20404 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

public hearing that appeared in the

Federal Register on January 24, 2000,

(65 FR 3629), announced that a public

hearing was scheduled for April 20,

2000 at 10 a.m., in room 2615, Internal

Revenue Building, 1111 Constitution

Avenue NW., Washington, DC. The

subject of the public hearing is proposed

regulations under section 367(b), of the

Internal Revenue Code. The deadline for

requests to speak and outlines of oral

comments expired on March 31, 2000.

The notice of proposed rulemaking

and notice of public hearing, instructed

those interested in testifying at the

public hearing to submit a request to

speak and an outline of the topics to be

addressed. As of April 11, 2000, no one

has requested to speak. Therefore, the

public hearing scheduled for April 20,

2000, is cancelled.

Cynthia E. Grigsby,

Chief, Regulations Unit, Assistant Chief

Counsel (Corporate).

[FR Doc. 00–9409 Filed 4–14–00; 8:45 am]

BILLING CODE 4830–01–P

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 52

[IL196–1; MO–097–1097; FRL–6578–2]

Approval and Promulgation of

Implementation Plans; Illinois and

Missouri; Ozone

AGENCY: Environmental Protection

Agency.

ACTION: Proposed rule.

SUMMARY: The Environmental Protection

Agency (EPA) is proposing to approve

the Illinois and Missouri 1-hour ozone

attainment demonstration State

Implementation Plans (SIPs) for the St.

Louis moderate ozone nonattainment

area. The attainment demonstration SIPs

are addressed in Illinois Environmental

Protection Agency (IEPA) submittals

dated November 15, 1999 and February

10, 2000 and in Missouri Department of

Natural Resources (MDNR) submittals

dated November 10, 1999 and January

19, 2000. In the alternative, the EPA is

proposing to disapprove the attainment

demonstration if: Illinois and Missouri

do not revise the attainment

demonstration modeling and analyses to

incorporate corrections to the 1996 base

year emissions inventory and

successfully demonstrate attainment of

the 1-hour standard based on the

revised modeling; Illinois or Missouri

do not submit proposed regional Oxides

of Nitrogen (NOX) emission control

regulations for Electric Generating Units

(EGUs) by June 2000 and final adopted

regional (NOX) emission control

regulations for EGUs by December 2000;

or Missouri does not submit a proposed

motor vehicle emissions budget by June

30, 2000. The EPA is proposing to:

approve an exemption from (NOX)

emission control requirements for

Reasonably Available Control

Technology (RACT) for the Illinois

portion of the St. Louis ozone

nonattainment area; extend the ozone

attainment date for the entire St. Louis

ozone nonattainment area to November

15, 2003 while retaining the area’s

current classification as a moderate

ozone nonattainment area; and approve

the transportation conformity motor

vehicle emissions budget submitted by

Illinois for the Illinois portion of the St.

Louis ozone nonattainment area. The

final approvals of the extension of the

ozone attainment date and the motor

vehicle emissions budgets are

contingent on the final approval of the

ozone attainment demonstration. The

final approval of the attainment

demonstration is contingent on the final

approval of the regional (NOX) emission

control regulations and on the submittal

of adequate motor vehicle emissions

budgets. The final approval of the (NOX)

RACT exemption for Illinois is

contingent on the final approval of an

attainment demonstration that does not

rely on (NOX) emission reductions

resulting from (NOX) RACT

implementation in the Illinois portion of

the St. Louis nonattainment area. The

EPA is proposing to disapprove Illinois’

request for exemption from (NOX)

requirements for New Source Review

(NSR) and general conformity.

DATES: Written comments must be

received on or before June 16, 2000.

ADDRESSES: Written comments should

be sent to: Jay Bortzer, Chief, Regulation

Development Section, Air Programs

Branch (AR-18J), U.S. Environmental

Protection Agency, 77 West Jackson

Boulevard, Chicago, Illinois 60604; or

Wayne Leidwanger, Chief, Air Planning

and Development Branch, U.S.

Environmental Protection Agency, 901

North 5th Street, Kansas City, Kansas

66101.

Copies of the States’ submittals and

EPA’s Technical Support Document

(TSD) for this proposed rule, and other

relevant materials are available for

public inspection during normal

business hours at the following

addresses: United States Environmental

Protection Agency, Region 5, Air and

Radiation Division, 77 West Jackson

Boulevard, Chicago, Illinois 60604

(please telephone Mark Palermo at (312)

886–6082 before visiting the Region 5

office); United States Environmental

Protection Agency, Region 7, Air,

Radiation, and Toxics Division, 901

North 5th Street, Kansas City, Kansas

66101.

FOR FURTHER INFORMATION CONTACT:

Edward Doty, Regulation Development

Section, Air Programs Branch (AR–18J),

U.S. Environmental Protection Agency,

Region 5, 77 West Jackson Boulevard,

Chicago, Illinois 60604, Telephone

Number (312) 886-6057, E-Mail

Address: doty.edward@epamail.epa.gov;

or Aaron Worstell, Air Planning and

Development Branch, U.S.

Environmental Protection Agency,

Region 7, 901 North 5th Street, Kansas

City, Kansas 66101, Telephone Number

(913) 551–7787, E-Mail Address:

worstell.aaron@epa.gov.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Background

A. Basis for the States’ Attainment

Demonstration SIPs

B. Components of a Modeled Attainment

Demonstration

C. Framework for Proposing Action on the

Attainment Demonstration SIP

D. Criteria for Attainment Date Extensions

E. Criteria for (NOX) Control Exemptions

II. Technical Review of the Submittals

A. Summary of the State Submittals

1. General Information

2. Modeling Procedures and Input Data

3. Modeling Results

4. Emission Control Strategies

5. Transportation Conformity

6. Petition for NOx Control Exemption

B. Environmental Protection Agency

Review of the Submittals

1. Adequacy of the States’ Demonstrations

of Attainment

2. Adequacy of the Emissions Control

Strategies

3. Adequacy of the Request for Extension

of the Attainment Date

4. Adequacy of the NOx Control Exemption

Request

III. Proposed Action

IV. Administrative Requirements

A. Executive Order 12866

B. Executive Order 13045

C. Executive Order 13084

D. Executive Order 13132

E. Regulatory Flexibility

F. Unfunded Mandates

I. Background

A. Basis for the States’ Attainment

Demonstration SIPs

What are the Relevant Clean Air Act

Requirements?

The Clean Air Act (Act) requires the

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

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20405

1Memorandum, ‘‘Ozone Attainment

Demonstrations,’’ issued March 2, 1995. A copy of

the memorandum may be found on EPA’s web site

at: http://www.epa.gov/ttn/oarpg/t1pgm.html.

2Letter from Mary A. Gade, Director, State of

Illinois Environmental Protection Agency to

Environmental Council of States (ECOS) Members,

dated April 13, 1995.

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 8, 1979).

Ground-level ozone is not emitted

directly by sources. Rather, Volatile

Organic Compounds (VOC) and 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.

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 or in its immediate

downwind environs.

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 from the 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 the areas’ ozone

design values for 1987 through 1989.

The St. Louis ozone nonattainment area

was classified as moderate and its

attainment date was November 15, 1996.

The St. Louis ozone nonattainment area

is defined (40 CFR 81.314 and 81.326)

to contain Madison, Monroe, and St.

Clair Counties in Illinois, and Franklin,

Jefferson, St. Charles, and St. Louis

Counties and St. Louis City in Missouri.

The requirements of the Act for ozone

attainment demonstrations for moderate

ozone nonattainment areas are

determined by considering several

sections of the Act. Section 172(c)(6) of

the Act requires 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 to provide for attainment by

the applicable attainment date. Section

172(c)(1) requires the implementation of

all reasonably available control

measures (including Reasonably

Available Control Technology (RACT))

and requires the SIP to provide for

attainment of the NAAQS. Section

182(b)(1)(A) requires the SIP to provide

for specific annual reductions in

emissions of VOC and NOX as necessary

to attain the ozone NAAQS by the

applicable attainment date. Finally,

section 182(j)(1)(B) requires the use of

photochemical grid modeling or other

methods judged to be at least as

effective to demonstrate attainment of

the ozone NAAQS in multi-state ozone

nonattainment areas. As part of today’s

proposal, EPA is proposing action on

the attainment demonstration SIP

revisions submitted by Illinois and

Missouri for the St. Louis multi-state

ozone nonattainment area and its

associated ozone modeling domain.

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

necessary to achieve attainment. The

attainment demonstration SIPs must

include motor vehicle emission budgets

for transportation conformity purposes.

Transportation conformity is a process

for ensuring that States consider the

effects of emissions associated with

federally-funded transportation

activities on attainment of the standard.

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.

What Is the History and Time Frame for

the State Attainment Demonstration SIP

and How Is It Related to Regional NOX

Controls?

Notwithstanding significant efforts by

the States, in 1995 EPA recognized that

many States in the eastern half of the

United States could not meet the

November 1994 time frame for

submitting an attainment demonstration

SIP because emissions of NOX and VOC

in upwind States (and the ozone formed

by these emissions) affected these

nonattainment areas and the full impact

of this effect had not yet been

determined. This phenomenon is called

ozone transport.

On March 2, 1995, Mary D. Nichols,

EPA’s then Assistant Administrator for

Air and Radiation, issued a

memorandum to EPA’s Regional

Administrators acknowledging the

efforts made by the States but noting the

remaining difficulties in making

attainment demonstration SIP

submittals. 1 Recognizing the problems

created by ozone transport, the March 2,

1995 memorandum called for a

collaborative process among the States

in the eastern half of the Country to

evaluate and address transport of ozone

and its precursors. This memorandum

led to the formation of the Ozone

Transport Assessment Group (OTAG) 2

and provided for the States to submit

the attainment demonstration SIPs

based on the expected time frames for

OTAG to complete its evaluation of

ozone transport.

In June 1997, OTAG concluded and

provided EPA with recommendations

regarding ozone transport. The OTAG

generally concluded that transport of

ozone and the precursor NOX is

significant and should be reduced

regionally to enable States in the eastern

half of the Country to attain the ozone

NAAQS.

Building upon the OTAG

recommendations and technical

analyses, in November 1997, EPA

proposed action addressing the ozone

transport problem. In its proposal, the

EPA found that current SIPs in 22 States

and the District of Columbia (23

jurisdictions) were insufficient to

provide for attainment and maintenance

of the 1-hour standard because they did

not regulate NOX emissions that

significantly contribute to ozone

transport. 62 FR 60318 (November 7,

1997). The EPA finalized that rule in

September 1998, calling on the 23

jurisdictions, including Illinois and

Missouri, to revise their SIPs to require

NOX emission reductions within each

State to a level consistent with a NOX

emissions budget identified in the final

rule. 63 FR 57356 (October 27, 1998).

20406 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

3EPA is also requiring regional NOX emission

reductions under its authority in section 126 of the

Act to assure that reductions occur in upwind areas

which have been shown to impact attainment of the

ozone standard in downwind areas.

4On March 18, 1999, 64 FR 13384, the EPA

proposed to reclassify the St. Louis area to a serious

ozone nonattainment area based on continued

monitored violations of the 1-hour ozone standard.

The EPA also issued a notice of the St. Louis area’s

potential eligibility for an attainment date

extension.

This final rule is commonly referred to

as the NOX SIP call.3

Although Illinois and Missouri do not

rely on the full ozone impacts and

regional NOX emission reduction

requirements of the NOX SIP call in the

ozone attainment demonstration SIPs

reviewed here, they do rely, in part, on

regional, statewide NOX emission

reductions for their own States and for

States upwind of Illinois and Missouri.

In developing the attainment

demonstration, Illinois and Missouri

originally anticipated the

implementation of the NOX SIP call.

Because of a court-ordered stay of the

submission deadline for SIPs in

response to the NOX SIP call, Illinois

and Missouri reconsidered the role and

magnitude of regional NOX reductions.

As noted below, the NOX SIP call has

substantially been upheld by the U.S.

Court of Appeals for the District of

Columbia; accordingly, Illinois and

Missouri may expect even more upwind

NOX emission reductions than they

addressed in developing the attainment

demonstration.

What Is the Time Frame for Taking

Action on the Attainment

Demonstration SIPs?

The States submitted the attainment

demonstration SIP revisions and

supporting documentation between

November 1999 and February 2000. The

EPA believes that it is important to keep

the process moving forward in

evaluating these plans and, as

appropriate, approving them. Thus, in

today’s Federal Register, EPA is

proposing to approve the plans if the

States make the additional submittals

called for in this document. The EPA,

however, proposes to disapprove the

plans if the States do not submit all of

the emission control regulations

required to support the attainment of

the 1-hour ozone standard as

demonstrated in these SIPs, do not

correct the ozone attainment

demonstration modeling to incorporate

changes recently made in the ozone

precursor emissions inventory, or do not

have adequate motor vehicle emission

budgets to support transportation

conformity determinations. The States

are expected to submit the proposed

rules by June 2000, along with any

proposed revisions to the ozone

attainment demonstration modeling.

The States are expected to submit final

adopted measures, and final revisions to

the attainment demonstration, no later

than December 2000. The EPA intends

to act on the State NOX regulations in

separate rulemaking actions, and will

not take final action to approve the

attainment demonstration until it

completes action on the rules.

The anticipated schedule for actions

on the States’ submittals has been set

forth in a recent filing in the United

States District Court for the District of

Columbia. Sierra Club v. Carol Browner

(D.C.D.C. No. 98–02733). The EPA

intends to complete rulemaking on the

attainment demonstration and

attainment date extension for the St.

Louis area when it completes action on

the submittals from both Missouri and

Illinois of the additional control

measures necessary for the attainment

demonstration. The following outlines

the anticipated schedule for EPA action.

If, by June 30, 2000, either Illinois or

Missouri does not submit proposed

regulations for the emission control

measures (local and regional) needed to

achieve attainment of the 1-hour ozone

standard as indicated by the attainment

demonstration, and any proposed

revisions to the attainment

demonstration (to include any proposed

revisions to the motor vehicle emissions

budgets) determined to be necessary

after remodeling the 1996 base year

ozone levels to account for revised 1996

base year emissions, the EPA intends to

take final action on the proposed

reclassification of the St. Louis area 4 to

serious ozone nonattainment no later

than August 1, 2000. If either State does

not submit final adopted emission

control measures and any final revisions

to the attainment demonstration

(including any final revisions to the

motor vehicle emissions budgets) by

December 31, 2000, the EPA intends to

take final action on the reclassification

of the area to serious nonattainment for

ozone no later than February 1, 2001.

The EPA plans to send a notice of final

rulemaking on the attainment

demonstration and attainment date

extension to the Federal Register no

later than February 22, 2001.

Due to the circumstances in which the

SIP submissions arose, the EPA is

proposing two alternative courses of

action: approval or disapproval in the

alternative. The proposal for approval

provides that the States must take

additional actions to obtain final

approval. Failure by the States to

complete these additional actions will

result in EPA’s disapproval of the SIPs.

B. Components of a Modeled

Attainment Demonstration

The EPA provides (Guidance on the

Use of Modeled Results to Demonstrate

Attainment of the Ozone NAAQS, EPA–

454/B–95–007, June 1996) that States

may rely on a modeled attainment

demonstration supplemented with

additional evidence to demonstrate

attainment. To have a complete

modeling demonstration submission,

States should have submitted the

required modeling analyses and

identified any additional evidence that

EPA should consider in evaluating

whether the area will attain the

standard. Additional required

components are discussed below.

What EPA Guidelines Apply to the

Attainment Demonstration Submittals?

The following documents 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.

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20407

5The initial, ‘‘ramp-up’’ days for each episode are

excluded from this determination.

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. Paper, ‘‘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’’).

What Are the Modeling Requirements

for the Attainment Demonstration?

For purposes of demonstrating

attainment, the Act requires States

containing portions of a multi-state

moderate ozone nonattainment area to

use photochemical grid modeling or an

analytical method judged by EPA to be

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 permitted under

certain conditions by EPA’s guidance.

When the predicted concentrations are

above the standard or upper limit, EPA

guidance allows for an optional weightof-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.

The EPA guidance identifies the

features of a modeling analysis that are

essential to obtain credible results. First,

the State must develop and implement

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 must

select 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 needs to identify 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

needs to determine the grid resolution.

The horizontal and vertical resolutions

in the model affect the dispersion and

transport of emission plumes.

Artificially large grid cells (too few

vertical layers and horizontal grids) may

dilute concentrations and may not

properly consider impacts of complex

terrain, complex meteorology, and land/

water interfaces. Fifth, the State needs

to generate meteorological and

emissions data that describe

atmospheric conditions and emissions

inputs reflective of the selected high

ozone days. Finally, the State needs to

verify 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.

The 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.

The deterministic test requires the

State to compare predicted 1-hour daily

maximum ozone concentrations for each

modeled day 5 to the attainment level of

0.124 ppm. If none of the predictions

exceed 0.124 ppm, the test is passed.

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 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

20408 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

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.

The 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-ofevidence 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. The EPA’s guidance contains no

limit on how close a modeled

attainment test must be to passing to

conclude that other evidence besides an

attainment test is sufficiently

compelling to suggest 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

Besides the Modeled Attainment

Demonstration, What Other Issues Must

Be Addressed in the Attainment

Demonstration SIP?

In addition to the modeling analysis

and weight-of-evidence determination

demonstrating attainment, the 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 Modeled

Attainment Demonstration State

Implementation Plan

To receive final approval of the

attainment demonstration SIP, the State

must have adopted the emission control

measures required under the Act for the

area’s classification or must have

established negative source declarations

for the source categories for which the

area has no major sources that are

subject to Clean Air Act requirements

for such sources. All required emission

controls must be implemented prior to

the beginning of the ozone season (April

through October in the St. Louis area, 40

CFR part 58) in the area’s attainment

year to assure attainment of the ozone

standard in the attainment year.

The attainment demonstration must

incorporate the emission impacts of,

and the SIP submittal must address the

rule development for, any additional

emission control measures needed to

achieve attainment. The rules for these

emission controls must also have been

adopted before the EPA can finally

approve the attainment demonstration.

The emission controls for these sources

must be implemented prior to the

beginning of the ozone season in the

attainment year.

For purposes of fully approving the

State’s 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.

Table 1 presents a summary of the

Clean Air Act requirements that need to

be met for a moderate ozone

nonattainment area for the 1-hour ozone

standard. These requirements are

specified in sections 182(b) and 182(f) of

the Act. Information on additional

measures that Illinois and Missouri have

adopted and relied on in their SIP

submissions is not shown in this table,

but is addressed later in this proposed

rule.

Table 1—Clean Air Act Requirements For

Moderate Nonattainment Areas

• New Source Review (NSR) regulations

for VOC and NOX, including an offset ratio

of 1.15:1 and a major VOC and NOX source

size cutoff of 100 tons per year (TPY)

• Reasonably Available Control

Technology (RACT) for VOC and NOX

• 15 percent Rate-Of-Progress (ROP) plan

for VOC through 1996

• 1990 baseline emissions inventory for

VOC and NOX

• Periodic emissions inventory and source

emission statement regulations

• Vehicle inspection and maintenance (I/

M) program

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. For transportation

conformity purposes, the estimate of

motor vehicle emissions in a control

strategy SIP such as an attainment

demonstration (converted to a typical

ozone season week day level) is defined

as the motor vehicle emissions budget.

The motor vehicle emissions budget

must meet certain adequacy criteria

which are listed in the Transportation

Conformity Rule (40 CFR 93.118) before

the budget can be approved as part of

the attainment demonstration SIP.

When a motor vehicle emissions budget

is found to be adequate, it is used to

determine the conformity of the

transportation plans and programs to

the SIP, as required by section 176(c) of

the Act. The motor vehicle emissions

budget must meet adequacy criteria (40

CFR part 93) before the attainment

demonstration SIP 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?

The EPA’s policy regarding an

extension of the ozone attainment date

for the St. Louis area is fully addressed

in a EPA’s initial notice of proposed

rulemaking dated March 18, 1999. 64 FR

13384. The March 18, 1999 document

proposed to reclassify the St. Louis area

to a serious ozone nonattainment area,

but also provided notice of the area’s

potential eligibility for an attainment

date extension based on a July 16, 1998

EPA guidance memorandum. In today’s

document, EPA proposes to approve the

States’ request for an attainment date

extension under that policy. The

specifics of the attainment date policy

are repeated below for clarity.

On July 16, 1998, a guidance

memorandum entitled ‘‘Extension of

Attainment Dates for Downwind

Transport Areas’’ was issued by the

EPA. That memorandum included

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20409

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.

That memorandum stated that the 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 St.

Louis area is granted an attainment date

extension, it would no longer be subject

to a reclassification to serious

nonattainment for ozone and no longer

subject to the additional emission

control requirements that would result

from the reclassification to serious

nonattainment.

Illinois and Missouri have requested

an extension of the attainment date for

the St. Louis nonattainment area in

conjunction with the ozone attainment

demonstration submittals. The ozone

attainment demonstration considers

2003 as the revised ozone attainment

year. The 2003 attainment year reflects

the NOX emission control deadline

contained in the NOX SIP call and the

NOX emission control deadline that EPA

is considering to address section 126

petitions currently before it.

E. Criteria for NOX Control Exemptions

What Are the Clean Air Act

Requirements and EPA Policy With

Regard to NOX Emission Controls and

Exemptions From the NOX Emission

Control Requirements?

The State of Illinois has petitioned for

an exemption from excess NOX

emission reductions pursuant to section

182(f)(2) of the Act. The State is seeking

an exemption from requirements for

NOX Reasonably Available Control

Technology (NOX RACT), New Source

Review (NSR), and general conformity.

The following discusses the Act

requirements and EPA policy with

regard to NOX emission controls and

emission control exemptions,

particularly as such policy deals with

the Illinois petition.

Section 182(f)(1) of the Act requires

SIPs to include emission control

provisions for major stationary sources

of NOX as required for major stationary

sources of VOC. For moderate and above

ozone nonattainment areas, this

includes emission control requirements

for NSR and RACT.

The portions of section 182(f)(1)

relevant to St. Louis provide that the

stationary source NOX requirements

shall not apply where either of the

following tests are met:

(1) in any area, the net air quality

benefits are greater without the NOX

reductions from the sources concerned;

or

(2) in an ozone nonattainment area,

additional NOX reductions would not

contribute to ozone attainment in the

nonattainment area.

Section 182(f)(2) of the Act states that

the application of the NOX emission

reduction requirements may be limited

to the extent necessary to avoid excess

reductions of NOX.

The main tests for a NOX emissions

control exemption under EPA policy are

discussed in a December 1993 EPA

guidance, Guideline for Determining the

Applicability of Nitrogen Oxides

Requirements under Section 182(f). This

guidance was issued by the Office of Air

Quality Planning and Standards of the

EPA. This guidance notes that the EPA

has determined, based on a review of

the Act, that the excess reduction

demonstration for a NOX emissions

control exemption, under either a

‘‘contribute to attainment’’ test or a ‘‘net

ozone benefits’’ test, must be tied to an

area’s ozone attainment demonstration

SIP. For the reasons described in

Chapter 6 of the EPA guidance

document, the excess reductions must

be those NOX emission reductions in

excess of the NOX emission reductions

specified as being necessary for

attainment in the attainment

demonstration. The approval of the

excess emissions reduction petition

must be contingent on the final approval

of the ozone attainment demonstration.

Details of the current EPA policy

regarding NOX emission control

exemptions and transportation

conformity is contained in a November

14, 1995 final rule (60 FR 44790)

amending the transportation conformity

requirements. The final transportation

conformity rule requires consistency

with NOX motor vehicle emission

budgets in control strategy SIPs

regardless of whether a NOX control

exemption has been granted. Areas must

establish NOX emission budgets unless

the State’s modeled attainment

demonstration shows that NOX

emissions can essentially grow without

limit due to new federally funded

activities or federal actions without

threatening attainment of the ozone

standard.

Approval of a NOX emissions control

exemption would provide a basis for

eliminating the requirement to comply

with the transportation conformity

rule’s build/no-build test and less-than1990 test for NOX. The current Illinois

submittal, however, does not request an

exemption from transportation

conformity NOX requirements. In

addition, it should be noted that after an

area receives approval to use a motor

vehicle emissions budget for the

purposes of conformity determinations,

the use of a build/no-build test or a lessthan-1990 emissions test is no longer

pertinent. Therefore, an exemption from

NOX requirements for the build/nobuild test and less-than-1990 emissions

test is not necessary once an area’s

motor vehicle emissions budget is

approved (or found adequate) for use in

transportation conformity

determinations. The EPA is proposing

the approval of Illinois’ motor vehicle

emissions budget in this document.

The requirements for exemption from

the NOX control requirements of general

conformity relevant to Illinois’ request

are found in section 182(f)(2) of the Act.

Since section 182(f)(2) NOX control

exemptions are based on a

demonstration of ‘‘excess emission

reductions,’’ a NOX control exemption

cannot be granted unless the State has

made a clear showing through the ozone

attainment demonstration that the

emission reductions are indeed excess

(that the attainment demonstration does

not rely on such emission reductions)

20410 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

or, where NOX emission increases (due

to new federally-funded activities or

federal actions) are expected to result

from source growth due to an activity

for which the NOX control exemption is

sought, that NOX emissions can

essentially increase without limit and

still not cause ozone standard

violations. Note that activities that are

subject to conformity generally involve

emission increases rather than emission

decreases. For transportation conformity

determinations, consistency with the

motor vehicle emissions budget is the

means for ensuring that increases in

such emissions do not threaten

attainment of the ozone standard. In

contrast to transportation conformity,

however, general conformity

determinations are not based on

consistency with an explicitly identified

emissions budget, since quite often the

SIP does not create such budgets for the

emissions-generating activities that are

subject to general conformity.

Consequently, a NOX control exemption

for general conformity cannot be granted

under section 182(f)(2) of the Act unless

the State has otherwise clearly

demonstrated that NOX emissions can

essentially increase without limit and

still provide for attainment of the ozone

standard.

The situation for NSR, under section

182(f)(2) of the Act, is analogous. Unless

the State has otherwise clearly

demonstrated that NOX emissions can

essentially increase without limit due to

new or modified major stationary

sources, the NOX control exemption for

NSR cannot be approved. A policy

memorandum, ‘‘Scope of Nitrogen

Oxides (NOX) Exemptions,’’ dated

January 12, 1995, and signed by G.T.

Helms, Group Leader, Ozone/Carbon

Monoxide Programs Branch, EPA,

explains that, where EPA grants a NOX

exemption under the ‘‘excess

reductions’’ provision, the exemption

makes sense with respect to RACT but

not necessarily with respect to NSR. The

distinction would be that RACT

emissions impacts are exclusively

emission reductions, whereas NSR

impacts often involve emission

increases. It should be noted that NOX

new source requirements in ozone

nonattainment areas would revert to

Prevention of Significant Deterioration

(PSD) requirements (PSD allows

emission increases, but only at a

controlled rate) if an area is granted an

exemption from NSR NOX requirements.

Therefore, a NSR NOX control

exemption request, under section

182(f)(2), must be supported by a

demonstration that NOX emissions due

to new or modified major stationary

sources can essentially increase in an

area without limit and not cause ozone

standard violations.

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?

Illinois and Missouri have made the

following submittals, which in whole or

in part concern the ozone attainment

demonstration, a partial NOX control

exemption for the Illinois portion of the

St. Louis ozone nonattainment area, and

an extension of the attainment date for

the St. Louis ozone nonattainment area:

(a) In a submission dated November

10, 1999, the Missouri Department of

Natural Resources (MDNR) submitted an

ozone attainment demonstration along

with several additional proposed SIP

revisions. The additional SIP revisions

included:

i. Regulations and associated

documentation for the control of VOC

emissions from: aerospace manufacture

and rework facilities; volatile organic

liquid storage; wood furniture

manufacturing operations; batch process

operations; reactor processes and

distillation operations processes in the

synthetic organic chemical

manufacturing industry; and existing

major sources;

ii. Regulations and associated

documentation for the control of NOX

emissions intended to meet NOX RACT

requirements of the Act in the Missouri

portion of the St. Louis nonattainment

area;

iii. A 15 percent rate-of-progress plan

for the control of VOC emissions in the

Missouri portion of the St. Louis area;

and

iv. An improved vehicle inspection

and maintenance program.

The review of these additional SIP

revisions is the subject of separate

technical support documents and

rulemakings. See 65 FR 8094, 65 FR

8060, 65 FR 8092, 65 FR 8097, and 65

FR 8083, February 17, 2000. Only the

ozone attainment demonstration

portions of the submittal are considered

here;

(b) On November 15, 1999, the IEPA

submitted a letter outlining the ozone

attainment strategy for the St. Louis area

and the State’s emission control

commitments;

(c) On January 19, 2000, the MDNR

submitted an additional supplement to

the ozone attainment demonstration.

This supplement reflects revised

modeling which was performed at the

recommendation of EPA to include

future emission control measures in the

St. Louis area, including Missouri’s NOX

RACT program, emission control

contingency measures implemented by

both States, and additional VOC RACT

controls implemented by Missouri. The

revised analysis also incorporates other

emission inventory corrections based on

quality assurance activities conducted

by both States; and

(d) On February 10, 2000, the IEPA

submitted its adopted ozone attainment

demonstration SIP. This SIP revision

submittal includes a petition for an

exemption from NOX RACT, NOX NSR,

and general conformity NOX

requirements for the Illinois portion of

the St. Louis ozone nonattainment area.

This SIP revision also reflects the

emission modifications and attainment

demonstration revisions contained in

MDNR’s January 19, 2000 submittal.

When Were the Submittals Addressed

in Public Hearings, and When Were the

Submittals Formally Adopted by the

States?

The MDNR held a public hearing on

the attainment demonstration on

October 28, 1999, and the Missouri Air

Conservation Commission (MACC)

adopted the attainment demonstration

on November 8, 1999.

The IEPA held a public hearing on the

attainment demonstration on November

15, 1999. A subsequent public hearing

on the updated ozone attainment

demonstration was not held. It must be

noted, however, that the updated ozone

attainment demonstration did not

include additional emission controls in

Illinois beyond those addressed in the

November 15, 1999 public hearing.

What Modeling Approach Was Used in

the Analyses?

Illinois and Missouri cooperatively

conducted the modeling analyses and

other analyses used to support the

attainment demonstration. The

modeling approach is documented in

both Illinois’ February 10, 2000 ozone

attainment demonstration and in

Missouri’s November 10, 1999 ozone

attainment demonstration submittal.

Additional modeling analyses and

weight-of-evidence analyses are

addressed in Missouri’s January 19,

2000 supplemental modeling submittal.

The heart of the modeling system and

approach is the Urban Airshed Model—

Version V (UAM–V), developed

originally for application in the Lake

Michigan area, but now applied in many

other areas. This model was applied to

a large grid system (referred to as Grid

M) covering much of the upper

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20411

Midwest. Grid M was selected to cover

many of the ozone precursor emission

sources believed to affect the Lake

Michigan area and the St. Louis area.

Grid M was nested inside of a larger grid

system covering the eastern half of the

United States (the larger grid system

includes areas referred to as the ‘‘coarsegrid states’’ in the OTAG process used

to assess ozone transport in the eastern

United States and the impacts of

possible emission control measures to

generally reduce interstate ozone and

ozone precursor transport). The data

derived from the larger OTAG grid

provided air quality data for the

perimeter of Grid M. It should be noted

that for most of the attainment

considerations, the States considered

the peak ozone concentrations and

model performance for a sub-portion of

Grid M surrounding the St. Louis ozone

nonattainment area (the local modeling

domain). The conclusions discussed

later in this document were based on

data from this local modeling domain.

Besides being able to model ozone

and other pollutants in nested

horizontal grids, UAM–V can also

model individual elevated source

plumes within the modeling grid

(plume-in-grid or PiG). 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 States

provided regional and local emission

inventories, which were processed

through the Emissions Modeling

System—1995 version (EMS–95) to

prepare UAM–V emissions data input

files.

The initial emissions inventory files

were based on EPA’s NOX SIP call

emissions inventory. Substantial

revisions were made to the Missouri

point source and mobile source

inventories based on Missouri’s

comments on the NOX SIP call

emissions inventories (Missouri has also

made a number of additional attainment

year emission inventory changes as

documented in the January 19, 2000

submittal, discussed above). The State

submittals describe in detail the

procedures used to develop, and then

project, the base year emission

inventories to the 1995/1996 period and

to project emissions to account for

growth and control through 2003.

An important deviation from the NOX

SIP call inventory was the treatment of

biogenic emissions emanating from the

Ozark Mountain portion of Missouri.

Initial UAM–V modeling results had

indicated that biogenic emissions,

consisting primarily of isoprene from

oak trees, were overestimated in the

UAM–V model. This determination was

based on a recent study of biogenic

emissions and related VOC

concentrations in this area, referred to

as the Ozark Isoprene Experiment

(OZIE). Based on initial results from the

OZIE study, the Ozark biogenic

emissions predicted from the BEIS2

model have been adjusted downward 50

percent. Although the investigation of

the Ozark biogenics is not yet

completed, and the source of the

overestimation is not yet determined,

this gross adjustment to the inventory is

acceptable in this instance because there

is a general consensus between the

States and EPA that the UAM–V

modeling system clearly overestimates

isoprene in this area.

Meteorology: Meteorological inputs

for the UAM–V modeling system were

developed through prognostic

meteorological modeling (use of a set of

dynamic equations that describe

atmospheric motion and the distribution

and change of meteorological

parameters) using the RAMS3a

modeling system developed by Colorado

State University. A limited fourdimensional data assimilation was

performed for all days modeled.

RAMS3a output data were re-mapped to

the three-dimensional grid structure of

UAM–V.

The IEPA and MDNR have noted that

typically there are three types of

meteorological regimes associated with

high ozone concentrations in the St.

Louis nonattainment area. The first type

of episode occurs when a surface high

pressure system is centered to the east

of the St. Louis area along the Ohio and

Tennessee Valleys. This situation brings

southerly wind flow into the area. High

ozone in this situation is also associated

with high surface temperatures in the

upper 80’s and 90’s degrees Fahrenheit

(°F) range and with relatively low wind

speeds of less than 10 miles per hour.

Precipitation and cloud cover are

minimal.

The second type of high ozone

episode is due to stagnation conditions,

when surface winds are calm or with

wind speeds less than 5 miles per hour.

The wind direction is variable. The

temperatures are relatively high, in the

upper 80’s or lower 90’s.

The third type of episode occurs with

the approach of a frontal system from

the north. The front is generally weak

with little or no moisture and little or

no cloud cover. Temperature inversions

often form near the surface, trapping

pollutants near the surface and limiting

pollutant dispersion.

The following summarizes the

meteorology of the two episodes

modeled for the final attainment

demonstration:

July 16–19, 1991: On July 16, a

migratory high pressure system arrived

in central Pennsylvania producing light

southerly winds in the St. Louis area.

Hot, dry weather persisted during this

period, with temperatures reaching 90

°F in the St. Louis area. For the July 17

through July 19 period, winds in the St.

Louis area became southwesterly. Wind

speeds strengthened by July 19 as a cold

front approached from the northwest.

July 10–14, 1995: On July 10, a high

pressure system was centered over

Missouri, resulting in light and variable

winds across the St. Louis area. By July

11 and 12, the high pressure system

migrated eastward to the Tennessee

Valley. Winds in the St. Louis area were

southerly and peak temperatures were

in the mid to upper 90’s °F range. On

July 13 and 14, the conditions at the

surface remained the same with the high

pressure system centered near the East

Coast and dominating the meteorology

in the Eastern and Central United States.

Temperatures continued to peak in the

upper 90’s with relatively light

southerly winds.

The RAMS3a system was relatively

effective in modeling these

meteorological conditions.

Chemistry: Atmospheric chemistry

within the modeling grid system was

simulated using the Carbon BondVersion IV model developed by the

EPA.

Boundary and Initial Conditions: For

a 1996 base case evaluation, initial and

boundary conditions were derived from

extraction of data from a larger, 36

kilometer resolution OTAG coarse grid

over the grid cells marking the edges of

the Grid M domain. For the 2003

simulations, various NOX control levels

were applied in the coarse grid runs to

simulate the NOX impacts expected in

the various States. For States subject to

EPA’s NOX SIP call NOX emission

budgets (including the eastern third of

Missouri, but excluding the western

two-thirds of Missouri), NOX emission

rates for Electric Generating Units

(EGUs) were limited to 0.25 pounds per

mmBTU in the modeling system’s

emissions data. For the western twothirds of Missouri, an EGU NOX

emission rate of 0.35 pounds per

20412 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

6 In Michigan v. EPA, the U.S. Court of Appeals

for the District of Columbia generally upheld the

NOX SIP call, but remanded EPA’s determination to

require NOX reductions from the entire State of

Missouri. The Court explained that EPA had not

developed a sufficient record of evidence to support

requiring emissions reductions from the entire State

in light of modeling results that the OTAG

interpreted as indicating that emissions from the

western part of the State may not have a meaningful

impact on downwind nonattainment areas.

Michigan v. EPA, No. 98–1497 (D.C. Cir. March 3,

2000).

mmBTU was assumed.6 Only Actrequired NOX control levels and Actrequired VOC emission controls were

considered for States not subject to

EPA’s NOX SIP call (tightened EGU NOX

emission levels were not considered for

these States).

What High Ozone Periods Were

Modeled?

Three high ozone episodes, July 16–

19, 1991, July 10–14, 1995, and June 27–

29, 1996 were originally considered for

the attainment demonstration. The 1996

episode was subsequently dropped due

to unacceptable model performance.

In selecting the episodes to be

modeled, the States followed the

guidance provided by the EPA. The July

1991 ozone modeling guidance,

Guideline for Regulatory Application of

the Urban Airshed Model, recommends

that episodes for modeling be selected

to represent different meteorological

regimes observed to correspond with

ozone exceeding the standard. Both

stagnation and transport conditions

should be examined. A minimum of 3

primary episode days should be

modeled. Primary episode days are

those days for which ozone

concentrations exceeding the standard

were monitored in the area.

As noted in the discussion above, the

high ozone episodes Illinois and

Missouri selected and modeled have

covered more than 3 primary episode

days and have generally covered the

types of meteorology observed along

with high ozone in the St. Louis area.

What Procedures and Sources of

Projection Data Were Used To Project

the Emissions to Future Years?

To develop the attainment year (2003)

EGU emissions, the States initially

considered EPA’s 2007 base case

emissions developed for the NOX SIP

call. EPA developed these emissions

using the Integrated Planning Model

(IPM). The 2003 base case emissions

were developed from this assuming a

linear interpolation between the 1995/

1996 base period emissions and EPA’s

2007 base case emissions. A single

growth factor was developed for each

State to project the EGU emissions from

the 1995/1996 base period to the 2003

base case levels. Subsequent emission

control strategy tests altered the NOX

emission limits for these projected

source emissions.

For point source, non-EGU emissions,

the States projected the 1995/1996 base

period emissions to 2003 using BEA

projections of Gross State Product

(GSP). State-specific growth factors were

used for Illinois based on the use of the

Emissions Growth Analysis System

(EGAS), which replaced EPA-supplied

growth factors.

The 1995 stationary area and nonroad emission inventories were

projected to 2003 using BEA projections

of GSP. These projections include the

impacts of all applicable Clean Air Act

required controls. The projected nonroad emissions were adjusted to account

for certain federal emission control

requirements expected to be

implemented by 2003, including: the

federal small engine standards, Phase II;

federal marine engine standards (for

diesel engines of greater than 50

horsepower); federal locomotive

standards; and non-road diesel engine

standards.

Projections of on-road emissions from

1995/1996 to 2003 were accomplished

by projecting Vehicle Miles Traveled

(VMT) derived from the Highway

Performance Monitoring System

(HPMS) and by considering the VMT

growth estimates derived by the EPA

from the OTAG process. Travel demand

VMT estimates for 2003 were also

obtained for the St. Louis nonattainment

area from the East-West Gateway

Coordinating Council. The Illinois VMT

growth estimates reflect a growth rate of

2.0 percent per year, and the Missouri

VMT estimates reflect a growth of 23.5

percent between 1996 and 2003

(approximately 3 percent per year).

Future emission reductions for on-road

emissions were assumed to occur by

2003, including emission reductions

resulting from: national low emissions

vehicle standards; implementation of

improved vehicle inspection and

maintenance in the St. Louis

Metropolitan Statistical Area (MSA);

and reformulated gasoline in the

Missouri portion of the St. Louis MSA.

Biogenic emissions were assumed to

remain unchanged between 1995 and

2003.

All projected emissions were

processed through EMS–95 to provide

the emission inventory files for use in

UAM–V.

3. Modeling Results

How Did the States Validate the

Photochemical Modeling Results?

The States conducted a number of

statistical analyses to compare the

modeling system’s ozone predictions to

observed peak ozone concentrations for

the base period. Using the preliminary

base period emissions and

meteorological inputs, the States

derived statistics covering: unpaired

peak prediction accuracy; normalized

bias of data pairs; and gross errors of

data pairs for each of the modeled high

ozone episode days. These results were

compared to acceptable accuracy ranges

specified by the EPA. With a few

exceptions, the current modeling results

for the July 1991 and July 1995 episodes

are in agreement with EPA-specified

criteria. The results of the June 1996

episode modeling, however, did not

meet the EPA-specified criteria, and the

episode was, therefore, dropped from

further consideration.

Table 2 presents a summary of the

model performance statistics for the St.

Louis ozone nonattainment area. These

data were taken from Table 6.1 of

Illinois’ February 10, 2000 submittal.

TABLE 2.—MODEL OZONE PERFORMANCE STATISTICS ST. LOUIS NONATTAINMENT AREA

July 1991 July 1995

7/16 7/17 7/18 7/19 7/10 7/11 7/12 7/13 7/14

Observed (ppb) .............................................. 108 140 114 107 125 136 129 154 139

Modeled Base Year (ppb) .............................. 117 135 135 110 83 137 130 131 125

Normalized Bias (percent) ............................. ¥31.5 ¥9.7 ¥14.6 ¥2.5 ¥44.3 ¥8.9 ¥4.1 ¥16.3 ¥5.1

Gross Error (percent) ..................................... 33.1 30.6 28.0 19.9 45.6 32.3 26.1 23.7 23.0

Unpaired Peak Accuracy (percent) ................ 8.6 ¥3.4 18.6 2.9 ¥32.9 1.4 1.3 ¥14.6 ¥14.1

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20413

The model performance statistics can be

compared to EPA’s recommended (July

1991, Guideline for Regulatory

Application of the Urban Airshed

Model) acceptable model performance

statistics:

Normalized Bias: ±5 to 15 percent

Gross Error: 30 to 35 percent

Unpaired Peak Accuracy: ±15 to 20

percent.

It can be seen that the modeling

system does reasonably well and

performs within acceptable performance

ranges except for the leading days of the

modeled episodes (the leading days are

expected to exhibit poor model

performance and are generally dropped

from further consideration). The model

does under predict some peak ozone

levels, particularly on the highest ozone

days of July 17, 1991 and July 13–14,

1995. The model over predicts ozone

peaks on several other days, particularly

on July 18, 1991. Nonetheless, the

modeling system is judged to be

performing adequately and in an

acceptable manner to support emission

control strategy considerations.

It should be noted that the above

modeling statistics were derived using

base year emissions that did not include

the most recent emission revisions

derived for 1996. The States updated the

ozone modeling to incorporate the 2003

emission changes, but did not update

the modeling to incorporate the

emission changes for the 1996 base year.

The modeling performance statistics

were not determined to account for this

emissions revision. As explained later

in this document, the States must

update the modeling to include

emission changes in the 1996 base year

inventory and reconfirm that the plan

demonstrates attainment before the EPA

can approve the attainment

demonstration.

A number of other tests and

considerations were also given to the

overall model performance. The

performance evaluation considered the

following statistical and graphical

information:

• Tabular summary of model initial

and final base case performance

statistics;

• Comparison of the modeling output

to the conceptual model for each

episode;

• Spatial plots of peak daily and

hourly surface concentrations;

• Time series plots of hourly

concentrations for the monitors with the

highest ozone concentrations each day;

and

• Scatter plots of peak observed and

predicted ozone concentrations.

These tests and considerations point to

acceptable performance of the modeling

system for the base period.

The States also compared the

modeling results to a conceptual model

and found the modeling results to

comply with this conceptual model.

What Were the Ozone Modeling Results

for the Base Period and for the Future

Attainment Period?

The ozone modeling system was run

to simulate ozone concentrations on

selected high ozone days in 1991 and

1995 using emissions for a base year

(1996) and a future year (2003). The

resulting St. Louis area ozone peaks for

1996 and 2003 are given in Table 3.

Note that these modeled ozone peaks

reflect the corrected 2003 emissions and

modeling results as documented by

Missouri in its January 19, 2000

submittal and by Illinois in its February

10, 2000 submittal. The 1996 base year

modeled ozone concentrations do not

reflect the corrected 1996 emissions.

Therefore, the 1996 base year

predictions in Table 3 must be

reassessed following correction of the

base year modeling to reflect the

correction of the 1996 base year

emissions.

TABLE 3.—PEAK OBSERVED AND MODELED OZONE CONCENTRATIONS (PPB) IN THE ST. LOUIS OZONE NONATTAINMENT

AREA

Period

Date

July 1991 July 1995

7/17 7/18 7/19 7/11 7/12 7/13 7/14

Peak Observed ................................................................................................ 140 114 107 136 129 154 139

1996 Base Modeled ......................................................................................... 135 135 110 137 130 131 125

2003 Post-Control Modeled ............................................................................. 122 125 106 125 124 127 118

Do the Modeling Results Demonstrate

Attainment of the Ozone Standard?

As noted in Table 3, application of the

modeling system to the attainment year

emissions through a deterministic

approach does not demonstrate

attainment of the 1–hour standard

because 3 days are modeled to have

potential exceedances of the standard.

The application of the model in a

deterministic approach, as reflected in

this table, does not demonstrate

attainment of the standard.

The States also considered the

modeling results using a statistical

approach. A statistical approach, as

discussed in the June 1996 EPA

guidance, Guidance on Use of Modeled

Results to Demonstrate Attainment of

the Ozone NAAQS, permits some

modeled exceedances, based on the

severity (ozone conduciveness of a day’s

meteorology) of the modeled episode

days. Because the guidance leads to the

conclusion that none of the modeled

days were severe (as noted later, the

IEPA and the MDNR do believe that 3

of the days are severe based on daily

ozone maxima exceeding the area’s

ozone design value), the States

concluded that the statistical approach

could not be applied in this case.

Because the modeling fails to

explicitly demonstrate attainment of the

standard, the States considered

additional evidence coupled with the

results from the deterministic approach.

What Weight-of-Evidence Analyses and

Determinations Are Used To Support

the Modeled Attainment

Demonstration?

A weight-of-evidence determination

includes a subjective assessment of the

confidence one has in the modeled

results. The more extensive and credible

the corroborative information, the

greater the influence it has in permitting

deviations from the deterministic test’s

benchmark (modeled attainment at all

receptor locations for all days modeled).

As discussed in the June 1996 EPA

guidance, Guidance on Use of Modeled

Results to Demonstrate Attainment of

the Ozone NAAQS, the weight-ofevidence given to model results

depends on the following factors: (1)

Model performance; (2) confidence in

the underlying data bases; (3) length of

the projection period; and (4) how close

the results come to demonstrating

attainment for all receptor sites and

times modeled (see Table S.1. of the

June 1996 guidance for a complete list

of factors affecting weight-of-evidence

determinations and acceptance of model

20414 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

results nearly passing the attainment

tests).

The model performance and the

severity of the modeled episodes are of

particular note. Generally, the closer the

modeled results come to meeting the

deterministic test’s benchmark, the less

compelling other evidence supporting a

deviation from the benchmark needs to

be. Model results showing major

improvement in predicted ozone levels

can be used to support the acceptance

of the attainment demonstration.

The more extreme the days selected

for modeling (the more ozone conducive

the meteorology considered), the greater

the weight-of-evidence support that can

be attributed to modeling results

exceeding but nearly meeting the ozone

standard. Daily ozone maxima

exceeding an area’s ozone design value

is an acceptable surrogate for indicating

that these days are extreme. July 17,

1991 and July 13–14, 1995 are high

ozone days because the observed ozone

levels on those days are greater than the

area’s ozone design value (4th highest

daily maxima over 3 years).

Demonstrating attainment on these

extreme days implies greater ozone

improvements than the model is

predicting may be achieved. As noted

above, the 2003 post-control modeling

results are close to demonstrating

attainment, but continue to show

modeled exceedances on July 17, 1991,

July 11, 1995, and July 13, 1995. Since

the States believe that these days may be

considered to be extreme ozone days,

the States believe that some

consideration should be given to

weight-of-evidence determinations. The

observed July 11, 1995 peak observed

ozone concentration is at the level of the

area’s ozone design value, and,

therefore, IEPA and MDNR believe that

this day should also be considered to be

an extreme day, supporting the

consideration of weight-of-evidence

determinations. The EPA agrees that

July 17, 1991 and July 13, 1995 are

extreme ozone days and that this should

be considered when making the

determination. The EPA, however, does

not agree that July 11, 1995 is extreme,

since a day with a with a peak ozone

concentration at the area’s design value

is not considered to be extreme.

The States discussed, and the EPA

considered, the following factors and

data in aggregate in assessing whether

the States have provided sufficient

evidence to support the attainment

demonstration despite the modeled

exceedances of the ozone standard.

EPA’s decision was based on a

composite of the information, not on a

single element of the ‘‘weight-ofevidence.’’

Reduction of Predicted Exceedances:

Modeling for the 1996 base case showed

a total of 418 grid cell-hours that

exceeded the 1-hour ozone standard

during the 7 modeled days. For the 2003

post-control estimates, only 15 grid cellhours of exceedances were modeled.

This was determined to be a 97 percent

improvement in ozone air quality

relative to the 1-hour standard. The

States note that this improvement

exceeds the 80 percent improvement

criteria contained in one of the

benchmarks of EPA’s recommended

statistical attainment demonstration

approach. This finding suggests that the

attainment strategy will result in a

significant improvement in ozone air

quality.

Relative Reduction Factor Attainment

Test: The States applied a relative

reduction factor approach

recommended by the EPA for

addressing attainment of the 8-hour

ozone standard. (‘‘Use of Models and

Other Analyses in Attainment

Demonstrations for the 8-Hour Ozone

NAAQS,’’ Final Draft, Office of Air

Quality Planning and Standards, EPA,

April 1999.) In this approach, the

relative changes in ozone design values

for various monitoring sites are

determined using the relative changes in

ozone concentrations predicted by the

modeling system in the vicinity of these

monitoring sites. All predicted future

design values for the attainment year

must be less than 125 ppb to support the

attainment demonstration.

The States based the relative

reduction factor approach on the ozone

design values at monitoring sites for the

1995–1997 period. The relative

reduction factors (actually ozone

adjustment factors of 1 minus the

modeled fractional ozone changes due

to emission changes) were determined

from the 1996 and 2003 modeling

results. Based on these analysis values,

the results in Table 4 were obtained.

TABLE 4.—RELATIVE REDUCTION FACTOR RESULTS

Monitor locations 1-Hour design values

1995–1997

Ozone adjustment

factor

Future design values

State County (ppb)

Illinois .................................................................... Madison ................................................................ 128 0.91 116

St. Clair ................................................................. 108 0.92 99

Missouri ................................................................. Jefferson ............................................................... 125 0.98 122

St. Charles ............................................................ 131 0.92 120

St. Louis ............................................................... 119 0.98 116

The States believe that the relative

reduction factor analysis demonstrates

that attainment of the ozone standard is

likely in 2003 because all of the

resulting future design values as shown

in Table 4 are below the ozone standard.

However, this analysis reflects modeling

results for 1996 based on emissions

subsequently revised by the States. As

noted above, the 1996 modeling was not

revised to reflect the subsequent change

in 1996 emissions, whereas the 2003

post-control modeling was revised to

reflect emission changes. This

discrepancy has led to biased modeling

results. This analysis must be revisited

once the 1996 base year modeling is

corrected to reflect the corrected 1996

base year emissions.

EPA Additional Emission Reductions

Calculation: At the request of the EPA,

the States also applied an additional

emission reductions calculation as

described in the EPA guideline

document, Guidelines for Improving

Weight-of-Evidence Through

Identification of Additional Emission

Reductions, Not Modeled. This method

also uses an ozone adjustment factor

approach to project a monitored ozone

design value to an attainment year level.

This method is based on the use of an

area-wide maximum design value and

an ozone adjustment factor based on

relative changes in modeled peak ozone

concentrations within and downwind of

the nonattainment area. If the projected

design value is greater than or equal to

125 ppb, this method also leads to

estimates of additional VOC and NOX

emission reductions needed beyond the

selected/modeled control strategy to

attain the ozone standard. If the

projected design value is less than or

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20415

equal to 124 ppb, this result supports

the attainment demonstration.

To obtain the base design value, the

States averaged the area-wide design

values for four 3-year periods, 1993–

1995, 1994–1996, 1995–1997, and 1996–

1998. This was done to account for the

fact that the base period emissions cover

both 1995 and 1996. The design value

periods considered contained both of

these years. The averaging of these

design values also provides a more

robust estimate of a base design value

and addresses changes in meteorology.

The base ozone design value was

determined to be 133.5 ppb.

The ozone adjustment factor was

determined by averaging the modeled

area-wide peak ozone concentrations for

the local modeling domain for 1996 and

2003 and taking the ratio of these

averages, 2003 to 1996. An ozone

adjustment factor of 0.932 was

determined using this procedure.

The base ozone design value and the

ozone adjustment factor lead (133.5 ppb

multiplied by 0.932) to a future design

value of 124.4 ppb. This result, while

preliminary, shows that the control

strategy is adequate to achieve the ozone

standard. This determination, however,

must be reassessed once the 1996 base

year modeling is repeated to reflect the

corrected 1996 base year emissions.

Trends Analyses: The MDNR and

IEPA have determined or estimated the

emission trends for the St. Louis

nonattainment area for the years of 1990

through 2003 for both VOC and NOX.

The emission trends are plotted in

Figures 7.1 and 7.2 of IEPA’s February

10, 2000 attainment demonstration

submittal. The trends exhibit a

significant decrease in VOC and NOX

emissions within the St. Louis

nonattainment area since 1990.

Emissions of NOX and VOC are

expected to continue to decline through

2003 due to both State and federal

emission control requirements. This

includes the impacts of the States’ 15

percent Rate-Of-Progress plans,

implementation of VOC RACT in both

States, implementation of NOX RACT in

Missouri, title IV (Clean Air Act) acid

rain control requirements for EGUs, new

vehicle I/M programs in both Illinois

and Missouri, and reformulated gasoline

use.

The States have considered air quality

trends for 1977 through 1998.

Significant downward trends in peak

ozone levels have occurred since the

early 1980s. The trend in peak ozone

levels, however, have leveled off at

above-standard levels in the last few

years. Nonetheless, the States also note

the improvement in air quality relative

to the number of days per year

considered to be meteorologically

conducive to high ozone formation. The

States compared the trend of the

number of exceedance days per year to

the number of conducive days per year

for 1977 through 1998. The number of

conducive days was determined by

estimating the number of days with

meteorology meeting the following

parameters: (1) Maximum temperatures

exceeding 85 degrees Fahrenheit; (2)

wind speeds less than 10 miles per

hour; (3) solar radiation exceeding 500

Langleys; (4) little or no precipitation;

and (5) winds from the southeast to

west. The number of exceedance days

per year relative to the number of

conducive days per year was found to

decline significantly over the years. This

downward trend is believed to be due

to the implementation of emission

controls.

The States have also considered the

trend in background ozone

concentrations for 1989 through 1998.

Background ozone concentrations,

reflecting ozone transport into the St.

Louis area rather than local ozone

impacts, have been found to trend

upward over the most recent years

(1992–1998), pointing to the need to

control ozone transport. This ozone

transport is believed, based on the

ozone modeling, to play a significant

role in the ozone standard exceedances

in the St. Louis ozone nonattainment

area.

Analyses of regional NOX emissions

from Illinois, Indiana, Kentucky,

Missouri, Ohio, and Tennessee and

outside of the St. Louis ozone

nonattainment area shows an upward

trend over the period of 1985 through

1997, with 1997 total NOX emissions

being 16 percent higher than in 1985.

Illinois and Missouri note that the

upward trend in upwind regional NOX

emissions corresponds to the trend in

increased background ozone

concentrations. This observation lends

credence to the selected control strategy

of controlling regional NOX emissions.

The States’ analyses of air quality and

emission trends do provide some

support for the States’ attainment

demonstration. Progress in air quality

improvement through the current period

(1997–1999) is demonstrated and future

progress in air quality improvement is

shown to be likely. In addition, these

analyses lend support to a regional NOX

reduction as a reasonable approach to

achieving attainment of the ozone

standard. Nonetheless, the air quality

and emission trends by themselves do

not provide an adequate weight-ofevidence determination and do not

demonstrate that the ozone standard

will be attained by 2003. They simply

demonstrate that the States have made

progress towards attaining the standard

and are expected to continue to make

such progress.

EPA’s NOX SIP Call Modeling: The

States note that the EPA recommends

that States use the results of EPA’s NOX

SIP call modeling as part of the weightof-evidence for the ozone attainment

demonstrations. Based on the NOX SIP

call modeling, the post-control St. Louis

area maximum ozone design value is

projected to be 124 ppb at the St.

Charles County monitoring site in 2007

(subsequent modeling, incorporating

additional emission improvements

expected to result from Tier II vehicle

emission standards and the use of lowsulfur gasoline, indicates even lower

ozone levels in the St. Louis area in

2007). It should be noted, however, that

the NOX SIP call modeling considered

NOX emission controls that go beyond

the level of NOX controls contained in

the States ozone attainment strategy.

The NOX SIP call modeling supports the

direction of controls in the States’

control strategy (emphasis on regional

NOx controls).

Since the NOX SIP call will lead to

lower ozone levels in the St. Louis area

than the States’ selected emission

control strategy, EPA believes that this

is additional evidence in support of the

States’ attainment demonstration. As

noted above, the deterministic approach

failed to unequivocally demonstrate

attainment of the 1-hour standard. The

modeling employed by the States

assumed NOX emission limits higher

than those that were assumed in the

development of the NOX SIP call

(regional NOX control levels of 0.25

pounds/mmBTU for EGUs in the States’

attainment demonstration versus 0.15

pounds/mmBTU for EGUs along with

other regional NOX controls in the NOX

SIP call). As a consequence, the NOX

SIP call will produce lower ozone

transport levels than the control strategy

submitted by the States. As noted above,

in Michigan v. EPA, the U.S. Court of

Appeals for the District of Columbia

generally upheld the NOX SIP call, but

remanded EPA’s determination to

require NOX emission reductions from

the entire State of Missouri. Michigan v.

EPA, No. 98–1497 (D.C. Cir. March 3,

2000). Since sensitivity analyses have

shown that lower ozone interstate

transport levels result in lower peak

ozone levels in the St. Louis area, we

expect the implementation of the NOX

SIP call to result in greater improvement

in the ozone levels than predicted in the

States’ attainment demonstration

modeling, which only assumed NOX

emission limits of 0.25 pounds per

mmBTU for EGUs in upwind States.

20416 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

7 Illinois will also need to adopt controls as

necessary to respond to the NOX SIP call.

This factor lends support to the States’

attainment demonstration and supports

the view that the combination of NOX

SIP call controls and the emission

controls selected by the States should

bring the St. Louis area into attainment

of the 1-hour ozone standard.

4. Emission Control Strategies

What Emission Control Strategies Were

Considered in the Attainment

Demonstration?

Illinois’ emission control strategy

relies on the Clean Air Act emission

control requirements through 2003,

including the impacts of the State’s 15

percent Rate-Of-Progress (ROP) plan for

the Illinois portion of the St. Louis

ozone nonattainment area, federal

emission controls expected to be

implemented by 2003, and a statewide

NOX emission limit of 0.25 pounds/

mmBTU for EGUs of generating capacity

greater than 25 MWe. The NOX emission

limit for EGUs only applies during the

ozone season (May 1 through September

30). Illinois is in the process of

developing state-wide NOX emission

control regulations to cover this NOX

limit. Further, it must be noted that

Illinois has committed to tighten this

NOX limit even further if required to

attain the ozone standard in the Lake

Michigan area. Illinois is also assessing

the impacts of regional NOX controls on

ozone transport into the Lake Michigan

area, where Illinois must also attain the

1-hour standard. If modeling indicates

that EGU NOX emission limits must be

tightened beyond 0.25 pounds/mmBTU

to attain the ozone standard in Lake

Michigan area, Illinois is committed to

completing rule development to achieve

the more stringent NOX emission limits.

If more stringent NOX emission limits

are adopted, this will further lower

ozone levels in the St. Louis area. At

minimum, the State will adopt an EGU

NOX emission limit of 0.25 pounds/

mmBTU regardless of the modeling

outcome for the Lake Michigan area.7

Missouri’s emission control strategy

also relies on the Clean Air Act

emission control requirements through

2003, including impacts of the State’s 15

percent ROP plan, and regional NOX

emission limits for EGUs. The NOX

emission limits are differentiated

between two portions of the State, with

a NOX emission limit of 0.25 pounds/

mmBTU in the eastern third of the State

and a NOX emission limit of 0.35

pounds/mmBTU in the western twothirds of the State. 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 Missouri’s November 10,

1999 submittal above); NOX RACT in

the Missouri portion of the St. Louis

ozone nonattainment area; and an

improved vehicle I/M program.

The emissions control strategy also

assumes that all other States in the ‘‘fine

grid’’ area of the OTAG analysis (those

States subject to NOX emission budgets

in EPA’s NOX SIP call) would also limit

NOX emissions from EGUs to 0.25

pounds/mmBTU. Again note that this

differs from the EGU NOX emission rate

of 0.15 pounds/mmBTU considered for

these sources in EPA’s NOX SIP call and

considered by EPA to be acceptable for

background ozone considerations.

Illinois and Missouri believe that these

States should be assumed to implement

NOX emission limits no tighter than

those considered for Illinois and

Missouri in the attainment

demonstration and has reflected such

thinking in the attainment

demonstration. Nonetheless,

implementation of the NOX SIP call will

further lower ozone levels in the St.

Louis area, adding weight-of-evidence

and a margin of safety to the States’

attainment demonstration.

Have the States Adopted the Selected

Emission Control Strategies and Have

the States Adopted the Emission Control

Regulations Needed To Implement the

Emission Control Strategies?

The States have adopted the emission

control strategies and all associated

emission control regulations except the

state-wide NOX emission limits for

EGUs. Both States are expected to

complete development of proposed NOX

emission control regulations for the

EGUs by mid-2000 and have final

adopted rules no later than December

2000. Note that the EPA would not

finally approve the attainment

demonstration until after it has

determined that the statewide NOX

control regulations are acceptable.

Missouri submitted additional

emission control regulations needed to

implement the control strategy with the

November 10, 1999 submittal. These

regulations include NOX RACT,

additional VOC RACT, and the

regulations required to implement the

State’s 15 percent rate-of-progress plan.

These regulations are undergoing

separate review and have been proposed

for approval as noted elsewhere in this

document.

Illinois has completed all VOC

emission control regulations and has

submitted these regulations to the EPA.

All of these VOC emission control

regulations have been previously

approved by the EPA.

Have the States Adopted all Emission

Control Regulations Required by the

Clean Air Act?

Illinois and Missouri have adopted all

VOC emission control requirements

required under the Clean Air Act for a

moderate ozone nonattainment area. As

noted above, some of these emission

control regulations are currently under

review by the EPA. The final approval

of the ozone attainment demonstration

is contingent on the final approval of

these regulations.

As noted above, the States have yet to

complete the regional, statewide NOX

emission control regulations needed to

complete the ozone control strategy.

Final approval of the attainment

demonstration is contingent on the

adoption of these rules. In the

alternative, this proposed rulemaking

proposes to disapprove the ozone

attainment demonstration if the States

fail to submit the proposed regional,

statewide NOX control regulations by

June 2000 and final adopted regional,

statewide NOX control regulations by

December 2000. The attainment

demonstration will also not be finally

approved if the EPA review of the

regional NOX emission control

regulations, which will be the subject of

a separate rulemaking, concludes that

they are not approvable.

5. Transportation Conformity

Did the States Address Transportation

Conformity in the Submittals and Did

the States Adopt Motor Vehicle

Emission Budgets?

Both Illinois and Missouri have

submitted motor vehicle emissions

budgets for the 2003 attainment year in

their respective portions of the St. Louis

ozone nonattainment area. These

emission budgets must meet the

adequacy criteria in the Transportation

Conformity Rule before the budgets and

the attainment demonstration are

approved.

The IEPA has submitted an emissions

budget of 28.70 tons per day for VOC

and 40.64 tons per day for NOX in the

Illinois portion of the nonattainment

area (the Metro-East area). This budget

has been posted to the EPA web site for

public comment and has been under

adequacy review since its submittal to

the EPA. The EPA review of this

emissions budget has found that the

budget meets all of the adequacy criteria

in section 93.118 of the Transportation

Conformity Rule. These criteria include:

(1) The SIP was endorsed by the

Governor (or his designee) and was

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20417

subject to a State public hearing; (2)

consultation among federal, State, and

local agencies occurred; (3) the

emissions budget is clearly identified

and precisely quantified; (4) the motor

vehicle emissions budget, when

considered together with all other

emissions, is consistent with

attainment; and (5) the motor vehicle

emissions budget is consistent with and

clearly related to the emissions

inventory and control strategy in the

submitted attainment demonstration.

The EPA is also required to consider

comments submitted to the State at the

public hearing. No comments were

received by the State on the

transportation conformity budgets. Also,

no comments were received on the

Illinois budget during the adequacy

posting.

The EPA is proposing in this

document to approve the transportation

conformity budget submitted by Illinois.

Comments on this proposed approval

should be submitted to the docket as

outlined in the comments section of this

document.

The MDNR included an emissions

budget in its November 10, 1999

submittal. An error in the emission

estimates was subsequently detected

during the interagency consultation

process. The MDNR is revising the

motor vehicle emissions budget, which

will be addressed in subsequent EPA

rulemaking. The new Missouri motor

vehicle emissions budget will be posted

on EPA’s adequacy web site (go to http:/

/www.epa.gov/otaq/traq/ and click on

‘‘conformity,’’ then click on ‘‘adequacy

web pages’’) when it is received.

As noted elsewhere in this document,

Missouri must submit a final motor

vehicle emissions budget which the

EPA can determine to be adequate for

conformity assessments (Illinois has

already met this requirement) to avoid

disapproval of the attainment

demonstration SIP. Consistent with the

schedule for submission of revisions to

the States’ attainment demonstration,

described previously in this document,

Missouri must submit any proposed

revisions to its motor vehicle emissions

budget no later than June 30, 2000.

Although these emissions budgets are

undergoing separate adequacy review, it

should be noted that the ozone

attainment demonstration will not be

given a final approval until the EPA has

determined these emissions budgets to

be adequate to support future

transportation conformity reviews.

6. Petition for NOx Control Exemption

The February 10, 2000, IEPA

submittal contains a petition for an

exemption from NOx emission reduction

requirements that are contained in

section 182(f)(1) of the Act. The IEPA

requests that this exemption apply to

the RACT, NSR, and general conformity

NOx requirements for the Illinois

portion of the St. Louis nonattainment

area pursuant to section 182(f)(2) of the

Act. This exemption is based on Illinois’

assertion that it has demonstrated

attainment of the ozone standard

without the need to account for these

NOx emission controls. Therefore,

Illinois contends that these NOx

emission controls must be considered to

be ‘‘excess’’ and subject to an exemption

under section 182(f)(2) of the Act.

Illinois believes that the ozone

attainment demonstration provides the

requisite technical support for this

petition. The NOx emission reductions

in the attainment demonstration and

control strategy in Illinois are limited to

the NOx emission reductions from EGUs

or other Act-required emission controls

not subject to this petition. Illinois

contends (Missouri has not made a

similar argument) that the ozone

impacts in the St. Louis area resulting

from NOx emissions are dominated by

the impacts of regional NOx emissions

from EGUs, and that controlling local

NOx emissions for other source

categories would not significantly

impact ozone levels. Illinois believes

that it has shown in the ozone

attainment demonstration modeling that

application of the specific section 182(f)

NOx control requirements would not

meaningfully contribute to attainment of

the ozone standard. Review of the

modeling documentation supplied to

the EPA, however, does not show the

specific impacts of NOx RACT, NOx

NSR, or NOx general conformity. The

modeling documentation does imply

that Illinois applied no specific

emission reduction credits for these NOx

control measures.

It should be noted that Missouri has

adopted NOX RACT regulations for the

St. Louis area and is not 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 Missouri

portion of the St. Louis nonattainment

area.

B. Environmental Protection Agency

Review of the Submittals

1. Adequacy of the States’

Demonstrations of Attainment

Did the States Adequately Document the

Techniques and Data Used to Derive the

Modeling Input Data and Modeling

Results?

The submittals from the States

thoroughly 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 States’

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 meet the requirements of EPA’s

July 1991 and June 1996 ozone

modeling guidelines.

Do the Weight-of-Evidence

Determinations Support the Attainment

Demonstration?

The weight-of-evidence

determinations, when viewed in

aggregate, show that the demonstration

of attainment may be adequate for

proposed approval. An issue, however,

must be taken with several critical

portions of the weight-of-evidence

determinations, namely with the

relative reduction factor results and the

additional emission reductions

calculation. As noted above, MDNR

revised the emission inventories for

2003. Based on these emission

inventory revisions, the modeling for

2003 was revised. Such a modeling

revision, however, was not performed

for 1996 despite that fact that the 1996

emissions should also be revised. This

may have resulted in a modeling bias in

the results of the 2003 ozone estimates

relative to those of 1996 as modeled.

This has led to errors in the estimation

of relative reduction factors and,

therefore, may potentially impact the

predicted future ozone design value for

the area.

Comparison of 2003 attainment

demonstration emissions as submitted

in Illinois’ draft October 15, 1999

attainment demonstration with the 2003

attainment demonstration emissions as

documented in the February 10, 2000

submittal shows that the nonattainment

area VOC emissions have been

20418 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

decreased by approximately 60 tons per

day and that the nonattainment area

NOX emissions have been increased by

approximately 6 tons per day. These

emission changes incorporate both post1996 emission reductions as well as

changes in emission factors and

calculation procedures. It is the changes

in emission factors and calculation

procedures that would also apply to the

1996 emissions. From the data

provided, it is impossible to determine

the magnitude of the emission changes

that would have to be applied to the

1996 emissions. Again, this may

potentially impact the predicted future

design value, which is a key component

of the weight-of-evidence argument.

Accordingly, the States must revise the

ozone modeling for 1996 using the

updated 1996 emissions and must

reassess the results for the relative

reduction factor calculations and the

additional reductions test.

It is inappropriate to conclude at this

time that the demonstration of

attainment has fallen short or that the

selected emission control strategy is

inadequate. The States are being given

an opportunity to reassess the 1996

modeling results and the associated

relative reduction predictions. It is not

expected to take more than a few

months for the States to perform this

analysis. If the reassessment of

modeling results causes the States to

significantly modify the attainment

strategy, the EPA will re-propose

rulemaking on attainment

demonstration SIP revisions, and will

seek new public comments on the

revised SIP revisions.

2. Adequacy of the Emission Control

Strategies

Do the Emission Control Strategies Meet

the Requirements of the Clean Air Act?

Given the data presented, the selected

emission control strategy may be

adequate to achieve attainment of the 1-

hour ozone standard. However, due to

the need to reassess the weight-ofevidence determination, the EPA

reserves final judgement on the

emissions control strategy until after it

has had an opportunity to review the

revised 1996 ozone modeling results

and the revised weight-of-evidence

determinations (the revised relative

reduction factor estimates and the

revised additional reductions test

results).

Do Emission Control Shortfalls Exist

With Regard To Probable Attainment of

the Ozone Standard?

To determine whether there is a

shortfall in emission controls, the need

for revised 1996 base year modeling

must first be addressed. Corrections to

the 1996 base year emissions inventory

will result in changes to the predicted

daily maxima which are presented in

Table 3. Again, the EPA can not fully

approve the attainment demonstration

or act on the attainment date extension

request until these analyses have been

completed and demonstrate attainment

of the standard consistent with the Act

and EPA policy.

Have the States Specified and Adopted

Acceptable Motor Vehicle

Transportation Conformity Budgets?

The States have submitted motor

vehicle transportation conformity

emission budgets. The budget submitted

by the IEPA for Illinois portion of the St.

Louis nonattainment area has been

found to meet the adequacy criteria and

is proposed for approval. The budget

submitted by the MDNR needs to be

revised and resubmitted. The attainment

demonstration will not be approved

until adequate motor vehicle emissions

budgets are submitted and determined

to be adequate. The EPA is proposing in

the alternative to disapprove the

attainment demonstration if Missouri

does not submit the motor vehicle

emissions budget in accordance with

the schedule specified above.

3. Adequacy of the Requests for

Extension of the Attainment Date

The policy for the extension of an

ozone attainment date is discussed

above. The States’ compliance with

these requirements is discussed here.

a. Identification of the Area as a

Downwind Area Affected by Ozone

Transport

The States have cited EPA’s NOX SIP

call modeling and analyses documented

in the OTAG process to demonstrate

that the St. Louis ozone nonattainment

area is affected by an upwind area in

another State that significantly

contributes to ozone nonattainment in

St. Louis. Kentucky is the State outside

of Illinois and Missouri that contributes

to ozone concentrations in the St. Louis

area. On December 17, 1999, EPA took

final action on petitions from 8

northeastern States under section 126 of

the Act. In its action, EPA granted those

portions of the petitions for sources for

which it made affirmative technical

determinations with respect to the 1-

hour ozone standard. These included

sources in Kentucky that make

significant contributions to ozone levels

in the St. Louis area. In addition, Illinois

and Missouri have noted the trend

towards increasing transport of ozone

into the area from upwind States.

The EPA proposes to find that the

States’ demonstration of ozone transport

meets the criteria in EPA’s attainment

date extension policy.

b. Submittal of an Approvable

Attainment Demonstration

EPA’s review of the attainment

demonstration shows that, with the

required changes EPA has specified, it

is likely to be approved. In addition, the

States have adopted the emission

control measures (RACT, I/M, and other

15 percent Rate-Of-Progress plan

requirements) or are expected soon to

adopt the necessary emission control

measures (regional NOX emission

controls) needed to achieve attainment.

c. Adoption of all Applicable Local

Measures Required Under the Area’s

Current Ozone Classification

Missouri has completed the adoption

of all local measures required by the Act

for the area’s current classification.

Illinois has adopted the necessary local

measures, with the exception of NOX

RACT. If EPA approves Illinois’ request

for an exemption from the NOX RACT

requirements, as discussed elsewhere in

this document, this element will have

been met.

Both States must adopt and submit

regional NOX regulations to complete

the requirements for the attainment SIP.

Proposed regional NOX regulations are

expected to be developed by June 2000

and final regional NOX regulations must

be adopted and submitted by December

2000.

EPA concludes that the States are

likely to meet this requirement. It is

noted, however, that the final

determination on this issue must wait

until all necessary rules, and the NOX

RACT exemption request, have been

approved by the EPA.

d. Implementation of all Adopted

Measures by the Time Upwind Controls

are Expected.

In anticipation of the implementation

of upwind regional NOX controls in

2003 (the NOX SIP call requires

implementation of NOX controls by May

15, 2003), Illinois and Missouri selected

this year as the new attainment period

for the St. Louis area in keeping with

EPA’s attainment date extension policy.

Both States have committed to fully

implement the regional NOX controls by

2003 (these NOX emission controls must

be implemented prior to the start of the

ozone season in 2003) and are expected

to have implemented the other control

measures prior to that date. Therefore,

the States have met or will meet this

condition.

Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules 20419

The EPA concludes that, at the

present time, the States are likely to

meet the conditions for an attainment

date extension and are in the process of

concluding efforts to meet these

conditions. Final resolution of this

issue, however, will not occur until the

States have corrected the noted problem

with the attainment demonstration and

have adopted the required regional NOX

regulations.

EPA believes that it is likely that

Illinois and Missouri will be able to

meet the criteria for obtaining an

attainment date extension under the

conditions contained in EPA’s July 16,

1998 attainment date extension policy.

If this occurs, the attainment date for the

St. Louis area is proposed to be

extended to November 15, 2003. Even

though the regional NOX controls will

be implemented by the start of the

ozone season in 2003, this later

attainment date recognizes that the

States’ attainment demonstration does

consider other VOC and NOX emission

reductions that will continue to occur

throughout the ozone season in 2003.

If the States do not correct the

attainment demonstration, do not adopt

approvable regional NOX emission

control regulations, or otherwise fail to

meet the conditions of the attainment

date extension policy, EPA will take

final action on the proposed

reclassification described in EPA’s

March 18, 1999 document (64 FR

13384). To the extent that comments

received on the March 18, 1999

document, and 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. Adequacy of the NOX Control

Exemption Request has Illinois

Adequately Supported its Request for an

Exemption From the Requirement for

NOX emission Control Regulations?

The IEPA has requested an exemption

from additional NOX RACT, NSR, and

general conformity requirements under

section 182(f) of the Clean Air Act based

on its contention that the selected

emissions control strategy leads to

attainment of the ozone standard

without these additional NOX emission

reductions or NOX emission control

measures in the Illinois portion of the

nonattainment area. Review of the

attainment demonstration against EPA’s

NOX exemption policy discussed above

shows that the request for a NOX control

exemption may be granted in part. NOX

RACT emission reductions in the

Illinois portion of the nonattainment

area are not needed for attainment of the

1-hour ozone standard, based on the

current modeled ozone attainment

demonstration. Illinois, however, will

need to show that its request for a NOX

RACT exemption is still supportable

after the States revise the 1996 base year

modeling and show that the emissions

control strategy selected still results in

attainment without assuming NOX

RACT for Illinois sources. Since NOX

RACT clearly impacts NOX emissions

through NOX emission reductions and

the attainment demonstration, as it

currently exists, does not rely on these

types of NOX emission reductions in the

Illinois portion of the St. Louis

nonattainment area, Illinois has

demonstrated that a NOX RACT

exemption is justified under section

182(f)(2) of the Act. Although NOX

RACT would lead to NOX emission

reductions, possibly leading to further

ozone reductions, Illinois has

demonstrated that additional local NOX

emission reductions in the Illinos

portion of the nonattainment area are

not needed to demonstrate attainment of

the ozone standard in the St. Louis area.

Section 182(f)(2) of the Act gives

States the flexibility to limit application

of the NOX control requirements to the

extent that any portion of these

emission reductions are demonstrated to

result in ‘‘excess reductions.’’ In this

case, the modeling of the adopted

emission control strategy demonstrates

that application of NOX RACT in the

Illinois portion of the nonattainment

area would result in NOX emission

reductions in excess of those needed to

attain the ozone standard. Therefore,

these emission reductions are not

required.

As noted above, the support for a NOX

control exemption pursuant to section

182(f)(2) of the Act must be based on a

demonstration that NOX emissions can

essentially increase without limit

without causing ozone standard

violations. The State has failed to make

such a demonstration. Therefore, EPA

believes that a NOX control exemption

for NSR and general conformity

pursuant to section 182(f)(2) (an ‘‘excess

emissions reduction’’ argument) is not

supported and proposes to disapprove

the request relative to these Clean Air

Act requirements.

III. Proposed Action

The EPA proposes to approve the

Illinois and Missouri ozone attainment

demonstrations for the St. Louis ozone

nonattainment area. In the alternative,

the EPA is proposing to disapprove the

ozone attainment demonstrations if

Illinois or Missouri do not revise the

attainment demonstration modeling and

associated weight-of-evidence analyses

to incorporate corrections to the 1996

base year emissions inventory and

confirm that attainment is

demonstrated. These revisions must be

submitted in proposed form by June 30,

2000 and in final form by December 31,

2000. In addition, EPA is proposing to

disapprove the ozone attainment

demonstrations if: (1) the States do not

submit proposed regional, statewide

NOX emission control regulations for

electric generating units by June 2000 or

do not adopt and submit regional,

statewide NOX emission control

regulations for electric generating units

by December 2000; and (2) Missouri

does not submit a proposed motor

vehicle emissions budget for VOC and

NOX by June 30, 2000 and final

revisions to the motor vehicle emissions

budget by December 31, 2000. The

Environmental Protection Agency

proposes to: (1) approve an exemption

from NOX emission control

requirements for NOX RACT for the

Illinois portion of the St. Louis ozone

nonattainment area; (2) approve an

extension of the ozone attainment date

for the St. Louis ozone nonattainment

area to November 15, 2003; and (3)

approve the transportation conformity

motor vehicle emissions budget

submitted by Illinois for the Illinois

portion of the St. Louis ozone

nonattainment area. The EPA proposes

to disapprove Illinois’ requested

exemption from NOX emission control

requirements for New Source Review

and general conformity for the Illinois

portion of the St. Louis ozone

nonattainment area.

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

20420 Federal Register / Vol. 65, No. 74 / Monday, April 17, 2000 / Proposed Rules

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

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 costeffective 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: March 30, 2000.

Gail C. Ginsberg,

Acting Regional Administrator, Region 5.

Dated: April 7, 2000.

Dennis Grams,

Regional Administrator, Region 7.

[FR Doc. 00–9393 Filed 4–14–00; 8:45 am]

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