[Federal Register Volume 67, Number 149 (Friday, August 2, 2002)]
[Proposed Rules]
[Pages 50391-50406]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-19441]


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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[LA-61-3-7561; FRL-7254-6]


Approval and Promulgation of Implementation Plan; State of 
Louisiana; 1-Hour Ozone Attainment Demonstration; Attainment Date 
Extension, and Withdrawal of Nonattainment Determination and 
Reclassification

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

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SUMMARY: EPA proposes to approve the Baton Rouge 1-hour ozone 
Attainment Plan and Transport State Implementation Plan (hereinafter 
referred to as Attainment Plan/Transport SIP) for the Baton Rouge 
serious ozone nonattainment area (hereinafter referred to as the Baton 
Rouge area). The attainment demonstration SIP, showing attainment by 
November 15, 2005, was submitted by the Governor of Louisiana on 
December 31, 2001. In conjunction with its proposed approval of the 
attainment demonstration, EPA proposes: extending the ozone attainment 
date for the Baton Rouge area to November 15, 2005, while retaining the 
area's current classification as a serious ozone nonattainment area; 
and withdrawing EPA's June 24, 2002, rulemaking determining 
nonattainment and reclassification of the Baton Rouge area. EPA is also 
proposing to find that the Baton Rouge area meets the reasonably 
available control measures (RACM) requirements of the Act.
    In proposing to approve the attainment demonstration, EPA is also 
proposing to approve the State's enforceable commitment to perform a 
mid-course review and submit a SIP revision to EPA by May 1, 2004, to 
approve the motor vehicle emissions budget (MVEB) and an enforceable 
commitment to submit revised budgets using MOBILE6, and an enforceable 
transportation control measure (TCM).
    This proposed rule also addresses SIP submittals relating to 
corrections to the 1990 Base Year Emissions Inventory, the 9% Rate-of-
Progress Plan, and the 15% Rate-of-Progress Plan.

DATES: Written comments must be received on or before September 3, 
2002.

ADDRESSES: All comments should be addressed to Mr. Thomas H. Diggs, 
Chief, Air Planning Section, Environmental Protection Agency, Region 6, 
1445 Ross Avenue, Dallas, Texas 75202-2733.
    Copies of the Louisiana submittals addressed in this proposed rule, 
and other relevant documents in support of this proposal are available 
for public inspection during normal business hours at the following 
addresses: U.S. Environmental Protection Agency, Region 6, Air Planning 
Section, 1445 Ross Avenue, Dallas, Texas 75202; Louisiana Department of 
Environmental Quality, 7920 Bluebonnet Boulevard, Baton Rouge, 
Louisiana 70884. Please contact the appropriate office at least 24 
hours in advance.

FOR FURTHER INFORMATION CONTACT: Ms. Maria L. Martinez, Air Planning 
Section (6PD-L), EPA Region 6, 1445 Ross Avenue, Dallas, Texas 75202-
2733, telephone (214) 665-2230.

SUPPLEMENTARY INFORMATION: The use of ``we,'' ``us,'' or ``our'' in 
this document refers to EPA.

Table of Contents

I. Background
    A. Basis for the State's Attainment Demonstration
    B. Components of a Modeled Attainment Demonstration
    C. Framework for Proposing Action on the Attainment 
Demonstration SIP

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    D. Criteria for Attainment Date Extensions
II. Technical Review of the Submittals
    A. Summary of the State Submittals
    1. General Information
    2. Modeling Procedures, Input Data, and Results
    3. Emission Control Strategies
    4. Motor Vehicle Emissions Budgets
    5. RACM Analysis and Determination of Availability
    6. Revisions to the 15% Rate-of-Progress Plan (ROPP) for the 
control of VOC emissions, the 1990 base year emissions inventory, 
and the Post-1996 ROPP.
    B. Environmental Protection Agency Review of the Submittals
    1. Adequacy of the State's Demonstration of Attainment
    2. Adequacy of the Emissions Control Strategies
    3. Adequacy of the Request for Extension of the Attainment Date
    a. Identification of the Area as a Downwind Area Affected by 
Ozone Transport
    b. Submittal of an Approvable Attainment Demonstration
    c. Adoption of all Applicable Local Measures Required Under the 
Area's Current Ozone Classification
    d. Implementation of All Adopted Measures as Expeditiously as 
Practicable and No Later Than the Time Upwind Controls are Expected.
    4. Determination of RACM Availability
    5. Adequacy of ROPPs and the 1990 Base Year Inventory
    6. Completeness Finding
III. Proposed Action
IV. Administrative Requirements

I. Background

A. Basis for State's Attainment Demonstration

What Are the Relevant Clean Air Act Requirements?
    The Clean Air Act (Act or CAA) requires EPA to establish National 
Ambient Air Quality Standards (NAAQS) for certain widespread pollutants 
that cause or contribute to air pollution that is reasonably 
anticipated to endanger public health or welfare, Clean Air Act 
sections 108 and 109. In 1979, EPA promulgated the 1-hour ground-level 
ozone standard of 0.12 parts per million (ppm) (120 parts per billion 
(ppb)). 44 FR 8202 (February 9, 1979).
    Ground-level ozone is not emitted directly by sources. Rather, VOC 
and Nitrogen oxides (NOX), emitted by a wide variety of 
sources, react in the presence of sunlight to form ground-level ozone. 
NOX and VOC are referred to as precursors of ozone.
    Ozone formation is accelerated or enhanced under certain 
meteorological conditions, such as high temperatures and low wind 
speeds. Higher ozone concentrations occur downwind of areas with 
relatively high VOC and NOX concentrations or in areas 
subject to relatively high background ozone and ozone precursor 
concentrations (ozone and ozone precursors entering an area as the 
result of transport from upwind source areas).
    VOC emissions are produced by a wide variety of sources, including 
stationary and mobile sources. Significant stationary sources of VOC 
include industrial solvent usage, various coating operations, 
industrial and utility combustion units, petroleum and oil storage and 
marketing operations, chemical manufacturing operations, and personal 
solvent usage. Significant mobile sources of VOC include on-road 
vehicle usage and off-road vehicle and engine usage, such as farm 
machinery, aircraft, locomotives, and motorized, lawn care and garden 
implements.
    NOX emissions are produced primarily through combustion 
processes, including industrial and utility boiler use, process heaters 
and furnaces, and on-road and off-road mobile sources.
    An area exceeds the 1-hour ozone standard each time an ambient air 
quality monitor records a 1-hour average ozone concentration above 
0.124 ppm in any given day (only the highest 1-hour ozone concentration 
at the monitor during any 24 hour day is considered when determining 
the number of exceedance days at the monitor). An area violates the 
ozone standard if, over a consecutive 3-year period, more than 3 days 
of exceedances occur at any monitor in the area. 40 CFR part 50, 
appendix H.
    The highest of the fourth-highest daily peak ozone concentrations 
over the 3 year period at any monitoring site in the area is called the 
ozone design value for the area. The Act, as amended in 1990, required 
EPA to designate as nonattainment any area that was violating the 1-
hour ozone standard, generally based on air quality monitoring data for 
the 3 year period from 1987 through 1989 period. Clean Air Act section 
107(d)(4); 56 FR 56694 (November 6, 1991). The Act further classified 
these areas, based on the areas' ozone design values, as marginal, 
moderate, serious, severe, or extreme. Marginal areas were suffering 
the least significant ozone nonattainment problems, while the areas 
classified as severe and extreme had the most significant ozone 
nonattainment problems.
    The control requirements and date by which attainment is to be 
achieved vary with an area's classification. Marginal areas were 
subject to the fewest mandated control requirements and had the 
earliest attainment date, November 15, 1993. Severe and extreme areas 
are subject to more stringent planning requirements but are provided 
more time to attain the standard. Serious areas were required to attain 
the 1-hour standard by November 15, 1999, and severe areas are required 
to attain by November 15, 2005, or November 15, 2007, depending on each 
area's ozone design value for the period from 1987 through 1989. The 
Baton Rouge area was classified as serious and its attainment date was 
November 15, 1999. The Baton Rouge area encompasses East Baton Rouge, 
West Baton Rouge, Ascension, Iberville, and Livingston Parishes (40 CFR 
81.319).
    The requirements of the Act for ozone attainment demonstrations for 
serious ozone nonattainment areas are specified in several sections of 
the Act. Section 182(c) sets forth the requirements for serious areas. 
Section 172(c)(6) of the Act requires all nonattainment area SIPs to 
include enforceable emission limitations, and such other control 
measures, means or techniques as well as schedules and timetables for 
compliance, as may be necessary or appropriate to provide for 
attainment by the applicable attainment date. Section 172(c)(1) 
requires the implementation of all reasonably available control 
measures (including, at a minimum, Reasonably Available Control 
Technology (RACT)) and requires the SIP to provide for attainment of 
the NAAQS. Section 182(c) incorporates Section 182(b)(1)(A) and 
requires the SIP for serious areas to provide for reductions in 
emissions of VOC and NOX from the baseline emissions of at 
least 3 percent averaged over each consecutive 3-year period until the 
applicable attainment date. Finally, section 182(c)(2)(A) requires the 
use of photochemical grid modeling or other methods judged to be at 
least as effective to demonstrate attainment of the ozone NAAQS by the 
applicable attainment date. EPA's ``General Preamble for the 
Implementation of Title I of the Clean Air Act Amendments of 1990'' (57 
FR 13498, April 16, 1992) provides the interpretative basis for EPA's 
rulemakings under the nonattainment plan provisions of the Act 
(hereinafter referred to as the General Preamble). As part of today's 
proposal, EPA is proposing action on the attainment demonstration SIP 
revisions submitted by the State of Louisiana for the Baton Rouge area 
and its associated ozone modeling domain. See Section I.B. below.
    In general, an attainment demonstration SIP includes a modeling 
analysis showing how an area will achieve the standard by its 
attainment date and the emission control measures

[[Page 50393]]

necessary to achieve attainment. The attainment demonstration SIPs must 
include motor vehicle emission budgets for transportation conformity 
purposes. Transportation conformity is a process required by Section 
176(c) of the Act for ensuring that emissions from all on-road sources 
are consistent with the attainment of the standard. Ozone attainment 
demonstrations must include the estimates of motor vehicle VOC and 
NOX emissions that are consistent with attainment, which 
then act as a budget or ceiling for the purposes of determining whether 
transportation plans, programs, and projects conform to the attainment 
SIP. Refer to Section II.A.4. for more details.
What Is the History and Time Frame for the State Attainment 
Demonstration SIP?
    On May 10, 2000, the Governor of Louisiana requested an attainment 
date extension for the Baton Rouge area. On May 9, 2001, EPA proposed 
its finding that the Baton Rouge area did not attain the 1-hour ozone 
NAAQS by the applicable attainment date (66 FR 23646). The proposed 
finding was based upon ambient air quality data from the years 1997, 
1998, 1999. These data show that the 1-hour ozone NAAQS of 0.12 parts 
per million (ppm) was exceeded on an average of more than one day per 
year over this three-year period. Furthermore, the area did not qualify 
for an attainment date extension under section 181(a)(5) as the area 
had more than 1 exceedance of the 1-hour standard in 1999. EPA also 
proposed that the appropriate reclassification of the area was too 
severe.
    In that proposed action, we also stated that Louisiana was seeking 
an extension of its attainment date pursuant to EPA's July 16, 1998, 
guidance memorandum entitled ``Extension of Attainment Dates for 
Downwind Transport Areas,'' published in a March 25, 1999, Federal 
Register notice (64 FR 14441) (hereinafter referred to as EPA's 
extension policy). EPA's extension policy includes EPA's interpretation 
of the Act regarding the extension of attainment dates for ozone 
nonattainment areas that have been classified as moderate or serious 
for the 1-hour ozone standard and which are downwind of areas that have 
interfered with their ability to demonstrate attainment of the ozone 
standard by dates prescribed in the Act.
    EPA proposed to take final action on the determination of 
nonattainment and reclassification of the Baton Rouge area only after 
the area had received an opportunity to qualify for an attainment date 
extension under the extension policy. Louisiana submitted an Attainment 
Plan/Transport SIP on December 31, 2001, for the Baton Rouge area. EPA 
was in the process of reviewing the Attainment Plan/Transport SIP when 
the United States District Court for the Middle District of Louisiana 
entered a Judgment on March 7, 2002, ordering EPA to determine, by June 
5, 2002, whether the Baton Rouge area had attained the applicable ozone 
standard under the CAA. LEAN v. Whitman, No. 00-879-A. In compliance 
with Court's Order, on June 24, 2002, (67 FR 42688) we published in the 
Federal Register our determination that the Baton Rouge area did not 
attain the 1-hour ozone standard by November 15, 1999. By operation of 
law, that determination results in the Baton Rouge area being 
reclassified from a serious to a severe nonattainment area on the 
effective date of that rule. EPA concurrently proposed to extend the 
effective date of our determination from August 23, 2002, to October 4, 
2002 (67 FR 42697, June 24, 2002). In the June 24, 2002, proposed 
rulemaking, EPA also set forth its intent to withdraw the final 
determination and reclassification, if EPA granted the State an 
attainment date extension before the effective date of the 
determination and reclassification rule.
What Is the Time Frame for Taking Action on the Attainment 
Demonstration SIPs?
    Louisiana submitted the attainment demonstration SIP revisions and 
supporting documentation between December 2001 and July 2002. EPA 
believes that it is important to keep the process moving forward in 
evaluating these plans and, as appropriate, approving them. In today's 
Federal Register, EPA is proposing to approve the Attainment 
Demonstration SIP. EPA is taking separate actions on other related 
revisions to the Baton Rouge SIP, including the Inspection and 
Maintenance Program (67 FR 44410, July 2, 2002), NOX 
regulations (67 FR 30638, May 7, 2002, and 67 FR 48095, July 23, 2002), 
New Source Review (see 67 FR 48090, July 23, 2002), emissions 
reductions credit banking (see 67 FR 48083, July 23, 2002), Contingency 
Measures (see 67 FR 35468, May 20, 2002), and SIP revisions dealing 
with VOC emissions from industrial wastewater (67 FR 41840, June 20, 
2002). EPA will not take final action to approve the attainment 
demonstration and extension of the attainment data unless and until it 
completes action on all other required rules.
    The anticipated schedule for actions on the State's submittals has 
been set forth in a recent proposed rulemaking June 24, 2002, (67 FR 
42697). EPA intends to complete rulemaking on the attainment 
demonstration and attainment date extension for the Baton Rouge area 
after it completes action on the submittals from Louisiana of the 
additional measures necessary to support the attainment demonstration 
and necessary to address the criteria of the extension policy. Provided 
EPA has taken final action on all other required rules, EPA plans to 
send a notice of final rulemaking on the attainment demonstration and 
attainment date extension to the Office of the Federal Register no 
later than October 4, 2002, for publication.
What Action Is EPA Proposing Regarding the Determination of 
Nonattainment as of November 15, 1999, and Reclassification Published 
on June 24, 2002?
    EPA is here proposing to withdraw the June 24, 2002, Notice of 
Nonattainment and Reclassification, if EPA issues a final rulemaking 
granting an attainment date extension prior to the effective date of 
the Notice of Nonattainment. EPA believes this is appropriate for a 
number of reasons. Section 181(b)(2)(A) of the Act requires that EPA 
determine attainment within six months of the attainment date. If the 
attainment date were extended, there would be a new deadline for the 
determination. See section I.D. below. Thus if the attainment date were 
extended, EPA's obligation to determine attainment would not yet have 
occurred and EPA could withdraw the published nonattainment 
determination and the consequent reclassification, which would not yet 
have gone into effect. Such a course would harmonize the need to allow 
the Agency to fulfill its duty to take into account upwind transport, 
while adhering to a fixed and very near-term schedule. See EPA's 
rulemaking in St. Louis, Missouri, 66 FR 33995 (June 26, 2001). See 
also EPA's recent granting of an attainment date extension in Atlanta, 
Georgia. 67 FR 30,574 (May 7, 2002).
    On July 2, 2002, the U.S. Court of Appeals for the District of 
Columbia vacated EPA's approval of an attainment date extension for the 
Washington, DC ozone nonattainment area. Sierra Club v. EPA, Nos. 01-
1070 and 01-1158 (D.C. Cir., 2002). EPA is currently evaluating this 
decision and considering what impact it may have on EPA's future 
actions concerning the Baton Rouge area.

[[Page 50394]]

B. Components of a Modeled Attainment Demonstration

    EPA provides guidance (GUIDELINE FOR REGULATORY APPLICATION OF THE 
URBAN AIRSHED MODEL, July 1991; Guidance on the Use of Modeled Results 
to Demonstrate Attainment of the Ozone NAAQS, EPA-454/B-95-007, June 
1996; and Guidance for Improving Weight of Evidence Through 
Identification of Additional Emission Reductions, Not Modeled, November 
1999) to which States may refer when developing a modeled attainment 
demonstration and supplementing it with additional evidence to 
demonstrate attainment. To have a complete modeling demonstration 
submission, States should have submitted the modeling analyses and 
identified any additional evidence that EPA should consider in 
evaluating whether the area will attain the standard. Additional 
components are discussed below.
What EPA Guidelines Apply to the Attainment Demonstration Submittals?
    The following documents, among others, contain EPA's guidelines 
affecting the content and review of ozone attainment demonstration 
submittals:
    1. Guideline for Regulatory Application of the Urban Airshed Model, 
EPA-450/4-91-013, July 1991. Web site: http://www.epa.gov/ttn/scram/ 
(file name: ``UAMREG'').
    2. Memorandum, ``The Ozone Attainment Test in State Implementation 
Plan (SIP) Modeling Demonstrations,'' from Joseph A. Tikvart, Office of 
Air Quality Planning and Standards, December 16, 1992.
    3. Guidance on Urban Airshed Model (UAM) Reporting Requirements for 
Attainment Demonstrations, EPA-454/R-93-056, March 1994. Web site: 
http://www.epa.gov/ttn/scram/ (file name: ``UAMRPTRQ'').
    4. Memorandum, ``Ozone Attainment Demonstrations,'' from Mary D. 
Nichols, Assistant Administrator for Air and Radiation, March 2, 1995. 
Web site: http://www.epa.gov/ttn/oarpg/t1pgm.html.
    5. Guidance on the Use of Modeled Results to Demonstrate Attainment 
of the Ozone NAAQS, EPA-454/B-95-007, June 1996. Web site: http://www.epa.gov/ttn/scram/ (file name: ``O3TEST'').
    6. Memorandum, ``Guidance for Implementing the 1-Hour Ozone and 
Pre-Existing PM10 NAAQS,'' from Richard Wilson, Office of Air and 
Radiation, December 29, 1997. Web site: http://www.epa.gov/ttn/oarpg/t1pgm.html.
    7. Memorandum, ``Extension of Attainment Dates for Downwind 
Transport Areas,'' from Richard D. Wilson, Acting Assistant 
Administrator for Air and Radiation, July 16, 1998.
    8. Memorandum, ``Guidance on Motor Vehicle Emissions Budgets in 
One-Hour Ozone Attainment Demonstrations,'' from Merrylin Zaw-Mon, 
Acting Director of the Regional and State Programs Division, November 
3, 1999. Web site: http://www.epa.gov/ttn/oarpg/t1pgm.html.
    9. Memorandum, ``Guidance on the Reasonably Available Control 
Measures (RACM) Requirement and Attainment Demonstration Submissions 
for Ozone Nonattainment Areas,'' from John S. Seitz, Director of Office 
of Air Quality Planning and Standards, November 30, 1999.
    10. Guidance for Improving Weight of Evidence Through 
Identification of Additional Emission Reductions, Not Modeled, Office 
of Air Quality Planning and Standards, November 1999. Web site: http://www.epa.gov/ttn/scram/ (file name: ``ADDWOE1H'');
    11. Procedures for Emission Inventory Preparation, Volume IV: 
Mobile Sources (Revised) (1992);
    12. User's Guide to MOBILE5 (Mobile Source Emission Factor Model), 
May 1994;
    13. Memorandum, ``Ozone Attainment Dates for Areas Affected by 
Overwhelming Transport,'' from Mary D. Nichols, Assistant Administrator 
for Air and Radiation, Environmental Protection Agency, September 1994.
What Are the Modeling Requirements for the Attainment Demonstration?
    For purposes of demonstrating attainment, the Act requires States 
containing serious or above ozone nonattainment areas to use 
photochemical grid modeling or an analytical method judged by EPA to be 
at least as effective. The photochemical grid model is set up using 
meteorological conditions conducive to the formation of ozone in the 
nonattainment area and its modeling domain. Emissions for a base year 
are used to evaluate the model's ability to reproduce actual monitored 
air quality values. Following validation of the modeling system for a 
base year, emissions are projected to an attainment year to predict air 
quality changes in the attainment year due to the emission changes, 
which include growth up to and controls implemented by the attainment 
year. A modeling domain is chosen that encompasses the nonattainment 
area. Attainment is demonstrated when all predicted ozone 
concentrations inside the modeling domain are at or below the ozone 
standard or an acceptable upper limit above the standard under certain 
conditions provided in EPA's guidance. When the predicted 
concentrations are above the standard or upper limit, EPA guidance 
provides for the use of an optional weight-of-evidence determination 
which incorporates other analyses, such as air quality and emissions 
trends, to address uncertainty inherent in the application of 
photochemical grid models. This latter approach may be used under 
certain circumstances to support the demonstration of attainment.
    EPA guidance identifies the features of a modeling analysis that 
are essential to obtain credible results. First, the State develops and 
implements a modeling protocol. The modeling protocol describes the 
methods and procedures to be used in conducting the modeling analyses 
and provides for policy oversight and technical review by individuals 
responsible for developing or assessing the attainment demonstration 
(State and local agencies, EPA, the regulated community, and public 
interest groups). Second, for purposes of developing the information to 
put into the model, the State selects air pollution days, i.e., days in 
the past with high ozone concentrations exceeding the standard, that 
are representative of the ozone pollution problem for the nonattainment 
area. Third, the State identifies the appropriate dimensions of the 
area to be modeled, i.e., the modeling domain size. The domain should 
be larger than the designated nonattainment area to reduce uncertainty 
in the boundary conditions and should include any large upwind sources 
just outside the nonattainment area. In general, the domain is 
considered the local area where control measures are most beneficial to 
bring the area into attainment. Alternatively, a much larger modeling 
domain may be established, addressing the impacts of both local and 
regional emission control measures on a number of ozone nonattainment 
areas. In both cases, the attainment determination is based on the 
review of ozone predictions within the local area where control 
measures are most beneficial to bring the area into attainment 
(referred to as the local modeling domain). Fourth, the State 
determines the grid resolution. The horizontal and vertical resolutions 
in the model can significantly affect the modeled results of dispersion 
and transport of emission plumes. Artificially large grid cells (too 
few vertical layers and horizontal grids) may dilute concentrations and 
may not

[[Page 50395]]

properly consider impacts of complex terrain, complex meteorology, and 
land/water interfaces. Fifth, the State generates meteorological and 
emissions data that describe atmospheric conditions and emissions 
inputs reflective of the selected high ozone days. Finally, the State 
verifies that the modeling system is properly simulating the chemistry 
and atmospheric conditions through diagnostic analyses and model 
performance tests (generally referred to as model validation). Once 
these steps are satisfactorily completed, the model is ready to be used 
to generate air quality estimates to support an attainment 
demonstration.
    The modeled attainment test compares model predicted 1-hour daily 
maximum ozone concentrations in all grid cells for the attainment year 
to the level of the ozone standard. A predicted peak ozone 
concentration above 0.124 ppm (124 ppb) indicates that the area is 
expected to exceed the standard in the attainment year. This type of 
test is often referred to as an exceedance test. EPA's June 1996 
guidance recommends that States use either of two exceedance tests for 
the 1-hour ozone standard: a deterministic test or a statistical test.
    Under the deterministic test, the State compares predicted 1-hour 
daily maximum ozone concentrations for each modeled day \1\ to the 
attainment level of 0.124 ppm. If none of the predictions exceed 0.124 
ppm, the test is passed.
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    \1\ The initial, ``ramp-up'' days for each episode are excluded 
from this determination.
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    The statistical test takes into account the fact that the form of 
the 1-hour ozone standard allows exceedances. If, over a 3 year period, 
the area has an average of 1 or fewer ozone standard exceedances per 
year at any monitoring site, the area is not violating the standard. 
Thus, if the State models a severe day (considering meteorological 
conditions that are very conducive to high ozone levels and that should 
lead to fewer than 1 exceedance per year at any location in the 
nonattainment area and in the modeling domain over a 3 year period), 
the statistical test provides that a prediction above 0.124 ppm up to a 
certain upper limit may be consistent with attainment of the standard.
    The acceptable upper limit above 0.124 ppm is determined by 
examining the size of exceedances at monitoring sites which meet or 
attain the 1-hour standard. For example, a monitoring site for which 
the 4 highest 1-hour average concentrations over a 3 year period are 
0.136 ppm, 0.130 ppm, 0.128 ppm, and 0.122 ppm is attaining the 
standard. To identify an acceptable upper limit, the statistical 
likelihood of observing ozone air quality exceedances of the standard 
of various concentrations is equated to the severity of the modeled 
day. The upper limit generally represents the maximum ozone 
concentration level observed at a location on a single day and it would 
be the only reading above that standard that would be expected to occur 
no more than an average of once a year over a 3 year period. Therefore, 
if the maximum ozone concentration predicted by the model is below the 
acceptable upper limit, in this case 0.136 ppm, then EPA might conclude 
that the modeled attainment test is passed. Generally, exceedances well 
above 0.124 ppm are very unusual at monitoring sites meeting the 
standard. Thus, these upper limits are rarely significantly higher than 
the attainment level of 0.124 ppm.
What Are the Additional Analyses That May Be Considered When the 
Modeling Fails To Show Attainment?
    When the modeling does not conclusively demonstrate that the area 
will attain, additional analyses may be presented to help determine 
whether the area will attain the standard. As with other predictive 
tools, there are inherent uncertainties associated with modeling and 
its results. For example, there are uncertainties in some of the 
modeling inputs, such as the meteorological and emissions data bases 
for individual days and in the methodology used to assess the severity 
of an exceedance at individual sites. EPA's guidance recognizes these 
limitations and provides a means for considering other evidence to help 
assess whether attainment of the standard is likely. The process by 
which this is done is called a weight-of-evidence determination.
    Under a weight-of-evidence determination, the State can rely on and 
EPA will consider factors such as: model performance and results, 
episode selection, other modeled attainment tests, e.g., relative 
reduction factor analysis; other modeled outputs, e.g., changes in the 
predicted frequency and pervasiveness of exceedances and predicted 
changes in the design value; actual observed air quality trends; 
estimated emission trends; analyses of air quality monitored data; the 
responsiveness of the model predictions to further controls; and, 
whether there are additional control measures that are or will be 
approved into the SIP but were not included in the modeling analysis. 
This list is not an exhaustive list of factors that may be considered 
and these factors could vary from case to case. EPA's guidance contains 
no limit on how close a modeled attainment test must be to passing to 
conclude that other evidence besides a modeled attainment test is a 
sufficiently compelling case for attainment. However, the further a 
modeled attainment test is from being passed, the more compelling the 
weight-of-evidence needs to be.

C. Framework for Proposing Action on the Attainment Demonstration SIP

    In addition to the modeling analysis and weight-of-evidence 
determination demonstrating attainment, EPA has identified the 
following key elements which must be present in order for EPA to 
approve the 1-hour attainment demonstration SIP.
1. Clean Air Act Measures and Other Measures Relied on in the 
Attainment Demonstration State Implementation Plan
    The attainment demonstration must incorporate the emission impacts 
of any emission control measures needed to achieve attainment. The 
rules for these emission controls must also have been adopted by the 
State and approved by EPA as part of the SIP no later than the time EPA 
finally approves the attainment demonstration. The emission controls 
for these sources must be implemented as expeditiously as practicable 
but not later than the applicable attainment date.
    For purposes of fully approving the State's attainment 
demonstration SIP, the State must adopt and submit all VOC and 
NOX control regulations for affected sources within the 
State and within the local modeling domain as reflected in the adopted 
emission control strategy and as reflected in the attainment 
demonstration.
    The measures required for serious ozone nonattainment areas by 
section 182(c) of the CAA include: (1) Attainment and reasonable 
further progress demonstrations; (2) enhanced vehicle inspection and 
maintenance 
(I/M) programs; (3) clean-fuel vehicle programs; (4) RACT for VOC and 
NOX; (5) New Source Review (NSR) regulations for VOC and 
NOX, including an offset ratio of 1.2:1 and a major VOC and 
NOX source size cutoff of 50 tons per year (TPY); (6) an 
enhanced air monitoring program; and (7) contingency provisions. These 
requirements are specified in sections 182(c) and 182(f) of the Act.
    To receive an extension of the attainment date, under the extension 
policy, the State must have adopted the emission control measures 
required under the Act for the area's classification or must have 
established negative declarations for the source

[[Page 50396]]

categories for which the area has no major sources that are subject to 
Clean Air Act requirements.
2. Motor Vehicle Emissions Budget
    An attainment demonstration SIP must estimate the motor vehicle 
emissions that will be produced in the attainment year and must 
demonstrate that this emissions level, when considered with emissions 
from all other sources, is consistent with attainment. Generally when a 
state makes an initial SIP submittal, EPA conducts an expedited review, 
including an opportunity for public comment, to determine if the 
submitted budgets meet the adequacy criteria contained in the 
transportation conformity rule (40 CFR 93.118). A motor vehicle 
emissions budget contained in an initial SIP submittal cannot be used 
to determine the conformity of the transportation plans and programs to 
the SIP, as required by section 176(c) of the Act, until it is found 
adequate. EPA then conducts a review of the entire SIP submittal to 
determine if the SIP, including the attainment motor vehicle emissions 
budgets, can be approved. An appropriately identified motor vehicle 
emissions budget is a necessary part of an attainment SIP.

D. Criteria for Attainment Date Extensions

What Is EPA's Policy With Regard to an Ozone Attainment Date Extension?
    EPA's policy regarding an extension of the ozone attainment date 
for the Baton Rouge area is addressed in EPA's notice of proposed 
rulemaking dated May 9, 2001. 66 FR 23646. In the May 9, 2001, 
document, EPA proposed to reclassify the Baton Rouge area to a severe 
ozone nonattainment area, but also provided notice of the area's 
potential eligibility for an attainment date extension based on the 
July 16, 1998 EPA guidance memorandum. In today's document, EPA 
proposes to approve the State's request for an attainment date 
extension under that policy provided that EPA issues a final approval 
of the State's attainment demonstration and any other required local 
measures. The specifics of the attainment date policy are repeated 
below for clarity.
    That memorandum stated that EPA will consider extending the 
attainment date for an area or a State that:
    (1) Has been identified as a downwind area affected by transport 
from either an upwind area in the same State with a later attainment 
date or an upwind area in another State that significantly contributes 
to downwind ozone nonattainment;
    (2) Has submitted an approvable attainment demonstration with any 
necessary, adopted local measures and with an attainment date that 
shows it will attain the 1-hour standard no later than the date that 
the emission reductions are expected from upwind areas under the final 
NOX SIP call (by 2003) and/or the statutory attainment date 
for upwind nonattainment areas, i.e., assuming the boundary conditions 
reflecting those upwind emission reductions;
    (3) Has adopted all applicable local measures required under the 
area's current ozone classification and any additional emission control 
measures demonstrated to be necessary to achieve attainment, assuming 
the emission reductions occur as required in the upwind areas; and
    (4) Has provided that it will implement all adopted measures as 
expeditiously as practicable, but no later than the date by which the 
upwind reductions needed for attainment will be achieved.
    Once an area receives an extension of its attainment date based on 
ozone/precursor transport impacts, the area would no longer be subject 
to reclassification to a higher ozone nonattainment classification. If 
the Baton Rouge area is granted an attainment date extension, it would 
no longer be subject to a reclassification to severe nonattainment for 
ozone and no longer subject to the additional emission control 
requirements that would result from the reclassification to severe 
nonattainment.
    Louisiana has requested an extension of the attainment date for the 
Baton Rouge area in conjunction with the ozone attainment demonstration 
submittals. The ozone attainment demonstration uses November 15, 2005, 
as the appropriate ozone attainment date. EPA is proposing to extend 
the attainment date for the Baton Rouge area to November 15, 2005, if 
EPA takes final action to approve the attainment demonstration and any 
other required local measures. For a discussion of how the Baton Rouge 
area satisfies the criteria for the attainment date extension, see 
section II.D. below.

II. Technical Review of the Submittals

A. Summary of the State Submittals

1. General Information
When Were the Ozone Attainment Demonstration State Implementation Plan 
Revisions Submitted to the Environmental Protection Agency?
    Louisiana has made the following submittals, which in whole or in 
part concern the ozone attainment demonstration and an extension of the 
attainment date for the Baton Rouge area:
    (a) On December 31, 2001, LDEQ submitted an ozone attainment 
demonstration and transport SIP revision. The SIP revision included:
    i. A revision to the 15% ROPP for the control of VOC emissions in 
the Baton Rouge area. The 15% Rate ROPP was approved by EPA on October 
22, 1996 (61 FR 54737).
    ii. Revisions to the 1990 base year emissions inventory. The 
inventory was approved on July 2, 1999 (64 FR 35930).
    iii. Revisions to the Post-1996 ROPP. The Post-1996 ROPP was 
approved on July 2, 1999 (64 FR 35930).
    iv. Revisions to the I/M program.
    v. Attainment MVEBs for 2005 for VOCs and NOX.
    vi. An enforceable commitment to submit revised MVEBs within 24 
months after the release of MOBILE6.
    vii. An enforceable commitment for mid-course review.
    viii. An enforceable transportation control measure referred to as 
the Advanced Transportation Management System.
    ix. An emissions control strategy that incorporates federal, state, 
and local control measures.
    x. Revisions to Louisiana's New Source Review rules.
    (b) On February 1, 2002, LDEQ submitted the changes to the proposed 
rule for the control of NOX emissions.
    (c) On February 27, 2002, LDEQ submitted final rules for the 
emission reductions credit banking program and for the control of 
NOX emissions.
    (d) On February 27, 2002, LDEQ also submitted final revisions to 
the contingency measures proposed in the December 31, 2002, SIP 
submittal.
    (e) On April 8, 2002, LDEQ submitted a letter requesting parallel 
processing of revisions to the State's NOX regulations.
    (f) On May 20, 2002, LDEQ submitted a letter concerning the 
revisions to the rulemaking dealing with VOC emissions from industrial 
wastewater.
    EPA is taking separate actions on certain revisions to the Baton 
Rouge SIP, including the Inspection and Maintenance Program (67 FR 
44410,

[[Page 50397]]

July 2, 2002), NOX regulations (67 FR 30638, May 7, 2002, 
and 67 FR 48095, July 23, 2002), New Source Review (see 67 FR 48090, 
July 23, 2002), emissions reductions credit banking (see 67 FR 48083, 
July 23, 2002), Contingency Measures (see 67 FR 35468, May 20, 2002), 
and SIP revisions dealing with VOC emissions from industrial wastewater 
(67 FR 41840, June 20, 2002). In this proposed rulemaking the following 
are considered: the ozone attainment demonstration plan and its 
associated MVEBs; the transport SIP related materials; the RACM 
analysis; and the revisions to the 1990 base year inventory, the 15% 
ROPP, and the Post-1996 ROPP.
When Was the Submittal Addressed in a Public Hearing, and When Was the 
Submittal Formally Adopted by the State?
    LDEQ held a public hearing on the attainment plan and transport SIP 
on November 26, 2001, and adopted it on December 27, 2001.
2. Modeling Procedures, Input Data, and Results
What Modeling Approach Was Used in the Analyses?
    The attainment modeling approach is documented in Louisiana's 
December 31, 2001, ozone attainment demonstration SIP and information 
Louisiana previously submitted to EPA on May 10, 2000. EPA's technical 
analysis discussed later in this document is based on data from this 
modeling domain. For additional information, see the Technical Support 
Document (TSD) and the State's submittal.
    Besides being able to model ozone and other pollutants in nested 
horizontal grids, the UAM-V photochemical model (used by LDEQ) can also 
model individual elevated source plumes within the modeling grid. 
Gaussian dispersion models are used to grow plumes until the plumes 
essentially fill grid cells. At these points, the numerical dispersion 
and advection components of UAM take over to address further downwind 
dispersion and advection.
    The following input data systems and analyses were also used as 
part of the combined modeling system:
    Emissions: UAM-V requires the input of an emissions inventory of 
gridded, hourly estimates of CO, NOX, and speciated VOC 
emissions (speciated based on carbon bond types). The State provided 
regional and local emission inventories, which were processed through 
the Emissions Preprocessor System, Version 2.5 (EPS-2.5) to prepare 
UAM-V emissions data input files.
    Louisiana has also made changes to the 1996 emission inventory as 
documented in the December 31, 2001, submittal. The State submittals 
describe in detail the procedures used to develop, and then project, 
the base year emission inventories to the 1997/1999 period and to 
project emissions to account for growth and control through November 
15, 2005.
What High Ozone Periods Were Selected for the Modeling Demonstration?
    EPA's Guideline sets forth a recommended procedure for selecting 
ozone exceedance episodes appropriate for conducting a modeling 
demonstration. This procedure, in part, considers wind rose analyses 
based upon the four morning hours of 0700 to 1000 standard time. LDEQ's 
episode selection for the Baton Rouge 1-hour ozone modeling analysis 
was based on a review of historical meteorological and air quality 
data, and application of a procedure for optimizing representation of 
the key meteorological regimes. The results for 1-hour ozone for Baton 
Rouge overlap with the Gulf Coast Ozone Study (GCOS) modeling episodes 
for two of the four GCOS episode periods. The Baton Rouge 1-hour ozone 
modeling analysis also includes a third episode that is not a part of 
the GCOS study. The selected episode periods were:

a. August 24-31, 1997 (Sunday-Sunday)
b. September 10-18, 1997 (Wednesday-Thursday)
c. August 1-8, 1999 (Sunday-Sunday)

    With respect to the considerations listed above, the three episode 
periods included:
    a. Six 1-hour exceedance days that represent five different types 
of meteorological regimes.
    b. Eleven days with ozone concentrations within 10 ppb of the 
design value for Baton Rouge (these include several days that represent 
the three most frequently occurring exceedance meteorological regimes).
    c. A range of ozone concentrations among the 1-hour exceedance days 
from 126 to 143 ppb (with a mean of 131 ppb).
    Based on observed ozone concentrations and meteorological 
conditions, and considering the EPA guidance procedures, LDEQ chose 
September 13, 1997, August 31, 1997, and August 7, 1999 as the three 
primary episode days for the Baton Rouge 1-hour ozone modeling 
analysis.
    For the September 1997 episode period, September 13 is a key 
exceedance day with a maximum ozone concentration near the 1997-1999 
design value (126 ppb) and meteorological conditions representative of 
a key exceedance meteorological regime (the ``continental high'' 
regime). Wind directions (near the surface and aloft) are primarily 
from the north.
    For the August 1997 episode period, August 31 is the only 
exceedance day (with a peak of 127 ppb) and the key episode day. 
Meteorological conditions transition from a key exceedance 
meteorological regime (the ``gulf high'' regime) to a disturbance 
regime during this day. Light and variable winds are associated with a 
high-pressure system that is located over Baton Rouge on the 31st and 
the local conditions reflect the influence of high pressure.
    For the August 1999 episode period, the 7th stands out as the best 
day for use in the attainment demonstration. This is due to high ozone 
and, partially, representative meteorological conditions. It also 
complements the other key days (from the August and September 1997 
episode periods) with southerly to southeasterly winds (with this day, 
the key three episode days combined include northerly, southerly, and 
light and variable wind components). The maximum ozone concentration 
(143 ppb) is more than 10 ppb greater than the design values for 1997-
1999 and 1999-2001.
What Procedures and Sources of Projection Data Were Used To Project the 
Emissions to Future Years?
    The 2005 future-year basecase episode incorporates the effects of 
population and industry growth (or, in some cases, decline) as well as 
national and statewide control measures or programs that should be in 
place by 2005. The future-year basecase emissions inventory is based on 
typical summer day emissions, with adjustments for source-specific and 
episode-specific information. Growth and control factors (for the 
entire modeling domain) were obtained from the Bureau of Economic 
Analysis (BEA) and applied based on 2-digit Standard Industrial Code 
(SIC) for point sources and on the EPS 2.5 default projection factor 
assignments by source category code for area and mobile sources. 
Employment was used as the basis for the growth factors for Louisiana. 
The control factors represent reductions in emissions that should occur 
as a result of required control requirements. The 2005 basecase 
emissions inventory also incorporates the expected emission reductions

[[Page 50398]]

associated with EPA's NOX SIP Call and Tier II vehicle 
standards and fuel sulfur program, as well as emissions reductions 
associated with the 2007 SIPs for the Houston/Galveston and Beaumont/
Port Arthur, Texas, areas. For the Baton Rouge subdomain (Grid D), 
projection of the emissions to 2005 resulted (approximately) in a one 
percent increase in NOX emissions and a corresponding 15 
percent decrease in VOC emissions compared to the base year (1997/
1999). The offshore area and point sources were projected to 2005 using 
the information provided by Mineral Management Services (MMS) 
reflecting expected future activity. The offshore oil platforms were 
modeled as point sources, and other source categories were modeled as 
area sources. Details of the above methods are discussed further in the 
TSD and Louisiana's submittals.
How Did the State Validate the Photochemical Modeling Results?
    The LDEQ SIP modeling analysis included the application of the UAM-
V modeling system for basecase year episode periods and a future year 
of 2005. LDEQ selected three basecase episodes for this attainment 
demonstration modeling. They were the August 24-31, 1997, September 10-
18, 1997 and August 1-8, 1999 episodes. Model performance evaluations 
were conducted for each of these episodes.
    Model performance evaluation based upon diagnostic and sensitivity 
analyses consisted of testing the response of modeled ozone to changes 
in the various model inputs (i.e., meteorology, emission inventory, and 
initial & boundary conditions). The model performance evaluation based 
upon graphical measures consisted of comparing time series of monitored 
and modeled ozone and ozone precursor concentrations, and comparing 
modeled ozone concentration contours with monitored ozone data. The 
model performance evaluation based upon statistical measures consisted 
of comparing the modeled versus monitored ozone ``Unpaired Peak 
Accuracy'', ``Normalized Bias'', and ``Gross Error'' with EPA's 
recommended ranges for acceptable model performance. These evaluation 
methods and performance measurement analyses were utilized to pick 
representative ozone episode days for which the model could 
sufficiently replicate the episode day.
    The key simulation days for the Baton Rouge 1-hour ozone attainment 
demonstration are: September 13, 1997, August 31, 1997, and August 7, 
1999. These are exceedance days for which acceptable model performance 
was achieved. They also represent a range of meteorological conditions 
and, in particular, a variety of wind directions, which makes them 
especially suitable, in combination, for use in the attainment 
demonstration (i.e., a variety of wind directions and thus, potential 
source-receptor relationships are represented by the key modeling 
episode days). Further discussion of the choice of these days as the 
episode days is included in the individual episode discussions below. 
The 1-hour ozone attainment demonstration analysis presented focuses on 
these three primary episode days. The analysis of results for these 
days is supplemented by weight of evidence.
What Were the Ozone Modeling Results for the Base Period and for the 
Future Attainment Period?
    The basecase modeling analysis results indicate that the MM5/UAM-V 
modeling system can be used to successfully simulate the complex 
processes leading to high ozone in the Baton Rouge area, although in 
some cases it is difficult for the model to replicate site-specific 
details. Key findings related to model performance include:

--Model performance varies by day, and among the modeling episode 
periods.
--Statistical measures for Grid D are generally within the EPA 
recommended ranges.
--For the episodes modeled there is no consistent bias toward over- or 
under estimation on a domain-wide or site-specific basis.
--Gradients in the concentration fields, especially along the 
coastline, influence sites-specific model performance (especially when 
using the maximum values in the vicinity of sites to calculate the 
performance measures).
--Changes to the UAM-V inputs (emissions, meteorological, initial and 
boundary conditions) produce expected (and moderate) responses.

    The simulated high ozone concentrations for the three primary 
episode days occur in Baton Rouge (September 13, 1997), to the south of 
Baton Rouge (August 31, 1997), and to the northwest of Baton Rouge 
(August 7, 1999). From evaluation of meteorological conditions, these 
three primary episode days appear to represent the three key types of 
ozone episode meteorological patterns that typically occur in the Baton 
Rouge area. Because the meteorological conditions for August 7th 
represent a distinct wind pattern that is representative of ozone 
episodes, this episode day truly compliments the other two days. These 
three primary episode days represent the three key types of ozone 
episode meteorological patterns that typically occur in the Baton Rouge 
area. Acceptable basecase model performance is achieved that meets EPA 
statistical guidance for the two 1997 episode days. The August 7, 1999, 
episode day basecase modeling is slightly outside of EPA statistical 
guidance parameters, but can still be utilized to evaluate control 
strategy impacts based upon other evaluation techniques. Specifically, 
the 1999 episode day has generally good performance for sites within 
Baton Rouge and to the north of the urban area, but the simulated ozone 
profiles are flatter than observed at some of the outlying monitoring 
sites. The normalized bias value for August 7, 1999 is -16.8% (Grid D), 
which is just outside the preferred range of +/-15%. The Gross Tete 
monitoring site is one of the significant reasons the bias is off, and 
if this location were not included the bias would be within desired 
parameters. For further information concerning the Gross Tete 
monitoring site see the TSD.
Do the Modeling Results Demonstrate Attainment of the Ozone Standard?
    The modeling results for the Baton Rouge 5-parish nonattainment 
area were 123.4, 124.0, and 121.3 ppb for the three episode days. The 
maximum simulated ozone concentrations for Grid D (a rectangular area 
112 km  x  148 km that includes the Baton Rouge nonattainment area) 
were 123.4, 124.0, and 127.4 ppb. The 127.4 ppb peak is predicted to 
occur outside of the Baton Rouge nonattainment area for the 1999 
episode day. The two 1997 episode days demonstrated attainment 
utilizing the deterministic test. Therefore, Louisiana has demonstrated 
with these two episodes that the Baton Rouge nonattainment area will 
attain the standard by November 15, 2005. Since the 1999 episode does 
not meet the deterministic test because it predicts a level slightly 
above the standard occurring in an attainment parish outside of the 
Baton Rouge nonattainment area, to ensure that the chosen control 
strategy for the Baton Rouge nonattainment area will not cause an 
exceedance of the standard to occur in an attainment parish, Louisiana 
supplemented the attainment demonstration with weight-of-evidence. With 
weight-of-evidence for the 1999 episode, these modeling results 
indicate that the Baton Rouge nonattainment area will attain (and the 
surrounding area will continue to attain) the ozone

[[Page 50399]]

standard by November 15, 2005, with the proposed rules control scenario 
and other reductions occurring within the domain.
What Weight-of-Evidence Analyses and Determinations Are Used In This 
SIP?
    The modeling by itself does demonstrate attainment in the Baton 
Rouge nonattainment area, but the modeling for the 1999 episode day by 
itself does not conclusively demonstrate attainment in Grid D, an area 
outside the nonattainment area but downwind of it and within the State 
and part of the modeling domain. The modeling for both of the 1997 
episode days do show attainment within Grid D. The results for the 1999 
episode day, however, are close enough to warrant the consideration of 
weight of evidence arguments that support the modeling demonstration of 
attainment. EPA's guidance on the use of modeled results to demonstrate 
attainment of the ozone NAAQS (June, 1996) allows for the use of 
alternative analyses as weight-of-evidence. The alternative analyses 
should provide compelling evidence that a specific control strategy, 
even if it is not capable of demonstrating modeled attainment utilizing 
modeling, is nonetheless expected to achieve monitored attainment by 
the attainment date. In this case, the modeling does demonstrate 
attainment in the Baton Rouge nonattainment area and Grid D for the two 
1997 episodes, but weight of evidence provides additional support that 
is needed to determine that the attainment parishes within Grid D will 
stay in attainment for all three episode days (including the 1999 
episode day). The EPA's 1999 guidance document entitled ``Guidance for 
Improving Weight of Evidence Through Identification of Additional 
Emission Reductions, Not Modeled'' addressed additional weight-of-
evidence approaches, one of which considers methods that relate modeled 
ozone concentrations to monitored design values for a particular area.
    LDEQ's weight-of-evidence determination includes:
     Consideration of certain factors that are also the 
benchmarks for the statistical determination approach.
     Consideration of uncertainties associated with the 
modeling system.
     Application of relative-reduction procedures for 1-hour 
ozone on a site-specific basis (attainment and screening tests).
     Assessment of simulation results relative to 8-hour ozone.
     Application of relative-reduction procedures for 1-hour 
ozone on a domain-wide basis.
     Analysis of observed and simulated ozone trends.
    Using the statistical approach included in the 1996 guidance, 
Benchmark Test #1, which limits the number of exceedances within each 
subregion of the modeling domain according to the severity of the 
modeled primary episode days, is not met. One of the primary episode 
days (August 7, 1999) is characterized as severe, which is when the 
expected frequency of occurrence of the meteorological conditions 
associated with the episode is less than 2 times per year. The 
characterization of the episode determines the number of exceedances 
allowed using this method. The Grid D domain was divided into 
subregions, with each subregion containing 64 2-km grid cells, for this 
analysis. The number of allowable exceedances in each subregion is 
zero; for one subregion, one exceedance is simulated.
    Benchmark Test #2, which limits the extent to which the simulated 
concentrations for the severe primary episode days may exceed 124 ppb, 
is met. For the August 7, 1999 episode day, the maximum simulated value 
(Grid D) of 127.4 ppb is within the range of the estimated allowed 
maximum values of 124 to 129 ppb.
    Benchmark Test #3, provides that, for a composite of all primary 
episode days, the number of grid cell hours with simulated ozone 
concentrations greater than 124 ppb should be reduced by at least 80 
percent. The value of this parameter is reduced by 97.6 percent. This 
test is passed by a significant margin.
    The results from application of the statistical approach did not 
pass Benchmark Test #1. However, components of the statistical approach 
analyses do show improvements and thus this data can be used as one of 
the weight-of-evidence components.
    Additional weight of evidence was also considered. Uncertainties 
associated with modeling system were considered as part of the weight 
of evidence. Overestimation of the Baton Rouge nonattainment area 
domain-wide (Grid D) 1-hour maximum ozone concentration for the three 
episode days adds to the weight-of evidence that the results 
demonstrate attainment, since both the deterministic and (to a lesser 
extent) statistical methods for the 1-hour ozone attainment 
demonstration emphasize the reduction of the simulated peak 
concentration. The good model performance achieved for the September 
13, 1997, and August 31, 1997, primary episode days adds to the 
credibility of the attainment test results for these two days, which in 
both cases clearly indicate that attainment has been demonstrated 
(using both the deterministic and statistical methods). Poorer model 
performance for the August 7, 1999 episode supports use of greater 
caution in interpreting the results for this day than those for the 
other episode days. Additional weight-of-evidence is used to determine 
that the episode day demonstrates attainment.
    Despite the differences in simulated and observed ozone 
concentrations and model performance among the primary episode days, 
the response of the modeling system to the emission reductions is 
consistent among the simulation days, both on a percentage and absolute 
basis. The peak concentration for the attainment strategy simulation is 
reduced from that for the future year basecase simulation by 
approximately 7.5 percent for the September 13, 1997 and August 7, 1999 
simulation days and by approximately 10 percent for the August 31, 1997 
simulation day. The number of grid cell hours greater than 124 ppb and 
the value of the related 1-hour exceedance exposure metrics are about 
95 to 100 percent lower for the attainment strategy simulation. For the 
three primary episode days, separately and combined, the simulation 
results indicate emission reductions that comprise the attainment 
strategy are sufficient to bring the Baton Rouge area into attainment 
for three different but representative sets of meteorological 
conditions.
    Application of relative-reduction procedures for 1-hour ozone on a 
site-specific basis showed that for the simulated attainment strategy, 
the future-year estimated design value (EDV) for all sites is estimated 
to be less than 124 ppb (less than 120ppb) when the 1997-1999 design 
value is used for the calculation. Since the episodes modeled are from 
1997 and 1999, the 1997-1999 design values is considered to be the 
representative design values. LDEQ also performed analyses for two 
other design values periods as additional support. For the 1999-2001 
design values the future-year EDVs were all less than 120 ppb. When the 
1998-2000 design values are used for the calculation, the EDV for one 
site (LSU) is greater than 124 ppb and the EDV is less than 120 ppb for 
all the other sites. The EDV for the LSU site is 126.4 ppb. In summary, 
LDEQ utilized three different periods (1997-1999, 1998-2000, 1999-2001) 
for the starting design value of the Baton Rouge area. The relative-
reduction-factor (RRF) analysis yielded EDVs below 120 ppb for all 
three starting design values with the one exception. This exception was 
for one

[[Page 50400]]

monitor (LSU) and only occurred when one of the three latest design 
values were used. The application of the site-specific relative-
reduction method provides additional weight-of-evidence that the 
emission reductions associated with the attainment strategy will result 
in attainment of the 1-hour ozone standard by November 15, 2005. This 
method complements the traditional 1-hour attainment demonstration 
methods since the modeling results are used in a relative sense and 
some of the uncertainty associated with traditional 1-hour modeling is 
therefore avoided.
    The results of the site-specific relative-reduction attainment test 
for 8-hour ozone shows that the attainment-strategy emission reduction 
measures are also effective in reducing the 8-hour EDVs for all sites. 
For example, use of the 1997-1999 design values as the basis for the 
EDV calculation gives a reduction in the average (over all sites) 8-
hour design value from 88.1 to 81.4 ppb. The number of sites with 
design values greater than 84 ppb is reduced from ten (based on the 
1997-1999 design value) to four. While the details and schedule for 
implementation of 8-hour ozone standard and the associated attainment 
demonstration procedures are not fully known at this time, the modeling 
results indicate that the emission reductions associated with the 1-
hour attainment strategy will also significantly contribute to 
attainment of an 8-hour ozone standard for Baton Rouge.
    Application of relative-reduction procedures for 1-hour ozone on a 
domain-wide basis, gives an estimated design value for the Baton Rouge 
nonattainment area of 121.6 ppb. This additional weight-of-evidence 
test indicates that the attainment strategy will be sufficient to bring 
the area into attainment by November 15, 2005, and that further 
emission reductions are not required. Application of the domain-wide 
relative-reduction procedures provides additional strong support for 
the attainment strategy.
3. Emission Control Strategies
What Emission Control Strategies Were Considered in the Attainment 
Demonstration?
    Louisiana's emission control strategy relies on emission control 
requirements through 2005, including the impacts of the State's ROPPs 
for the Baton Rouge area, federal emission controls expected to be 
implemented before or by 2005, and the State's regional NOX 
emission limit.
    Louisiana has recently finalized regional NOX emission 
control regulations to cover this NOX limit. EPA has 
recently proposed approval of these regulations as meeting the RACT 
requirements of the Act. See 67 FR 48095, July 23, 2002. It should be 
noted that Louisiana has adopted NOX regulations for the 
Baton Rouge area and is no longer seeking an exemption from 
NOX RACT, NOX NSR, or NOX general 
conformity requirements. The modeling used to support the attainment 
demonstration does consider the impacts of NOX emission 
reductions resulting from NOX RACT implementation in the 
Baton Rouge area. EPA proposed to rescind the NOX exemptions 
for the Baton Rouge area under separate rulemaking actions. See 67 FR 
30638, May 7, 2002.
    The emission control strategy also considers the emission impacts 
of the following control measures: VOC emission reductions from 
implementation of RACT on various sources (see the discussion of the 
contents of Louisiana's December 31, 2001, submittal above); an 
improved vehicle I/M program; EPA's rulemakings for the National Low 
Emission Vehicle Program and the Tier 2 motor vehicle emissions 
standards and low sulfur gasoline program; and a TCM.
    The State included a TCM in its SIP as a control strategy for 
attainment of the 1-hour ozone NAAQS. The TCM is an Intelligent 
Transportation System (ITS) initiative which is locally referred to as 
the Advanced Transportation Management System (ATMS) facility and is 
described in detail in Chapter 4 and Appendix F of the State's SIP 
submittal. The SIP includes information about the project's 
description, implementation date, and emission reductions. This TCM 
will be incorporated by reference into the Code of Federal Regulations, 
if EPA takes final action to approve the attainment demonstration.
4. Motor Vehicle Emission Budgets
What Is a MVEB and Why Is It Important?
    The MVEB is the level of total allowable on-road emissions 
established by a control strategy implementation plan or maintenance 
plan. In this case, the MVEB establishes the maximum level of on-road 
emissions that can be produced in 2005, when considered with emissions 
from all other sources, which demonstrate attainment of the ozone 
NAAQS. It is important because the MVEB is used to determine the 
conformity of transportation plans and programs to the SIP, as 
described by section 176(c)(2)(A) of the Act.
What Are the MVEBs Established by This Plan and Proposed for Approval 
by This Action?
    On December 31, 2001, Louisiana submitted motor vehicle emissions 
budgets for the 2005 attainment year for the Baton Rouge area in their 
SIP. The attainment year MVEBs established by this plan that the EPA is 
proposing to approve are 15.48 tons per day for VOC and 34.26 tons per 
day for NOX for the Baton Rouge area. These budgets were 
posted on the EPA website for public comment. No comments were received 
and EPA has determined that the emissions budgets meet the adequacy 
requirements. We notified the State by letter of our determination on 
July 5, 2002, and notice of our determination was published on July 17, 
2002, (67 FR 46970) and is effective 15 days after that publication. In 
addition, we find the MVEBs consistent with all pertinent SIP 
requirements, and the MVEBs are proposed for approval as limited by the 
discussion below.
What Is the State's Commitment To Revise the MVEBs With MOBILE6?
    All States whose attainment demonstration includes the effects of 
the Tier 2/sulfur program have committed to revise and resubmit their 
MVEBs after we release MOBILE6. On December 31, 2001, the State 
submitted an enforceable commitment to perform new mobile source 
modeling for the Baton Rouge area, using MOBILE6, within 24 months of 
the model's official release. In addition, the enforceable commitment 
includes a provision stating that if a transportation conformity 
analysis is to be performed between 12 months and 24 months after the 
release of MOBILE6, transportation conformity will not be determined 
until the State submits an MVEB which is developed using MOBILE6 and 
which we find adequate. LDEQ informed the Capital Region Planning 
Commission (CRPC) and the Louisiana Department of Transportation and 
Development of these commitments, and that conformity cannot be 
determined during the second year until the MOBILE6-based budgets are 
submitted to EPA and found adequate.
    We are proposing that if we finalize this action, the current 
MOBILE5-based budgets will only be effective for conformity until 
revised motor vehicle emissions budgets are submitted and found 
adequate. We are proposing to limit the duration of our approval in 
this manner because we are only proposing to approve the attainment 
demonstration and the budgets because the State has committed to revise 
them

[[Page 50401]]

using MOBILE6. Therefore, if we confirm that the revised budgets are 
adequate, they will be more appropriate than the budgets we are 
proposing to approve today. Therefore we are proposing to approve the 
motor vehicle emission budgets and the enforceable commitment to submit 
revised budgets using MOBILE6 within 24 months after MOBILE6's release.
    If future changes to the budgets raise issues about the sufficiency 
of the attainment demonstration, we will work with the State. If the 
revised budgets show that motor vehicle emissions are lower than the 
budgets we approve, a reassessment of the attainment demonstration's 
analysis will be necessary.
    This action does not propose any change to the existing 
transportation conformity rule or to the way it is normally implemented 
with respect to other submitted and approved SIPs, which do not contain 
commitments to revise the budget.
    If the State fails to meet its commitment to submit revised budgets 
using MOBILE6, we could make a finding of failure to implement the SIP, 
which would start a sanctions clock under section 179 of the Act.
What Is the Applicable MVEB To Use for Conformity Analysis After 2005?
    When evaluating transportation plans and programs, emissions in 
years after 2005 must be less than the 2005 attainment MVEBs being 
proposed for approval here.
    We are proposing to approve the attainment MVEBs, pursuant to the 
State's commitments related to MOBILE6, only until revised MVEBs are 
submitted and we have found them adequate for transportation conformity 
purposes.
5. RACM Analysis and Determination of Availability
    Section 172(c)(1) of the Act requires SIPs to provide for the 
implementation of all RACM as expeditiously as practicable and for 
attainment of the standard. EPA has previously provided guidance 
interpreting the RACM requirements of 172(c)(1) in the General 
Preamble. See 57 FR 13498, 13560 (April 16, 1992). In the General 
Preamble, EPA indicated its interpretation of section 172(c)(1), under 
the 1990 Amendments, as imposing a duty on States to consider all 
available control measures and to adopt and implement such measures as 
are reasonably available for implementation in the particular 
nonattainment area. EPA also retained its pre-1990 interpretation of 
the RACM provisions, stating that we would not consider it reasonable 
to require implementation of measures that might in fact be available 
for implementation in the nonattainment area, but could not be 
implemented on a schedule that would advance the date for attainment in 
the area. EPA indicated that a State could reject certain measures as 
not reasonably available for various reasons related to local 
conditions. A State could include area-specific reasons for rejecting a 
measure as RACM such as, but not limited to, the rejected measure would 
not advance the attainment date, or would not be technologically or 
economically feasible for the area.
    The EPA also issued a recent memorandum reaffirming its position on 
this topic, ``Guidance on the Reasonably Available Control Measures 
(RACM) Requirement and Attainment Demonstration Submissions for Ozone 
Nonattainment Areas.'' John S. Seitz, Director, Office of Air Quality 
Planning and Standards, dated November 30, 1999. In this memoranda, we 
state that in order to determine whether a state has adopted all RACM 
necessary for attainment as expeditiously as practicable, the state 
will need to provide a justification as to why measures within the 
arena of potentially reasonable measures have not been adopted. The 
justification would need to support that a measure was not reasonably 
available for that area and could be based on technological or economic 
grounds, or a showing that it would not advance the attainment date.
    EPA has reviewed the RACM analysis provided in LDEQ's SIP submittal 
for the Baton Rouge nonattainment area and believes that the State has 
included sufficient documentation concerning the rejection of certain 
available measures as RACM for the specific Baton Rouge area.
    LDEQ conducted a mobile source analysis that consisted of a broad 
range of TCMs. As part of this analysis, LDEQ relied on an in-depth TCM 
evaluation study performed for the Baton Rouge area. LDEQ concluded 
that, relative to the total NOX reductions required for 
attainment of the 1-hour ozone NAAQS, additional TCMs that could 
potentially be implemented in the Baton Rouge area were only a small 
percentage (approximately 1%) of the emissions reductions needed for 
attainment and did not advance the attainment date. For more 
information regarding LDEQ's mobile source RACM analysis, including a 
description of the basic methodology employed to analyze TCM RACM, and 
a copy of the TCM evaluation study, please refer to the RACM TSD for 
this proposed action.
    An additional mobile source measure, the Vehicle Inspection and 
Maintenance (I/M) program has been implemented in the area. On-Board 
Diagnostics testing will be implemented in 2002. There is a state 
statute prohibiting the expansion of the I/M program beyond the five-
parish area [La. R.S. 30:2054.B(8)(a)]. The 2002 Louisiana legislative 
session is a ``fiscal only'' session. The next legislative session 
where expansion of the I/M program area could be considered would be 
the Regular Legislative Session of 2003. LDEQ concludes that the State 
has applied RACM for the I/M program because legislative authority is 
needed for any 
I/M program expansion, and that opportunity is not available until 
2003, and because the fleet in the Baton Rouge area is small 
(approximately 400,000 subject to the I/M program), LDEQ concludes that 
the state has applied RACM for the I/M program, in that expansion of 
the I/M program could not be accomplished so as to advance the 
attainment date for the Baton Rouge nonattainment area. LDEQ also 
considered off-road mobile RACM. In view of local feasibility and the 
economic impact of use restrictions, LDEQ has determined that further 
off-road measures are not RACM.
    LDEQ conducted a stationary source RACM analysis. A VOC major 
source analysis concluded that a 30% ``across the board'' reduction in 
VOCs yielded less than 1 ppb decrease in the ozone peak in all three 
episodes modeled in the attainment demonstration. Furthermore, 
Louisiana has implemented RACT on all major stationary sources of VOC 
in the Baton Rouge area. LDEQ concluded that further VOC reductions at 
this time are deemed as not cost effective and would not advance the 
attainment date for the Baton Rouge area.
    LDEQ conducted a NOX major source RACM analysis. Chapter 
4, Section 4.3 of the SIP submittal contains the proposed Baton Rouge 
NOX control strategy. In the Baton Rouge area the plan will 
reduce NOX by approximately 77 tons per day. LDEQ has 
adopted rule revisions, which are the subject of a separate EPA 
rulemaking (67 FR 48095, July 23, 2002), to control emissions from 
point sources of NOX in the Baton Rouge area. (LAC 33:III, 
Chapter 22, ``Control of Emissions of Nitrogen Oxides''). RACT is 
defined by EPA as the lowest achievable emission rate considering 
technical and economic feasibility. Based on the revised rule, LDEQ 
will be controlling emissions beyond levels that EPA has previously 
approved as RACT for such sources. Therefore, LDEQ concluded that the

[[Page 50402]]

Baton Rouge area NOX control plan meets RACM for major 
NOX sources.
    Area sources were also evaluated by LDEQ. The evaluation identified 
17 tons per day of ``potentially controllable'' VOC emissions 
reductions but this estimate was considered to be an overestimation in 
the Baton Rouge area because it did not take into account specific 
federal and state rules and regulations that are in effect to control 
such emissions. Based on its analysis that these categories are already 
controlled in the Baton Rouge area, LDEQ concluded that the amount of 
reduction available from additional controls on area sources were 
minimal, that there are little or no remaining potentially available 
emissions reductions, and that additional controls would not advance 
the attainment date for the Baton Rouge area.
    LDEQ also noted that NOX area sources were smaller and 
more numerous than the VOC area sources. Therefore, LDEQ concluded that 
control of NOX area sources would be expensive and would 
require an intensive effort. As a result, controls on these categories 
of sources was not considered reasonably available.
    Based on these analyses, LDEQ concluded that the additional set of 
evaluated measures are not reasonably available for the Baton Rouge 
area, because: (a) Some would require an intensive and costly effort 
for numerous small area sources, (b) the measures would not produce 
emission reductions sufficient to advance the attainment date in the 
Baton Rouge area and, therefore, should not be considered RACM for the 
Baton Rouge area. Please refer to the RACM TSD and LDEQ's RACM analysis 
for further information.
6. Revisions to the 15% ROPP, for the Control of VOC Emissions, the 
1990 Base Year Emissions Inventory, and the Post-1996 ROPP
    Under the 1990 Clean Air Act Amendments (CAAA), States have the 
responsibility to inventory emissions contributing to NAAQS 
nonattainment, to track these emissions over time, and to ensure that 
control strategies are being implemented that reduce emissions and move 
areas towards attainment. The CAAA require ozone nonattainment areas 
designated as moderate, serious, severe, and extreme to submit a plan 
within three years of 1990 to reduce VOC emissions by 15 percent within 
six years after 1990. The baseline level of emissions, from which the 
15 percent reduction is calculated, is determined by adjusting the base 
year inventory to exclude biogenic emissions and to exclude certain 
emission reductions not creditable towards the 15 percent. The 1990 
base year emissions inventory is the primary inventory from which the 
periodic inventory, the Reasonable Further Progress projection 
inventory, and the modeling inventory are derived.\2\ The base year 
inventory plays an important role in modeling demonstrations for areas 
classified as moderate and above.
---------------------------------------------------------------------------

    \2\ Further information on these inventories and their purpose 
can be found in the ``Emission Inventory Requirements for Ozone 
State Implementation Plans,'' U.S. Environmental Protection Agency, 
Office of Air Quality Planning and Standards, Research Triangle 
Park, North Carolina, March 1991.
---------------------------------------------------------------------------

    The air quality planning requirements for marginal to extreme ozone 
nonattainment areas are set out in section 182(a)-(e) of Title I of the 
CAAA. EPA has issued a General Preamble describing EPA's preliminary 
views on how EPA intends to review SIP revisions submitted under Title 
I, including requirements for the preparation of the 1990 base year 
inventory (see 57 FR 13502; April 16, 1992, and 57 FR 18070; April 28, 
1992). Because EPA is describing its interpretations here only in broad 
terms, the reader should refer to the General Preamble (57 FR 18070, 
Appendix B, April 28, 1992) for a more detailed discussion of the 
interpretations of Title I advanced in today's action and the 
supporting rationale.
    States containing ozone nonattainment areas classified as marginal 
to extreme are required under section 182(a)(1) of the 1990 CAAA to 
submit a final, comprehensive, accurate, and current inventory of 
actual ozone season, weekday emissions from all sources by November 15, 
1992. This inventory is for calendar year 1990 and is denoted as the 
base year inventory. It includes both anthropogenic and biogenic 
sources of VOC, NOX, and carbon monoxide (CO).
    The inventory is to address actual VOC, NOX, and CO 
emissions for the area during a peak ozone season, which is generally 
comprised of the summer months. All stationary point and area sources, 
as well as highway mobile sources within the nonattainment area, are to 
be included in the compilation. Available guidance for preparing 
emission inventories is provided in the General Preamble (57 FR 13498, 
April 16, 1992). EPA approved the Louisiana 1990 Base Year Emissions 
Inventories on March 15, 1995 (60 FR 13911).
    Section 182(c)(2)(B) of the Act requires each State having one or 
more ozone nonattainment areas classified as serious or worse to 
develop a plan by November 15, 1994, that provides for additional 
actual VOC reductions of at least three percent per year, averaged over 
each consecutive three year period, beginning six years after enactment 
of the Act, until such time as these areas have attained the NAAQS for 
ozone. These plans are referred to hereafter as Post-1996 ROPP. EPA 
approved the revisions to the Post-1996 ROPP for the Baton Rouge area 
on July 2, 1999 (64 FR 35930).
    The current revisions to the 1990 Base Year Emissions Inventory, 
the 15% Rate-of-Progress Plan, and the 9% Rate-of-Progress Plan were 
submitted as part of the December 31, 2001, Attainment Plan/Transport 
SIP. Specifically, they were submitted as part of the substitute 
contingency measures. The substitute contingency measures are the 
subject of a separate EPA rulemaking action (see 67 FR 35468, May 20, 
2002).
    The current revisions consist of emission reductions resulting from 
the installation of VOC emission controls at the Trunkline Gas 
Company--Patterson Compressor Station (hereinafter referred to as 
Trunkline or Trunkline facility) in St. Mary Parish. The Trunkline 
facility is located approximately 40 kilometers from the Baton Rouge 
ozone nonattainment area. In 1997, EPA issued a policy allowing 1-hour 
ozone nonattainment areas to take credit in their Post-1996 ROPP \3\ 
for emission reductions obtained from sources outside the designated 
nonattainment area, provided the sources are no farther away than 100 
km (for VOC sources) or 200 km (for NOX sources) away from 
the nonattainment area.\4\
---------------------------------------------------------------------------

    \3\ EPA has historically allowed a surplus emission reduction in 
ROPP to be credited towards meeting the section 172 and section 182 
requirements. EPA's rationale is that not allowing excess emission 
reductions to be used as contingency measures discourages areas from 
reducing emissions ``as expeditiously as practicable'' and is, 
therefore, inconsistent with section 172 of the CAA.
    \4\ EPA memorandum, ``Guidance for Implementing the 1-Hour Ozone 
and Pre-Existing PM10 NAAQS,'' from Richard D. Wilson, 
Acting Assistant Administrator for Air and Radiation, December 23, 
1997.
---------------------------------------------------------------------------

    The Trunkline Gas Company had not accounted for 13.4 tons per day 
of VOC emissions. As a result, the VOC emissions from this facility had 
not been included in the point source emissions inventory for 1990. 
Emissions reported in a corrected 1992 annual emissions inventory 
submitted to LDEQ June 6, 1997, are the best estimate of the source's 
1990 base year emissions. These emissions were added back to the 1990 
base year emissions inventory. The revised 1990 VOC base year inventory 
that included these Trunkline emissions would result in a 204.6 tons 
per day revised 1990 base year inventory.

[[Page 50403]]

    An additional 2.0 tons per day of emission reductions required were 
identified in the 15% ROPP revisions. The additional 2.0 tons per day 
were offset by 1.4 tons per day ``surplus'' 9% ROPP reduction from the 
Trunkline permit plus 0.6 tons per day of point source reductions (163 
tons per year or 0.45 tons per day of VOCs from the Dow Chemical permit 
and 56 tons per year or 0.15 tons per day of VOCs from the BASF 
Corporation permit).
    There was also an additional 1.2 tons per day of reductions 
required for the 9% ROPP identified in the revisions. These were taken 
from the 13.0 tons per day Trunkline emissions reductions that were 
netted from the post-90 emissions growth.
    See Table 1 below for a listing of the revisions to the emissions 
inventory. Table 2 below contains the revisions to the ROPPs. Table 3 
below itemizes the Trunkline emissions reductions. For further detail 
on the calculation of these emissions inventories please see the 
related prior rulemaking actions referenced above.

                   Table 1.--1990 Emissions Inventory
                             [Tons per day]
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Trunkline 1990 Base Year Emissions Inventory.................       13.4
1990 Adjusted VOC Base Year Inventory........................   \1\191.2
                                                              ----------
Revised 1990 Adjusted VOC Base Year Inventory................  \2\ 204.6
 
------------------------------------------------------------------------
\1\ From the approved 9% ROPP.
\2\ Includes Trunkline permit emissions.


                      Table 2.--Revisions to ROPPs
                             [Tons per day]
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Revised 3% Contingency Requirement...........................     \1\6.1
Additional 9% ROPP Reductions Required.......................    \2\ 1.2
Additional 15% ROPP Reductions Required......................   \3\ 2.0
------------------------------------------------------------------------
\1\ Three percent requirement times the total emissions inventory or
  0.03  x  204.6 tons per day.
\2\ Nine percent requirement times the Trunkline 1990 base year
  emissions inventory or 0.09  x  13.4 tons per day.
\3\ Fifteen percent requirement times the Trunkline 1990 base year
  emissions inventory or 0.15  x  13.4 tons per day.
a--Sources of additional 15% ROPP reductions is from approved 9% ROPP
  ``surplus'' (1.4 tons per day), plus point source reductions of 163
  tons per year or 0.45 tons per day of VOCs from Dow Chemical permit
  and 56 tons per year or 0.15 tons per day of VOCs from the BASF
  Corporation permit, totaling 2.0 tons per day.


                Table 3.--Trunkline Emissions Reductions
                             [Tons per day]
------------------------------------------------------------------------
 
------------------------------------------------------------------------
Trunkline Emissions Reductions...............................    \1\13.0
3% Contingency Requirement...................................    \2\ 6.1
Additional 9% ROPP Requirement...............................    \3\ 1.2
``Surplus'' 9% ROPP Reductions from Trunkline................       5.7
------------------------------------------------------------------------
\1\ Trunkline 1990 base year emissions inventory of 13.4 tons per day
  minus 0.4 tons per day of new allowables.

B. Environmental Protection Agency Review of the Submittals

1. Adequacy of the State's Demonstration of Attainment
Did the State Adequately Document the Techniques and Data Used To 
Derive the Modeling Input Data and Modeling Results?
    The submittals from the State adequately documented the techniques 
and data used to derive the modeling input data. The submittals 
adequately summarized the modeling outputs and the conclusions drawn 
from these model outputs. The submittals adequately documented the 
State's weight-of-evidence determinations and the bases for concluding 
that these determinations adequately support the attainment 
demonstration.
Did the Modeling Procedures and Input Data Used Comply With the 
Environmental Protection Agency Guidelines and Clean Air Act 
Requirements?
    Yes. The modeling procedures, and input data (including evaluation 
of the emissions inventory input and procedures), validation of the 
modeling results, and selection of episode days, meet the CAA 
requirements and are consistent with EPA's guidance.
Does the Weight-of-Evidence Determination Support the Attainment 
Demonstration?
    Yes, the weight-of-evidence determination, when viewed in aggregate 
with the modeling, shows attainment of the standard and thus EPA is 
proposing approval of the attainment demonstration.
2. Adequacy of the Emission Control Strategies
Do the Emission Control Strategies Meet the Requirements of the Clean 
Air Act?
    The selected emission control strategy, based upon modeling and the 
weight-of-evidence techniques, plus additional information regarding 
the effect of southeast Texas upon Baton Rouge, demonstrates attainment 
of the 1-hour ozone standard.
3. Adequacy of the Request for Extension of the Attainment Date
    The policy for the extension of an ozone attainment date is 
discussed above. How the State addressed it is discussed here.
a. Identification of the Area as a Downwind Area Affected by Ozone 
Transport
    The State submitted its Transport Demonstration on May 10, 2000, 
and provided supplemental information in the December 31, 2001, 
package. The State provided transport demonstration modeling and 
meteorological analyses. LDEQ applied the procedures used in the Ozone 
Transport Assessment Group (OTAG) modeling for evaluating ``significant 
contribution'' for the NOX SIP Call. This procedure has been 
used for other areas' transport demonstrations under the attainmentment 
date extension policy. The OTAG procedures appeared to equate a 
``significant contribution'' with a ``Zero-out'' modeling analysis of 
the upwind area's emissions resulting in a 2 ppb or greater impact to 
the downwind area. LDEQ used Urban Airshed Model V (UAM-V) to model an 
episode representing the most frequently occurring exceedance 
meteorological regime (i.e., the August 17-19, 1993 ozone episode) to 
quantify the contribution from southeast Texas (Houston/Galveston and 
Beaumont/Port Arthur areas). LDEQ ``Zero-out'' modeling analysis 
indicated a ``significant contribution,'' since the modeling results 
showed a contribution of approximately 2 to 6 ppb from the Houston/
Galveston nonattainment area to the five-parish Baton Rouge 
nonattainment area.
    The OTAG procedures for evaluating ``significant contribution'' 
also include a demonstration that the impact is large and/or frequent. 
To address the issues of the frequency of transport, LDEQ presented the 
analysis of meteorological and air quality data. LDEQ used the 
Classification and Regression Tree (CART) analysis technique to 
classify and analyze meteorological and air quality data for a five-
year period (1996-2000). The results indicated that 7 percent of the 
Baton Rouge exceedance days (i.e., 2 out of 28 exceedance days) were 
potentially associated with transport of ozone and/or precursor 
pollutants from the Houston area. For more information about the 
transport demonstration modeling, please refer to the Modeling TSD 
prepared for this document.
    In the information submitted in 2000, the modeling showed that 
emissions from the Houston/Galveston area of

[[Page 50404]]

southeast Texas resulted in impacts in a 1993 modeling episode. In the 
December 31, 2001 package, the air flow into Baton Rouge was not 
particularly conducive to showing transport from southeast Texas for 
the episodes modeled, but LDEQ submitted a model run that still showed 
a ``significant contribution'' of emissions from southeast Texas 
(Houston/Galveston and Beaumont/Port Arthur areas). We have reviewed 
LDEQ's submittals and are proposing to agree that LDEQ has demonstrated 
that on some occasions, emissions from the Houston/Galveston and 
Beaumont/Port Arthur areas have significant impacts on exceedances in 
the Baton Rouge area. This transported pollution happens frequently 
enough to adversely affect the area's ability to attain by its current 
attainment date, since the area is only allowed 3 exceedances in a 
three-year period. Thus for Baton Rouge to attain, controls in both the 
Houston/Galveston area and the Beaumont/Port Arthur area are necessary.
    In conclusion, EPA is proposing that Louisiana has demonstrated 
that during some Baton Rouge area exceedances, ozone levels are 
influenced by emissions from the Houston/Galveston and Beaumont/Port 
Arthur areas, and that the Houston/Galveston area and Beaumont/Port 
Arthur area emissions affect the Baton Rouge area's ability to meet 
attainment of the 1-hour ozone standard by November 15, 1999. 
Therefore, EPA proposes to find that the State's demonstration of ozone 
transport is consistent with the criteria in EPA's attainment date 
extension policy and meets the technical requirements established by 
the NOX SIP Call for a ``significant contribution''. Please 
refer to the TSD for more details.
b. Submittal of an Approvable Attainment Demonstration
    Based on our review of the attainment demonstration submitted by 
the State in December 31, 2001, EPA believes Louisiana has submitted an 
approvable attainment demonstration. As a part of this action, EPA is 
proposing to approve Louisiana's ground-level one-hour ozone attainment 
demonstration SIP for the Baton Rouge area. In addition, the State has 
adopted all of the emission control measures relied upon in the 
attainment demonstration but for one rule. On April 8, 2002, the 
Governor of Louisiana submitted rule revisions to LAC:33:III, Chapter 
22, ``Control of Emissions of Nitrogen Oxides,'' (AQ224), as a revision 
to the Louisiana SIP for lean burn engines in the BR ozone 
nonattainment area and requested that EPA act on the rule revision 
concerning NOX RACT for lean burn engines through ``parallel 
processing.'' See 40 CFR Part 51, Appendix V for more information on 
``parallel processing'' process. EPA has agreed to parallel process 
this rule revision and will complete its rulemaking on this revision 
before taking final action on the attainment demonstration or an 
attainment date extension. EPA is proposing to extend the attainment 
date for the Baton Rouge area, only if EPA takes final action to 
approve the attainment demonstration and any other required local 
measures.
    LDEQ has requested that the EPA grant an extension of the 
attainment date for the 1-hour ozone NAAQS for the Baton Rouge area to 
November 15, 2005. In keeping with EPA's attainment date extension 
policy, the November 15, 2005 date is well before the Houston/Galveston 
attainment date of November 15, 2007. The Baton Rouge attainment 
demonstration relies heavily on NOX controls to be 
implemented as expeditiously as possible, but no later than May 1, 
2005. It is expected that the Houston/Galveston area and the Beaumont/
Port Arthur area will have achieved sufficient emissions reductions to 
lower the background concentration of ozone and ozone precursors in the 
Baton Rouge area. LDEQ feels that with a combination of local and 
federal controls, and with the expected emissions reductions from the 
upwind area, the Baton Rouge nonattainment area can attain by November 
15, 2005. Thus, EPA believes that the November 15, 2005, attainment 
date is as ``expeditiously as practicable'' for the Baton Rouge area.
c. Adoption of All Applicable Local Measures Required Under the Area's 
Current Ozone Classification
    As noted above, Louisiana has completed the adoption of all local 
measures required by the Act for the area's current classification with 
the exception of NOX RACT, and has submitted these revisions 
to EPA for approval. EPA is proposing to extend the attainment date for 
the Baton Rouge area, only if EPA takes final action to approve all 
applicable required local measures.
d. Implementation of All Adopted Measures as Expeditiously as 
Practicable and No Later Than the Time Upwind Controls Are Expected
    In anticipation of the implementation of certain upwind controls in 
the Houston/Galveston and Beaumont/Port Arthur areas, Louisiana has 
adopted State regional NOX controls requiring implementation 
as expeditiously as practicable, but no later than May 1, 2005. As a 
part of the Attainment Demonstration/Transport SIP submitted by 
Louisiana, the State has committed to implementing all adopted measures 
as expeditiously as practicable and no later than the time upwind 
controls are expected. For more information please refer to the 
Modeling TSD and to the State's Control Strategy (Chapter 4 of the 
SIP). Therefore, EPA proposes that the State's sumbittals are 
consistent with this criterion of the extension policy.
    EPA concludes that, at the present time, the State has addressed 
the conditions for an attainment date extension. EPA believes that 
Louisiana has met the criteria for obtaining an attainment date 
extension under the conditions contained in EPA's July 16, 1998, 
attainment date extension policy, provided that EPA approves the 
attainment demonstration and any local measures which require EPA 
approval to qualify for the extension. Therefore, EPA proposes to 
extend the attainment date for the Baton Rouge area to November 15, 
2005.
    To the extent that comments received on EPA's March 25, 1999 
document, ``Extension of Attainment Dates for Downwind Transport 
Areas,'' 64 FR 14441, are applicable to this rulemaking, EPA will 
address and respond to these comments in its final rulemaking action.
4. Determination of RACM Availability
    EPA has reviewed LDEQ's SIP submittal and LDEQ's analysis to 
evaluate emission levels of NOX and VOC and their 
relationships to the application of current and anticipated control 
measures expected to be implemented in the five-parish Baton Rouge 
serious nonattainment area.
    Based on this review, EPA proposes to conclude that the additional 
set of evaluated measures are not reasonably available for the Baton 
Rouge area, because: (a) The additional set of measures would require 
an intensive and costly effort for numerous small area sources, and (b) 
the measures would not produce emission reductions sufficient to 
advance the attainment date in the Baton Rouge area and, therefore, 
should not be considered RACM for the specific area.
    EPA reached this conclusion primarily because the reductions 
expected to be achieved by the potential RACM measures are very small. 
These potential reductions are far less than the emissions reductions 
needed to advance the date for attainment in the Baton Rouge area. LDEQ 
has concluded from its modeling analysis, and we agree, that 
NOX emission reductions in Baton

[[Page 50405]]

Rouge are the most effective way to reduce ozone in the Baton Rouge 
area. VOC reductions are not as effective as NOX in reducing 
ozone, and further local VOC reductions in this area would not produce 
significant ozone reductions in the Baton Rouge area. EPA agrees with 
LDEQ that VOC reductions would not advance the attainment date and are 
not as effective in reducing ozone in the Baton Rouge area, as 
demonstrated in the modeling.
    Furthermore, as shown in the modeled attainment demonstration, the 
Baton Rouge area also relies upon emissions reductions from outside of 
the nonattainment area and from federal rules with implementation dates 
prior to 2005. There are no other reasonably available control measures 
that could advance the attainment date for the Baton Rouge area prior 
to full implementation, by 2005, of all measures in Louisiana's SIP 
control strategy for the Baton Rouge area.
    Although EPA encourages areas to implement available RACM measures 
as potentially cost-effective methods to achieve emissions reductions 
in the short term, EPA does not believe that section 172(c)(1) requires 
implementation of potential RACM measures that either require costly 
implementation efforts or produce relatively small emissions reductions 
that will not be sufficient to allow the Baton Rouge area to achieve 
attainment in advance of full implementation of all other required 
measures. Therefore, EPA proposes to conclude that the additional set 
of evaluated measures are not reasonably available for the Baton Rouge 
area and should not be considered RACM for the specific area.
5. Adequacy of ROPPs and the 1990 Base Year Inventory
    We are proposing approval of the revised 1990 Base Year Emissions 
Inventory, the 15% Rate-of-Progress Plan, and the 9% Rate-of-Progress 
Plan submitted as part of the December 31, 2001, Attainment Plan/
Transport SIP.
    These plans demonstrate that ozone forming emissions are reduced 
from the baseline emissions by 15% during the time period of 1990-1996 
and by 9% during the time period of 1996-1999. We are also proposing to 
approve the MVEBs associated with the revisions to these plans. 
Additionally, we are proposing to approve the changes to the 1990 base 
year emissions inventory for the Baton Rouge area.
6. Completeness Finding
    The Baton Rouge area Attainment Plan and Transport SIP is deemed to 
be complete by operation of law. Section 110(k)(1)(B) of the CAA states 
that a plan or plan revision that has not been determined by the 
Administrator to have failed to meet the minimum criteria by the date 6 
months after receipt of the submission shall on that date be deemed by 
operation of law to meet such minimum criteria. The Baton Rouge area 
SIP was deemed complete by operation of law as of June 30, 2002.

III. Proposed Action

    EPA proposes to approve the following actions on the submittal of 
the Attainment Plan/Transport SIP (December 31, 2001) and related 
submittals (May 10, 2000, February 27, 2002, February 1, 2002, April 8, 
2002, and May 20, 2002):
    1. EPA is proposing to approve the ground-level one-hour ozone 
attainment demonstration SIP for the Baton Rouge area, which shows 
attainment by November 15, 2005, provided that EPA issues a final 
approval of all other required local measures.
    2. EPA is proposing to approve the Transport Demonstration and the 
State's request to extend the ozone attainment date for the Baton Rouge 
area to November 15, 2005, while retaining the area's current 
classification as a serious ozone nonattainment area, provided that EPA 
issues a final approval of the State's attainment demonstration and any 
other required local measures.
    3. EPA is proposing to approve the Attainment Demonstration SIP's 
associated MVEBs, only until the MVEBs are revised according to the 
State's enforceable commitment.
    4. EPA is proposing to approve the RACM Analysis for the Baton 
Rouge area.
    5. EPA is proposing to approve the State's TCM.
    6. EPA is proposing to approve the revisions to the 15% ROPP for 
the control of VOC emissions, the 1990 base year emissions inventory, 
and the Post-1996 ROPP emissions.
    7. EPA is proposing to withdraw our June 24, 2002, rulemaking 
action entitled ``Determination of Nonattainment as of November 15, 
1999, and Reclassification of the Baton Rouge Ozone Nonattainment 
Area.''
    8. EPA is proposing to approve the State's enforceable commitments 
regarding MOBILE6.
    9. EPA is proposing to approve the State's enforceable commitment 
to conduct and submit a mid-course review by May 1, 2004. If the 
subsequent analyses conducted by the State as part of the mid-course 
review indicates additional reductions are needed for the Baton Rouge 
area to attain the ozone standard, EPA will require the State to 
implement additional controls as soon as possible until attainment is 
demonstrated through an approvable attainment demonstration.

IV. Administrative Requirements

A. Executive Order 12866

    The Office of Management and Budget (OMB) has exempted this 
regulatory action from Executive Order 12866, entitled ``Regulatory 
Planning and Review.''

B. 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 and reasonably feasible 
alternatives considered by the Agency.
    This rule is not subject to Executive Order 13045 because it does 
not involve decisions intended to mitigate environmental health or 
safety risks.

C. Executive Order 13084

    Under Executive Order 13084, EPA may not issue a regulation that is 
not required by statute, that significantly affects or uniquely affects 
the communities of Indian tribal governments, and that imposes 
substantial direct compliance costs on those communities, unless the 
Federal government provides the funds necessary to pay the direct 
compliance costs incurred by the tribal governments, or EPA consults 
with those governments. If EPA complies by consulting, Executive Order 
13084 requires EPA to provide to the Office of Management and Budget, 
in a separately identified section of the preamble to the rule, a 
description of the extent of EPA's prior consultation with 
representatives of affected tribal governments, a summary of the nature 
of their concerns, and a statement supporting the need to issue the 
regulation. In addition, Executive Order 13084 requires EPA to develop 
an effective process permitting elected officials and other 
representatives of Indian tribal governments ``to provide meaningful 
and timely input in the development of

[[Page 50406]]

regulatory policies on matters that significantly or uniquely affect 
their communities.'' Today's proposed rule does not significantly or 
uniquely affect the communities of Indian tribal governments. This 
action does not involve or impose any requirements that affect Indian 
Tribes. Accordingly, the requirements of section 3(b) of Executive 
Order 13084 do not apply to this rule.

D. 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 proposed 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.
    This rule 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, because it 
merely approves a state rule implementing a federal standard, and does 
not alter the relationship or the distribution of power and 
responsibilities established in the Clean Air Act. Thus, the 
requirements of section 6 of the Executive Order do not apply to this 
rule.

E. Regulatory Flexibility

    The Regulatory Flexibility Act (RFA) generally requires an agency 
to conduct a regulatory flexibility analysis of any rule subject to 
notice and comment rulemaking requirements unless the agency certifies 
that the rule will not have a significant economic impact on a 
substantial number of small entities. Small entities include small 
businesses, small not-for-profit enterprises, and small governmental 
jurisdictions.
    This rule will not have a significant impact on a substantial 
number of small entities because SIP approvals under section 110 and 
subchapter I, part D of the Clean Air Act do not create any new 
requirements but simply approve requirements that the State is already 
imposing. Therefore, because the Federal SIP approval does not create 
any new requirements, I certify that this action will not have a 
significant economic impact on a substantial number of small entities.
    Moreover, due to the nature of the Federal-State relationship under 
the Clean Air Act, preparation of flexibility analysis would constitute 
Federal inquiry into the economic reasonableness of state action. The 
Clean Air Act forbids EPA to base its actions concerning SIPs on such 
grounds. Union Electric Co., v. U.S. EPA, 427 U.S. 246, 255-66 (1976); 
42 U.S.C. 7410(a)(2).

F. Unfunded Mandates

    Under sections 202 of the Unfunded Mandates Reform Act of 1995 
(''Unfunded Mandates Act''), signed into law on March 22, 1995, EPA 
must prepare a budgetary impact statement to accompany any proposed or 
final rule that includes a Federal mandate that may result in estimated 
costs to State, local, or tribal governments in the aggregate; or to 
the private sector, of $100 million or more. Under section 205, EPA 
must select the most cost-effective and least burdensome alternative 
that achieves the objectives of the rule and is consistent with 
statutory requirements. Section 203 requires EPA to establish a plan 
for informing and advising any small governments that may be 
significantly or uniquely impacted by the rule.
    EPA has determined that the approval action proposed does not 
include a Federal mandate that may result in estimated costs of $100 
million or more to either State, local, or tribal governments in the 
aggregate, or to the private sector. This Federal action proposes to 
approve pre-existing requirements under State or local law, and imposes 
no new requirements. Accordingly, no additional costs to State, local, 
or tribal governments, or to the private sector, result from this 
action.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Hydrocarbons, 
Nitrogen oxides, Ozone, Reporting and recordkeeping requirements.

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

    Dated: July 25, 2002.
Gregg A. Cooke,
Regional Administrator, Region 6.

List of Subjects in 40 CFR Part 52

    Environmental protection, Air pollution control, Hydrocarbons, 
Nitrogen oxides, Ozone, Reporting and recordkeeping requirements.

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

    Dated: July 25, 2002.
Gregg A. Cooke,
Regional Administrator, Region 6.
[FR Doc. 02-19441 Filed 8-1-02; 8:45 am]
BILLING CODE 6560-50-P