roadway or the immediate vicinity of a transit 
terminal. Since secondary particles take several hours to form in the 
atmosphere giving emissions time to disperse beyond the immediate area 
of concern, hot-spot analyses could only examine direct particulate 
emissions that are attributable to an individual project. In other 
words, precursor emissions from a project would not be considered in a 
hot-spot analysis. Secondary particles would only be considered as part 
of the PM2.5 background concentration that would be included 
in the assessment of whether or not a hot-spot exists.
    If EPA finalizes the second option, we would provide guidance on 
how to identify locations where transportation-related PM2.5 
hot-spots may exist. This guidance would be available for use when 
states prepare PM2.5 SIPs. We would also provide guidance 
and appropriate models for carrying out quantitative analyses at 
identified locations of concern, prior to the requirement to perform 
any PM2.5 hot-spot analyses.
    Finally, under the second option we are also proposing that prior 
to making a project-level conformity determination in a 
PM2.5 nonattainment or maintenance area, FHWA or FTA must 
obtain from the project sponsor and/or operator enforceable written 
commitments to implement any required control or mitigation measures 
otherwise applicable to the project. These control or mitigation 
measures may be a condition of either a NEPA approval or a conformity 
determination for a plan or TIP or be included in the design concept 
and scope of the project that is used in the regional emissions 
analysis required by Sec. Sec.  93.118 or 93.119. These measures may be 
applicable during construction and/or operation of the project. Such 
measures would already be applicable to such projects, however 
including commitments to them in conformity determinations will provide 
an additional enforcement tool. Section 93.125(a) of the conformity 
rule already includes this requirement for CO and PM10 
nonattainment and maintenance areas, and EPA would include similar 
language if a PM2.5 hot-spot analysis requirement is 
included in the final rule. Although EPA has not proposed regulatory 
language, either of these proposals could be finalized as described 
above.

B. Existing Research on PM2.5 Hot-Spots and Request for 
Additional Information

    EPA has reviewed a number of key studies that represent the range 
of research that is currently available on the impact of on-road mobile 
source emissions of particles on air quality near roadways. The results 
of these studies are not conclusive as to whether or not 
transportation-related PM2.5 hot-spots exist. The majority 
of these studies indicate that concentrations of some components of 
PM2.5 increase near roadways, such as black carbon and 
ultrafine particles. However, it is difficult to relate these measures 
directly to PM2.5, as many of the studies did not measure 
PM2.5 directly. The magnitude of increased concentrations 
appears to be related to several factors including the total number of 
vehicles operating on the roadway, the number of diesel vehicles 
operating on the roadway and the level of congestion or amount of stop-
and-go driving on the roadway. However, these studies were less clear 
as to whether or not PM2.5 hot-spots exist. Several studies 
concluded that on-road sources were one of several contributors to the 
concentrations measured near roadways. At least one study concluded 
that hot-spots do not exist. Several studies reported that they had 
identified hot-spots caused by local on-road emissions. However, it is 
difficult to relate the conclusions of many of these studies to the 
PM2.5 standards, because a number of these studies collected 
individual air quality samples for less than 24 hours and only 
collected data over a period of several months. All of the studies that 
were reviewed are available in the docket for this rulemaking. We 
invite others with

[[Page 62713]]

data relevant to the existence of transportation-related hot-spots to 
submit their data during the comment period for this rulemaking.

C. Why Are We Proposing These Options?

    Section 176(c)(3)(B)(ii) only specifically requires a hot-spot 
analysis for projects in CO nonattainment areas. Since Congress only 
specifically required hot-spot analyses in CO areas, EPA has discretion 
to decide if hot-spot analyses are necessary to protect air quality in 
particulate matter nonattainment and maintenance areas. If EPA 
determines that analyses are necessary for a given particulate matter 
standard, EPA also has discretion to target such analyses toward 
certain locations or certain types of projects. Given the uncertainty 
found in the literature on the existence of PM2.5 hot-spots, 
we are proposing two options which are described below.
    If PM2.5 hot-spots are not expected to occur, the Clean 
Air Act's conformity provisions are met without performing hot-spot 
analyses in PM2.5 areas. Section 176(c)(1)(B) of the Clean 
Air Act requires that activities funded or approved by the federal 
government must not ``cause or contribute to any new violation of any 
standard in any area; increase the frequency or severity of any of any 
existing violation of any standard in any area; or delay timely 
attainment of any standard or any required interim emission reductions 
or other milestones in any area.'' For projects in ozone areas, we have 
previously determined that the requirements of section 176(c)(1)(B) are 
met if the project meets the requirements of section 176(c)(2)(C) of 
the Clean Air Act, since ozone impacts occur at a regional level. 
Section 176(c)(2)(C) indicates that a project may be adopted or 
approved if it is included in a conforming plan and TIP, the design 
concept and scope of the project has not changed significantly since 
the conformity finding for the plan and TIP, and the design concept and 
scope of the project was adequate to determine emissions when the 
conformity determination was made.
    Because projects in PM2.5 nonattainment and maintenance 
areas would be included in the area's regional emission analysis, as 
discussed in Section VII. of this proposal, they would also conform 
without a hot-spot analysis, if hot-spots are not expected to occur. 
Available air quality data indicate that PM2.5 air quality 
problems are similar to ozone in that they are both primarily regional 
in nature.
    EPA's January 2001 draft SIP guidance entitled ``Guidance for 
Demonstrating Attainment of Air Quality Goals for PM2.5 and 
Regional Haze'' indicates that, due to the nature of the 
PM2.5 NAAQS, sharp concentration gradients that lead to hot-
spots are unlikely because: individual air quality samples are 
collected over a 24-hour period; compliance with the annual 
PM2.5 standard is determined over a 3-year period; and, 
secondary formation of particles plays a significant role in 
determining PM2.5 concentrations in a given area.
    Therefore, we are proposing the first option (that would not 
require hot-spot analyses) because we are not certain that hot-spots 
will occur, and in that case hot-spot analyses would not be needed to 
protect air quality. If evidence clearly indicates that transportation-
related PM2.5 hot-spots exist, we would revise the 
conformity rule in the future to require PM2.5 hot-spot 
analyses at locations that are most likely to experience hot-spot 
problems.
    The second option would require hot-spot analyses at certain types 
of locations if the PM2.5 SIP identified locations 
susceptible to PM2.5 hot-spots. As discussed above, the 
results of research on transportation-related PM2.5 hot-
spots is inconclusive as to whether or not PM2.5 hot-spots 
exist or would exist in the future. However, most of the research we 
have reviewed indicates that concentrations of some components of 
PM2.5 increase near heavily traveled roadways. If a state 
identified types of locations in its SIP where it had evidence that a 
PM2.5 hot-spot exists or is likely to exist, a quantitative 
PM2.5 hot-spot analysis would be required for FHWA and FTA 
projects at these locations.
    This option would be consistent with the purpose of conformity, 
which is to ensure that federally funded or approved transportation 
projects are consistent with the SIP for the area. Requiring a hot-spot 
analysis for projects at these locations would also be environmentally 
protective because, if the planned project would cause a new violation 
or increase the frequency or severity of an existing violation, a 
project-level conformity determination would ensure that the estimated 
air quality impacts of the project would be mitigated. Also, the 
requirement for a hot-spot analysis would only result in an increased 
resource burden for conformity if the SIP for the area identified 
locations where the analyses would be required, and then only if a 
project was planned for one of these locations. This option would be an 
environmentally protective way of responding to the scientific 
uncertainty surrounding PM2.5 hot-spots, because it retains 
a mechanism to address PM2.5 hot-spots if states ultimately 
determine there could be potential problems. At the same time, it would 
impose no conformity resource burden prior to PM2.5 SIPs in 
any area; additional conformity resources would be required only in the 
case where an individual area identifies PM2.5 hot-spots as 
a local air quality issue in the SIP.
    In the event that the existence of PM2.5 hot-spots is 
confirmed, we do not believe that performing a qualitative hot-spot 
analysis for every FHWA and FTA project in PM2.5 
nonattainment and maintenance areas would provide an environmental 
benefit due to the regional nature of PM2.5 and the 
significant role of secondary formation of these fine particles. In 
addition, we recognize that performing a hot-spot analysis for every 
project in a PM2.5 nonattainment or maintenance area would 
require a significant amount of resources, which may not result in 
environmental benefits. Therefore, we are proposing that hot-spot 
analyses not be required for PM2.5, or in the second option 
that quantitative hot-spot analyses only be required for project 
locations if identified as a concern in the PM2.5 SIP.

XIII. PM10 Hot-spot Analyses

A. What Are We Proposing?

    EPA is requesting comment on whether to retain the current 
conformity rule's requirement that hot-spot emissions analyses be 
conducted for FHWA and FTA projects in all PM10 
nonattainment and maintenance areas. A PM10 hot-spot 
analysis is required to examine the localized impacts of an individual 
highway or transit project as required in Sec. Sec.  93.116 and 93.123, 
including all direct emissions from vehicle and re-entrained road dust.
    We are considering a wide range of options for modifying the 
current PM10 hot-spot analysis requirements, and no 
regulatory text is being proposed for any option. However, based on 
this proposal and any comments submitted, we may finalize any of the 
options discussed in this proposal. We also invite commenters to 
suggest additional options.
    One option is to maintain the current conformity rule requirements. 
These provisions require a hot-spot analysis for FHWA/FTA projects in 
PM10 nonattainment and maintenance areas to ensure that the 
project does not cause or contribute to any new localized 
PM10 violation or increase the frequency or severity of any 
existing PM10 violation.

[[Page 62714]]

There currently is no federal guidance for conducting quantitative 
PM10 hot-spot analyses, although qualitative guidance, 
developed by FHWA in consultation with EPA, is available.\11\ Local 
areas can develop their own procedures that meet the rule's 
requirements.
---------------------------------------------------------------------------

    \11\ Guidance for Qualitative Project-Level ``Hot Spot'' 
Analysis in PM10 Nonattainment and Maintenance Areas. 
Federal Highway Administration. Office of Natural Environment. 2001.
---------------------------------------------------------------------------

    EPA is also considering other options that would result in 
PM10 hot-spot analyses only being required under certain 
circumstances. For example, it may be appropriate to only require 
PM10 hot-spot analyses in nonattainment and maintenance 
areas where the SIP has identified motor vehicle emissions as a 
localized problem. Alternatively, under this option, hot-spot analyses 
would not be required in a PM10 area if the SIP has 
determined that motor vehicle emissions do not create a localized 
problem.
    Another option would be to only require PM10 hot-spot 
analysis at certain types of project locations (e.g., highly congested 
intersections) or for certain types of highway and/or transit projects 
(e.g., large transit stations where significant traffic and engine 
idling occurs). Such an option would be similar to the alternate option 
being proposed for hot-spot analyses for projects in PM2.5 
nonattainment and maintenance areas in Section XII. of today's 
proposal. EPA is requesting information on any existing PM10 
SIPs that identify motor vehicle emissions or specific locations as a 
hot-spot concern.
    We also request comment on an option that would delete 
PM10 hot-spot requirements from the conformity rule. When 
the transportation conformity rule was first promulgated in 1993, EPA 
was primarily concerned about the possibility of localized 
PM10 exceedances in urban street canyons or near transit 
terminals (November 24, 1993, 58 FR 3780). However, since other factors 
affecting PM10 emissions have changed since 1993, as 
discussed below, it may be appropriate to delete the current 
PM10 hot-spot requirement entirely and focus limited state 
and local resources on other air quality concerns.
    We are soliciting information on how PM10 hot-spot 
analyses have been completed to date; whether PM10 hot-spots 
have been detected from all or certain types of transportation 
projects; and whether stakeholders believe the current requirements 
result in environmental benefits. It has been 10 years since the 
current PM10 hot-spot analysis requirements were 
promulgated, and our understanding of PM10 air quality 
issues has improved over that time.
    We also invite commenters to submit the results of recent research, 
reports or data collection that would provide information on the nature 
of PM10 hot-spots and on appropriate methods for performing 
hot-spot analyses. For example, we are aware that the Transportation 
Center at the University of Tennessee conducted a series of analyses at 
various types of public transit facilities to determine their impact on 
nearby PM10 concentrations. None of these analyses showed 
that there was a significant risk of localized PM10 problems 
as a result of emissions from these facilities.
    Finally, we would also like to receive information on whether any 
PM10 problems have been identified through PM10 
qualitative analyses and how the identified problems were resolved for 
project level conformity determinations.

B. Why Are We Considering These Options?

    EPA believes that it is appropriate to re-evaluate the need for 
hot-spot analyses for all projects in PM10 nonattainment and 
maintenance areas at this time. When the conformity rule was 
promulgated in 1993, we interpreted the Clean Air Act section 
176(c)(1)(B) to require PM10 hot-spot analyses because of 
the requirement to ensure that transportation activities do not worsen 
air quality (January 11, 1993, 58 FR 3776). Section 93.116 of the 
current rule states that transportation projects cannot cause or 
contribute to new violations or increase the frequency or severity of 
existing ones.
    It should be noted that Clean Air Act section 176(c)(3)(B)(ii) only 
specifically requires hot-spot analyses for projects in CO 
nonattainment areas. Congress did not specifically require hot-spot 
analyses for PM10 areas. Therefore, if EPA concludes in this 
rulemaking that PM10 hot-spots are not an air quality 
concern or that PM10 hot-spots are only a concern in certain 
cases, then a rule revision would be consistent with the statute.
    In 1993, EPA believed that typically sized bus terminals or 
transfer points would not create PM10 hot-spots but that it 
was practical to require a determination to that effect. We also 
believed at that time that direct PM10 emissions would be 
capable of causing violations only in conditions of unusually heavy 
diesel truck/bus traffic and limited dispersion, such as street canyons 
(January 11, 1993, 58 FR 3780).
    We are not aware of any such locations that are currently causing 
localized PM10 exceedances. As stated previously, the 
University of Tennessee study did not show a risk of localized 
PM10 problems as a result of emissions from public transit 
facilities. We are requesting information on whether other studies on 
this issue are available.
    In addition, EPA's diesel fuel and engine standards (January 18, 
2001, 66 FR 5002) will significantly impact the amount of particulate 
emissions that will be emitted by new diesel vehicles. The fuel 
standards will be implemented in 2006 and the engine standards in 2004 
with more stringent standards starting in 2007. These standards may 
address EPA's original concern about the potential of localized 
PM10 hot-spots in certain urban or transit locations where 
diesel vehicle traffic is significant. Currently, agencies are required 
to perform such analyses on all projects regardless of their likelihood 
to produce a localized exceedance. However, areas that were at risk in 
the past may not be at risk in the future as the new vehicle and fuels 
standards take effect. Therefore, as vehicles and fuels become cleaner 
through fleet turnover, the likelihood of a PM10 hot-spot at 
any given location may be reduced.
    However, we are not proposing a preferred option for changing the 
current PM10 hot-spot requirements. Instead, we are 
soliciting input to guide our decision on maintaining, amending or 
eliminating the PM10 hot-spot requirements in the final 
rule. EPA believes it is appropriate to focus conformity resources 
where air quality issues are significant and need to be in place to 
address Clean Air Act section 176(c)(1)(B). A review of recent 
information may show either that PM10 hot-spot analyses are 
no longer warranted or that they can be better targeted at projects or 
locations where these types of problems may occur. We expect that the 
comments that we receive in response to this portion of the proposal 
would allow us to make appropriate changes to the existing requirements 
in the final rule, if necessary.

XIV. Miscellaneous Revisions for New and Existing Areas

A. Definitions

    EPA is proposing to clarify the current conformity rule's 
definitions for ``control strategy implementation plan revision'' and 
``milestone'' in Sec.  93.101. The current rule defines a control 
strategy implementation plan revision as an implementation plan which 
contains specific strategies for

[[Page 62715]]

controlling emissions and reducing ambient levels of pollutants to 
satisfy certain Clean Air Act requirements for reasonable further 
progress and attainment. The conformity regulation lists these Clean 
Air Act requirements as: Sections 182(b)(1), 182(c)(2)(A), and 
182(c)(2)(B) for ozone areas; section 187(a)(7) for CO areas; sections 
189(a)(1)(B) and 189(b)(1)(A) for PM10 areas; and sections 
192(a) and 192(b) for NO2 areas.
    EPA has determined, however, that the current list of Clean Air Act 
provisions in Sec.  93.101 is incomplete, as the list does not include 
all the provisions of the Act that require a control strategy SIP 
revision for the purposes of demonstrating reasonable further progress 
or attainment. For example, the current rule definition does not 
include Clean Air Act section 172(c) that includes the general plan 
provisions that any attainment or reasonable further progress SIP 
revision must satisfy. In addition, the conformity rule's definition 
does not address SIP revisions submitted under Clean Air Act sections 
187(g) or 189(d). These provisions of the Act require serious CO and 
PM10 areas, respectively, to submit SIP revisions that would 
reduce emissions by 5% per year until attainment of the relevant 
standard is ultimately achieved (``5% plans''), if these areas 
initially fail to attain on time.
    In implementing the conformity regulation, EPA has always 
interpreted the definition of a control strategy SIP revision to 
consist of any SIP that is established for the purposes of attainment 
or progress towards attainment, including those SIPs submitted to 
satisfy Clean Air Act sections 172(c), 187(g) or 189(d). Therefore, in 
today's rulemaking we are simply clarifying that any implementation 
plan revisions that are submitted to fulfill these additional Clean Air 
Act requirements are considered control strategy SIPs for conformity 
purposes. We are also clarifying that any SIP that is established to 
demonstrate reasonable further progress and/or attainment should be 
considered a control strategy SIP. This definition would include any 
progress or attainment SIP that is submitted for existing and future 
criteria pollutants and standards that are subject to the conformity 
regulation.
    Similarly, EPA is expanding the current definition of milestone in 
Sec.  93.101 to more adequately reflect EPA's original intent and 
implementation of this term. The current conformity rule defines 
milestone as having the meaning given in sections 182(g)(1) and 189(c) 
of the Clean Air Act. The rule also states that a milestone consists of 
an emissions level and the date on which it is required to be achieved.
    EPA has historically interpreted the conformity rule's definition 
of milestone to mean any year for which the Clean Air Act requires a 
demonstration of reasonable further progress towards attainment. Our 
interpretation covers all nonattainment areas, including all 
classifications of ozone areas, that are required to submit reasonable 
further progress SIPs and motor vehicle emission budgets. In 
reevaluating the current milestone definition, however, EPA has 
concluded that the current rule could be misinterpreted to mean that 
only serious and above ozone areas and PM10 areas would need 
to consider budgets established for milestone years required by Clean 
Air Act sections 182(g)(1) and 189(c), respectively. This 
interpretation could lead to confusion over how certain reasonable 
further progress SIPs should apply for conformity purposes. For 
example, the current milestone definition does not specifically address 
reasonable further progress SIP and budget years established by 
moderate ozone areas per Clean Air Act section 182(b)(1). As a result, 
the rule could be considered unclear about how moderate ozone areas 
should consider these particular SIPs in conformity. To address this 
ambiguity in the rule, we are proposing to expand our current 
definition of milestone so that it will include any year for which a 
motor vehicle emissions budget has been established to satisfy Clean 
Air Act requirements for demonstrating reasonable further progress. 
This definition would include all years in the applicable SIP for which 
emission targets showing progress towards attainment are established in 
any nonattainment area.
    EPA believes that neither of these proposed clarifications would 
have a practical impact on the current conformity process. The Clean 
Air Act and conformity rule require transportation activities to 
conform to the applicable SIP and motor vehicle emissions budgets prior 
to receiving funding and approval. Therefore, any adequate or approved 
budgets, including those that demonstrate reasonable further progress, 
that are available at the time a conformity determination is made must 
be included in that determination.
    Furthermore, it is EPA's understanding that conformity 
practitioners have historically been implementing the current rule's 
definitions as described above. For example, PM10 areas that 
have submitted 5% plans to satisfy Clean Air Act section 189(d) have 
used the motor vehicle emissions budgets established in these SIPs for 
conformity purposes and should continue to do so. Likewise, moderate 
ozone areas with reasonable further progress SIPs and budgets have 
historically used these budgets in conformity determinations. 
Therefore, the proposed clarifications to the rule's definitions for 
control strategy SIP revision and milestone should not impose any new 
requirements on nonattainment and maintenance areas; these rule 
revisions would simply clarify our original intent and current 
implementation of the existing conformity rule.

B. Areas With Insignificant Motor Vehicle Emissions

    EPA is proposing two changes to incorporate our existing 
insignificance policy in the conformity rule. First, we are proposing 
to add Sec.  93.109(k) for nonattainment and maintenance areas for 
which EPA makes a finding that the SIP's motor vehicle emissions for a 
pollutant or precursor for a given standard are an insignificant 
contributor to the area's air quality problem. The proposal would waive 
the regional emissions analysis requirements in Sec. Sec.  93.118 and 
93.119 for an insignificant pollutant or precursor in these areas upon 
the effective date of EPA's adequacy finding or approval of such a SIP. 
In addition, this proposal would waive the hot-spot requirements in 
Sec. Sec.  93.116 and 93.123 in CO and PM10 areas, if EPA 
determines that the SIP demonstrates that hot-spot emissions are also 
insignificant. The proposed Sec.  93.109(k) would also establish the 
minimum criteria that are necessary to demonstrate that motor vehicle 
emissions are insignificant as described below.
    Under this proposal and the existing policy, an area with 
insignificant motor vehicle emissions for a pollutant or precursor for 
a given standard would still be required to make a conformity 
determination that satisfies other relevant requirements including: SIP 
TCM implementation, interagency and public consultation, hot-spot 
requirements including the use of latest planning assumptions and 
emissions models in CO and PM10 areas (if EPA has not made a 
finding that such emissions are also insignificant), and compliance 
with SIP control measures in PM10 and PM2.5 
areas. Areas would also need to satisfy the regional emissions analysis 
requirements in Sec. Sec.  93.118 and/or 93.119 for pollutants

[[Page 62716]]

or precursors for which EPA has not made a finding of insignificance.
    Second, EPA is proposing a new Sec.  93.121(c) to address the 
conformity requirements for regionally significant non-federal projects 
in areas with insignificant motor vehicle emissions. The current rule's 
Sec.  93.121(a) and (b) require that the emissions impacts of such 
projects be considered prior to project approval. However, a regional 
analysis would not be required for a pollutant or precursor for a given 
standard that EPA has found insignificant. Consistent with proposed 
Sec.  93.109(k) for federal projects, this proposal would not require a 
regional emissions analysis per Sec. Sec.  93.118 and/or 93.119 for an 
insignificant pollutant or precursor for new regionally significant 
non-federal projects. However, the requirements in either Sec.  
93.121(a) or (b) would be required for any remaining pollutants or 
precursors for a given standard that are still considered significant 
(i.e., EPA has not determined such remaining pollutants or precursors 
to be insignificant). Therefore, Sec.  93.121(c) is proposed to allow 
non-federal project approvals in the limited cases of an EPA finding of 
insignificant emissions.
    Since EPA promulgated the original conformity rule (November 24, 
1993, 58 FR 62188), we have not required areas with insignificant motor 
vehicle emissions to conduct a regional emissions analysis for a 
pollutant or precursor that EPA has determined is insignificant to an 
area's air quality problem. In the preamble to the 1993 rule we 
explained that if a control strategy SIP demonstrates ``that motor 
vehicle emissions (including exhaust, evaporative and re-entrained road 
dust emissions) are insignificant and reductions are not necessary for 
attainment, the conformity determination is not required to satisfy the 
criteria for regional emissions analysis of that pollutant. If the 
control strategy SIP demonstrates that motor vehicle emissions of a 
precursor are insignificant and reductions are not necessary for 
attainment, the conformity determination is not required to satisfy the 
criteria for a regional emissions analysis of the precursor'' (58 FR 
62194).
    In the proposal to the 1997 rule (July 9, 1996, 61 FR 36118), we 
provided additional guidance to areas on what is necessary to 
demonstrate that motor vehicle emissions are insignificant contributors 
to an area's air quality problem. Specifically, the 1996 proposal 
states: ``the SIP would have to demonstrate that it would be 
unreasonable to expect that such an area would experience enough motor 
vehicle growth for a violation to occur. Such a demonstration would 
have to be based on a number of factors, including the percentage of 
the inventory comprised by motor vehicle-related emissions currently 
and in the future, how close the monitoring data is to the standard, 
the absence of SIP motor vehicle control measures, historical trends in 
growth of motor vehicle emissions and VMT, and projections of motor 
vehicle emissions and VMT.'' EPA's existing policy and guidance for 
insignificance serves as the basis for today's proposal and would apply 
when determining whether regional or hot-spot emissions are 
insignificant, and we are proposing to incorporate these criteria into 
the conformity rule.
    The proposed Sec.  93.109(k) is also consistent with other existing 
and proposed provisions of the rule in Sec. Sec.  93.102 and 93.119 
that address insignificance of pollutants and precursors before and 
after a SIP is submitted. See Sections VIII. and IX. for proposals for 
when PM2.5 precursors and re-entrained road dust would be 
considered significant for PM2.5 analyses.
    The July 1996 conformity proposal also indicates that EPA would 
conduct an adequacy review of initial SIPs that claim that motor 
vehicle emissions are insignificant. The adequacy review process would 
provide the public with an opportunity to comment on the adequacy of 
these SIPs and on whether or not the insignificance criteria have been 
met. EPA's adequacy finding for such SIPs would signify that we agree 
that the area has satisfactorily demonstrated insignificance based on 
the list of factors described above from the July 1996 proposal. EPA 
will determine significance of regional and hot-spot motor vehicle 
emissions in a given area on a case-by-case basis, and we will consider 
the impact of individual precursors, as well as the overall impact of 
all motor vehicle emissions in our insignificance finding. For more 
information on EPA's adequacy review of SIPs that claim insignificant 
motor vehicle emissions, see the preamble to the June 30, 2003 
conformity proposal that addresses the March 2, 1999 conformity court 
decision (68 FR 38983).
    Section 93.105(b) describes when the interagency consultation 
process is used in SIP development. The interagency consultation 
process can be used to consider the insignificance criteria reflected 
in today's proposed Sec.  93.109(k), and any other relevant local 
information. If the interagency consultation group for an area agrees 
that regional and/or hot-spot motor vehicle emissions are 
insignificant, such a finding should be clearly stated and well 
supported in a SIP that is subsequently submitted to EPA for adequacy 
review and/or approval.
    EPA developed the insignificance policy to provide flexibility for 
areas where motor vehicle emissions had little to no impact on an 
area's air quality problem. We believe that requiring these areas to 
perform a regional emissions analysis is not necessary to meet Clean 
Air Act section 176(c) requirements that transportation actions not 
worsen air quality, since the overall contribution of motor vehicle 
emissions in these areas is small and any significant change in such 
emissions over time would be unlikely. In addition, regional analyses 
may drain limited State and local resources from targeting the most 
important sources of air pollution in these areas. To date, 
approximately a dozen areas have taken advantage of the insignificance 
policy, consisting mainly of PM10 areas with air quality 
problems caused primarily by stationary or area sources. This current 
universe of areas has not changed significantly since 1993, and we do 
not anticipate the number of areas that could demonstrate 
insignificance of motor vehicle emissions to substantially increase in 
the future. Therefore, the proposal would waive regional emissions 
analyses in these areas without compromising air quality, since state 
and local resources could then be directed toward reducing emissions 
from those sources that contribute the most to an area's air quality 
problem.

C. Limited Maintenance Plans

    EPA currently has limited maintenance plan policies for the 1-hour 
ozone, CO, and PM10 standards. If a nonattainment area 
attains one of these standards and requests to be redesignated, it can 
choose to submit a more streamlined maintenance plan provided certain 
criteria are met. Although the three limited maintenance plan policies 
vary slightly, in general, an area would have to provide air quality 
data that shows with certainty that the area is attaining the standard 
and assurance that future violations of that standard are unlikely. In 
addition, an area would need to demonstrate that only limited growth in 
transportation emissions in the area is expected.
    EPA is proposing three rule revisions that would make the 
conformity rule consistent with EPA's existing limited maintenance plan 
policies. Today's proposal would also allow for any future limited 
maintenance plan

[[Page 62717]]

policies for other standards to be considered in the conformity 
process.
    First, EPA is proposing in Sec.  93.101 to add a basic definition 
for ``limited maintenance plan.'' Second, we are proposing a new 
paragraph Sec.  93.109(j) that states that a regional emissions 
analysis is not required to satisfy Sec. Sec.  93.118 and/or 93.119 in 
areas that have an adequate or approved limited maintenance plan for a 
given pollutant and standard. However, a conformity determination that 
meets other applicable criteria, including the hot-spot requirements 
for projects in CO and PM10 nonattainment and maintenance areas, 
interagency and public consultation, and SIP TCM implementation, would 
still be required in these areas. A regional analysis would also be 
required for any other pollutants or standards that otherwise apply. 
The proposed Sec.  93.109(j) would require a limited maintenance plan 
to demonstrate that it would be unreasonable to expect that an area 
would experience enough motor vehicle emissions growth to cause a 
violation. The interagency consultation process should be used to 
discuss the development of a limited maintenance plan (40 CFR 
93.105(b)).
    Third, as discussed above, EPA is proposing a new Sec.  93.121(c) 
to clarify when funding and approval for new regionally significant 
non-federal projects would be granted. Consistent with our proposed 
Sec.  93.109(j) for federal projects in areas with limited maintenance 
plans, this proposal would not require a regional emissions analysis 
per Sec. Sec.  93.118 and/or 93.119 to be satisfied for regionally 
significant non-federal projects for the pollutant and standard that is 
addressed by the limited maintenance plan. However, the requirements in 
either Sec.  93.121(a) or (b) would be required to be satisfied for any 
remaining pollutant or standard that apply in an area that are not 
addressed by the limited maintenance plan.
    EPA believes that violations of a pollutant and standard due to 
unexpected growth would be highly unlikely in limited maintenance plan 
areas. Furthermore, EPA considers it a reasonable assumption that motor 
vehicle emissions in a limited maintenance plan area could increase to 
any realistic level during the maintenance period without causing or 
contributing to a violation of the standard. As a result, limited 
maintenance plans are treated as essentially not constraining for the 
length of the maintenance period, and the Clean Air Act requirements to 
not worsen air quality are met without a regional conformity analysis. 
While this policy does not exempt an area from the need to affirm 
conformity, it does eliminate the basis for the regional emission 
analysis since EPA would be concluding through our adequacy review or 
approval of the limited maintenance plan that limits on motor vehicle 
emissions during the maintenance period are unnecessary.
    The proposed revisions to Sec. Sec.  93.101, 93.109 and 93.121 
would not have a practical impact on how conformity is demonstrated in 
areas with applicable limited maintenance plans, as EPA is simply 
proposing to incorporate into the conformity rule our existing policies 
for these areas. The purpose of these proposed revisions is to assist 
limited maintenance plan areas in their efforts to implement 
conformity. These revisions would in no way impose additional 
requirements for limited maintenance plan areas, nor would it eliminate 
any existing requirements that could compromise air quality.
    For more information on transportation conformity and limited 
maintenance plans, see the preamble to the July 9, 1996 proposed 
conformity rule (61 FR 36118) and EPA's existing limited maintenance 
plan policies. For a discussion on EPA's adequacy review of limited 
maintenance plans, see the preamble to the June 30, 2003 proposal (68 
FR 38974).

D. Grace Period for Transportation Modeling and Plan Content 
Requirements in Certain Ozone and CO Areas

    EPA is proposing three changes to the conformity rule's provisions 
for when more rigorous transportation modeling and plan content 
requirements apply in certain ozone and CO areas. First, we are 
proposing a two-year grace period before the more advanced 
transportation modeling requirements in Sec.  93.122(b) are required in 
the following types of areas: (1) Ozone and CO areas that are already 
classified as serious or above in which the urbanized area population 
increases to over 200,000, and (2) moderate ozone and CO areas that 
have an urbanized area population over 200,000 and are reclassified to 
serious (for ozone and CO) or severe (for ozone only). Section 
93.122(b) of the current rule requires more advanced transportation 
network modeling requirements only in serious and above ozone and CO 
areas with urbanized populations over 200,000.
    Second, EPA is proposing to expand the types of areas covered by 
the current rule's grace period for transportation plan content 
requirements. Section 93.106(b) currently includes a two-year grace 
period before the more specific transportation plan requirements in 
Sec.  93.106(a) apply in moderate ozone and CO areas that are 
reclassified to serious and have urbanized populations over 200,000. 
The proposal would provide that same flexibility to: (1) Serious and 
severe ozone areas and serious CO areas in which the urbanized area 
population increases to over 200,000, and (2) moderate ozone areas that 
are reclassified to severe.
    Third, we are clarifying in both Sec. Sec.  93.106 and 93.122 that 
the two-year grace periods would begin upon either: (1) The official 
notice by the Census Bureau that the urbanized area population is over 
200,000, or (2) the effective date of EPA's action that reclassifies a 
larger metropolitan moderate ozone or CO area to serious (ozone and CO) 
or severe (ozone only). An example of an official notice by the Census 
Bureau would be an announcement in the Federal Register that the 
urbanized population in a metropolitan area has increased to over 
200,000.
    EPA is making the above changes to provide flexibility as 
originally intended. In the proposal to the 1993 conformity rule, EPA 
explained that the purpose of the two-year grace period in applying 
these more specific transportation plan content requirements in 
moderate areas that are bumped-up to a serious classification is to 
``allow these areas time to specify their networks and perform the 
other research and data collection activities necessary to develop 
network models and specific plans'' (January 11, 1993, 58 FR 3776). 
Adding the two-year grace period to Sec.  93.122 provides this extra 
time. Furthermore, specific transportation plans are required in higher 
classification ozone and CO areas in Sec.  93.106(a) to allow for more 
sophisticated modeling in such areas in Sec.  93.122(b). For example, 
Sec.  93.106(a) requires the most recent demographic and land-use 
information and a detailed description of the transit and highway 
system for each required transportation plan horizon year. Such details 
would be part of a more advanced analysis under Sec.  93.122(b).
    For the reasons stated in the 1993 rule, EPA originally intended 
Sec. Sec.  93.106 and 93.122 of the conformity rule to work together. 
Providing a two-year grace period for the more specific transportation 
plan requirements in Sec.  93.106(a), without providing such a grace 
period for the more advanced modeling requirements in Sec.  93.122(b) 
does not achieve the flexibility that was intended for these areas.
    In addition, EPA believes that the two-year grace periods should 
also

[[Page 62718]]

apply in ozone and CO areas that are already classified serious or 
above, but that are currently not required to meet the more rigorous 
plan and modeling requirements because their urbanized area population 
is lower than 200,000. If the urbanized area population in such an area 
increases to over 200,000, EPA believes it is reasonable that such an 
area would also need additional time to specify its networks and gather 
additional data to develop a more specific plan and conduct more 
advanced transportation modeling.
    The proposed clarification to the existing Sec.  93.106(b) 
provision, as well as the proposed Sec.  93.122(c), would also provide 
flexibility in limited cases where a moderate ozone area is 
reclassified to severe. For example, when moderate ozone areas with an 
urbanized population greater than 200,000 fail to attain the standard 
by either the moderate or serious ozone attainment dates specified in 
the Clean Air Act, EPA could reclassify these areas to severe. Today's 
proposal would clarify how the grace period would be implemented in 
such limited cases. This particular proposal would not be relevant to 
moderate CO areas, as these areas can only be reclassified to serious 
if they fail to attain by their specified attainment date. The Clean 
Air Act does not provide for a severe CO classification.
    Finally, we should note that today's proposals would not make any 
changes to the existing transportation plan content and modeling 
requirements. The proposal would simply clarify when these requirements 
begin to apply when circumstances change in certain areas.

E. Minor Clarification to the List of PM10 Precursors

    We are proposing minor clarifications to Sec. Sec.  
93.102(b)(2)(iii) and 93.119(f)(5) of the conformity rule. Under the 
proposed Sec.  93.102(b)(2)(iii), only VOC and NOX would be 
identified as PM10 precursors, and PM10 would be 
deleted from the list of PM10 precursors in this paragraph. 
We are proposing this clarification because Sec.  93.102(b)(1) already 
requires that direct PM10 emissions be addressed in 
conformity analyses in PM10 nonattainment and maintenance 
areas. Therefore, inclusion of direct PM10 as a 
PM10 precursor in Sec.  93.102(b)(2)(iii) is duplicative.
    The proposed changes to Sec.  93.119(f)(5) would provide 
consistency with other pollutants and precursors discussed in this 
paragraph. Neither of these proposals would affect conformity 
determinations in PM10 nonattainment and maintenance areas.

F. Clarification of Requirements for Non-federal Projects in Isolated 
Rural Areas

    EPA is proposing a minor clarification to Sec.  93.121(b)(1) of the 
conformity rule that addresses the conformity requirements for non-
federal projects in isolated rural nonattainment and maintenance areas. 
Specifically, the proposal would require a regionally significant non-
federal project to be included in the regional emissions analysis of 
the most recent conformity determination ``that reflects'' the portion 
of the statewide transportation plan and STIP which includes projects 
planned for the isolated rural nonattainment or maintenance area.
    Today's proposed revision to Sec.  93.121(b)(1) is intended to 
clarify that conformity determinations in isolated rural nonattainment 
and maintenance areas should not be ``for'' the statewide 
transportation plan or STIP, as written in the current rule. In the 
proposal for the original 1993 conformity rule, we explain that ``STIPs 
are not TIPs as the latter term is meant in Clean Air Act section 
176(c), and that conformity therefore does not apply to [STIPs] 
directly'' (January 11, 1993, 58 FR 62206). However, isolated rural 
areas do not develop metropolitan transportation plans and TIPs per 
DOT's planning regulations. Instead, conformity determinations in 
isolated rural nonattainment and maintenance areas should include those 
existing and planned projects that are within the area and that are 
reflected in the statewide transportation plan and STIP, including 
regionally significant non-federal projects. This proposed change 
simply clarifies the conformity requirements for isolated rural 
nonattainment and maintenance areas and should not have a practical 
impact on how conformity is demonstrated in these areas.

G. Use of Adequate and Approved Budgets in Conformity

    EPA is clarifying in Sec.  93.109 for each criteria pollutant and 
standard covered by the conformity rule that the budget test must be 
satisfied as required by Sec.  93.118 for conformity determinations 
made on or after one of the following:
    [sbull] The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted SIP is adequate,
    [sbull] The publication date of EPA's approval of such a budget in 
the Federal Register, or
    [sbull] The effective date of EPA's approval of such a budget in 
the Federal Register, if the approval is completed through direct final 
rulemaking.
    Under this proposal, the budget would be used the first time one of 
these three EPA actions occur. In EPA's June 30, 2003 proposal that 
would implement the March 2, 1999 conformity court decision, we 
proposed to only require the budget test after the effective date of 
EPA's finding that a control strategy SIP or maintenance plan 
submission is adequate. Our June 2003 proposal for Sec.  93.109 was 
incomplete.
    When an area submits an attainment demonstration, rate-of-progress 
plan or maintenance plan with motor vehicle emissions budgets, EPA will 
generally review that SIP for adequacy so that the budgets can be used 
prior to EPA's approval of the SIP. However, there have been limited 
and unique cases where EPA has not conducted the adequacy review 
process prior to the approval of the SIP. Rather, EPA may simply 
approve such SIPs through a separate proposal and final rule or through 
direct final rulemaking. Today's proposal would simply clarify that in 
these limited cases the budget test would be required upon the 
publication date of EPA's final approval of the SIP and motor vehicle 
emissions budgets in the Federal Register, or the effective date of 
EPA's direct final rulemaking, whichever applies in a given situation.
    EPA believes that this proposed clarification would have no 
practical impact on how the budget test is implemented when new budgets 
become available for conformity purposes. The Clean Air Act section 
176(c) requires that transportation activities conform to the motor 
vehicle emissions level established in the approved SIP. Therefore, 
once a SIP is approved, its budgets must be used in conformity under 
the statute. In addition, since the March 2, 1999 court decision, areas 
have incorporated new budgets from submitted SIPs into the 
transportation planning and conformity processes as soon as they are 
deemed appropriate for conformity--either through EPA's adequacy or 
approval processes.
    We should also note that this clarification to Sec.  93.109 as 
proposed in the June 30, 2003 conformity proposal, is consistent with 
the March 1999 court decision and EPA's May 14, 1999 guidance 
implementing that decision. Under this proposal, submitted SIPs and 
motor vehicle emissions budgets would be used in conformity 
determinations only after EPA has formally found such budgets to be 
consistent with an area's plan for achieving clean air. For more 
information on EPA's adequacy process and the types of submitted SIPs 
that EPA will review for adequacy, see EPA's May 14, 1999 guidance 
implementing the March 1999 court decision and the

[[Page 62719]]

preamble to the June 30, 2003 proposal (68 FR 38974).

XV. How Does Today's Proposal Affect Conformity SIPs?

    Clean Air Act section 176(c)(4)(C) currently requires states to 
submit revisions to their SIPs to reflect all of the federal criteria 
and procedures for determining conformity. States can choose to develop 
conformity SIPs as a memorandum of understanding (MOU), memorandum of 
agreement (MOA), or state rule. However, a state must have the 
authority to make an MOU or MOA enforceable as a matter of state law, 
if such mechanisms are used.
    Section 51.390(b) of the conformity rule specifies that after EPA 
approves any conformity SIP revision, the federal conformity rule no 
longer governs conformity determinations (for the sections of the 
federal conformity rule that are covered by the approved conformity 
SIP). Areas without approved conformity SIPs will be able to use 
immediately any conformity amendments that are finalized in the future 
as a result of today's proposed action.
    In contrast, EPA has already approved conformity SIPs in some areas 
that include sections from previous conformity rulemakings. In general, 
amendments to a section of the federal rule other than those compelled 
by a court decision become effective in states with approved conformity 
SIPs only when the State includes the amended section in a conformity 
SIP revision and EPA approves that SIP revision. EPA will continue to 
work with states to approve such revisions as expeditiously as possible 
through flexible administrative techniques, such as parallel processing 
or direct final rulemaking.
    There are, however, aspects of today's proposal that should not 
already be in any approved conformity SIPs, since new provisions are 
being proposed to implement the 8-hour ozone and PM2.5 
standards. For these new provisions, all 8-hour ozone and 
PM2.5 areas will be able to use such amendments upon the 
effective date of a final rule based on this proposal. When a final 
rule is issued, EPA will provide guidance on when sections of the rule 
can be used in the conformity process in areas with approved conformity 
SIPs.

XVI. Public Hearing

    Anyone who wants to present testimony about this proposal at the 
public hearing (see DATES) should, if possible, notify the contact 
persons listed in the FOR FURTHER INFORMATION CONTACT section of this 
proposal at least seven days prior to the day of the hearing. The 
contact person(s) should be given an estimate of the time required for 
the presentation of testimony and notification of any need for audio/
visual equipment. A sign-up sheet will be available at the registration 
table the morning of the hearing for scheduling those who have not 
notified the EPA contact(s) earlier. This testimony will be scheduled 
on a first-come, first-serve basis to follow the previously scheduled 
testimony.
    EPA requests that approximately 50 copies of the statement or 
material to be presented be brought to the hearing for distribution to 
the audience. In addition, EPA would find it helpful to receive an 
advance copy of any statement or material to be presented at the 
hearing at least one week before the scheduled hearing date. Such 
advance copies would give EPA staff adequate time to review the 
materials before the hearing. Advance copies should be submitted to the 
EPA contact person(s) listed in this proposal.
    The official records of the hearing will be kept open until the 
close of the comment period to allow submission of rebuttal and 
supplementary testimony. All such submissions should be directed to the 
Air Docket I.D. No. OAR-2003-0049. See Section I.C. of this proposal 
for more information on how to submit comments to the docket. The 
hearing will be conducted informally, and technical rules of evidence 
will not apply. A written transcript of the hearing will be placed in 
the docket for review. Anyone who desires to purchase a copy of the 
transcript should make individual arrangements with the court reporter 
recording the proceeding.

XVII. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

    Under Executive Order 12866, (58 FR 51735; October 4, 1993) the 
Agency must determine whether the regulatory action is ``significant'' 
and therefore subject to OMB review and the requirements of the 
Executive Order. The Order defines significant ``regulatory action'' as 
one that is likely to result in a rule that may:
    (1) Have an annual effect on the economy of $100 million or more, 
or otherwise adversely affect in a material way the economy, a sector 
of the economy, productivity, competition, jobs, the environment, 
public health or safety, or State, local, or tribal governments or 
communities;
    (2) create a serious inconsistency or otherwise interfere with an 
action taken or planned by another agency;
    (3) materially alter the budgetary impact of entitlements, grants, 
user fees, or loan programs or the rights and obligations of recipients 
thereof;
    (4) raise novel legal or policy issues arising out of legal 
mandates, the President's priorities, or the principles set forth in 
the Executive Order.
    It has been determined that this proposed rule is a ``significant 
regulatory action'' because this action raises novel legal or policy 
issues arising out of legal mandates and the principles set forth in 
the Executive Order. As such, this action was submitted to OMB for 
review. Changes made in response to OMB suggestions or recommendations 
will be documented in the public record.

B. Paperwork Reduction Act

    The information collection requirements in this proposed rule will 
be submitted for approval to the Office of Management and Budget (OMB) 
under the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. (ICR 
2103.01). The information collection requirements are not enforceable 
until OMB approves them.
    Transportation conformity determinations are required under Clean 
Air Act section 176(c) (42 U.S.C. 7506(c)) to ensure that federally 
supported highway and transit project activities are consistent with 
(``conform to'') the purpose of the SIP. Conformity to the purpose of 
the SIP means that transportation activities will not cause new air 
quality violations, worsen existing violations, or delay timely 
attainment of the relevant air quality standards. Transportation 
conformity applies under EPA's conformity regulations at 40 CFR 51.390 
and 40 CFR part 93 to areas that are designated nonattainment and those 
redesignated to attainment after 1990 (``maintenance areas'' with plans 
developed under Clean Air Act section 175A) for transportation-source 
criteria pollutants. The Clean Air Act gives EPA the statutory 
authority to establish the criteria and procedures for determining 
whether transportation activities conform to the SIP.
    EPA estimates that this rulemaking will place additional burden on 
those areas that are designated nonattainment for the first time and 
have no prior experience with the conformity process. For these 
completely ``new'' areas there will be burden associated with rule 
familiarization, transportation and emissions modeling and interagency 
consultation. New metropolitan

[[Page 62720]]

nonattainment areas will be required to demonstrate conformity of their 
transportation plans every three years. In addition, DOT's planning 
regulations require TIP updates every two years, and consequently, a 
TIP conformity determination will be required every two years. Based on 
preliminary air quality data and State recommendations for new 
nonattainment areas, we estimate that approximately 40 areas will be 
designated nonattainment for the first time under the 8-hour ozone and 
PM2.5 standards. We estimate that the total annual burden 
per respondent for transportation conformity activities is 275 hours at 
a total annual cost per respondent of $6750.00.
    The information collection requirements of EPA's current 
transportation conformity rule are covered under the DOT information 
collection request (ICR) entitled, ``Metropolitan and Statewide 
Transportation Planning,'' with the OMB Control Number 2132-0529. 
Today's total burden for new areas is based on DOT's ICR for developing 
transportation plans and TIPs in nonattainment and maintenance areas, 
and should be viewed as a cursory estimate. Today's estimate only 
includes the incremental burden associated with making conformity 
determinations for the new standards; it does not address the 
development of transportation plans and TIPs or motor vehicle emissions 
budgets, since these documents are developed to meet other 
requirements. The total annual burden also assumes that all new areas 
will be metropolitan areas that develop transportation plans and TIPs. 
Accounting for newly designated isolated rural nonattainment areas may 
reduce the total burden for new areas, as isolated rural areas are not 
required to demonstrate conformity as often as metropolitan areas. In 
addition, this estimate of new burden assumes that plan and TIP 
conformity determinations are developed separately. However, the 
regional emissions analysis requirements in the conformity regulation 
are the same for plans and TIPs, and many areas rely on the same 
regional emissions analysis and conformity determination when plan and 
TIP updates are done concurrently. EPA plans to further examine this 
burden estimate for new areas designated under the 8-hour ozone and 
PM2.5 standards, along with any incremental burdens for 
existing nonattainment and maintenance areas that have previous 
conformity experience, in our subsequent ICR for this rulemaking.
    Burden means the total time, effort, or financial resources 
expended by persons to generate, maintain, retain, or disclose or 
provide information to or for a Federal agency. This includes the time 
needed to review instructions; develop, acquire, install, and utilize 
technology and systems for the purposes of collecting, validating, and 
verifying information, processing and maintaining information, and 
disclosing and providing information; adjust the existing ways to 
comply with any previously applicable instructions and requirements; 
train personnel to be able to respond to a collection of information; 
search data sources; complete and review the collection of information; 
and transmit or otherwise disclose the information.
    An agency may not conduct or sponsor, and a person is not required 
to respond to a collection of information unless it displays a 
currently valid OMB control number. The OMB control numbers for EPA's 
regulations in 40 CFR are listed in 40 CFR part 9.
    To comment on the Agency's need for this information, the accuracy 
of the provided burden estimates, and any suggested methods for 
minimizing respondent burden, including the use of automated collection 
techniques, EPA has established a public docket for this rulemaking, 
which will include the ICR, under Docket ID number OAR-2003-0049. EPA 
is seeking comment on the general description of this proposal's 
information collection. EPA intends, in the near future, to develop and 
submit to OMB an ICR that includes a more detailed estimate of the 
incremental burden of this rulemaking. The public will be provided a 
separate comment period to comment on the ICR once it is submitted to 
OMB. Submit any comments related to the collection of information and 
subsequent ICR for this proposed rule to EPA and OMB. See the ADDRESSES 
section of this notice for where to submit comments to EPA. Send 
comments to OMB at the Office of Information and Regulatory Affairs, 
Office of Management and Budget, 725 17th Street, NW., Washington, DC 
20503, Attention: Desk Office for EPA. The final rule will respond to 
any OMB or public comments on the information collection requirements 
contained in this proposal and subsequent ICR.

C. Regulatory Flexibility Act

    The Regulatory Flexibility Act, as amended by the Small Business 
Regulatory Enforcement Fairness Act of 1996, requires the Agency to 
conduct a regulatory flexibility analysis of any significant impact a 
rule will have on a substantial number of small entities. Small 
entities include small businesses, small not-for-profit organizations 
and small government jurisdictions.
    EPA has determined that today's proposal will not have a 
significant impact on a substantial number of small entities. This 
regulation directly affects Federal agencies and metropolitan planning 
organizations that, by definition, are designated under Federal 
transportation laws only for metropolitan areas with a population of at 
least 50,000. These organizations do not constitute small entities 
within the meaning of the Regulatory Flexibility Act. The Regulatory 
Flexibility Act defines a ``small governmental jurisdiction'' as the 
government of a city, county, town, school district or special district 
with a population of less than 50,000.
    Therefore, as required under section 605 of the Regulatory 
Flexibility Act, 5 U.S.C. 601 et seq., I certify that this proposed 
rule will not have a significant economic impact on a substantial 
number of small entities.

D. Unfunded Mandates Reform Act

    Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public 
Law 104-4, establishes requirements for Federal agencies to assess the 
effects of their regulatory actions on State, local, and tribal 
governments and the private sector. Under section 202 of the UMRA, EPA 
generally must prepare a written statement, including a cost-benefit 
analysis, for proposed and final rules with ``Federal mandates'' that 
may result in expenditures to State, local, and tribal governments, in 
the aggregate, or to the private sector, of $100 million or more in any 
one year. Before promulgating an EPA rule for which a written statement 
is needed, section 205 of the UMRA generally requires EPA to identify 
and consider a reasonable number of regulatory alternatives and adopt 
the least costly, most cost-effective or least burdensome alternative 
that achieves the objectives of the rule. The provisions of section 205 
do not apply when they are inconsistent with applicable law. Moreover, 
section 205 allows EPA to adopt an alternative other than the least 
costly, most cost-effective or least burdensome alternative if the 
Administrator publishes with the final rule an explanation why that 
alternative was not adopted. Before EPA establishes any regulatory 
requirements that may significantly or uniquely affect small 
governments, including tribal governments, it must have developed under 
section 203 of the UMRA a small government agency plan. The plan must 
provide for notifying potentially affected small governments, enabling 
officials of affected small governments

[[Page 62721]]

to have meaningful and timely input in the development of EPA 
regulatory proposals with significant Federal intergovernmental 
mandates, and informing, educating, and advising small governments on 
compliance with the regulatory requirements.
    EPA has determined that this proposed rule itself does not contain 
a Federal mandate that may result in expenditures of $100 million or 
more for State, local, and tribal governments, in the aggregate, or the 
private sector in any one year. The primary purpose of this proposed 
rule is to amend the existing Federal conformity regulations to cover 
areas newly designated nonattainment under the recently promulgated 8-
hour ozone and fine particulate (PM2.5) ambient air quality 
standards. Clean Air Act section 176(c)(5) requires the applicability 
of conformity to such areas as a matter of law one year after 
nonattainment designations. Thus, although this rule explains how 
conformity should be conducted, it merely implements already 
established law that imposes conformity requirements and does not 
itself impose requirements that may result in expenditures of $100 
million or more in any year. Additional rule amendments also addressed 
in this proposal simply serve to improve the conformity regulation by 
implementing the rule in a more practicable manner and/or to clarify 
conformity requirements that already exist. None of these proposed 
amendments impose any additional burdens beyond that already imposed by 
applicable Federal law; thus, today's proposed rule is not subject to 
the requirements of sections 202 and 205 of the UMRA and EPA has not 
prepared a statement with respect to budgetary impacts.

E. Executive Order 13132: Federalism

    Executive Order 13132, Federalism (64 FR 43255, August 10, 1999), 
revokes and replaces Executive Orders 12612 (Federalism) and 12875 
(Enhancing the Intergovernmental Partnership). Executive Order 13132 
requires EPA to develop an accountable process to ensure ``meaningful 
and timely input by State and local officials in the development of 
regulatory policies that have federalism implications.'' ``Policies 
that have federalism implications'' is defined in the Executive Order 
to include regulations that have ``substantial direct effects on the 
States, on the relationship between the national government and the 
States, or on the distribution of power and responsibilities among the 
various levels of government.'' Under Executive Order 13132, EPA may 
not issue a regulation that has federalism implications, that imposes 
substantial direct compliance costs, and that is not required by 
statute, unless the Federal government provides the funds necessary to 
pay the direct compliance costs incurred by State and local 
governments, or EPA consults with State and local officials early in 
the process of developing the regulation. EPA also may not issue a 
regulation that has federalism implications and that preempts State law 
unless the Agency consults with State and local officials early in the 
process of developing the proposed regulation.
    If EPA complies by consulting, Executive Order 13132 requires EPA 
to provide to the Office of Management and Budget (OMB), in a 
separately identified section of the preamble to the rule, a federalism 
summary impact statement (FSIS). The FSIS must include a description of 
the extent of EPA's prior consultation with State and local officials, 
a summary of the nature of their concerns and the Agency's position 
supporting the need to issue the regulation, and a statement of the 
extent to which the concerns of State and local officials have been 
met. Also, when EPA transmits a draft rule with federalism implications 
to OMB for review pursuant to Executive Order 12866, EPA must include a 
certification from the Agency's Federalism Official stating that EPA 
has met the requirements of Executive Order 13132 in a meaningful and 
timely manner.
    This proposed rule, that amends a regulation that is required by 
statute, will not have substantial direct effects on the States, on the 
relationship between the national government and the States, or on the 
distribution of power and responsibilities among the various levels of 
government, as specified in Executive Order 13132. The Clean Air Act 
requires conformity to apply in certain nonattainment and maintenance 
areas as a matter of law, and this proposed rule merely establishes and 
revises procedures for transportation planning entities in subject 
areas to follow in meeting their existing statutory obligations. 
Similarly, other minor amendments included in today's proposal are the 
result of related administrative matters, or have been proposed simply 
to make the rule more workable and/or to clarify requirements that 
already exist under the current conformity regulation.
    In summary, this proposed rule is required primarily by the 
statutory requirements imposed by the Clean Air Act, and the proposed 
rule by itself will not have a substantial impact on States. Thus, the 
requirements of section 6 of the Executive Order do not apply to this 
proposed rule.

F. Executive Order 13175: Consultation and Coordination With Indian 
Tribal Governments

    Executive Order 13175: ``Consultation and Coordination with Indian 
Tribal Governments'' (65 FR 67249, November 6, 2000) requires EPA to 
develop an accountable process to ensure ``meaningful and timely input 
by tribal officials in the development of regulatory policies that have 
tribal implications.'' ``Policies that have tribal implications'' is 
defined in the Executive Order to include regulations that have 
``substantial direct effects on one or more Indian tribes, on the 
relationship between the Federal government and the Indian tribes, or 
on the distribution of power and responsibilities between the Federal 
government and Indian tribes.''
    Today's amendments to the conformity rule do not significantly or 
uniquely affect the communities of Indian tribal governments, as the 
Clean Air Act requires transportation conformity to apply in any area 
that is designated nonattainment or maintenance by EPA. Specifically, 
this proposed rule would incorporate into the conformity rule 
provisions addressing newly designated nonattainment areas subject to 
conformity requirements under the Act, as well as several other 
clarifications and improvements, that would not have substantial direct 
effects on tribal governments, on the relationship between the Federal 
government and Indian tribes, or on the distribution of power and 
responsibilities between the Federal government and Indian tribes, as 
specified in Executive Order 13175. Accordingly, the requirements of 
Executive Order 13175 are not applicable to this proposal.

G. Executive Order 13045: Protection of Children From Environmental 
Health and Safety Risks

    Executive Order 13045: ``Protection of Children from Environmental 
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997) applies 
to any rule that: (1) Is determined to be ``economically significant'' 
as defined under Executive Order 12866, and (2) concerns an 
environmental health or safety risk that EPA has reason to believe may 
have a disproportionate effect on children. If the regulatory action 
meets both criteria, the Agency must evaluate the environmental health 
or safety effects of the planned rule on children, and explain why the 
planned regulation is preferable to other potentially effective

[[Page 62722]]

and reasonably feasible alternatives considered by the Agency.
    This proposed rule is not subject to Executive Order 13045 because 
it is not economically significant within the meaning of Executive 
Order 12866 and does not involve the consideration of relative 
environmental health or safety risks.

H. Executive Order 13211: Actions That Significantly Affect Energy 
Supply, Distribution or Use

    This rule is not subject to Executive Order 13211, ``Action 
Concerning Regulations That Significantly Affect Energy Supply, 
Distribution, or Use'' (66 FR 28355; May 22, 2001) because it will not 
have a significant adverse effect on the supply, distribution, or use 
of energy. Further, we have determined that this proposed rule is not 
likely to have any significant adverse effects on energy supply.

I. National Technology Transfer and Advancement Act

    Section 12(d) of the National Technology Transfer and Advancement 
Act of 1995 (``NTTAA''), Public Law No. 104-113, section 12(d) (15 
U.S.C. 272 note) directs EPA to use voluntary consensus standards in 
its regulatory activities unless to do so would be inconsistent with 
applicable law or otherwise impractical. Voluntary consensus standards 
are technical standards (e.g., materials specifications, test methods, 
sampling procedures, and business practices) that are developed or 
adopted by voluntary consensus standards bodies. The NTTAA directs EPA 
to provide Congress, through OMB, explanations when the Agency decides 
not to use available and applicable voluntary consensus standards.
    This proposed rulemaking does not involve technical standards. 
Therefore, the use of voluntary consensus standards does not apply to 
this proposed rule.

List of Subjects in 40 CFR Part 93

    Environmental protection, Administrative practice and procedure, 
Air pollution control, Carbon monoxide, Intergovernmental relations, 
Nitrogen Dioxide, Ozone, Particulate matter, Transportation, Volatile 
organic compounds.

    Dated: October 22, 2003.
Marianne Lamont Horinko,
Acting Administrator.
    For the reasons set out in the preamble, 40 CFR part 93 is proposed 
to be amended as follows:

PART 93--[AMENDED]

    1. The authority citation for part 93 continues to read as follows:

    Authority: 42 U.S.C. 7401-7671q.

    2. Section 93.101 is amended by adding, in alphabetical order, new 
definitions for ``1-hour ozone NAAQS,'' ``8-hour ozone NAAQS'' and 
``Limited maintenance plan,'' and by revising definitions for ``Control 
strategy implementation plan revision'' and ``Milestone'' to read as 
follows:


Sec.  93.101  Definitions.

* * * * *
    1-hour ozone NAAQS means the 1-hour ozone national ambient air 
quality standard codified at 40 CFR 50.9.
* * * * *
    8-hour ozone NAAQS means the 8-hour ozone national ambient air 
quality standard codified at 40 CFR 50.10.
* * * * *
    Control strategy implementation plan revision is the implementation 
plan which contains specific strategies for controlling the emissions 
of and reducing ambient levels of pollutants in order to satisfy CAA 
requirements for demonstrations of reasonable further progress and 
attainment (including implementation plan revisions submitted to 
satisfy CAA sections 172(c), 182(b)(1), 182(c)(2)(A), 182(c)(2)(B), 
187(a)(7), 187(g), 189(a)(1)(B), 189(b)(1)(A), and 189(d); sections 
192(a) and 192(b), for nitrogen dioxide; and any other applicable CAA 
provision requiring a demonstration of reasonable further progress or 
attainment).
* * * * *
    Limited maintenance plan is a maintenance plan that EPA has 
determined meets EPA's limited maintenance plan policy criteria for a 
given NAAQS and pollutant. To qualify for a limited maintenance plan, 
for example, an area must have a design value that is below a given 
NAAQS, and it must be reasonable to expect that a NAAQS violation will 
not result from any level of future motor vehicle emissions growth.
* * * * *
    Milestone has the meaning given in CAA sections 182(g)(1) and 
189(c) for serious and above ozone nonattainment areas and 
PM10 nonattainment areas, respectively. For all other 
nonattainment areas, a milestone consists of an emissions level and the 
date on which that level is to be achieved as required by the 
applicable CAA provision for reasonable further progress towards 
attainment.
* * * * *
    3. Section 93.102 is amended by:
    a. Revising paragraphs (b)(1), (b)(2) introductory text and 
(b)(2)(iii);
    b. removing the word ``and'' at the end of paragraph (b)(2)(ii);
    c. adding paragraphs (b)(2)(iv) and (v);
    d. redesignating paragraph (b)(3) as paragraph (b)(4);
    e. adding a new paragraph (b)(3); and
    f. revising paragraph (d).
    The revisions and additions read as follows:


Sec.  93.102  Applicability.

* * * * *
    (b) * * *
    (1) The provisions of this subpart apply with respect to emissions 
of the following criteria pollutants: ozone, carbon monoxide (CO), 
nitrogen dioxide (NO2), particles with an aerodynamic 
diameter less than or equal to a nominal 10 micrometers 
(PM10); and particles with an aerodynamic diameter less than 
or equal to a nominal 2.5 micrometers (PM2.5).
    (2) The provisions of this subpart also apply with respect to 
emissions of the following precursor pollutants:
* * * * *
    (iii) VOC and/or NOX in PM10 areas if the EPA 
Regional Administrator or the director of the State air agency has made 
a finding that transportation-related emissions of one or both of these 
precursors within the nonattainment area are a significant contributor 
to the PM10 nonattainment problem and has so notified the 
MPO and DOT, or if the applicable implementation plan (or 
implementation plan submission) establishes an approved (or adequate) 
budget for such emissions as part of the reasonable further progress, 
attainment or maintenance strategy;
    Option 1 for paragraphs (b)(2)(iv) and (v):
    (iv) VOC and/or NOX in PM2.5 areas, unless 
the EPA Regional Administrator or the director of the State air agency 
has made a finding that transportation-related emissions of one or both 
of these precursors within the nonattainment area are not a significant 
contributor to the PM2.5 nonattainment problem and has so 
notified the MPO and DOT, or if the applicable implementation plan (or 
implementation plan submission) does not establish an approved (or 
adequate) budget for such emissions as part of the reasonable further 
progress, attainment or maintenance strategy; and
    (v) Oxides of sulfur (SOX) and/or ammonia 
(NH3) in PM2.5 areas if the EPA Regional 
Administrator or the director of the State air agency has made a 
finding that transportation-related emissions of one or both of these 
precursors within the nonattainment

[[Page 62723]]

area are a significant contributor to the PM2.5 
nonattainment problem and has so notified the MPO and DOT, or if the 
applicable implementation plan (or implementation plan submission) 
establishes an approved (or adequate) budget for such emissions as part 
of the reasonable further progress, attainment or maintenance strategy.
    Option 2 for paragraph (b)(2)(iv) without paragraph (b)(2)(v):
    (iv) VOC, NOX, oxides of sulfur (SOX) and/or 
ammonia (NH3) in PM2.5 areas if the EPA Regional 
Administrator or the director of the State air agency has made a 
finding that transportation-related emissions of any of these 
precursors within the nonattainment area are a significant contributor 
to the PM2.5 nonattainment problem and has so notified the 
MPO and DOT, or if the applicable implementation plan (or 
implementation plan submission) establishes an approved (or adequate) 
budget for such emissions as part of the reasonable further progress, 
attainment or maintenance strategy.
    (3) The provisions of this subpart apply to PM2.5 
nonattainment and maintenance areas with respect to PM2.5 
from re-entrained road dust if the EPA Regional Administrator or the 
director of the State air agency has made a finding that re-entrained 
road dust emissions within the area are a significant contributor to 
the PM2.5 nonattainment problem and has so notified the MPO 
and DOT, or if the applicable implementation plan (or implementation 
plan submission) includes re-entrained road dust in the approved (or 
adequate) budget as part of the reasonable further progress, attainment 
or maintenance strategy. Re-entrained road dust emissions are produced 
by travel on paved and unpaved roads (including emissions from anti-
skid and deicing materials).
* * * * *
    (d) Grace period for new nonattainment areas. For areas or portions 
of areas which have been continuously designated attainment or not 
designated for any NAAQS for ozone, CO, PM10, 
PM2.5 or NO2 since 1990 and are subsequently 
redesignated to nonattainment or designated nonattainment for any NAAQS 
for any of these pollutants, the provisions of this subpart shall not 
apply with respect to that standard for 12 months following the 
effective date of final designation to nonattainment for each NAAQS for 
such pollutant.
    4. Section 93.105(c)(1)(vii) is amended by revising the reference 
``Sec.  93.109(g)(2)(iii)'' to read ``Sec.  93.109(l)(2)(iii)''.
    5. Section 93.106 is amended by revising paragraph (b) to read as 
follows:


Sec.  93.106  Content of transportation plans.

* * * * *
    (b) Two-year grace period for transportation plan requirements in 
certain ozone and CO areas. The requirements of paragraph (a) of this 
section shall not apply for two years from the following:
    (i) The effective date of EPA's reclassification of a moderate 
ozone or CO area that has an urbanized area population greater than 
200,000 to serious or severe (ozone only); or,
    (ii) The official notice by the Census Bureau that determines the 
urbanized area population of a serious or above ozone or CO area to be 
greater than 200,000.
* * * * *
    6. Section 93.109 is amended by:
    a. Revising the paragraph (b) introductory text;
    b. In Table 1 of paragraph (b), revising the entry for ``Sec.  
93.118 and or Sec.  93.119'' under ``Transportation Plan:'' and the 
entry for ``Sec.  93.118 and or Sec.  93.119'' under ``TIP:'', and 
revising the entry for ``Sec.  93.117'' under ``Project (From a 
Conforming Plan and TIP):'' and the entries for ``Sec.  93.117'' and 
``Sec.  93.118 and or Sec.  93.119'' under ``Project (Not From a 
Conforming Plan and TIP):'';
    c. Revising paragraph (c);
    d. Redesignating paragraphs (d), (e), (f) and (g) as paragraphs 
(f), (g), (h) and (l);
    e. Adding new paragraphs (d), (e), (i), (j) and (k);
    f. Revising newly designated paragraphs (f) introductory text, 
(f)(2), (f)(3) and (f)(4)(i) and (ii);
    g. Revising newly redesignated paragraphs (g) introductory text, 
(g)(2), and (g)(3) introductory text, and removing newly designated 
paragraphs (g)(3)(i) and (g)(3)(ii) and redesignating paragraph 
(g)(3)(iii) as (g)(3)(ii) and adding new paragraph (g)(3)(i);
    h. Revising newly designated paragraph (h); and
    i. Revising newly designated paragraph (l)(2) introductory text; 
and, in newly designated paragraph (l)(2)(ii)(B), revising ``Sec.  
93.119(d)(2)'' to read ``Sec.  93.119(f)(2)''; and, in newly 
redesignated paragraph (l)(2)(iii), revising ``paragraph (g)(2)(ii)'' 
and ``paragraph (g)(2)(ii)(C)'' to read ``paragraph (l)(2)(ii)'' and 
``paragraph (l)(2)(ii)(C)'', respectively.
    The revisions and additions read as follows:


Sec.  93.109  Criteria and procedures for determining conformity of 
transportation plans, programs, and projects: General.

* * * * *
    (b) Table 1 in this paragraph indicates the criteria and procedures 
in Sec. Sec.  93.110 through 93.119 which apply for transportation 
plans, TIPs, and FHWA/FTA projects. Paragraphs (c) through (i) of this 
section explain when the budget, interim emissions, and hot-spot tests 
are required for each pollutant and NAAQS. Paragraph (j) of this 
section addresses conformity requirements for areas with approved or 
adequate limited maintenance plans. Paragraph (k) of this section 
addresses nonattainment and maintenance areas which EPA has determined 
have insignificant motor vehicle emissions. Paragraph (l) of this 
section addresses isolated rural nonattainment and maintenance areas. 
Table 1 follows:

                      Table 1.--Conformity Criteria
------------------------------------------------------------------------
 
------------------------------------------------------------------------
                              * * * * * * *
Transportation plan:
                              * * * * * * *
    Sec.   93.118 and/or Sec.   93.119.  Emissions budget and/or Interim
                                          emissions.
                              * * * * * * *
TIP:
                              * * * * * * *
    Sec.   93.118 and/or Sec.   93.119.  Emissions budget and/or Interim
                                          emissions.
                              * * * * * * *
Project (From a Conforming Plan and
 TIP):
                              * * * * * * *
    Sec.   93.117......................  PM10 and PM2.5 control
                                          measures.

[[Page 62724]]

 
                              * * * * * * *
Project (Not From a Conforming Plan and
 TIP):
                              * * * * * * *
    Sec.   93.117......................  PM10 and PM2.5 control
                                          measures.
    Sec.   93.118 and/or Sec.   93.119.  Emissions budget and/or Interim
                                          emissions.
                              * * * * * * *
------------------------------------------------------------------------

    (c) 1-hour ozone NAAQS nonattainment and maintenance areas. This 
paragraph applies when an area is nonattainment or maintenance for the 
1-hour ozone NAAQS (i.e., until the effective date of any revocation of 
the 1-hour ozone NAAQS for an area). In addition to the criteria listed 
in Table 1 in paragraph (b) of this section that are required to be 
satisfied at all times, in such ozone nonattainment and maintenance 
areas conformity determinations must include a demonstration that the 
budget and/or interim emissions tests are satisfied as described in the 
following:
    (1) In all 1-hour ozone nonattainment and maintenance areas the 
budget test must be satisfied as required by Sec.  93.118 for 
conformity determinations made on or after:
    (i) The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted control strategy implementation plan 
revision or maintenance plan for the 1-hour ozone NAAQS is adequate for 
transportation conformity purposes;
    (ii) The publication date of EPA's approval of such a budget in the 
Federal Register; or
    (iii) The effective date of EPA's approval of such a budget in the 
Federal Register, if such approval is completed through direct final 
rulemaking.
    (2) In ozone nonattainment areas that are required to submit a 
control strategy implementation plan revision for the 1-hour ozone 
NAAQS (usually moderate and above areas), the interim emissions tests 
must be satisfied as required by Sec.  93.119 for conformity 
determinations made when there is no approved motor vehicle emissions 
budget from an applicable implementation plan for the 1-hour ozone 
NAAQS and no adequate motor vehicle emissions budget from a submitted 
control strategy implementation plan revision or maintenance plan for 
the 1-hour ozone NAAQS.
    (3) An ozone nonattainment area must satisfy the interim emissions 
test for NOx, as required by Sec.  93.119, if the 
implementation plan or plan submission that is applicable for the 
purposes of conformity determinations is a 15% plan or Phase I 
attainment demonstration that does not include a motor vehicle 
emissions budget for NOx. The implementation plan for the 1-
hour ozone NAAQS will be considered to establish a motor vehicle 
emissions budget for NOx if the implementation plan or plan 
submission contains an explicit NOx motor vehicle emissions 
budget that is intended to act as a ceiling on future NOx 
emissions, and the NOx motor vehicle emissions budget is a 
net reduction from NOx emissions levels in 1990.
    (4) Ozone nonattainment areas that have not submitted a maintenance 
plan and that are not required to submit a control strategy 
implementation plan revision for the 1-hour ozone NAAQS (usually 
marginal and below areas) must satisfy one of the following 
requirements:
    (i) The interim emissions tests required by Sec.  93.119; or
    (ii) The State shall submit to EPA an implementation plan revision 
for the 1-hour ozone NAAQS that contains motor vehicle emissions 
budget(s) and a reasonable further progress or attainment 
demonstration, and the budget test required by Sec.  93.118 must be 
satisfied using the adequate or approved motor vehicle emissions 
budget(s) (as described in paragraph (c)(1) of this section).
    (5) Notwithstanding paragraphs (c)(1) and (c)(2) of this section, 
moderate and above ozone nonattainment areas with three years of clean 
data that have not submitted a maintenance plan and that EPA has 
determined are not subject to the Clean Air Act reasonable further 
progress and attainment demonstration requirements for the 1-hour ozone 
NAAQS must satisfy one of the following requirements:
    (i) The interim emissions tests as required by Sec.  93.119;
    (ii) The budget test as required by Sec.  93.118, using the 
adequate or approved motor vehicle emissions budgets in the submitted 
or applicable control strategy implementation plan for the 1-hour ozone 
NAAQS (subject to the timing requirements of paragraph (c)(1) of this 
section); or
    (iii) The budget test as required by Sec.  93.118, using the motor 
vehicle emissions of ozone precursors in the most recent year of clean 
data as motor vehicle emissions budgets, if such budgets are 
established by the EPA rulemaking that determines that the area has 
clean data for the 1-hour ozone NAAQS.
    (d) 8-hour ozone NAAQS nonattainment and maintenance areas without 
motor vehicle emissions budgets for the 1-hour ozone NAAQS for any 
portion of the 8-hour nonattainment area. This paragraph applies to 
areas that were never designated nonattainment for the 1-hour ozone 
NAAQS and areas that were designated nonattainment for the 1-hour ozone 
NAAQS but that never submitted a control strategy SIP or maintenance 
plan with approved or adequate motor vehicle emissions budgets. This 
paragraph applies 1 year after the effective date of EPA's 
nonattainment designation for the 8-hour ozone NAAQS, according to 
Sec.  93.102(d). In addition to the criteria listed in Table 1 in 
paragraph (b) of this section that are required to be satisfied at all 
times, in such 8-hour ozone nonattainment and maintenance areas 
conformity determinations must include a demonstration that the budget 
and/or interim emissions tests are satisfied as described in the 
following:
    (1) In such 8-hour ozone nonattainment and maintenance areas the 
budget test must be satisfied as required by Sec.  93.118 for 
conformity determinations made on or after:
    (i) The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted control strategy implementation plan 
revision or maintenance plan for the 8-hour ozone NAAQS is adequate for 
transportation conformity purposes;
    (ii) The publication date of EPA's approval of such a budget in the 
Federal Register; or
    (iii) The effective date of EPA's approval of such a budget in the 
Federal Register, if such approval is completed through direct final 
rulemaking.
    (2) In ozone nonattainment areas that are required to submit a 
control strategy

[[Page 62725]]

implementation plan revision for the 8-hour ozone NAAQS (moderate and 
above and certain subpart 1 areas), the interim emissions tests must be 
satisfied as required by Sec.  93.119 for conformity determinations 
made when there is no approved motor vehicle emissions budget from an 
applicable implementation plan for the 8-hour ozone NAAQS and no 
adequate motor vehicle emissions budget from a submitted control 
strategy implementation plan revision or maintenance plan for the 8-
hour ozone NAAQS.
    (3) Such an 8-hour ozone nonattainment area must satisfy the 
interim emissions test for NOx, as required by Sec.  93.119, 
if the implementation plan or plan submission that is applicable for 
the purposes of conformity determinations is a 15% plan or other 
control strategy SIP that addresses reasonable further progress that 
does not include a motor vehicle emissions budget for NOx. 
The implementation plan for the 8-hour ozone NAAQS will be considered 
to establish a motor vehicle emissions budget for NOx if the 
implementation plan or plan submission contains an explicit 
NOx motor vehicle emissions budget that is intended to act 
as a ceiling on future NOx emissions, and the NOx 
motor vehicle emissions budget is a net reduction from NOx 
emissions levels in 2002.
    (4) Ozone nonattainment areas that have not submitted a maintenance 
plan and that are not required to submit a control strategy 
implementation plan revision for the 8-hour ozone NAAQS (usually 
marginal and below areas) must satisfy one of the following 
requirements:
    (i) The interim emissions tests required by Sec.  93.119; or
    (ii) The State shall submit to EPA an implementation plan revision 
for the 8-hour ozone NAAQS that contains motor vehicle emissions 
budget(s) and a reasonable further progress or attainment 
demonstration, and the budget test required by Sec.  93.118 must be 
satisfied using the adequate or approved motor vehicle emissions 
budget(s) (as described in paragraph (d)(1) of this section).
    (5) Notwithstanding paragraphs (d)(1) and (d)(2) of this section, 
moderate and above ozone nonattainment areas with three years of clean 
data for the 8-hour ozone NAAQS that have not submitted a maintenance 
plan and that EPA has determined are not subject to the Clean Air Act 
reasonable further progress and attainment demonstration requirements 
for the 8-hour ozone NAAQS must satisfy one of the following 
requirements:
    (i) The interim emissions tests as required by Sec.  93.119;
    (ii) The budget test as required by Sec.  93.118, using the 
adequate or approved motor vehicle emissions budgets in the submitted 
or applicable control strategy implementation plan for the 8-hour ozone 
NAAQS (subject to the timing requirements of paragraph (d)(1) of this 
section); or
    (iii) The budget test as required by Sec.  93.118, using the motor 
vehicle emissions of ozone precursors in the most recent year of clean 
data as motor vehicle emissions budgets, if such budgets are 
established by the EPA rulemaking that determines that the area has 
clean data for the 8-hour ozone NAAQS.
    (e) 8-hour ozone NAAQS nonattainment and maintenance areas with 
motor vehicle emissions budgets for the 1-hour ozone NAAQS that cover 
all or a portion of the 8-hour nonattainment area. This provision 
applies 1 year after the effective date of EPA's nonattainment 
designation for the 8-hour ozone NAAQS, according to Sec.  93.102(d). 
In addition to the criteria listed in Table 1 in paragraph (b) of this 
section that are required to be satisfied at all times, in such 8-hour 
ozone nonattainment and maintenance areas conformity determinations 
must include a demonstration that the budget and/or interim emissions 
tests are satisfied as described in the following:
    (1) In such 8-hour ozone nonattainment and maintenance areas the 
budget test must be satisfied as required by Sec. Sec.  93.118 for 
conformity determinations made on or after:
    (i) The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted control strategy implementation plan 
revision or maintenance plan for the 8-hour ozone NAAQS is adequate for 
transportation conformity purposes;
    (ii) The publication date of EPA's approval of such a budget in the 
Federal Register; or
    (iii) The effective date of EPA's approval of such a budget in the 
Federal Register, if such approval is completed through direct final 
rulemaking.
    (2) Prior to the effective date of EPA's finding that a motor 
vehicle emissions budget in a submitted control strategy implementation 
plan or maintenance plan for the 8-hour ozone NAAQS is adequate or the 
publication of EPA's approval of such a budget in the Federal Register, 
one of the following test(s) must be satisfied:
    (i) The interim emissions tests as required by Sec.  93.119 for the 
entire 8-hour ozone nonattainment area; or
    (ii) The budget test and interim emissions tests as required by 
Sec. Sec.  93.118 and 93.119 as follows:
    (A) If the 8-hour ozone nonattainment area covers the same 
geographic area as the 1-hour ozone nonattainment or maintenance area, 
the budget test as required by Sec.  93.118 for the entire 8-hour 
nonattainment area using the approved or adequate motor vehicle 
emissions budgets in the 1-hour ozone applicable implementation plan or 
implementation plan submission;
    (B) If the 8-hour ozone nonattainment area covers a smaller 
geographic area within the 1-hour ozone nonattainment or maintenance 
area, the budget test as required by Sec.  93.118 for either the 1-hour 
nonattainment or 8-hour nonattainment area using the approved or 
adequate motor vehicle emissions budgets or corresponding portions 
thereof in the 1-hour ozone applicable implementation plan or 
implementation plan submission, respectively. If additional control 
measures are necessary to meet the budget test for the 8-hour ozone 
NAAQS, such control measures could only be established within the 8-
hour nonattainment area; or
    (C) If the 8-hour ozone nonattainment area covers a larger 
geographic area and encompasses the entire or a portion of the 1-hour 
ozone nonattainment or maintenance area:
    (1) The budget test as required by Sec.  93.118 for the portion of 
the 8-hour ozone nonattainment area covered by the approved or adequate 
motor vehicle emissions budgets or corresponding portions thereof in 
the 1-hour ozone applicable implementation plan or implementation plan 
submission; and
    (2) The interim emissions tests as required by Sec.  93.119 for the 
portion of the 8-hour ozone nonattainment area not covered by the 
approved or adequate budgets in the 1-hour ozone implementation plan.
    (3) Such an 8-hour ozone nonattainment area must satisfy the 
interim emissions test for NOX, as required by Sec.  93.119, 
if the only implementation plan or plan submission that is applicable 
for the purposes of conformity determinations is a 15% plan or other 
control strategy SIP that addresses reasonable further progress that 
does not include a motor vehicle emissions budget for NOX. 
The implementation plan for the 8-hour ozone NAAQS will be considered 
to establish a motor vehicle emissions budget for NOX if the 
implementation plan or plan submission contains an

[[Page 62726]]

explicit NOX motor vehicle emissions budget that is intended 
to act as a ceiling on future NOX emissions, and the 
NOX motor vehicle emissions budget is a net reduction from 
NOX emissions levels in 2002. Prior to an adequate or 
approved NOX motor vehicle emissions budget in the 
implementation plan submission for the 8-hour ozone NAAQS, the 
implementation plan for the 1-hour ozone NAAQS will be considered to 
establish a motor vehicle emissions budget for NOX if the 
implementation plan contains an explicit NOX motor vehicle 
emissions budget that is intended to act as a ceiling on future 
NOX emissions, and the NOX motor vehicle 
emissions budget is a net reduction from NOX emissions 
levels in 1990.
    (4) Notwithstanding paragraphs (e)(1) and (e)(2) of this section, 
ozone nonattainment areas with three years of clean data for the 8-hour 
ozone NAAQS that have not submitted a maintenance plan and that EPA has 
determined are not subject to the Clean Air Act reasonable further 
progress and attainment demonstration requirements for the 8-hour ozone 
NAAQS must satisfy one of the following requirements:
    (i) The interim emissions tests as required by Sec.  93.119 and as 
described in paragraph (e)(2) of this section;
    (ii) The budget test as required by Sec.  93.118 and as described 
in paragraph (e)(2)(ii) of this section;
    (iii) The budget test as required by Sec.  93.118, using the 
adequate or approved motor vehicle emissions budgets in the submitted 
or applicable control strategy implementation plan for the 8-hour ozone 
NAAQS (subject to the timing requirements of paragraph (e)(1) of this 
section); or
    (iv) The budget test as required by Sec.  93.118, using the motor 
vehicle emissions of ozone precursors in the most recent year of clean 
data as motor vehicle emissions budgets, if such budgets are 
established by the EPA rulemaking that determines that the area has 
clean data for the 8-hour ozone NAAQS.
    (f) CO nonattainment and maintenance areas. In addition to the 
criteria listed in Table 1 in paragraph (b) of this section that are 
required to be satisfied at all times, in CO nonattainment and 
maintenance areas conformity determinations must include a 
demonstration that the hot-spot, budget and/or interim emissions tests 
are satisfied as described in the following:
* * * * *
    (2) In CO nonattainment and maintenance areas the budget test must 
be satisfied as required by Sec.  93.118 for conformity determinations 
made on or after:
    (i) The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted control strategy implementation plan 
revision or maintenance plan is adequate for transportation conformity 
purposes;
    (ii) The publication date of EPA's approval of such a budget in the 
Federal Register; or
    (iii) The effective date of EPA's approval of such a budget in the 
Federal Register, if such approval is completed through direct final 
rulemaking.
    (3) Except as provided in paragraph (d)(4) of this section, in CO 
nonattainment areas the interim emissions tests must be satisfied as 
required by Sec.  93.119 for conformity determinations made when there 
is no approved motor vehicle emissions budget from an applicable 
implementation plan and no adequate motor vehicle emissions budget from 
a submitted control strategy implementation plan revision or 
maintenance plan.
    (4) * * *
    (i) The interim emissions tests required by Sec.  93.119; or
    (ii) The State shall submit to EPA an implementation plan revision 
that contains motor vehicle emissions budget(s) and an attainment 
demonstration, and the budget test required by Sec.  93.118 must be 
satisfied using the adequate or approved motor vehicle emissions 
budget(s) (as described in paragraph (f)(2) of this section).
    (g) PM10 nonattainment and maintenance areas. In 
addition to the criteria listed in Table 1 in paragraph (b) of this 
section that are required to be satisfied at all times, in 
PM10 nonattainment and maintenance areas conformity 
determinations must include a demonstration that the hot-spot, budget 
and/or interim emissions tests are satisfied as described in the 
following:
* * * * *
    (2) In PM10 nonattainment and maintenance areas the 
budget test must be satisfied as required by Sec.  93.118 for 
conformity determinations made on or after:
    (i) The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted control strategy implementation plan 
revision or maintenance plan is adequate for transportation conformity 
purposes;
    (ii) The publication date of EPA's approval of such a budget in the 
Federal Register; or
    (iii) The effective date of EPA's approval of such a budget in the 
Federal Register, if such approval is completed through direct final 
rulemaking.
    (3) In PM10 nonattainment areas the interim emissions 
tests must be satisfied as required by Sec.  93.119 for conformity 
determinations made:
    (i) If there is no approved motor vehicle emissions budget from an 
applicable implementation plan and no adequate motor vehicle emissions 
budget from a submitted control strategy implementation plan revision 
or maintenance plan; or
* * * * *
    (h) NO2 nonattainment and maintenance areas. In addition 
to the criteria listed in Table 1 in paragraph (b) of this section that 
are required to be satisfied at all times, in NO2 
nonattainment and maintenance areas conformity determinations must 
include a demonstration that the budget and/or interim emissions tests 
are satisfied as described in the following:
    (1) In NO2 nonattainment and maintenance areas the 
budget test must be satisfied as required by Sec.  93.118 for 
conformity determinations made on or after:
    (i) The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted control strategy implementation plan 
revision or maintenance plan is adequate for transportation conformity 
purposes;
    (ii) The publication date of EPA's approval of such a budget in the 
Federal Register; or
    (iii) The effective date of EPA's approval of such a budget in the 
Federal Register, if such approval is completed through direct final 
rulemaking.
    (2) In NO2 nonattainment areas the interim emissions 
tests must be satisfied as required by Sec.  93.119 for conformity 
determinations made when there is no approved motor vehicle emissions 
budget from an applicable implementation plan and no adequate motor 
vehicle emissions budget from a submitted control strategy 
implementation plan revision or maintenance plan.
    (i) PM2.5 nonattainment and maintenance areas. In 
addition to the criteria listed in Table 1 in paragraph (b) of this 
section that are required to be satisfied at all times, in 
PM2.5 nonattainment and maintenance areas conformity 
determinations must include a demonstration that the budget and/or 
interim emissions tests are satisfied as described in the following:
    (1) In PM2.5 nonattainment and maintenance areas the 
budget test must be satisfied as required by Sec.  93.118 for

[[Page 62727]]

conformity determinations made on or after:
    (i) The effective date of EPA's finding that a motor vehicle 
emissions budget in a submitted control strategy implementation plan 
revision or maintenance plan is adequate for transportation conformity 
purposes;
    (ii) The publication date of EPA's approval of such a budget in the 
Federal Register; or
    (iii) The effective date of EPA's approval of such a budget in the 
Federal Register, if such approval is completed through direct final 
rulemaking.
    (2) In PM2.5 nonattainment areas the interim emissions 
tests must be satisfied as required by Sec.  93.119 for conformity 
determinations made if there is no approved motor vehicle emissions 
budget from an applicable implementation plan and no adequate motor 
vehicle emissions budget from a submitted control strategy 
implementation plan revision or maintenance plan.
    (j) Areas with limited maintenance plans. Notwithstanding the other 
paragraphs of this section, an area is not required to satisfy the 
regional emissions analysis for Sec.  93.118 and/or Sec.  93.119 for a 
given pollutant and NAAQS, if the area has an adequate or approved 
limited maintenance plan for such pollutant and NAAQS. A limited 
maintenance plan would have to demonstrate that it would be 
unreasonable to expect that such an area would experience enough motor 
vehicle emissions growth for a NAAQS violation to occur. A conformity 
determination that meets other applicable criteria in Table 1 of 
paragraph (b) of this section is still required, including the hot-spot 
requirements for projects in CO and PM10 areas.
    (k) Areas with insignificant motor vehicle emissions. 
Notwithstanding the other paragraphs in this section, an area is not 
required to satisfy a regional emissions analysis for Sec.  93.118 and/
or Sec.  93.119 for a given pollutant/precursor and NAAQS, if EPA finds 
through the adequacy or approval process that a SIP demonstrates that 
regional motor vehicle emissions are an insignificant contributor to 
the air quality problem for that pollutant/precursor and NAAQS. The SIP 
would have to demonstrate that it would be unreasonable to expect that 
such an area would experience enough motor vehicle emissions growth in 
that pollutant/precursor for a NAAQS violation to occur. Such a finding 
would be based on a number of factors, including the percentage of 
motor vehicle emissions in the context of the total SIP inventory, the 
current state of air quality as determined by monitoring data for that 
NAAQS, the absence of SIP motor vehicle control measures, and 
historical trends and future projections of the growth of motor vehicle 
emissions. A conformity determination that meets other applicable 
criteria in Table 1 of paragraph (b) of this section is still required, 
including regional emissions analyses for Sec.  93.118 and/or Sec.  
93.119 for other pollutants/precursors and NAAQS that apply. Hot-spot 
requirements for projects in CO and PM10 areas must also be 
satisfied, unless EPA determines that the SIP demonstrates that hot-
spot emissions are also insignificant. If EPA subsequently finds that 
motor vehicle emissions of a given pollutant/precursor are significant, 
this paragraph would no longer apply for future conformity 
determinations for that pollutant/precursor and NAAQS.
    (1) * * *
    (2) Isolated rural nonattainment and maintenance areas are subject 
to the budget and/or interim emissions tests as described in paragraphs 
(c) through (k) of this section, with the following modifications:
* * * * *
    7. Section 93.117 is revised to read as follows:


Sec.  93.117   Criteria and procedures: Compliance with PM10 
and PM2.5 control measures.

    The FHWA/FTA project must comply with any PM10 and 
PM2.5 control measures in the applicable implementation 
plan. This criterion is satisfied if the project-level conformity 
determination contains a written commitment from the project sponsor to 
include in the final plans, specifications, and estimates for the 
project those control measures (for the purpose of limiting 
PM10 and PM2.5 emissions from the construction 
activities and/or normal use and operation associated with the project) 
that are contained in the applicable implementation plan.
    8. In Sec.  93.118, paragraph (a) is amended by revising the 
reference ``Sec.  93.109(c) through (g)'' to read ``Sec.  93.109(c) 
through (l)'', and paragraph (e)(2) is amended by revising the phrase 
``emission reduction tests required by Sec.  93.119'' to read ``interim 
emissions tests required by Sec.  93.119''.
    9. Section 93.119 is amended by:
    a. Revising paragraphs (a) and (b);
    b. Redesignating paragraphs (c), (d), (e), (f), (g) and (h) as 
paragraphs (d), (f), (g), (h), (i) and (j);
    c. Adding new paragraphs (c) and (e);
    d. Revising newly redesignated paragraphs (d) introductory text and 
(d)(1);
    e. Revising newly redesignated paragraph (f)(5), removing the 
period at the end of newly redesignated paragraph (f)(6) and adding a 
semicolon in its place, and adding new paragraphs (f)(7) and (f)(8), 
(f)(9) and (f)(10);
    f. Revising newly redesignated paragraph (g);
    g. In newly redesignated paragraphs (h) introductory text and (i) 
introductory text, revising the reference ``paragraphs (b) and (c)'' to 
read ``paragraphs (b) through (e) ''; and,
    h. In newly redesignated paragraph (j), revising the reference 
``paragraphs (b) and (c)'' to read ``paragraphs (b) through (e) ''.
    The revisions and additions read as follows:


Sec.  93.119  Criteria and procedures: Interim emissions in areas 
without motor vehicle emissions budgets.

    (a) The transportation plan, TIP, and project not from a conforming 
transportation plan and TIP must satisfy the interim emissions test(s) 
as described in Sec.  93.109(c) through (l). This criterion applies to 
the net effect of the action (transportation plan, TIP, or project not 
from a conforming plan and TIP) on motor vehicle emissions from the 
entire transportation system.
    (b) Ozone areas. The requirements of this paragraph apply to all 1-
hour ozone and 8-hour ozone NAAQS areas, except for certain 
requirements as indicated. This criterion may be met:
    (1) In moderate and above ozone nonattainment areas that are 
subject to the reasonable further progress requirements of CAA section 
182(b)(1) if a regional emissions analysis that satisfies the 
requirements of Sec.  93.122 and paragraphs (g) through (j) of this 
section demonstrates that for each analysis year and for each of the 
pollutants described in paragraph (f) of this section:
    (i) The emissions predicted in the ``Action'' scenario are less 
than the emissions predicted in the ``Baseline'' scenario, and this can 
be reasonably expected to be true in the periods between the analysis 
years; and
    (ii) The emissions predicted in the ``Action'' scenario are lower 
than:
    (A) 1990 emissions by any nonzero amount, in areas for the 1-hour 
ozone NAAQS as described in Sec.  93.109(c); or
    (B) 2002 emissions by any nonzero amount, in areas for the 8-hour 
ozone NAAQS as described in Sec.  93.109(d) and (e).
    (2) In marginal and below ozone nonattainment areas and other ozone

[[Page 62728]]

nonattainment areas that are not subject to the reasonable further 
progress requirements of CAA section 182(b)(1) if a regional emissions 
analysis that satisfies the requirements of Sec.  93.122 and paragraphs 
(g) through (j) of this section demonstrates that for each analysis 
year and for each of the pollutants described in paragraph (f) of this 
section:
    (i) The emissions predicted in the ``Action'' scenario are not 
greater than the emissions predicted in the ``Baseline'' scenario, and 
this can be reasonably expected to be true in the periods between the 
analysis years; or
    (ii) The emissions predicted in the ``Action'' scenario are not 
greater than:
    (A) 1990 emissions, in areas for the 1-hour ozone NAAQS as 
described in Sec.  93.109(c); or
    (B) 2002 emissions, in areas for the 8-hour ozone NAAQS as 
described in Sec.  93.109(d) and (e).
    (c) CO areas. This criterion may be met:
    (1) In moderate areas with design value greater than 12.7 ppm and 
serious CO nonattainment areas that are subject to CAA section 
187(a)(7) if a regional emissions analysis that satisfies the 
requirements of Sec.  93.122 and paragraphs (g) through (j) of this 
section demonstrates that for each analysis year and for each of the 
pollutants described in paragraph (f) of this section:
    (i) The emissions predicted in the ``Action'' scenario are less 
than the emissions predicted in the ``Baseline'' scenario, and this can 
be reasonably expected to be true in the periods between the analysis 
years; and
    (ii) The emissions predicted in the ``Action'' scenario are lower 
than 1990 emissions by any nonzero amount.
    (2) In moderate areas with design value less than 12.7 ppm and not 
classified CO nonattainment areas if a regional emissions analysis that 
satisfies the requirements of Sec.  93.122 and paragraphs (g) through 
(j) of this section demonstrates that for each analysis year and for 
each of the pollutants described in paragraph (f) of this section:
    (i) The emissions predicted in the ``Action'' scenario are not 
greater than the emissions predicted in the ``Baseline'' scenario, and 
this can be reasonably expected to be true in the periods between the 
analysis years; or
    (ii) the emissions predicted in the ``Action'' scenario are not 
greater than 1990 emissions.
    (d) PM10 and NO2 areas. This criterion may be 
met in PM10 and NO2 nonattainment areas if a 
regional emissions analysis that satisfies the requirements of Sec.  
93.122 and paragraphs (g) through (j) of this section demonstrates that 
for each analysis year and for each of the pollutants described in 
paragraph (f) of this section, one of the following requirements is 
met:
    (1) The emissions predicted in the ``Action'' scenario are not 
greater than the emissions predicted in the ``Baseline'' scenario, and 
this can be reasonably expected to be true in the periods between the 
analysis years; or
* * * * *
    (e) PM2.5 areas. This criterion may be met in 
PM2.5 nonattainment areas if a regional emissions analysis 
that satisfies the requirements of Sec.  93.122 and paragraphs (g) 
through (j) of this section demonstrates that for each analysis year 
and for each of the pollutants described in paragraph (f) of this 
section, one of the following requirements is met:
    (1) The emissions predicted in the ``Action'' scenario are not 
greater than the emissions predicted in the ``Baseline'' scenario, and 
this can be reasonably expected to be true in the periods between the 
analysis years; or
    (2) The emissions predicted in the ``Action'' scenario are not 
greater than 2002 emissions.
    (f) * * *
* * * * *
    (5) VOC and/or NOX in PM10 areas if the EPA 
Regional Administrator or the director of the State air agency has made 
a finding that one or both of such precursor emissions from within the 
area are a significant contributor to the PM10 nonattainment 
problem and has so notified the MPO and DOT;
    (6) NOX in NO2 areas;
    (7) PM2.5 in PM2.5 areas;
    Option 1 for paragraphs (f)(8), (f)(9) and (f)(10):
    (8) VOC and/or NOX in PM2.5 areas, unless the 
EPA Regional Administrator or the director of the State air agency has 
made a finding that one or both of such precursor emissions from within 
the area are not a significant contributor to the PM2.5 
nonattainment problem and has so notified the MPO and DOT;
    (9) SOx and/or NH3 in PM2.5 areas 
if the EPA Regional Administrator or the director of the State air 
agency has made a finding that one or both of such precursor emissions 
from within the area are a significant contributor to the 
PM2.5 nonattainment problem and has so notified the MPO and 
DOT; and
    (10) Re-entrained road dust in PM2.5 areas if the EPA 
Regional Administrator or the director of the State air agency has made 
a finding that emissions from re-entrained road dust within the area 
are a significant contributor to the PM2.5 nonattainment 
problem and has so notified the MPO and DOT.
    Option 2 for paragraphs (f)(8) and (f)(9) without paragraph 
(f)(10):
    (8) NOX, VOC, SOx and/or NH3 in 
PM2.5 areas if the EPA Regional Administrator or the 
director of the State air agency has made a finding that one or more of 
such precursor emissions from within the area are a significant 
contributor to the PM2.5 nonattainment problem and has so 
notified the MPO and DOT; and
    (9) Reentrained road dust in PM2.5 areas if the EPA 
Regional Administrator or the director of the State air agency has made 
a finding that emissions from reentrained road dust within the area are 
a significant contributor to the PM2.5 nonattainment problem 
and has so notified the MPO and DOT.
    (g) Analysis years. (1) The regional emissions analysis must be 
performed for analysis years that are no more than ten years apart. The 
first analysis year must be no more than five years beyond the year in 
which the conformity determination is being made. The last year of the 
transportation plan's forecast period must also be an analysis year.
    (2) For areas using paragraphs (b)(2)(i), (c)(2)(i), (d)(1), and 
(e)(1) of this section, a regional emissions analysis that satisfies 
the requirements of Sec.  93.122 and paragraphs (g) through (j) of this 
section would not be required for analysis years in which the 
transportation projects and planning assumptions in the ``Action'' and 
``Baseline'' scenarios are exactly the same. In such a case, paragraph 
(a) of this section can be satisfied by documenting that the 
transportation projects and planning assumptions in both scenarios are 
exactly the same, and consequently, the emissions predicted in the 
``Action'' scenario are not greater than the emissions predicted in the 
``Baseline'' scenario for such analysis years.
    10. Section 93.121 is amended by revising paragraph (b) 
introductory text by removing the reference ``Sec.  93.109(g)'' and 
adding in its place a reference for ``Sec.  93.109(l)'', and revising 
paragraph (b)(1) and adding new paragraph (c) to read as follows:



Sec.  93.121  Requirements for adoption or approval of projects by 
other recipients of funds designated under title 23 U.S.C. or the 
Federal Transit Laws.

* * * * *
    (b) * * *
    (1) The project was included in the regional emissions analysis 
supporting the most recent conformity determination that reflects the 
portion of the statewide transportation plan and TIP which are in the 
nonattainment or maintenance area, and the project's

[[Page 62729]]

design concept and scope has not changed significantly; or
* * * * *
    (c) Notwithstanding paragraphs (a) and (b) of this section, in 
nonattainment and maintenance areas subject to Sec.  93.109(j) or (k) 
for a given pollutant/precursor and NAAQS, no recipient of Federal 
funds designated under title 23 U.S.C. or the Federal Transit Laws 
shall adopt or approve a regionally significant highway or transit 
project, regardless of funding source, unless the recipient finds that 
the requirements of one of the following are met for that pollutant/
precursor and NAAQS:
    (1) The project was included in the most recent conformity 
determination for the transportation plan and TIP and the project's 
design concept and scope has not changed significantly; or
    (2) The project was included in the most recent conformity 
determination that reflects the portion of the statewide transportation 
plan and TIP which are in the nonattainment or maintenance area, and 
the project's design concept and scope has not changed significantly.
    11. Section 93.122 is amended by:
    a. Redesignating paragraphs (c), (d), and (e) as paragraphs (d), 
(e) and (g), respectively;
    b. Adding new paragraphs (c) and (f); and
    c. In newly redesignated paragraph (g)(1), revising the reference 
to ``93.119 (``Emission reductions in areas without motor vehicle 
emissions budgets'')'' to read ``93.119 (``Interim emissions in areas 
without motor vehicle emissions budgets'')''.
    The revisions and additions read as follows:


Sec.  93.122  Procedures for determining regional transportation-
related emissions.

* * * * *
    (c) Two-year grace period for regional emissions analysis 
requirements in certain ozone and CO areas. The requirements of 
paragraph (b) of this section shall not apply for two years from the 
following:
    (i) The effective date of EPA's reclassification of a moderate 
ozone or CO area that has an urbanized area population greater than 
200,000 to serious or severe (ozone only); or,
    (ii) The official notice by the Census Bureau that determines the 
urbanized area population of a serious or above ozone or CO area to be 
greater than 200,000.
* * * * *
    (f) PM2.5 from construction-related fugitive dust. (1) 
For PM2.5 areas in which the implementation plan does not 
identify construction-related fugitive PM2.5 as a 
significant contributor to the nonattainment problem, the fugitive 
PM2.5 emissions associated with highway and transit project 
construction are not required to be considered in the regional 
emissions analysis.
    (2) In PM2.5 nonattainment and maintenance areas with 
implementation plans which identify construction-related fugitive 
PM2.5 as a significant contributor to the nonattainment 
problem, the regional PM2.5 emissions analysis shall 
consider construction-related fugitive PM2.5 and shall 
account for the level of construction activity, the fugitive 
PM2.5 control measures in the applicable implementation 
plan, and the dust-producing capacity of the proposed activities.
* * * * *


Sec.  93.125  [Amended]

    12. In Sec.  93.125, paragraph (a) is amended by revising the 
reference ``93.119 (``Emissions reductions in areas without motor 
vehicle emissions budgets'')'' to read ``93.119 (``Interim emissions in 
areas without motor vehicle emissions budgets'')'', and paragraph (d) 
is amended by revising the phrase ``emission reduction requirements of 
Sec.  93.119'' to read ``interim emissions requirements of Sec.  
93.119''.

[FR Doc. 03-27372 Filed 11-4-03; 8:45 am]
BILLING CODE 6560-50-P