60318 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

ENVIRONMENTAL PROTECTION

AGENCY

40 CFR Part 52

[FRL–5911–7]

Finding of Significant Contribution and

Rulemaking for Certain States in the

Ozone Transport Assessment Group

Region for Purposes of Reducing

Regional Transport of Ozone

AGENCY: Environmental Protection

Agency (EPA).

ACTION: Notice of proposed rulemaking

(NPR).

SUMMARY: In accordance with the Clean

Air Act (CAA), today’s action is a

proposed rulemaking to require certain

States to submit State implementation

plan (SIP) measures to ensure that

emission reductions are achieved as

needed to mitigate transport of ozone

(smog) pollution and one of its main

precursors—emissions of oxides of

nitrogen (NOX)— across State

boundaries in the eastern half of the

United States. The States affected by

today’s action are in the Ozone

Transport Assessment Group (OTAG)

Region.

Today’s action proposes to find that

the transport of ozone from certain

States in the OTAG region (the 37

eastern most States and the District of

Columbia) significantly contributes to

nonattainment of the ozone national

ambient air quality standards (NAAQS),

or interferes with maintenance of the

NAAQS, in downwind States. This

proposal explains the basis for

determining significant contribution or

interference with maintenance for the

affected States. Further, by today’s

action, EPA is proposing the appropriate

levels of NOX emissions that each of the

affected States will be required to

achieve.

The EPA is committed to promulgate

final action on the proposed rule within

12 months from the date of publication

of today’s action.

DATES: The EPA is establishing a 120-

day comment period, ending on March

9, 1998. For additional information on

the comment period, please refer to

SUPPLEMENTARY INFORMATION. A public

hearing will be held during the

comment period, if requested. If a

public hearing is requested, EPA will

make an announcement in the Federal

Register.

ADDRESSES: Documents relevant to this

matter are available for inspection at the

Air and Radiation Docket and

Information Center (6101), Attention:

Docket No. A–96–56, U.S.

Environmental Protection Agency, 401

M Street SW, room M–1500,

Washington, DC 20460, telephone (202)

260–7548, between 8:00 a.m. and 4:00

p.m., Monday through Friday, excluding

legal holidays. A reasonable fee may be

charged for copying. Comments and

data may also be submitted

electronically by following the

instructions under SUPPLEMENTARY

INFORMATION of this document. No

Confidential Business Information (CBI)

should be submitted through e-mail.

FOR FURTHER INFORMATION CONTACT:

General questions concerning today’s

action should be addressed to Kimber

Smith Scavo, Office of Air Quality

Planning and Standards, Air Quality

Strategies and Standards Division, MD–

15, Research Triangle Park, NC 27711,

telephone (919) 541–3354. Please refer

to SUPPLEMENTARY INFORMATION below

for a list of contacts for specific subjects

described in today’s action.

SUPPLEMENTARY INFORMATION:

Comment Period

Because commenters may wish to

submit technical information that may

require additional time to develop, EPA

will accept additional pertinent

information beyond the 120-day time

frame and will do what is possible to

take the information into account for the

final rulemaking. The EPA will make

every effort to consider this information.

However, due to the time frames

associated with this action, EPA cannot

guarantee that information submitted

after the close of the comment period

will be considered. The EPA is

committed to publish the final

rulemaking within 12 months of the

date of today’s action.

Electronic Availability

The official record for this

rulemaking, as well as the public

version, has been established under

docket number A–96–56 (including

comments and data submitted

electronically as described below). A

public version of this record, including

printed, paper versions of electronic

comments, which does not include any

information claimed as CBI, is available

for inspection from 8 a.m. to 4 p.m.,

Monday through Friday, excluding legal

holidays. The official rulemaking record

is located at the address in ADDRESSES

at the beginning of this document.

Electronic comments can be sent

directly to EPA at: A-and-RDocket@epamail.epa.gov. Electronic

comments must be submitted as an

ASCII file avoiding the use of special

characters and any form of encryption.

Comments and data will also be

accepted on disks in WordPerfect in 5.1

file format or ASCII file format. All

comments and data in electronic form

must be identified by the docket number

A–96–56. Electronic comments on this

proposed rule may be filed online at

many Federal Depository Libraries.

Availability of Related Information

Documents related to OTAG are

available on the Agency’s Office of Air

Quality Planning and Standards’

(OAQPS) Technology Transfer Network

(TTN) Bulletin Board System (BBS). The

telephone number for the TTN BBS is

(919) 541–5742. To access the bulletin

board a modem and communications

software are necessary. The following

parameters on the communications

software are required: Data Bits-8;

Parity-N; and Stop Bits-1. The

documents are located on the OTAG

BBS. The TTN can also be accessed via

the web at http://www.epa.gov/ttn. If

assistance is needed in accessing the

system, call the help desk at (919) 541-

5384 in Research Triangle Park, NC.

Other documents related to OTAG can

be downloaded from OTAG’s webpage

at http://www.epa.gov/ttn/otag. The

OTAG’s technical data are located at

http://www.iceis.mcnc.org/OTAGDC.

For Additional Information

For technical questions related to the

determination of significant

contribution, please contact Norm

Possiel, Office of Air Quality Planning

and Standards, Emissions, Monitoring,

and Analysis Division, MD–13,

Research Triangle Park, NC 27711,

telephone (919) 541–5692. For legal

questions, please contact Howard

Hoffman, Office of General Counsel, 401

M Street SW, MC–2344, Washington,

DC, 20460, telephone (202) 260–5892.

For questions concerning the statewide

emission budgets, please contact Doug

Grano, Office of Air Quality Planning

and Standards, Air Quality Strategies

and Standards Division, MD–15,

Research Triangle Park, NC 27711,

telephone (919) 541–3292. For questions

concerning SIP approvability, please

contact Carla Oldham, Office of Air

Quality Planning and Standards, Air

Quality Strategies and Standards

Division, MD–15, Research Triangle

Park, NC 27711, telephone (919) 541–

3347. For questions concerning the cost

analysis, please contact Sam

Napolitano, Office of Atmospheric

Programs, MC–6201J, 401 M Street SW,

Washington, DC 20460, telephone (202)

233–9751.

Outline

I. Preamble
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60319

A. Summary of Rulemaking and Affected

States

B. General Factual Background

C. Statutory and Regulatory Background

1. Clean Air Act Provisions

a. 1970 and 1977 Clean Air Act

Amendments

b. 1990 Clean Air Act Amendments

i. 1-hour Ozone NAAQS

ii. Revised Ozone NAAQS

iii. Provisions Concerning Transport of

Ozone and Its Precursors

2. Regulatory Structure

a. March 2, 1995 Policy

b. OTAG

c. EPA’s Transport SIP Call Regulatory

Efforts

d. Revision of the Ozone NAAQS

e. Impacts of NOX Emissions

D. EPA’s Proposed Analytical Approach

1. Process for Requiring Submission of

Section 110(a)(2)(D) SIP Revisions

2. Overview of Elements of Section

110(a)(2)(D)

a. Summary of Section 110(a)(2)(D)

b. Significant Contribution to

Nonattainment

c. Interfere with Maintenance

d. Remedying the Significant Contribution

i. Adequate Mitigation

ii. Elimination of Contribution

iii. Comparison of the Two Legal

Interpretations of Section 110(a)(2)(D)

iv. Other Issues

e. Control Implementation and Budget

Attainment Dates

E. Section 126 Petitions

F. OTAG Process

II. Weight of Evidence Determination of

Significant Contribution

A. Introduction

B. Background Technical Information

1. OTAG Modeling Process

2. OTAG Strategy Modeling

3. OTAG Geographic Modeling

4. Other Relevant Analyses

C. Technical Analyses of Significant

Contribution

1. Criteria for Determining Significant

Contribution

2. Overview of Technical Approach

3. Identification of Ozone ‘‘Problem Areas’

4. Analysis of Air Quality, Trajectory, and

Non-OTAG Modeling Information

5. Approaches for Analyzing Subregional

Modeling Data

a. Approaches for 1-Hour Nonattainment

b. Approaches for 8-Hour Nonattainment

c. Methods for Presenting 1-Hour and 8-

Hour Assessments

6. Contributions to 1-Hour Nonattainment

7. Contributions to 8-Hour Nonattainment

8. Assessment of State Contributions

D. Comparison of Upwind and Downwind

Contributions to Nonattainment and

Costs of Controls

III. Statewide Emissions Budgets

A. General Approach for Calculating

Budgets

1. Overview

2. Relationship of Proposed Budget

Approach to the OTAG

Recommendations

3. Uniform Application of Control

Measures

a. OTAG

b. Collective Contribution and Equity

Considerations

c. Modeling Assumptions and Potential

Synergistic Effects

d. Electrical Generation and Emissions

Shifting

e. Alternative Approaches Based on NonUniform Application of Control

Measures

4. Seasonal vs Annual Controls

5. Consideration of Areas with CAA

Section 182(f) NOX Waivers

6. Relation of OTC NOX MOU to Budgets

in the Ozone Transport SIP Rulemaking

B. Budget Development Process

1. Overview

2. Description of and Rationale for

Proposed Control Assumptions

a. Considering the Cost Effectiveness of

Other Actions

b. Determining the Cost Effectiveness of

NOX Controls

c. Summary of Measures Assumed in

Proposed Budget Calculation

3. Proposed Assumptions for Electric

Utilities

a. Affected Entities

b. Methodology Used to Determine the

Proposed Electric Utility Budget

Component

i. Proposed Utility Budget Component

Calculation and Alternatives

ii. Seasonal Utilization

iii. Growth Considerations

c. Summary and Proposed Utility Budget

Components

4. Proposed Assumptions for Other

Stationary Sources

a. Affected Entities

b. Methodology Used to Determine the

Proposed Area and Nonutility Point

Source Budget Components

c. Summary and Proposed Area and

Nonutility Point Source Budget

Components

5. Proposed Assumptions for Highway

Vehicles

a. Affected Entities

b. Methodology Used to Develop the

Proposed Highway Vehicle Budget

Component

i. Budget Component Determination

Method and Alternatives Considered

ii. Activity Level Projections and Growth

Considerations

iii. Seasonal/Weekday/Weekend

Adjustment

iv. Comparison to OTAG

Recommendations

c. Summary and Proposed Highway

Vehicles Budget Components

d. Conformity

6. Proposed Assumptions for Nonroad

Sources

a. Affected Entities

b. Methodology Used to Determine the

Proposed Nonroad Budget Component

i. Budget Component Determination

Method and Alternatives Considered

ii. Activity Level Projections and Growth

Considerations

iii. Seasonal/Weekday/Weekend

Adjustment

iv. Comparison to OTAG

Recommendations

c. Summary and Proposed Nonroad Budget

Components

C. State-by-State Emissions Budgets

D. Recalculation of Budgets

IV. Implementation of Revised Air Quality

Standards

A. Introduction

B. Background

C. Implementation Policy

1. Areas Eligible for the Transitional

Classification

2. Areas Not Eligible for the Transitional

Classification

V. SIP Revisions and Approvability Criteria

A. SIP Revision Requirements and

Schedule

B. SIP Approval Criteria

1. Budget Demonstration

2. Control Strategies

a. Enforceable Measures Approach

b. Fixed Tonnage Budgets

3. Control Strategy Implementation

4. Growth Estimates

5. Promoting End-Use Energy Efficiency

C. Review of Compliance

D. 2007 Reassessment of Transport

E. Sanctions

1. Failure to Submit

2. Failure to Implement

F. Federal Implementation Plans (FIPs)

1. Legal Framework

2. Timing of FIP Action

3. Statewide Emissions Budgets

4. FIP Control Measures

5. FIP Trading Program

6. Section 105 Grants

G. Other Consequences

VI. States Not Covered by This Rulemaking

VII. Model Cap-and-Trade Program

VIII. Regulatory Analysis

IX. Air Quality Analyses

X. Nonozone Benefits of NOX Reductions

XI. Impact on Small Entities

XII. Unfunded Mandates Reform Act

Appendix A—References

Appendix B—OTAG Recommendations

Appendix C—Tables for Section II. Weight of

Evidence

Determination of Significant Contribution

Appendix D—Figures for Section II. Weight

of Evidence

Determination of Significant Contribution

I. Preamble

A. Summary of Rulemaking and

Affected States

The CAA has set forth many

requirements to address nonattainment

of the ozone NAAQS. Many States have

found it difficult to demonstrate

attainment of the NAAQS due to the

widespread transport of ozone and its

precursors. The Environmental Council

of the States (ECOS) recommended

formation of a national work group to

allow for a thoughtful assessment and

development of consensus solutions to

the problem. This work group, OTAG,

was established 2 years ago to undertake

an assessment of the regional transport

problem in the Eastern half of the

United States. The OTAG was a

collaborative process conducted by

representatives from the affected States,

EPA, and interested members of the
60320 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

public, including environmental groups

and industry, to evaluate the ozone

transport problem and develop

solutions. The OTAG region includes

the following 37 States and the District

of Columbia: Alabama, Arkansas,

Connecticut, Delaware, District of

Columbia, Florida, Georgia, Illinois,

Indiana, Iowa, Kansas, Kentucky,

Louisiana, Maine, Maryland,

Massachusetts, Michigan, Minnesota,

Mississippi, Missouri, Nebraska, New

Hampshire, New Jersey, New York,

North Carolina, North Dakota, Ohio,

Oklahoma, Pennsylvania, Rhode Island,

South Carolina, South Dakota,

Tennessee, Texas, Vermont, Virginia,

West Virginia and Wisconsin. Today’s

action builds on the work of OTAG.

Through the OTAG process, the States

concluded that widespread NOX

reductions are needed in order to enable

areas to attain and maintain the ozone

NAAQS. The EPA believes, based on

data generated by OTAG and other data

sources, that certain downwind States

receive amounts of transported ozone

and ozone precursors that significantly

contribute to nonattainment in the

downwind States. Today’s action

proposes SIP requirements under

section 110(a)(1) and section 110(k)(5)

in order to meet the requirements of

section 110(a)(2)(D) to prohibit ozone

precursor emissions from sources or

activities in those States from

‘‘contribut(ing) significantly to

nonattainment in, or interfer(ing) with

maintenance by,’’ a downwind State of

the ozone NAAQS.

Upon this determination, the EPA is

requiring SIP revisions in order to take

steps toward ensuring that the necessary

regional reductions are achieved that

will enable current ozone

nonattainment areas in the eastern half

of the United States to prepare

attainment demonstrations and that will

enable all areas to demonstrate

noninterference with maintenance of

the ozone standard.

The OTAG’s July 8, 1997 final

recommendations (see Section I.F.

OTAG Process and Appendix B)

identify control measures for States to

achieve additional reductions in

emissions of NOX and do not identify

such measures for volatile organic

compounds (VOC) beyond EPA’s

promulgation of national VOC

measures. The OTAG Regional and

Urban Scale Modeling and Air Quality

Analysis Work Groups reached the

following relevant conclusions:

• Regional NOX emissions reductions

are effective in producing ozone

benefits; the more NOX reduced, the

greater the benefit.

• VOC controls are effective in

reducing ozone locally and are most

advantageous to urban nonattainment

areas. (See Appendix B).

The EPA agrees with these OTAG

conclusions and, thus, is not proposing

new SIP requirements for VOC

emissions for the purpose of reducing

the interstate transport of ozone. States

may, however, need to consider

additional reductions in VOC emissions

as they develop local plans to attain and

maintain the ozone standards.

Therefore, this rulemaking is intended

to make a finding of significant

contribution to a nonattainment

problem, or interference with a

maintenance problem, and to assign,

specifically, the emissions budgets for

NOX that each of the identified States

must meet through SIP measures. As

indicated, the EPA is proposing to

require the submission of SIP controls to

meet the specified budgets. However,

this requirement permits each State to

choose for itself what measures to adopt

to meet the necessary emission budget.

Consistent with OTAG’s

recommendations to achieve NOX

emission decreases primarily from large

stationary sources in a trading program,

EPA encourages States to consider

electric utility and large boiler controls

under a cap-and-trade program as a costeffective strategy. This is described in

more detail in section III, Statewide

Emission Budgets. The EPA also

recognizes that promotion of energy

efficiency can contribute to a costeffective strategy. The EPA is working to

develop guidance on how States can

integrate energy efficiency into their

SIPs to help meet their NOX budgets at

least cost.

The EPA proposes to find, after

considering OTAG’s recommendations

and other relevant information, that the

following 22 States and the District of

Columbia significantly contribute to

nonattainment in, or interfere with

maintenance by, a downwind State:

Alabama, Connecticut, Delaware,

Georgia, Illinois, Indiana, Kentucky,

Massachusetts, Maryland, Michigan,

Missouri, North Carolina, New Jersey,

New York, Ohio, Pennsylvania, Rhode

Island, South Carolina, Tennessee,

Virginia, West Virginia, and Wisconsin.

These findings proposed today reflect

the air quality modeling and other

technical work done by OTAG, as well

as other relevant information.

Under this proposal, these States

would be required to adopt and submit,

within 12 months after publication of

the notice of final rulemaking, SIPs

containing control measures that will

mitigate the ozone transport problem by

meeting the assigned statewide

emissions budget. Section II, Weight of

Evidence Determination of Significant

Contribution, describes how EPA

determined which States to propose as

significant contributors, and section III,

Statewide Emission Budgets, describes

how EPA determined the appropriate

statewide emission budgets and

proposes to assign specific emission

budgets for the States identified above.

Section V, SIP Revisions and

Approvability Criteria, describes the

proposed SIP requirements.

The EPA believes that expedited

implementation of regional control

strategies to facilitate attainment is

necessary. On July 18, 1997, EPA

published its final rule for strengthening

the NAAQS for ozone by establishing a

new, 8-hour NAAQS (62 FR 38856).

This results in more areas and larger

areas with monitoring data indicating

nonattainment. Thus, it will be even

more critical to implement regional

control strategies which will mitigate

transport into areas in violation of the

new standard and thus enable these

areas to demonstrate attainment. The

regional NOX reduction strategy

proposed in today’s action will provide

a mechanism to achieve reductions that

will be necessary for States to enable

them to attain and maintain this revised

standard. The proposed regional

reductions alone should be enough to

allow most of the new nonattainment

counties in States covered by this

rulemaking to be able to comply with

the new standard. States that are not

required to comply with the

requirements set forth in today’s action

would also benefit from the NOX

strategy EPA is proposing if they adopt

similar measures. On July 16, 1997,

President Clinton issued a directive on

the implementation of the revised air

quality standards. This implementation

policy is described in section IV,

Implementation of Revised Air Quality

Standards.

Many of the States that EPA is not

proposing to find as significant

contributors to the ozone nonattainment

problem, and, therefore, do not have a

proposed NOX statewide emissions

budget to mitigate ozone transport, still

may need, as recommended by OTAG,

to cooperate and coordinate SIP

development activities with other

States. States with local interstate

nonattainment areas for the 1-hour

standard and/or the new 8-hour

standard are expected to work together

to reduce emissions to mitigate local

scale interstate transport problems in

order to provide for attainment in the

nonattainment area as a whole.

In addition, areas in these States

(those covered by OTAG modeling but
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60321

not covered by this proposal) may be

able to receive the transitional

classification as described in section IV,

Implementation of Revised Air Quality

Standards. An area in the State would

satisfy one of the eligibility

requirements for the transitional area

classification by attaining the 1-hour

standard and submitting a SIP

attainment demonstration by 2000 for

the 8-hour standard. The OTAG’s

modeling (in particular, OTAG strategy

Run 5 described in section II.B.2, OTAG

Strategy Modeling) shows that a strategy

in which a State adopted NOX emission

decreases similar to those EPA proposes

to establish in this rulemaking would be

helpful in achieving attainment in most

of these areas. The EPA strongly

suggests that these States (those covered

by OTAG modeling but not covered by

this proposal) with new nonattainment

counties for the 8-hour standard should

consider the option of this strategy since

our analysis indicates that nearly all

new nonattainment counties are

projected to come into attainment as a

result of this strategy. The benefits of

this regional strategy for States not

required to implement the proposed

strategy under this rulemaking are

described below in section VI, States

Not Covered by this Rulemaking.

The EPA plans to publish a

supplemental notice of proposed

rulemaking (SNPR) in early 1998. The

Agency intends to include in the SNPR

a proposed model cap-and-trade rule,

air quality analyses of the proposed

statewide emission budgets, emissions

reporting and State reporting

requirements, a discussion of the

interaction with the Title IV NOX rule

(including EPA’s plans to proceed with

rulemaking on remanded elements of

that rule relating to flexible

implementation where an appropriate

cap-and-trade system is in place), and

proposed rule language for the

rulemaking discussed in today’s action.

There will be another public comment

period following publication of the

SNPR. All comments received regarding

either today’s action or the proposed

rule language in the SNPR will be

considered before promulgation of a

final rule.

B. General Factual Background

In today’s proposal, EPA takes a

significant step in order to reduce ozone

in the eastern half of the country.

Ground-level ozone, the main harmful

ingredient in smog, is produced in

complex chemical reactions when its

precursors, VOC and NOX, react in the

presence of sunlight. The chemical

reactions that create ozone take place

while the pollutants are being blown

through the air by the wind, which

means that ozone can be more severe

many miles away from the source of

emissions than it is at the source.

At ground level, ozone can cause a

variety of ill effects to human health,

crops and trees. Specifically, groundlevel ozone induces the following health

effects:

• Decreased lung function, primarily

in children active outdoors.

• Increased respiratory symptoms,

particularly in highly sensitive

individuals.

• Hospital admissions and emergency

room visits for respiratory causes,

among children and adults with preexisting respiratory disease such as

asthma.

• Inflammation of the lung.

• Possible long-term damage to the

lungs.

The new 8-hour primary ambient air

quality standard will provide increased

protection to the public from these

health effects.

Each year, ground-level ozone above

background is also responsible for

several hundred million dollars worth

of agricultural crop yield loss. It is

estimated that full compliance of the

newly promulgated ozone NAAQS will

result in about $500 million of

prevented crop yield loss. Ozone also

causes noticeable foliar damage in many

crops, trees, and ornamental plants (i.e.,

grass, flowers, shrubs, and trees) and

causes reduced growth in plants.

Studies indicate that current ambient

levels of ozone are responsible for

damage to forests and ecosystems

(including habitat for native animal

species).

The science of ozone formation,

transport, and accumulation is complex.

Ozone is produced and destroyed in a

cyclical set of chemical reactions

involving NOX, VOC and sunlight.

Emissions of NOX and VOC are

necessary for the formation of ozone in

the lower atmosphere. In part of the

cycle of reactions, ozone concentrations

in an area can be lowered by the

reaction of nitric oxide with ozone,

forming nitrogen dioxide; as the air

moves downwind and the cycle

continues, the nitrogen dioxide forms

additional ozone. The importance of

this reaction depends, in part, on the

relative concentrations of NOX, VOC

and ozone, all of which change with

time and location.

As part of the efforts to reduce

harmful levels of smog, EPA today

proposes to require certain States to

revise their SIPs in order to implement

the regional reductions in transported

ozone and its precursors that are needed

to enable areas in the Eastern United

States to attain and maintain the

NAAQS. Since air pollution travels

across county and State lines, it is

essential for State governments and air

pollution control agencies to cooperate

to solve the problem.

C. Statutory and Regulatory Background

1. Clean Air Act Provisions

a. 1970 and 1977 Clean Air Act

Amendments. For almost 30 years,

Congress has focused major efforts on

curbing tropospheric ozone. In 1970,

Congress amended title I of the CAA to

require, among other things, that EPA

issue, and periodically review and if

necessary revise, NAAQS for ubiquitous

air pollutants (sections 108 and 109).

Congress required the States to submit

SIPs to attain those NAAQS, and

Congress included, in section 110, a list

of minimum requirements that SIPs

must meet. Congress anticipated that

areas would attain the NAAQS by 1975.

In 1977, Congress amended the CAA

to provide, among other things,

additional time for areas to attain the

ozone NAAQS, as well as to impose

specific SIP requirements for those

nonattainment areas. These provisions

first required the designation of areas as

attainment, nonattainment, or

unclassified, under section 107; and

then required that SIPs for ozone

nonattainment areas include the

additional provisions set out in part D

of title I, as well as demonstrations of

attainment of the ozone NAAQS by

either 1982 or 1987 (section 172).

In addition, the 1977 Amendments

included two provisions focused on

interstate transport of air pollutants: the

predecessor to current section

110(a)(2)(D), which requires SIPs for all

areas to constrain emissions with

certain adverse downwind effects; and

section 126, which authorizes a

downwind State (or political

subdivision) to petition for EPA to

impose limits directly on upwind

sources found to adversely affect that

State. Section 110(a)(2)(D), which is key

to the present action, is described in

more detail below.

b. 1990 Clean Air Act Amendments.

In 1990, Congress amended the CAA to

better address, among other things,

continued nonattainment of the 1-hour

ozone NAAQS, the requirements that

would apply if EPA revised the 1-hour

standard, and transport of air pollutants

across State boundaries (Pub. L. 101–

549, Nov. 15, 1990, 104 Stat. 2399,

codified at 42 U.S.C. 7401–7671q).

Numerous provisions added, or revised,

by the 1990 Amendments are relevant to

today’s proposal.
60322 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

1 For moderate ozone nonattainment areas, the

attainment demonstration was due November 15,

1993 (section 182(b)(1)(A), except that if the State

elected to conduct an urban airshed model, EPA

allowed an extension to November 15, 1994.

2 In addition, section 115 authorizes EPA to

require a SIP revision when a State’s emitters

‘‘cause or contribute to air pollution which may

reasonably be anticipated to endanger public health

or welfare in a foreign country.’’

i. 1-hour Ozone NAAQS. In the 1990

Amendments, Congress required the

States and EPA to review and, if

necessary, revise the designation of

areas as attainment, nonattainment, and

unclassifiable under the ozone NAAQS

in effect at that time, which was the 1-

hour standard (section 107(d)(4)). Areas

designated as nonattainment were

divided into, primarily, five

classifications based on air quality

design value (section 181(a)(1)). Each

classification carries specific

requirements, including new attainment

dates (sections 181–182). In increasing

severity of the air quality problem, these

classifications are marginal, moderate,

serious, severe and extreme. The OTAG

region includes all classifications except

extreme.

As amended in 1990, the CAA

requires States containing ozone

nonattainment areas classified as

serious, severe, or extreme to submit

several SIP revisions at various times.

One set of SIP revisions included

specified control measures, such as

reasonably available control technology

(RACT) for existing VOC and NOX

sources (section 182(b)(2), 182(f)). In

addition, the CAA requires the

reduction of VOC in the amount of 15

percent by 1996 from a 1990 baseline

(section 182(b)(1)). Further, the CAA

requires the reduction of VOC or NOX

emissions in the amount of 9 percent

over each 3-year period from 1996

through the attainment date (the rate-ofprogress (ROP) SIP submittals) under

section 182(c)(2)(B). In addition, the

CAA requires a demonstration of

attainment (including air quality

modeling) for the nonattainment area

(the attainment demonstration), as well

as SIP measures containing any

additional reductions that may be

necessary to attain by the applicable

attainment date (section 182(c)–(e)). The

CAA established November 15, 1994 as

the required date for the ROP and

attainment demonstration SIP

submittals.1

ii. Revised Ozone NAAQS. Section

109(d) of the CAA requires periodic

review and, if appropriate, revision of

the NAAQS. As amended in 1990, the

CAA further requires designating areas

as attainment, nonattainment, and

unclassifiable under a revised NAAQS

(section 107(d)(1)). The CAA authorizes

EPA to classify areas that are designated

nonattainment under a new NAAQS,

and to establish for those areas

attainment dates not to exceed 10 years

from the date of designation (section

172(a)).

The CAA continues, in revised form,

certain requirements, dating from the

1970 Amendments, which pertain to all

areas, regardless of their designation.

All areas are required to submit SIPs

within certain time frames (section

110(a)(1)), and those SIPs must include

specified provisions, under section

110(a)(2). In addition, SIPs for

nonattainment areas are generally

required to include additional specified

control requirements, as well as controls

providing for attainment of the revised

NAAQS and periodic reductions

providing ‘‘reasonable further progress’’

in the interim (section 172(c)).

iii. Provisions Concerning Transport

of Ozone and Its Precursors. The 1990

Amendments reflect general awareness

by Congress that ozone is a regional, and

not merely a local, problem. As

described above, ozone and its

precursors may be transported long

distances across State lines to combine

with ozone and precursors downwind,

thereby exacerbating the ozone

problems downwind. In the case of

ozone, this transport phenomenon was

not generally recognized until relatively

recently. Yet, ozone transport is a major

reason for the persistence of the ozone

problem, notwithstanding the

imposition of numerous controls, both

Federal and State, across the country.

Section 110(a)(2)(D) provides one of

the most important tools for addressing

the problem of transport. This

provision, which applies by its terms to

all SIPs for each pollutant covered by a

NAAQS, and for all areas regardless of

their attainment designation, provides

that a SIP must contain provisions

preventing its sources from contributing

significantly to nonattainment problems

or interfering with maintenance in

downwind States.

Section 110(k)(5) authorizes EPA to

find that a SIP is substantially

inadequate to meet any CAA

requirement, as well as to mitigate

interstate transport of the type described

in section 184 (concerning ozone

transport in the northeast) or section

176A (concerning interstate transport in

general) and thereby require the State to

submit, within a specified period, a SIP

revision to correct the inadequacy. The

CAA further addresses interstate

transport of pollution in section 126,

which Congress clarified in 1990.

Subparagraph (b) of that provision

authorizes each State (or political

subdivision) to petition EPA for a

finding that emissions from ‘‘any major

source or group of stationary sources’’ in

an upwind State contribute significantly

to nonattainment in, or interfere with

maintenance by, the downwind State. If

EPA makes such a finding in support of

a section 126 petition, EPA would

impose limits on the affected source or

group of sources (section 126(c)).2

In addition, the 1990 Amendments

included specific provisions focused on

the interstate transport of ozone. Section

184 delineates a multistate ozone

transport region (OTR) in the Northeast,

requires specific additional controls for

all areas (not only nonattainment areas)

in that region, and establishes the Ozone

Transport Commission (OTC) for the

purpose of recommending to EPA

regionwide controls affecting all areas in

that region.

2. Regulatory Structure

a. March 2, 1995 Policy.

Notwithstanding significant efforts, the

States generally were not able to meet

the November 15, 1994 statutory

deadline for the attainment

demonstration and other SIP

submissions required under section

182(c). The major reason for this failure

was that States were not able to address

or control transport. As a result, in a

memorandum from Mary D. Nichols,

Assistant Administrator for Air and

Radiation, dated March 2, 1995, entitled

‘‘Ozone Attainment Demonstrations,’’

(March 2, 1995 Memorandum or the

Memorandum), EPA recognized the

efforts made by States and the

remaining difficulties in making the

ROP and attainment demonstration

submittals. The EPA recognized that

development of the necessary technical

information, as well as the control

measures necessary to achieve the large

level of reductions likely to be required,

had been particularly difficult for the

States affected by ozone transport.

Accordingly, as an administrative

remedial matter, the Memorandum

indicated that EPA would establish new

time frames for SIP submittals. The

Memorandum indicated that EPA would

divide the required SIP submittals into

two phases. Phase I generally consisted

of: SIP measures providing for ROP

reductions due by the end of 1999, an

enforceable SIP commitment to submit

any remaining required ROP reductions

on a specified schedule after 1996, and

an enforceable SIP commitment to

submit the additional SIP measures

needed for attainment. Phase II consists

of the remaining submittals, beginning

in 1997.

Ten States and the District of

Columbia failed to submit Phase I
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60323

elements within the specified time. By

notice dated July 10, 1996 (61 FR

36292), EPA issued findings and thereby

started sanctions clocks for these areas

for those Phase I submittals.

The Phase II submittals primarily

consisted of the remaining ROP SIP

measures, the attainment demonstration

and additional local rules needed to

attain, and any regional controls needed

for attainment by all areas in the region.

The March 2, 1995 Memorandum

indicated that the attainment

demonstration, target calculations for

the post-1999 ROP milestones, and

identification of rules needed to attain

and for post-1999 ROP were due in mid1997. To allow time for States to

incorporate the results of the OTAG

modeling into their local plans, EPA, in

its Final Policy for Implementation of

the 1-hour and Pre-Existing PM–10

Standards, is extending the mid-1997

submittal date to April 1998.

b. OTAG. In addition, the March 2

1995 Memorandum called for an

assessment of the ozone transport

phenomenon. The Environmental

Council of States (ECOS) had

recommended formation of a national

work group to allow for a thoughtful

assessment and development of

consensus solutions to the problem. The

OTAG has been a partnership between

EPA, the 37 easternmost States and the

District of Columbia, industry

representatives and environmental

groups. This effort has created an

opportunity for the development of an

Eastern United States ozone strategy to

address transport and to assist in

attainment of the 1-hour ambient ozone

standard.

The EPA believes that the OTAG

process has been invaluable in

demonstrating the types of regional

ozone precursor reductions that are

needed to enable areas in the Eastern

United States to attain and maintain the

ambient air quality standard for ozone.

Indeed, today’s action to propose to

mandate SIP revisions under section

110(a)(2)(D) is a first step directed at

providing the regulatory structure to

implement the kinds of broad regional

precursor reductions recommended by

OTAG.

c. EPA’s Transport SIP Call

Regulatory Efforts. Shortly after OTAG

began its work, EPA began to indicate

that it intended to issue a SIP call to

require States to implement the

reductions necessary to address the

ozone transport problem. On January 10,

1997 (62 FR 1420), EPA published a

Notice of Intent that articulated this goal

and indicated that before taking final

action, EPA would carefully consider

the technical work and any

recommendations of OTAG.

By a letter to Mary Gade, Chair of

OTAG, dated April 16, 1997, EPA

Assistant Administrator Mary D.

Nichols stated that on the basis of

technical work performed by EPA staff,

it appeared that EPA would issue a SIP

call to specified States and the District

of Columbia. The EPA staff issued a

technical support document,

‘‘Preliminary Assessment of States

Making a Significant Contribution to

Downwind Ozone Nonattainment,’’

dated April, 1997, which explained

EPA’s technical basis for those tentative

conclusions. Please refer to section II,

Weight of Evidence Determination of

Significant Contribution, for EPA’s

revised conclusions.

As described below in section I.F.,

OTAG Process, OTAG completed its

work in June 1997 and issued its final

recommendations to EPA on July 8,

1997. The OTAG’s technical work and

recommendations form part of the basis

of today’s proposal.

d. Revision of the Ozone NAAQS. On

July 18, 1997 (62 FR 38856), EPA issued

its final action to revise the NAAQS for

ozone. The EPA’s decision to revise the

standard was based on the Agency’s

review of the available scientific

evidence linking exposures to ambient

ozone to adverse health and welfare

effects at levels allowed by the preexisting 1-hour ozone standards. The 1-

hour primary standard was replaced by

an 8-hour standard at a level of 0.08

parts per million (ppm), with a form

based on the 3-year average of the

annual fourth-highest daily maximum 8-

hour average ozone concentration

measured at each monitor within an

area. The new primary standard will

provide increased protection to the

public, especially children and other atrisk populations, against a wide range of

ozone-induced health effects. Health

effects are described in section I.B,

General Factual Background. The EPA

retained the applicability of the 1-hour

NAAQS for certain areas to ensure

adequate health protection during the

transition to full implementation of the

8-hour NAAQS.

The pre-existing 1-hour secondary

ozone standard was replaced by an 8-

hour standard identical to the new

primary standard. The new secondary

standard will provide increased

protection to the public welfare against

ozone-induced effects on vegetation as

described in section I.B, General Factual

Background.

e. Impacts of NOX Emissions. At the

August 7, 1997 Clean Air Act Advisory

Committee meeting, EPA announced the

availability of a document (‘‘Nitrogen

Oxides: Impacts on Public Health and

the Environment,’’ EPA–452/R–97–002,

August 1997) that describes the multiple

impacts of NOX emissions on public

health and the environment and the

consequent implications for national

policy. In addition to helping attain

public health standards for ozone,

decreases in emissions of NOX are

helpful to reducing acid deposition,

greenhouse gases, nitrates in drinking

water, stratospheric ozone depletion,

excessive nitrogen loadings to aquatic

and terrestrial ecosystems, and ambient

concentrations of nitrogen dioxide,

particulate matter and toxics. These

impacts are described in more detail in

section X, Nonozone Benefits of NOX

Reductions.

D. EPA’s Proposed Analytical Approach

1. Process for Requiring Submission

of Section 110(a)(2)(D) SIP Revisions

As described above, SIPs for all areas

must meet the requirements of section

110(a)(2), including section 110(a)(2)(D),

which imposes limits on sources that

affect the ability of downwind areas to

attain and maintain the NAAQS.

Because many areas are currently

required to attain two ozone NAAQS—

the 1-hour standard and the 8-hour

standard—with different SIP planning

requirements, EPA proposes that section

110(a)(2)(D) be applied in different ways

with respect to each of the ozone

NAAQS.

Under the 1-hour ozone NAAQS, each

area is currently required to have a SIP

in place. Moreover, EPA has determined

that the 1-hour standard will continue

to apply to areas designated

nonattainment for the 1-hour NAAQS

until EPA determines that the area has

air quality meeting this standard (40

CFR 50.9(a) (62 FR 38894 (July 18,

1997)). Accordingly, each area is under

a current obligation to include in its SIP,

provisions that meet the requirements of

section 110(a)(2)(D) for the 1-hour

NAAQS.

This obligation to meet section

110(a)(2)(D) under the 1-hour standard

applies even after EPA determines that

an upwind area has attained the 1-hour

standard, and the applicability of that

standard thereby terminates for the

upwind area. Regardless of the status of

the 1-hour standard with respect to the

upwind area’s air quality, a downwind

area may continue to have a

nonattainment problem under the 1-

hour standard, and the upwind area’s

sources may continue to impact that

downwind nonattainment problem.

Under these circumstances, the upwind

area would be required to retain or

adopt SIP provisions that meet the

requirements of section 110(a)(2)(D).
60324 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

To assure that SIPs include required

controls, section 110(k)(5) authorizes

EPA to find that a SIP is substantially

inadequate to meet an CAA

requirement, and to require (‘‘call for’’)

the State to submit, within a specified

period, a SIP revision to correct the

inadequacy. This EPA requirement for a

SIP revision is known as a ‘‘SIP call.’’

Specifically, section 110(k)(5) provides,

in relevant part:

Whenever the Administrator finds that the

applicable implementation plan for any area

is substantially inadequate to attain or

maintain the relevant [NAAQS], to mitigate

adequately the interstate pollutant transport

described in section 176A or section 184, or

to otherwise comply with any requirement of

this Act, the Administrator shall require the

State to revise the plan as necessary to

correct such inadequacies. The Administrator

shall notify the State of the inadequacies, and

may establish reasonable deadlines (not to

exceed 18 months after the date of such

notice) for the submission of such plan

revisions.

By today’s action, EPA is proposing to

determine that the SIPs under the 1-

hour ozone NAAQS for the States

identified in today’s action are

substantially inadequate to comply with

the requirements of section 110(a)(2)(D)

and to mitigate adequately the regional,

interstate ozone transport described in

section 184, because ozone precursor

emissions and transported ozone from

those States contribute significantly to

nonattainment downwind. Based on

these findings, EPA today proposes a

SIP call to require the identified States

to reduce emissions to mitigate their

contribution.

If a State fails to submit the required

SIP provisions in response to this SIP

call, EPA is required to issue a finding

that the State failed to make a required

SIP submittal under section 179(a). This

finding has implications for sanctions as

well as EPA’s promulgation of a Federal

implementation plan (FIP). Sanctions

and a FIP are discussed in section V.,

SIP Revisions and Approvability

Criteria.

Under the 8-hour ozone NAAQS,

areas have not yet been designated as

attainment, nonattainment, or

unclassifiable, and are not yet required

to have SIPs in place. When those SIPs

become due, they must meet the

applicable requirements of section 110,

which apply to all areas, and SIPs for

areas designated nonattainment must

also meet the additional requirements in

subpart 1 of part D applicable to

nonattainment areas.

Section 110(a)(1) provides, in relevant

part—

Each State shall * * * adopt and

submit to the Administrator, within 3

years (or such shorter period as the

Administrator may prescribe) after the

promulgation of a national primary

ambient air quality standard (or any

revision thereof) * * * a plan which

provides for implementation,

maintenance, and enforcement of such

primary standard in each (area) within

such State.

Section 110(a)(2) provides, in relevant

part—

Each implementation plan submitted by a

State under this CAA shall be adopted by the

State after reasonable notice and public

hearing. Each such plan shall (meet certain

requirements, including those found in

section 110(a)(2)(D)).

These two provisions, read together,

require SIP revisions under the revised

NAAQS within 3 years of the date of the

revision, or earlier if EPA so requires,

and require that those SIP revisions

meet the requirements of section

110(a)(2), including subparagraph (D). It

should be noted that the schedule for

these section 110(a)(2) SIP submissions

for all ozone areas differs from the

schedule for the SIP submissions

required under section 172(b) for part D

SIP submissions for ozone

nonattainment areas. These part D SIP

submissions are required for all areas

that are designated nonattainment under

the 8-hour NAAQS and must be

submitted within 3 years of the date of

designation. The submission of SIP

revisions containing the regional NOX

reductions proposed under this

rulemaking earlier than the part D

nonattainment submissions will assist

the downwind nonattainment areas in

their attainment planning.

The EPA believes it has the authority

to establish different submittal

schedules for different parts of the

section 110(a)(1) SIP revision.

Specifically, EPA proposes to require

first the portion of the section 110(a)(1)

SIP revision that contains the controls

required under section 110(a)(2)(D). The

EPA proposes to require the section

110(a)(2)(D) submittal first for the

purpose of securing upwind reductions

at an earlier stage in the regional SIP

planning process. This information on

controls in upwind States is essential to

the downwind States in the latter States’

attainment planning.

In summary, EPA is proposing to

determine, under section 110(k), that

the 1-hour ozone NAAQS SIPs for

certain States are deficient because the

SIPs do not impose sufficient controls

on their sources to meet the

requirements of section 110(a)(2)(D),

and EPA is proposing to require those

States to submit SIP revisions

containing adequate controls. The EPA

is proposing to require, under section

110(a)(1), that certain States must

submit SIP revisions under the 8-hour

ozone NAAQS to meet the requirements

of section 110(a)(2)(D). For simplicity,

today’s rulemaking occasionally uses

the term ‘‘SIP call’’ to describe both EPA

actions.

2. Overview of Elements of Section

110(a)(2)(D)

a. Summary of Section 110(a)(2)(D).

As noted above, section 110(a)(2)(D) is

the operative provision for determining

whether additional controls are required

to mitigate the impact of upwind

sources on downwind air quality, with

respect to both the 1-hour and 8-hour

ozone NAAQS. Separate determinations

must be made for each NAAQS.

Section 110(a)(2)(D) provides, in

relevant part, that each SIP must:

* * * contain adequate provisions * * *

prohibiting, consistent with the provisions of

this title, any source or other type of

emissions activity within the State from

emitting any air pollutant in amounts which

will * * * contribute significantly to

nonattainment in, or interfere with

maintenance by, any other State with respect

to any such national primary or secondary

ambient air quality standard * * *.

According to section 110(a)(2)(D), the

SIP for each area, regardless of its

designation as nonattainment or

attainment (including unclassifiable),

must prohibit sources within the area

from emitting emissions that:

‘‘contribute significantly’’ to

‘‘nonattainment’’ in a downwind State,

or that ‘‘interfere with maintenance’’ in

a downwind State.

b. Significant Contribution to

Nonattainment. The initial prong under

section 110(a)(2)(D) is whether sources

‘‘contribute significantly’’ to

‘‘nonattainment in * * * any other

State’’ with respect to the NAAQS. The

initial inquiry for this prong is to

identify and determine the geographic

scope of ‘‘nonattainment’’ downwind.

The EPA proposes to interpret this term

to refer to air quality and not to be

limited to currently-designated

nonattainment areas. Section

110(a)(2)(D) does not refer to

‘‘nonattainment areas,’’ which is a

phrase that EPA interprets to refer to

areas that are designated nonattainment

under section 107 (section

107(d)(1)(A)(I)). Rather, the provision

includes only the term ‘‘nonattainment’’

and does not define that term. Under

these circumstances, EPA has discretion

to give the term a reasonable definition,

and EPA proposes to define it to include

areas whose air quality currently

violates the NAAQS, and will likely

continue for some time to violate,
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60325

regardless of the designation of those

areas (compare section 181(b)(2)(A)

(referring to ozone ‘‘nonattainment

area’’ which EPA interprets as an area

designated nonattainment) and section

211(k)(10)(D)).

For present purposes, EPA is

examining the air quality for the 1993–

1995 years, but EPA expects to refer to

1996 (and perhaps 1997) data as the

rulemaking proceeds.

As discussed below, to determine

whether emissions from sources in an

upwind area significantly contribute to

nonattainment downwind, EPA

proposes to compare NOX emissions

reductions upwind with ozone

reductions downwind. For this purpose,

EPA assumes that areas with current air

quality indicating nonattainment for the

1-hour standard will be required to

implement certain controls under the

CAA, through the year 2007, which is

the attainment date for ozone

nonattainment areas classified as severe17. Accordingly, EPA proposes to

determine, through air quality

modeling, which areas with current air

quality indicating nonattainment for

both the 1-hour and 8-hour standards

will continue to be in nonattainment in

the year 2007, even after

implementation of controls specifically

required under the CAA. Because this

projection is occurring through the year

2007, it is also necessary to take into

account growth in emissions, generally

due to economic growth and greater use

of vehicles, to that time. If an area with

air quality currently indicating

nonattainment is modeled to continue

to be in nonattainment as of the year

2007, then emissions from sources in

upwind areas may be considered to

‘‘contribute significantly’’ to the current

nonattainment problem, depending on

the factors described below. On the

other hand, if an area the current air

quality of which measures

nonattainment is modeled to be in

attainment in the year 2007 due to

imposition of required CAA controls,

then EPA proposes not to consider

emissions from sources in upwind areas

to ‘‘contribute significantly’’ to that

downwind area.

The EPA’s decision is explained

below for choosing the year 2007 as the

date for assuming the implementation of

controls and for modeling air quality.

The EPA proposes a similar analysis

for purposes of the 8-hour NAAQS. The

EPA will consider as ‘‘nonattainment’’

any area that has monitored

nonattainment air quality currently, and

for which modeling shows is likely to

continue to be in nonattainment in the

year 2007 after application of controls

specifically required under the CAA.

After determining the scope of the

downwind nonattainment problem, EPA

must next analyze whether the

emissions from sources in the upwind

area ‘‘contribute significantly’’ to the

nonattainment problem. As described

below, EPA analyzed all NOX emissions

in specified upwind areas, made

proposed determinations as to

significant contributions based on the

entire inventory of the area’s NOX

emissions and is requiring SIP revisions

that address overall levels of NOX

emissions. By contrast, EPA is not, in

this rulemaking, determining whether

particular sectors of the NOX inventory

‘‘contribute significantly’’ and is not

mandating controls on particular sectors

of that inventory.

Neither the CAA nor its legislative

history provides meaningful guidance

for interpreting the term, ‘‘contribute

significantly’’ (H.Rept. 101–491, 101st

Cong., 2d sess., 1990, 218). The simpler

part of the analysis concerns the term,

‘‘contribute.’’ In EPA’s view, if

emissions have an impact on downwind

nonattainment, those emissions should

be considered to contribute to the

nonattainment problem. Generally,

because ozone is a secondary pollutant

formed as a result of complex chemical

reactions, it is not possible to determine

downwind impact on a source-bysource basis. However, if air quality

modeling shows that the aggregation of

emissions from a particular geographic

region affect a nonattainment problem,

then all of the emissions in that region

should be considered as contributors to

that nonattainment problem.

Whether a contribution from sources

in a particular upwind area is

‘‘significant’’ depends on the overall air

quality context. The EPA is proposing a

‘‘weight of evidence’’ test under which

several factors are considered together,

but none of them individually

constitutes a bright-line determination.

The EPA is proposing and soliciting

comment on two alternative

interpretations of section 110(a)(2)(D).

Each of the two interpretations relies on

a set of factors to make the

determinations required under section

110(a)(2)(D). In addition, each of the two

relies on the same factors. However,

each relies on different factors in

different parts of the analysis.

Under the first interpretation of

section 110(a)(2)(D), the weight of

evidence test for determining significant

contribution focuses on factors

concerning amounts of emissions and

their ambient impact, including the

nature of how the pollutant is formed,

the level of emissions and emissions

density (defined as amount of emissions

per square mile) in the particular

upwind area, the level of emissions in

other upwind areas, the amount of

contribution to ozone in the downwind

area from upwind areas, and the

distance between the upwind sources

and the downwind nonattainment

problem. Under this approach, when

emissions and ambient impact reach a

certain level, as assessed by reference to

the factors identified above, those

emissions would be considered to

‘‘contribute significantly’’ to

nonattainment. The EPA would then

determine what emissions reductions

must be required in order to adequately

mitigate these contributions. Evaluation

of the costs of available measures for

reducing upwind emissions enters into

this determination, as well as to the

extent known (at least qualitatively), the

relative costs of, amounts of emission

reductions from, and ambient impact of,

measures available in the downwind

areas. The EPA proposes to require

upwind areas to implement a NOX

budget reflecting cost-effective controls

that compare favorably, at least

qualitatively, with the costs of controls

downwind and that reduces ozone

levels downwind.

Under the second interpretation of

section 110(a)(2)(D), the weight of

evidence test for determining significant

contribution includes all of the factors

identified immediately above, including

the factors that comprise the adequate

mitigation test. That is, the relevant

factors concern upwind emissions and

ambient impact therefrom, as well as the

costs of the available measures for

reducing upwind emissions and, to the

extent known (at least qualitatively), the

relative costs of, amounts of emissions

reductions from, and ambient impact of

measures available in the downwind

areas. Thus, under this second

interpretation, the cost effectiveness of

controlling upwind emissions would be

an important, but not necessarily a

controlling factor in evaluating whether

emissions meet the significant

contribution test. As a result, EPA may

conclude that a certain amount of the

upwind emissions contributes

significantly to downwind problems

because, among other things, that

amount may be eliminated through

controls that are relatively more cost

effective. However, EPA would not

conclude that the remaining emissions

contribute significantly because the

additional available controls that might

be implemented are not as cost effective.

Under this second interpretation, once

EPA determines what amount of

emissions contribute significantly to

problems downwind, the remedy would

be for EPA to require the elimination of
60326 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

that amount of upwind emissions and to

determine the NOX budgets accordingly.

Under either the first or second

interpretation of section 110(a)(2)(D),

EPA would be considering the relative

costs and cost effectiveness of various

controls in deciding how much each

State would need to reduce its

emissions. The methodology EPA would

employ to reach this result under either

interpretation is set forth more fully in

sections II and III of today’s action.

As discussed above, unhealthful

levels of ozone result from emissions of

NOX and VOC from thousands of

stationary sources and millions of

mobile sources across a broad

geographic area. Each source’s

contribution is a small percentage of the

overall problem; indeed, it is rare for

emissions from even the largest single

sources to exceed 1 percent of the

inventory of ozone precursors for a

single metropolitan area. Under these

circumstances, even complete

elimination of any given source’s

emissions may well have no measurable

impact in ameliorating the

nonattainment problem. Rather,

attainment requires controls on

numerous sources across a broad area.

Ozone is a regional scale problem that

requires regional scale reductions.

The National Academy of Sciences

(NAS) study, ‘‘Rethinking the Ozone

Problem in Urban and Regional Air

Pollution’’ (2) emphasized this aspect of

ozone formation. According to this

report, high concentrations of ozone

occur concurrently in the Eastern

United States in urban, suburban and

rural areas on scales of over 1000

kilometers. The NAS report describes a

‘‘persistent blanket of high ozone in the

Eastern United States’’ that can last for

several days. Since rural ozone values

commonly exceed 90 parts per billion

(ppb) on these occasions, an urban area

needs an ozone increment of only 30

ppb to cause an exceedance of the 1-

hour ozone standard in a downwind

area. Clearly, attainment strategies must

include controls on numerous sources

across broad areas.

In light of this ‘‘collective

contribution’’ characteristic of ozone

formation and control, EPA proposes

that if contributions from an upwind

area’s emissions, taken together, are

considered to be an important portion of

the downwind area’s nonattainment

problem, then this factor tends to

indicate that the upwind emissions as a

whole, as well as each of the upwind

emitters, make a ‘‘significant’’

contribution. The fact that emissions

from any particular source, or even a

group of sources, may in-and-ofthemselves be small, does not mean

those sources’ emissions are not

‘‘significant’’ within the meaning of

section 110(a)(2)(D). Those sources’

emissions are generally ‘‘significant’’ if,

when they are combined with emissions

from other sources in the same upwind

area, they total upwind emissions that

are ‘‘significant.’’ Even so, it should be

noted that the collective contribution

factor is only one of various factors that

EPA proposes to consider in

determining whether emissions from an

area constitute a ‘‘significant’’

contribution to a downwind problem.

The amounts of emissions from the area

and, in certain cases, emissions density,

remain important factors. Depending on

all the facts and circumstances, these

other factors may tend to indicate that

emissions from a particular area should

not be considered to contribute

significantly, notwithstanding the fact

that those emissions may be linked in

some manner with emissions from other

upwind areas that are considered to be

significant contributors.

In several rulemakings promulgated

and court decisions handed down, in

the 1980’s, EPA interpreted and applied

the predecessors to sections 110(a)(2)(D)

and 126 (e.g., State of New York v. EPA,

852 F.2d 574 (D.C. Cir. 1988); Air

Pollution Control District of Jefferson

County, Kentucky v. EPA, 739 F.2d 1071

(6th Cir. 1984); Connecticut v. EPA, 696

F.2d 147 (2d Cir. 1982)). Although these

rulemakings and court decisions

generally employed multifactor

formulas for the ‘‘significant

contribution’’ test that bear some

similarity to the formula EPA is

proposing today, they have limited

relevance to the issues in the present

rulemaking because of the numerous

differences in the relevant factors. For

example, in the earlier rulemakings

compared to the present rulemaking, the

pollutants and precursors are different,

and the inventories of emissions and

number of emitters in the upwind and

downwind areas are different. The

significant contribution test is a factsand-circumstances analysis that

depends on these factors, and

differences among these factors may

yield different results under this test.

Accordingly, the differences in the key

factors between the earlier decisions

and today’s proposal means that those

earlier decisions are not determinative

for today’s proposed action.

For purposes of today’s rulemaking,

EPA determined the amount of

contribution to downwind air quality,

under both the 1-hour NAAQS and the

8-hour NAAQS, by employing an air

quality model that assumed a zero level

of anthropogenic emissions from the

various upwind areas. The results of

those model runs, as well as their other

assumptions and characteristics, are

described in detail below.

As described below, EPA made

separate determinations as to which

upwind areas ‘‘contribute significantly’’

to nonattainment under the 1-hour

NAAQS and under the 8-hour NAAQS.

Those separate determinations resulted

in identifying the same States for both

the 1-hour and the 8-hour NAAQS.

c. Interfere with Maintenance. Section

110(a)(2)(D) also prohibits emissions

that ‘‘interfere with maintenance’’ of the

NAAQS in a downwind State. An area

is obligated to maintain the NAAQS

after the area has reached attainment.

This requirement of section 110(a)(2)(D)

does not, by its terms, incorporate the

qualifier of ‘‘significantly.’’ Even so,

EPA believes that for present purposes,

the term ‘‘interfere’’ should be

interpreted much the same as the term

‘‘contribute significantly,’’ that is,

through the same weight of evidence

approach.

With respect to the 1-hour NAAQS,

the ‘‘interfere-with-maintenance’’ prong

appears to be inapplicable. The EPA has

determined that the 1-hour NAAQS will

no longer apply to an area after EPA has

determined that the area has attained

that NAAQS. Under these

circumstances, emissions from an

upwind area cannot interfere with

maintenance of the 1-hour NAAQS.

With respect to the 8-hour NAAQS,

the ‘‘interfere-with-maintenance’’ prong

remains important. After an area has

reached attainment of the 8-hour

NAAQS, that area is obligated to

maintain that NAAQS (sections

110(a)(1) and 175A). Emissions from

sources in an upwind area may interfere

with that maintenance.

The EPA proposes to apply much the

same approach in analyzing the first

component of the ‘‘interfere-withmaintenance’’ issue, which is

identifying the downwind areas whose

maintenance of the NAAQS may suffer

interference due to upwind emissions.

The EPA has analyzed the ‘‘interferewith-maintenance’’ issue for the 8-hour

NAAQS by examining areas whose

current air quality is monitored as

attaining the 8-hour NAAQS, but for

which air quality modeling shows

nonattainment in the year 2007. This

result is projected to occur,

notwithstanding the imposition of

certain controls required under the

CAA, because of projected increases in

emissions due to growth in emissions

generating activity. Under these

circumstances, emissions from upwind

areas may interfere with the downwind

area’s ability to maintain the 8-hour

NAAQS. Ascertaining the impact on the
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60327

downwind area’s air quality of the

upwind area’s emissions aids in

determining whether the upwind

emissions interfere with maintenance.

d. Remedying the Significant

Contribution. After identifying States

whose sources do ‘‘contribute

significantly’’ to a nonattainment

problem or interfere with maintenance

downwind, it is necessary to determine

the appropriate limit on emissions

required in each upwind SIP. The EPA

is proposing, in the alternative, two

different analyses for the remedies

which are tied to the two alternatives for

the ‘‘weight of evidence’’ test.

i. Adequate Mitigation. Under the first

interpretation of section 110(a)(2)(D),

EPA does not consider costs in

determining whether upwind emissions

contribute significantly to

nonattainment or interfere with

maintenance. Instead, once EPA

determines, on the basis of factors

generally related to emissions, that

those emissions do contribute

significantly to nonattainment (or

interfere with maintenance), EPA then

determines what emissions reductions

must be required in order to adequately

mitigate these contributions. Evaluation

of relative costs enters into this

determination.

Adequate mitigation would amount to

eliminating a sufficient portion of the

upwind emissions so that they no longer

contribute significantly to

nonattainment or interfere with

maintenance.

In the present case, EPA proposes to

determine an allowable level of NOX

emissions for each of the 23

jurisdictions with sources that trigger

the requirements of section 110(a)(2)(D).

Given the need to reduce this overall

regional level of ozone, as discussed

earlier, EPA determined this ‘‘budget’’

of emissions by, in the first instance,

calculating the emissions achievable by

applying the most reasonable, costeffective controls on NOX emissions in

the 23 jurisdictions. The control

measures considered and those

determined to be the most reasonable

and cost-effective are detailed below. In

selecting those control measures

determined to be the most reasonable

and cost-effective, EPA carefully

considered the recommendations made

by OTAG on July 8, 1997. (The OTAG

process is described in section I.F. of

this rulemaking.) The budget

calculations described below generally

fall within the range of OTAG’s

recommendations.

The statewide emissions budgets

proposed in this rulemaking were not

modeled directly to determine their air

quality benefits. The EPA believes,

however, that the air quality impact of

implementing these reductions would

be very similar to results previously

modeled by OTAG. This modeling is

identified in section IX, Air Quality

Analyses. The downwind air quality

benefits from these reductions are

sufficient for EPA to conclude that they

would adequately mitigate the

contribution from the upwind sources.

ii. Elimination of Contribution. Under

the second interpretation of section

110(a)(2)(D), costs are considered as part

of the calculation as to what (if any)

amount of emissions contribute

significantly to nonattainment or

interfere with maintenance. The EPA

proposes to determine those amounts

for each State by considering the factors

described above and the extent to which

the State’s emissions can be reduced

through the most cost-effective controls

that reduce ozone levels downwind.

Once EPA makes this determination,

EPA would conclude that requiring

those cost-effective controls is mandated

under the provisions of section

110(a)(2)(D) that require SIP provisions

‘‘prohibiting’’ that amount of emissions.

Thus, under this alternative

interpretation, a SIP meets the

requirement for ‘‘prohibiting’’ emissions

that contribute significantly to

nonattainment, or interfere with

maintenance, downwind, by

implementing cost-effective controls

determined to improve air quality

downwind.

iii. Comparison of the Two Legal

Interpretations of Section 110(a)(2)(D).

The EPA solicits comments on which of

the two legal interpretations of section

110(a)(2)(D), as described above, should

be used. Each interpretation relies on

the same factors (although certain

factors enter into different parts of the

analysis under the two interpretations).

Because each relies on the same factors,

there is little technical difference

between the two interpretations. Each

requires the same determinations as to,

for example, the ambient impact of

upwind emissions and the cost

effectiveness of controls.

Moreover, as proposed in today’s

action, each interpretation leads to the

same conclusion as to which States are

considered to have emissions that

significantly contribute to downwind

problems, and as to the amounts of NOX

budgets that those States should meet.

However, the two interpretations have

different legal justifications. As noted

above, section 110(a)(2)(D) provides that

the SIP for the upwind area must

‘‘contain adequate provisions * * *

prohibiting * * * [sources] from

emitting any air pollutant in amounts

which will * * * contribute

significantly to nonattainment in, or

interfere with maintenance by, any

other State * * *’’ Under the first

interpretation, EPA may determine that

a relatively larger inventory of

emissions contributes significantly to

nonattainment (or interferes with

maintenance) in light of the fact that the

costs of controlling those emissions are

not considered in determining

significant contribution. The EPA would

then require adequate mitigation of the

full set of emissions that contribute to

nonattainment or interfere with

maintenance.

Other relevant provisions indicate

that the CAA could be construed to

require mitigation, and not necessarily

complete elimination, of emissions that

contribute to air quality problems

downwind. Section 110(k)(5) authorizes

the Administrator to promulgate a SIP

call whenever she finds that a SIP is

‘‘substantially inadequate to attain or

maintain the relevant [NAAQS], to

mitigate adequately the interstate

pollutant transport described in section

176A or 184, or to otherwise comply

with any requirement of this Act’’

(emphasis added). Section 176A

describes interstate transport of air

pollutants generally, and section 184

describes ozone transport in the

northeast region in particular, which

constitutes part of the transport

phenomenon at issue in today’s

proposal. Section 176A authorizes the

creation of a transport region when

emissions from one or more States

contribute significantly to a NAAQS

violation in another State and further

authorizes a transport commission to,

among other things, assess strategies for

mitigating the interstate pollution.

These provisions, read together, indicate

that adequate mitigation of transport is

an appropriate response to a SIP call.

Arguably, this interpretation should

hold when EPA issues a SIP call based

on section 110(a)(2)(D), and when EPA

mandates a SIP revision under section

110(a)(1), based on section 110(a)(2)(D).

The second interpretation focuses on

the provisions of section 110(a)(2)(D)

that the SIP must include provisions to

‘‘prohibit’’ any emitting activity from

emitting in ‘‘amounts’’ that contribute

significantly to downwind

nonattainment or interfere with

maintenance. The EPA has determined

the States whose full set of NOX

emissions contribute markedly to

downwind problems. The term

‘‘prohibit’’ could be interpreted to

require EPA, upon finding that a State’s

full set of emissions ‘‘contribute

significantly’’ to nonattainment, must

then require the SIP to eliminate that

full set of emissions. This construction
60328 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

could mean that EPA must require the

State to shut down all of the emissiongenerating activities. It is doubtful

Congress would have intended this

result.

The EPA’s second interpretation

avoids this possible result by taking into

account the relative cost effectiveness of

the upwind and downwind controls in

defining the ‘‘amounts’’ of emissions in

each State that contribute significantly

to the downwind problem. Once EPA

has set those ‘‘amounts’’ in light of its

consideration of the cost factors, the

SIPs for the affected States would then

need to prohibit only those amounts.

iv. Other Issues. States will have the

flexibility to choose their own mix of

control measures to meet the proposed

statewide emissions budgets. That is,

States are not constrained to adopt

measures that mirror the measures EPA

used in calculating the budgets. In fact,

EPA believes that many control

measures not on the list relied upon to

develop EPA’s proposed budgets are

reasonable—especially those like

enhanced vehicle inspection and

maintenance programs that yield both

NOX and VOC emissions reductions.

Thus, one State may choose to primarily

achieve emissions reductions from

stationary sources while another State

may focus emission reductions from the

mobile source sector. Furthermore,

States may choose to pursue costeffective energy efficiency opportunities

as a means to reduce the control

measures necessary to meet their

statewide emission budgets.

e. Control Implementation and Budget

Attainment Dates. The EPA proposes to

require that the SIP revisions impose an

implementation date for the required

controls of 3 years from the date of the

required SIP submission, which would

result in compliance by those sources by

no later than September 2002. However,

the EPA is soliciting comments on the

range of implementation dates from

between September 2002 and September

2004. The EPA seeks comment on

which date within this 2-year range is

appropriate, in light of the feasibility of

implementing controls and the need to

provide air quality benefits as

expeditiously as practicable. The EPA is

proposing an implementation date of

September 2002 in order to allow

coordination of this rulemaking with its

response to 8 section 126 petitions

which are discussed below in section

I.E, Section 126 Petitions. Although the

EPA’s actual proposed compliance date

is September 2002, because the Agency

is seeking comment on a range from

September 2002 to September 2004, the

Agency refers to the range of

implementation dates throughout this

rulemaking. The EPA further proposes

that States be required to meet the

mandated budgets by the end of the year

2007, by which time additional

reductions from various Federal

measures will also be achieved.

The EPA believes that requiring

implementation of the upwind controls,

and thereby mandating upwind

reductions, by no later than these 2002–

4 dates, is consistent with the

attainment schedule for the downwind

areas. Because the downwind areas

depend on upwind reductions to reach

attainment, mandating upwind controls

on a schedule consistent with

downwind attainment requirements is

appropriate.

A review of the attainment schedule

under the 1-hour NAAQS would be

useful. Under the attainment schedule,

serious areas are required to attain by

the end of 1999, severe-15 areas are

required to attain by the end of 2005,

and severe-17 areas are required to

attain by the end of 2007 (section

181(a)(1)). If a serious area fails to meet

its 1999 attainment date, it is to be

reclassified (‘‘bumped up’’) to severe-15

(section 181(b)(2)). However, an area

may fail to reach attainment by its

attainment date, but avoid bump up, if

EPA grants a 1-year extension. An area

is eligible for a 1-year extension if,

among other things, it has no more than

one exceedance of the NAAQS in the

attainment-date year. The EPA may

grant another extension for the next year

under the same conditions (section

181(a)(5)). If an area receives two 1-year

extensions, it may reach attainment in

the following year (the second year after

the attainment-date year) if, again, it has

no more than one exceedance of the

NAAQS. Under these circumstances, the

area will have had no more than three

exceedances over a 3-year period (the

attainment-date year and the 2 next

years), which would qualify it for

attainment under the 1-hour NAAQS.

The EPA has indicated that once it

determines that an area has achieved air

quality that satisfies the 1-hour NAAQS,

the NAAQS will be rescinded with

respect to that area.

Although controls on upwind

emissions are designed to assist

downwind nonattainment areas in

reaching the NAAQS, EPA is aware that

at this point, it is not possible for EPA

to mandate controls on upwind areas

within the OTAG region in sufficient

time to help serious areas reach

attainment by their end-of-1999

attainment date. The amount of time

that is necessary to assure that the

rulemaking proposed today is well

considered by all affected parties, added

to the amount of time necessary for the

States to adopt the required SIP

revisions, and the amount of lead-time

necessary to implement the required

controls, means that those controls

cannot be expected to be in place in

time to assist the serious areas in

reaching their attainment date.

The next attainment date is 2005,

which applies to severe-15 areas, such

as the Baltimore area, and which would

apply to any serious area that is bumped

up. The EPA’s proposal to require

upwind controls to be implemented by

no later than September 2004—in time

for the beginning of the ozone season for

the affected States—is sensible in light

of this 2005 attainment date.

Implementing controls earlier than

September 2004, or at least phasing in

some controls, if not all of them, prior

to that date, would improve the chance

for minimizing exceedances during the

3-year period up to, and including,

2005, which will facilitate reaching

attainment as of this date. In particular,

to the extent that the State chooses

controls on major stationary sources of

NOx, EPA believes it would be feasible

to implement some of those controls

earlier than September 2004. However,

EPA is aware that implementation of

controls for other sources may be more

problematic. The EPA solicits comments

on what dates within the range of 3 to

5 years of the required SIP submission

would be appropriate for

implementation of the controls.

Full implementation by no later than

September 2004 would mean that all of

the upwind controls required under the

rulemaking proposed today would be in

place as of the November 15, 2005

attainment date for the downwind

severe-15 areas. Failure to implement

those controls prior to September 2004

may mean that the downwind area may

record too many exceedances in the 3-

year period prior to the end of 2005, so

that it would not be possible to reach

attainment as of that time. However,

implementation of these reductions by

September 2004, coupled with any

necessary additional reductions from

the downwind sources, may result in no

more than one exceedance in the

downwind area during the attainment

year and during each of the next 2 years

thereafter. Under these circumstances,

the downwind area would be eligible for

the 1-year extensions described above

and would reach attainment by the year

2007.

Similarly, full implementation by

September 2004 would mean that

severe-17 areas would receive the

benefit of reduced upwind emissions

during the 3-year period up to, and

including, their 2007 attainment year. In

the OTAG region, the severe-17 areas
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60329

3 Letter of January 29, 1997 from Jeffrey C. Smith,

Executive Director, Institute of Clean Air

Companies, to Docket No. A–95–28: Acid Rain

Program, Nitrogen Oxides Emission Reduction.

include the Philadelphia, New York,

Milwaukee, and Chicago areas. These

reductions should greatly assist the

downwind areas in reaching attainment

by the end of 2007.

An implementation date of between

September 2002 September 2004 is also

consistent with the attainment date

scheme for the 8-hour NAAQS. The EPA

intends to promulgate designations for

areas under the 8-hour NAAQS by the

year 2000. The CAA provides for

attainment dates of up to 5 years or 10

years after designation. Therefore, the

first attainment date for many areas

under the 8-hour standard could be

2005. Section 172(a)(2)(C) has a two, 1-

year extension scheme applicable for

areas under the 8-hour NAAQS that is

similar to that described above, under

section 181(a)(5), applicable to areas

under the 1-hour NAAQS. Accordingly,

full implementation of mandated SIP

controls in the upwind areas by no later

than September 2004 may allow

downwind areas to reach attainment of

the 8-hour NAAQS by 2007, counting

the two 1-year extensions in the same

manner as for severe-15 areas under the

1-hour NAAQS. In addition, the EPA

believes that compliance no later than

September 2004 by the utility and

nonutility sector, with the emission

limits assumed in setting the emission

budgets or application of controls to

other source categories, is feasible.

Further, EPA notes that the September

27, 1994 OTC NOX Memorandum of

Understanding (MOU) provides that

large utility and nonutility NOx sources

should comply with the Phase III

controls by the year 2003. The levels of

control in the MOU are 75 percent or

0.15 lb/106 btu in the inner and outer

zones, levels comparable to the controls

assumed in setting the budget for this

rulemaking. In addition, in comments to

EPA’s proposed Phase II NOx reduction

program under the Acid Rain provisions

of the CAA 3, the Institute of Clean Air

Companies (ICAC) stated that more than

sufficient vendor capacity existed to

supply retrofit of selective catalytic

control to the boilers affected by the

proposed rule. The ICAC in fact

indicated that additional catalyst

capacity could be added if needed.

Although EPA is proposing today that

SIPs mandate implementation of the

required SIP controls by a date within

a range of September 2002 and

September 2004, EPA is also proposing

that the affected States demonstrate

achievement of their NOX budgets as of

the end of the year 2007. In addition,

EPA used the 2007 date to analyze for

modeling purposes the impact of

upwind emissions on nonattainment air

quality. Using the 2007 date means that

the States will be able to account for the

additional reductions from Federal

measures occurring between the date

that SIP controls are implemented and

the end of 2007, although the State must

also account for growth in emissions

during this time. Using the 2007 date is

sensible in part because OTAG used this

date for these purposes and compiled

substantial technical information—such

as information concerning inventories—

based on this date. It is, therefore,

efficient for EPA to use this same

information. Developing comparable

information for an earlier date would be

time consuming and resource intensive.

In addition, it is uncertain that there

would be significant differences in

amounts of emissions and impact on

ambient air quality between an earlier

date and 2007, in light of the fact that

during this period, emissions would

generally increase somewhat as a result

of growth in activities that generate

emissions, but would also decrease due

to continued application of federally

mandated controls. Accordingly,

requiring accounting for a budget as of

the 2007 date is both practicably

indicated and is a reasonable surrogate

for requiring this accounting as of

September 2004.

E. Section 126 Petitions

The EPA has received section 126

petitions from eight States: Connecticut,

Maine, Massachusetts, New Hampshire,

New York, Pennsylvania, Rhode Island

and Vermont. The petitions vary as to

the type and geographic location of

sources they identify as meriting a

finding of significant contribution. The

petitions also vary as to the levels of

controls they recommend. In addition,

EPA has received a petition from the

State of Wisconsin asking EPA to

promulgate a SIP call under section

110(k)(5) requiring the States of Illinois,

Indiana, Iowa, Kentucky and Missouri

to submit SIP revisions addressing the

purported impact of their emissions on

Wisconsin. By letter dated August 8,

1997, from Mary D. Nichols, Assistant

Administrator for Air and Radiation, to

Michael J. Walls, Chief, Environmental

Protection Bureau, Office of the

Attorney General, State of New

Hampshire, EPA provided technical

guidance concerning section 126

petitions. The EPA is now studying the

petitions and will prepare a notice(s) of

proposed rulemaking to grant or deny

them.

The EPA’s response to a section 126

petition differs from today’s action in

several ways. Today’s action is a

proposed SIP call under section

110(k)(5) for SIP provisions meeting the

requirements of section 110(a)(2)(D) for

the 1-hour ozone NAAQS, coupled with

a proposed requirement under section

110(a)(1) for submission of SIP

provisions meeting the requirements of

section 110(a)(2)(D) for the 8-hour ozone

NAAQS. The EPA bases this action on

a technical analysis as to whether the

entire NOX emissions inventory of an

individual upwind State contributes

significantly to an ozone nonattainment

problem downwind. If EPA concludes

that the NOX emissions from that State

make such a significant contribution,

EPA will require the State to submit SIP

provisions that limit the State’s NOX

emissions to the level mandated by

EPA, but through any combination of

measures affecting any sector of the

inventory chosen by the State. If the

State does not make the required

submission, EPA may, among other

things, promulgate a FIP in accordance

with section 110(c).

By comparison, a section 126 petition,

by the terms of section 126(b)–(c), is

limited to upwind major stationary

sources and not other sectors of the

upwind emissions inventory. Moreover,

a section 126 petition may seek a

finding concerning upwind sources in

more than one State. Further, if EPA

grants the petition, it is EPA, and not

the States, that promulgates direct

controls for the major sources.

The EPA’s response to section 126

petitions would bear relevance to

today’s action. The section 126 petitions

and section 110(k)(5)/110(a)(1) action

both require technical analysis of

whether upwind sources contribute

significantly to a downwind

nonattainment or maintenance problem.

However, EPA’s section 110(k)(5)/

110(a)(1) action results in a mandate for

the States to submit SIP revisions that

conform to only minimum guidance

provided by EPA. On the other hand,

the section 126 petitions, if granted,

would result in EPA selection and

imposition of controls directly on major

stationary sources. These controls could

provide a template for the SIP

provisions the States must include in

their rulemaking response to EPA’s

section 110(k)(5)/110(a)(1) rulemaking

or, if necessary, a FIP.

EPA believes that both the 110

process as outlined and 126 petition

processes are aimed at addressing

regional transport of ozone forming

pollutants and can be fully coordinated.

The 110 process outlined provides the

potential to deal comprehensively with
60330 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

4Under the two alternative interpretations of

section 110(a)(2)(D) that EPA is proposing today, if

upwind emissions meet the factors related to

emissions and contribution to ambient air quality,

EPA would conclude either that the emissions

significantly contribute to a nonattainment

problem, or the emissions may significantly

contribute, depending on further analysis of other

factors, including costs.

transported pollutants that contribute

significantly to downwind

nonattainment, and importantly, allows

individual States to make choices about

cost-effective source controls best fitting

their unique State situations. The 126

petition process provides assurance to

petitioning States that upwind sources

of air pollution will be addressed in a

timely manner. Thus, each of these

processes may provide important and

complementary tools to address the

regional ozone transport problem.

Over the next several months, EPA

will be working with the affected States

to ensure these two processes are fully

coordinated. This will provide

maximum certainty for State and

business planning requirements. The

EPA’s goal in this effort will be to

ensure that States achieve the air quality

reductions EPA determines through

rulemaking are necessary to address

regional transport while providing the

maximum flexibility to those States in

identifying the appropriate means to

meet those goals.

F. OTAG Process

The OTAG has completed the most

comprehensive analysis of ozone

transport ever conducted. The process

has resulted in more technical

information being gathered and more

modeling and monitoring analyses on

regional ozone transport than ever

before. The OTAG process was

fundamentally different from previous

efforts undertaken by the Federal

Government and the States to assess and

solve air pollution problems. What was

unique about the multistate,

multistakeholder OTAG process is that

for the first time, the Federal

Government has looked to the States

involved to provide the necessary

technical information and to aid in

determining an outcome which has

local, regional and national

implications.

The OTAG was organized into a

number of subgroups and work groups

that included members from the States,

EPA, industry and environmental

groups. The OTAG’s Policy Group,

comprised of the State Environmental

Commissioners, provided overall

direction to its subgroups for the

assessment of ozone formation and

transport, as well as the development of

control strategies that will reduce

concentrations of ozone and its

precursors. The subgroups within

OTAG addressed issues relating to

emissions inventories, monitoring,

modeling, and evaluated the

availability, effectiveness, and costs of

potential national, regional and local air

pollution control strategies. Specific

issues such as trading and market-based

incentives were also addressed.

The OTAG’s initial meetings were on

May 18, 1995, in Reston, VA, and June

19, 1995, in Washington, DC. The OTAG

continued to meet regularly for 2 years

until their final meeting in Washington,

DC on June 19, 1997. The goal of OTAG

was to:

* * * identify and recommend a strategy to

reduce transported ozone and its precursors

which, in combination with other measures,

will enable attainment and maintenance of

the national ambient ozone standard in the

OTAG region. A number of criteria will be

used to select the strategy including, but not

limited to, cost effectiveness, feasibility, and

impacts on ozone levels. (1)

To meet its goal, OTAG used

technical information from air quality

analyses and photochemical modeling.

The OTAG modeled three rounds of

emission reduction scenarios and

strategies, including varying control

measures geographically. The first

round of modeling was performed

during September and October 1996 and

provided an initial evaluation of

possible OTAG emission reduction

scenarios. The second round was

performed during November and

December 1996 and refined the

emission reduction level for the

strategies. The third round was

performed during January through

March 1997 and evaluated the

geographic applicability of the OTAG

strategies. These geographic modeling

runs provided information on applying

different levels of controls on utilities

and nonutility point sources at

incremental steps. Round-3 also

included a limited number of additional

modeling runs needed to address

comments made by a number of States

related to the geographical boundaries

of the zones defined for round-3

modeling. The OTAG modeling results

are discussed in section II, Weight of

Evidence Determination of Significant

Contribution, and are also available on

the OTAG webpage. This modeling,

along with other OTAG-generated

information, provided the technical

information necessary to make

recommendations to the Policy Group

and to EPA on what is needed to meet

the OTAG goal. The EPA received

OTAG’s final recommendations on July

8, 1997. These recommendations are

included in Appendix B.

II. Weight of Evidence Determination of

Significant Contribution

A. Introduction

This section documents the technical

information and analyses for the factors

concerning emissions and contributions

to ambient air quality that EPA uses to

determine which States in the OTAG

domain make a significant contribution

to nonattainment in downwind States.4

To a large extent, this assessment is

based upon the results of OTAG

modeling and air quality analyses as

well as information from other nonOTAG modeling studies. The OTAG

modeling available for this analysis

includes a set of initial emissions

sensitivity runs, the regional strategy

runs in rounds 1, 2, and 3, and the

geographic sensitivity runs performed to

support the design of strategies in

round-3.

B. Background Technical Information

The importance of interstate transport

to the regional ozone problem and

contributions from upwind States to

downwind States is supported by

numerous studies of air quality

measurements and modeling analyses.

In general, ozone episodes can occur on

many spatial and temporal scales

ranging from localized subregional

events lasting a day or 2, up to

regionwide episodes lasting as long as

10–14 days. The frequency of localized

versus regional episodes depends on the

characteristics of the large-scale

meteorological patterns which control

the weather in a particular summer

season. Local controls alone are not

sufficient to reduce ozone during

regionwide episodes since a substantial

amount of ozone may be transported

into the area from upwind sources. The

National Research Council report,

‘‘Rethinking the Ozone Problem in

Urban and Regional Air Pollution’’, (2)

cites numerous studies of widespread

ozone episodes during summertime

meteorological conditions in the East.

These episodes typically occur when a

large, slow-moving, high pressure

system envelopes all, or a large portion

of, the Eastern United States. The

relatively clear skies normally

associated with such weather systems

favor high temperatures and strong

sunlight, which enhances the formation

of high ozone concentrations. In

addition, the wind flow patterns can

lead to a build up of ozone

concentrations and the potential for

long-range ozone transport. Specifically,

winds are generally light in the center

of high pressure systems so that areas
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60331

under the center may have nearstagnation conditions resulting in the

formation of high ozone levels. As the

high pressure system moves eastward,

winds become stronger on the

‘‘backside’’ which increases the

potential for these high ozone levels to

be transported to more distant

downwind locations. Over several days,

the emissions from numerous small,

medium and large cities, major

stationary sources in rural areas, as well

as natural sources, combine to form a

‘‘background’’ of moderate ozone levels

ranging from 80 to 100 ppb (2) of which

30 to 40 ppb may be due to natural

sources. Concentration levels in the

range of 80 to 100 ppb and higher have

also been measured by aircraft aloft,

upwind of the Lake Michigan area (3),

as well as the Northeast Corridor (4).

Because this level of background ozone

is so close to the NAAQS, even a small

amount of locally-generated ozone will

result in an exceedance.

The importance of the episodic

meteorological conditions is heightened

by the spatial distribution of emissions

across the region. The EPA has

examined the State total emissions and

emissions density projected by OTAG to

2007, as described in section B.2, OTAG

Strategy Modeling. Both of these

measures of emissions (i.e., total and

density) are important considerations

for ozone formation. Total emissions

indicate the amount of mass emitted by

a State while emissions density

indicates the degree to which those

emissions are concentrated within the

State and provides a way to compare

emissions between geographically large

and small States on a more equivalent

basis. The State total emissions in Table

II–1 indicate that there is no single State

or group of adjacent States that stand

out as the major contributors to the total

manmade emissions in the OTAG

region. Rather, many States in the

Midwest, Northeast and Southeast have

high levels of emissions. For example,

Illinois, Indiana, Ohio, Kentucky,

Michigan, Pennsylvania, New York,

Alabama, Georgia, Florida, North

Carolina and Tennessee each have total

NOX emissions exceeding 1000 tons per

day. Even some other smaller States like

Connecticut, Delaware, Maryland,

Massachusetts, and Rhode Island, along

with the District of Columbia, have a

high spatial density of NOX emissions as

indicated in Table II–2. Thus,

considering the distribution of

emissions, a broad range of emissions

from many States contribute to the

regional background ozone during

episodic meteorological conditions. In

this situation, there is a cumulative

effect in that the thousands of stationary

sources and millions of motor vehicles

throughout the OTAG region

collectively cause downwind

contributions as they generate emissions

and those emissions interact over

multiple days.

1. OTAG Modeling Process

As described in the OTAG Modeling

Protocol (5), state-of-the-science models

and data bases were used in OTAG for

simulating the physical and chemical

processes involved in the formation and

transport of ozone and precursor species

over multiday episodes and regional

scales. As such, the OTAG modeling

system provides the most complete,

scientifically-credible tools and data

available for the assessment of interstate

transport. All of the OTAG model runs

were made for an area covering a large

portion of the Eastern United States, as

shown in Figure II–1. This area includes

all or portions of 37 States, the District

of Columbia and southern Canada. In

general, the OTAG ‘‘modeling domain’’

(i.e., OTAG region) was set large enough

to encompass the widespread spatial

extent of high ozone levels measured

during multiday episodes in the eastern

half of the United States. As such, the

domain is designed to handle the

synoptic (i.e., large) scale meteorological

conditions associated with regional

transport and to include the major

emissions source areas in the East. The

horizontal grid configuration used by

OTAG (see Figure II–1) includes a ‘‘Fine

Grid’’ at 12 km resolution ‘‘nested’’

within a ‘‘Coarse Grid’’ at 36 km

resolution. The size and location of the

‘‘Fine Grid’’ was determined based on

the location of areas with high ozone

concentrations, the geographic

variations in emissions density, the

meaningful resolution of some model

inputs, computer hardware limitations,

and model run times. As described in

section B.3, OTAG Geographic

Modeling, OTAG applied different

levels of controls in the ‘‘Fine Grid’’

versus the ‘‘Coarse Grid’’ as part of the

round-3 modeling.

Four specific episodes were selected

by OTAG for model simulations in order

to provide information on a range of

meteorological conditions which occur

during periods of elevated ozone levels.

These episodes are: July 1–11, 1988;

July 13–21, 1991; July 20–30, 1993 and

July 7–18, 1995. Each of these episodes

represents somewhat different episodic

characteristics in terms of transport

patterns and the spatial extent of high

ozone concentrations in the East (6).

The 1988 and 1995 episodes featured

high ozone concentrations in the

Northeast, Midwest, and Southeast with

wind regimes that provided the

meteorological potential for intra- and

inter-regional transport. During the 1991

episode, high ozone was confined

mainly to the northern portion of the

OTAG domain, whereas the 1993

episode was a ‘‘Southeast’’ episode with

relatively low ozone levels outside this

region. It should be noted that none of

the OTAG episodes include extensive

periods of high ozone in the far western

portions of the domain nor in areas

along the gulf coast.

As part of OTAG, an objective

evaluation of model predictions was

conducted for each of these four

episodes in order to determine the

performance of the modeling system for

representing regional ozone

concentration levels. This evaluation

focused on a number of statistical

metrics comparing predicted ozone to

ground-level ozone measurements (7).

The results indicate generally good

agreement between simulated and

observed values. Most importantly,

areas of predicted high ozone

correspond to areas of observed high

ozone. However, a few relatively minor

concerns were found, such as:

• A tendency to underestimate

concentrations in the North and

overestimate concentrations in the

South;

• Concentrations at night are

somewhat underestimated relative to

daytime predictions;

• Low observed concentrations tend

to be overestimated and higher observed

values tend to be underestimated; and

• Concentrations at the start of the

episode tend to be underestimated with

a tendency for concentrations at the end

of the episode to be overestimated.

The success of the model for

predicting pollutant concentrations aloft

is also important from a transport

perspective. During the day, when the

atmosphere is ‘‘well mixed,’’ groundlevel ozone values can serve as a good

measure of both local formation and

transport. However, at night, ozone is

depleted in a very shallow layer near

the ground due to deposition and

nighttime chemical reactions. Thus,

during the overnight and early morning,

ground-level measurements and

predictions do not adequately reflect

pollutant transport. Aircraft-measured

pollutant data and model predictions

during these periods indicate moderate

to high levels of ozone aloft which can

then mix down during the day and

further elevate ground-level

concentrations. A limited amount of

measured data aloft are available from

non-OTAG field studies for several of

the days in the 1991 and 1995 episodes.

An initial comparison of these data to
60332 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

5Although the OTAG assessments focussed on 1-

hour concentrations, the impacts on 8-hr average

concentrations were found to be similar to these for

1-hour values.

the model predictions (6) indicates that

model performance aloft is not as good

as for ground-level ozone. In general,

the model tends to underestimate ozone

aloft. This suggests that the model may

somewhat underestimate the amount of

ozone transport aloft, especially

overnight into the early morning hours.

Thus, the contribution of upwind source

regions to ozone levels in downwind

areas may actually be greater than

estimated by the model.

2. OTAG Strategy Modeling

The OTAG strategy modeling was

conducted in several phases. In each

phase, the effects on ozone 5 of various

changes in emissions were examined

relative to a future-year baseline. This

baseline reflects the projection of

emissions from 1990 to 2007. Included

in the 2007 baseline are the net effects

of growth and specific control programs

prescribed in the 1990 Amendments.

The control measures included in the

2007 baseline are listed in Table II–3.

Overall, domainwide emissions of NOX

in the 2007 baseline are approximately

12 percent lower than 1990 while

emissions of VOC are approximately 20

percent lower. The procedures for

developing the 1990 base inventory and

the 2007 baseline are described by

Pechan (8). The key findings (6) from

comparing the model predictions for the

2007 baseline to the 1990 base case

scenario are:

• Ozone levels are generally reduced

across most of the region, including

nonattainment areas;

• Some increases in ozone are

predicted in areas where higher

economic growth is expected to occur,

especially in the South;

• Ozone levels aloft along regional

‘‘boundaries’’ are reduced, but average

concentrations above 100 ppb and peak

concentrations above 120 ppb are still

predicted on several days; and

• Ozone concentrations above the 1-

hr and/or 8-hr NAAQS may still occur

in the future under similar

meteorological conditions in many of

the counties currently violating either or

both of these NAAQS.

The 2007 baseline emissions were

reduced in an initial set of sensitivity

modeling performed to assess several

broad strategy-relevant issues. All of

these model runs involved ‘‘across-theboard’’ emissions reductions (i.e., no

source category-specific reductions).

The results (6) of these simulations are

as follows:

• Regional reductions in NOX

emissions decrease ozone across broad

portions of the region including ozone

in areas violating the NAAQS;

• Regional reductions in VOC

emissions decrease ozone in and near

the core portions of urban areas with

relatively small regional benefits;

• Both elevated and low-level NOX

reductions decrease ozone

concentrations;

• NOX reductions can produce

localized, transient increases in ozone

(mostly due to low-level, urban NOX

reductions) in some areas on some days;

most increases occur on days and in

areas where ozone is low (i.e., below the

NAAQS);

• NOX plus VOC reductions lessen

ozone increases in urban areas, but

provide little additional regional

benefits compared to NOX-only

reductions; and

• The magnitude and spatial extent of

changes in 8-hour ozone concentrations

are consistent with the changes

predicted in 1-hour concentrations.

Based upon the findings of the

sensitivity runs, OTAG subsequently

developed and simulated sourcespecific regionwide control strategies in

two rounds of modeling. These

strategies were derived from a range of

control measures applied to individual

source categories of VOC and NOX (8).

The controls were grouped into various

levels of relative ‘‘stringency’’ as listed

in Tables II–4a and II–4b. The round-1

and round-2 modeling consisted of

strategies that contained various

combinations of controls from the least

(level ‘‘0’’) to most stringent (level ‘‘3’’)

for each source category. The control

levels and domainwide emissions

associated with these strategies are

given in Tables II–5a and II–5b.

The round-1 modeling was a

‘‘bounding analysis’’ with runs that

ranged from the lowest level of control

on all source categories (Run 1) to the

highest level of control on all sources

(Run 2). Runs 3 and 4b were included

to isolate the effects of the most

stringent OTAG controls on utilities

only, versus this level of control on the

other source categories. In the round-2

modeling, eight runs were simulated to

examine the relative benefits of

progressively increasing the level of

control on utilities, under two

alternative levels of control applied to

area, nonroad and mobile sources. The

results (6) of the round-1 and round-2

modeling are given in Table II–6.

The findings from the round-1 and

round-2 OTAG strategy modeling which

are particularly relevant to this analysis

are:

• Clean Air Act programs will likely

provide a reduction in ozone

concentrations in many nonattainment

areas; however, some areas currently in

nonattainment will likely remain

nonattainment in the future and new 8-

hr nonattainment and/or maintenance

problem areas may develop as a result

of economic growth in some areas;

• NOX reductions from elevated and

low-level sources are both beneficial

when considered on a regional basis;

and

• Further mitigation of the ozone

problem will require regional NOXoriented control strategies in addition to

local VOC and/or NOX controls

necessary for attainment in individual

areas.

3. OTAG Geographic Modeling

In the round-1 and round-2 strategy

modeling, controls were applied across

the entire domain. In round-3, controls

were applied on a geographic basis in

order to assess the relative effects of

different strategies in various portions of

the region. Prior to developing these

strategies, a series of sensitivity tests

was conducted by OTAG to provide

information on the spatial scales of

transport in order to help determine

where to apply various levels of control.

The most relevant tests are the

‘‘subregional’’ modeling and the

‘‘rollout’’ modeling. The base case for

these tests was the 2007 baseline

scenario. In the subregional modeling,

the domain was divided into the 12

subregions shown in Figure II–2. For

one set of subregional modeling, all

anthropogenic emissions were

eliminated from each subregion,

individually in separate model runs.

These runs, called the ‘‘zero-out’’

subregional scenarios, were performed

for the 1988 and 1995 episodes. In a

second set of subregional modeling,

emissions were reduced, but not

eliminated in each subregion. The level

of reductions were 60 percent for

elevated point-source NOX emissions,

30 percent from all other sources of

NOX, and 30 percent from all sources of

VOC. These runs are referred to as the

‘‘5c’’ subregional scenarios. The ‘‘5c’’

scenarios were run for most, but not all,

subregions for the 1988, 1991 and 1995

episodes. In addition to looking at

individual subregions, there were runs

for 1988 and 1991 which applied the

‘‘5c’’ reductions in subregions 5, 6, and

9 (Figure II–2) combined in order to

determine the relative impacts of

expanding the size of the area of

emissions reductions.

In the rollout modeling, the ‘‘5c’’

emissions reductions were applied first

within selected areas and, then, outward
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60333

in incremental steps (rollouts) of

approximately 200 km from these areas,

in subsequent runs. Three major

nonattainment areas in the region

(Atlanta, the Lake Michigan Area, and

New York City) were selected by OTAG

for this type of modeling.

The results (6) of the OTAG

geographic modeling indicate the

following:

• Emissions reductions in a given

multistate region/subregion have the

most effect on ozone in that same

region/subregion;

• Emission reductions in a given

multistate region/subregion also affect

ozone in downwind multistate regions/

subregions;

• Downwind ozone benefits decrease

with distance from the source region/

subregion (i.e., farther away, less effect);

• Downwind ozone benefits increase

as the size of the upwind area being

controlled increases, indicating that

there is a cumulative benefit to

extending controls over a larger area;

and

• Downwind ozone benefits increase

as upwind emission reductions increase

(the larger the upwind reduction, the

greater the downwind benefits).

The round-3 strategies were based in

large part on the results of the

geographical sensitivity runs. The

cornerstone of round-3 was a set of

geographic ‘‘zones’’ (see Figure II–3)

which was used to vary the level of

control across the OTAG region. For the

most part, OTAG focussed the round-3

controls on zones in the ‘‘Fine Grid.’’

This was based upon an analysis

indicating that, in general, the greatest

potential for regional transport leading

to inter-state impacts of concern occurs

within the ‘‘Fine Grid’’ portion of the

OTAG region. The individual zones

were used to differentiate the impacts of

controls in and close to the three major

1-hour nonattainment areas of the ‘‘Fine

Grid’’ (i.e., the Northeast Corridor,

Atlanta, and Chicago/Milwaukee) versus

controls in zones farther upwind of

these areas. Specifically, in round-3

various levels of utility and nonutility

controls were applied by zone in

different runs. The level of control for

each strategy is given in Table II–7. In

general (except for Run F), the round-3

runs progressively increase the level

and spatial extent of utility and

nonutility controls starting with the

reference run (Run A) through the most

stringent run (Run I). In addition, there

were a number of supplemental round3 runs (6) performed using a modified

version of the zones. The most relevant

of these were Runs CA and CB which

altered the configuration of zones II, III,

and IV to correspond more closely to the

borders of the OTR.

The results (6) of the OTAG round-3

runs indicate the following:

• The greater the emissions

reductions the greater the ozone benefits

(Run I was the most effective strategy

and Run A the least);

• There was no bright-line between

the incremental application of controls

nor any leveling off of benefits with the

more stringent controls;

• Increasing the spatial extent of

emissions reductions increases the

amount and spatial extent of ozone

benefits downwind; areas farther

upwind may need a higher level of

control to have a given effect in a

particular downwind area;

• In general, emissions reductions in

a given zone have the greatest effects

within that zone; but there are also

impacts on high ozone concentrations in

other zones downwind;

• Emissions reductions in zones I, III,

and V are ‘‘effective and necessary’’ (6)

to reduce ozone in the Lake Michigan

area, the Northeast Corridor, and

Atlanta, respectively which are the

closest downwind areas to each of these

zones;

• Emissions reductions in more

distant zones also help reduce ozone in

these three major nonattainment areas;

emissions reductions in zone II benefit

the Northeast Corridor and the Lake

Michigan area; emissions reductions in

zone IV benefit Atlanta and the Lake

Michigan area;

• Emissions reductions in zones II

and IV are also ‘‘effective and

necessary’’ (6) to reduce ozone in

‘‘problem areas’’ within these zones

(e.g., Birmingham, Nashville, Charlotte,

Richmond, Louisville, and Cincinnati);

• When viewed on a regional basis, it

may be ‘‘difficult to geographically

distinguish between control levels’’ (6)

because there are ozone problem areas

in every zone within the ‘‘Fine Grid’’

and there are clearly interzonal impacts;

• Additional emissions reductions in

‘‘Coarse Grid’’ States ‘‘are not very

effective’’ (6) in reducing high ozone

levels downwind in problem areas of

the ‘‘Fine Grid’’; and

• Although the OTAG assessments

focused on 1-hour concentrations, the

impacts on 8-hour average

concentrations were found to be similar

to those for 1-hour peak values,

suggesting that ‘‘a regional strategy

designed to help meet’’ the 1-hour

NAAQS ‘‘will also help meet’’ the 8-

hour NAAQS (6).

Overall, the findings from the OTAG

sensitivity and strategy modeling

indicate that:

• Areas of high ozone, both measured

and predicted for the future, occur, or

will occur, in most portions of the

modeling domain;

• Several different scales of transport

(i.e., inter-city, intra-state, inter-state,

and inter-regional) are important to the

formation of high ozone in many areas

of the East;

• The greatest potential for inter-state

and inter-regional impacts associated

with transport occurs between States

within the multistate ‘‘Fine Grid’’ area;

• A regional strategy focussing on

NOX reductions across a broad portion

of the region will help mitigate the

ozone problem in many areas of the

East;

• There are ozone benefits across the

range of controls considered by OTAG;

the greatest benefits occur with the most

emissions reductions; there was no

‘‘bright line’’ beyond which the benefits

of emissions reductions diminish

significantly;

• Even with the large ozone

reductions that would occur if the most

stringent controls considered by OTAG

were implemented, there may still

remain high concentrations in some

portions of the OTAG region;

• A regional NOX emissions

reduction strategy coupled with local

NOX and/or VOC reductions may be

needed to enable attainment and

maintenance of the NAAQS in this

region.

It should be noted that urban-scale

analyses will be necessary in order for

States to develop local attainment plans.

These analyses will take into account

more geographically refined emissions

and local meteorological factors, such as

lake and sea breezes and/or topography.

Urban-scale modeling is also necessary

to more precisely evaluate the degree

and extent of any NOX disbenefit.

4. Other Relevant Analyses

In addition to the OTAG modeling

described above, the potential for

regional ozone transport has been

examined by the OTAG Air Quality

Assessment Work Group using

trajectory analyses, wind vector

characterization, and statistical analyses

of ozone measurements. The trajectory

analyses (9) were used to identify a

‘‘distance scale’’ indicative of the 1- to

2-day transport distance of ozone and

precursors. The results suggest that

ozone-laden air may travel distances of

150 miles to 500 miles or more into and

across the Midwest and Northeast.

Analyses, as part of the Southern

Oxidants Study (10), indicate that most

southern episodes may be more closely

linked to near-stagnation conditions and

thus, shorter transport distances might
60334 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

be expected within the Southeast.

Additional information on regional

transport patterns comes from an

analysis conducted by OTAG to

characterize the regional wind flow

patterns typically associated with high

ozone in the Northeast, Southeast, and

Midwest (9). These wind vectors (Figure

II–4) indicate that regional episodes are

typically associated with broad-scale

anticyclonic (i.e., clockwise) flow

regimes centered over the OhioTennessee Valley area. Under these

conditions, there are typically lighter

winds and weaker transport within the

South compared to other regions.

However, the information also indicates

the potential for transport from the

South to other portions of the region.

For example, in the Midwest, high

ozone is generally associated with wind

flows from States located to the south

and southwest. For the Northeast, the

data suggest a strong westerly flow

favoring transport from States farther to

the west.

Another method for estimating the

potential range of transport was

developed by Rao (11) based on

correlating daily ambient ozone

measurements between monitoring sites

for the period 1985 through 1994 for

several nonattainment areas (i.e.,

Atlanta, Washington DC, Cincinnati,

Pittsburgh and Chicago). The analysis

indicates the presence of ‘‘ozone

clouds’’ surrounding these areas which

are likely the result of pollutant

transport, spatial patterns in emissions,

and weather conditions conducive to

ozone formation. The spatial extent of

these ‘‘ozone clouds’’ is on the order of

300 miles or more, extending from the

central portion of the nonattainment

area along the axis of the major

transport direction.

The importance of mitigating

transported ozone for solving the

nonattainment problem for many cities

in the East has been examined as part

of ongoing urban scale modeling

analyses by various State agencies. In

urban scale modeling, transport into the

nonattainment area is represented by

specifying pollutant concentrations

along the sides and top of the modeling

domain. These ‘‘boundary condition’’

concentrations reflect ozone transport

into the urban area at the surface and

aloft. As such, incoming ozone (as well

as precursor chemical species) moves

into the urban area and mixes with local

emissions to increase the formation of

ozone. The available urban scale

modeling work is summarized in a

report commissioned by OTAG (12). It

should be noted that these modeling

analyses were conducted to address 1-

hour attainment problems. Still, the

information is expected to be generally

applicable to 8-hour ozone

concentrations as well. The findings

from this report which are relevant

include:

• New York City—a reduction in

transport into the New York area

associated with upwind emissions

reductions on the order of 75 percent for

NOX and 25 percent for VOC along with

local VOC and NOX reductions may be

needed for attainment in New York;

• Philadelphia—transport appears to

be a major component in peak ozone

concentrations in the Philadelphia

domain, contributing 90 percent to the

peak in one of the scenarios modeled;

• Lake Michigan—transported ozone

levels coming into the Lake Michigan

area contribute 40–60 percent to the

peak concentration downwind of urban

centers in this area; background

concentrations in the range of 80–100

ppb may need to be reduced to around

60 ppb for attainment in this region;

• Southeast Michigan—ozone

transport into this area ‘‘contributed

significantly to the simulated peak

ozone concentrations on many of the

episode days;

• St. Louis—predicted ozone

concentrations in this area are sensitive

to incoming levels of ozone/precursor

transport;

• Atlanta—the amount of ozone

transported into the area was found to

be one of the factors contributing to the

difficulty for this area to demonstrate

attainment;

• Richmond—transported ozone

contributes to predicted high ozone on

certain episode days, and regional

controls on upwind sources may be

necessary to reduce ozone in this area

during some of the episode days

modeled;

• Charlotte—transported ozone

appears to be a ‘‘significant component’’

of ozone in the area during some

episodes, particularly with winds from

a northerly direction; and

• Nashville—transported ozone was

predicted to be a major contributor to

ozone in this area on 1 of the 2 high

ozone days modeled.

In addition to the preceding

qualitative analyses, there are several

non-OTAG regional modeling analyses

which provide information on interstate

contributions due to transport. First,

modeling by EPA for the OTC, using the

Regional Oxidant Model (ROM),

examined the impact of controls outside

the OTR on ozone within this

region (13). The results indicate that a

0.15 lb/MMBtu NOX emissions limit on

certain stationary sources outside the

OTR, together with other controls,

would likely have the following effects

within the OTR:

• Reductions of up to 15–18 ppb in

daily maximum 1-hour ozone in the

western part of the OTR, and

• Reductions of up to 6–9 ppb along

the Northeast Corridor from

Washington, DC to northern New Jersey.

Second, a new modeling technique,

the ‘‘Comprehensive Air-quality Model

with extensions’’ (CAMx), has been

developed (14) in an attempt to identify

the contribution of upwind source areas

to specific downwind locations. The

Ozone Source Apportionment

Technology (OSAT) in CAMx was used

by the Midwest Ozone Group (MOG) to

quantify the contributions of emissions

from upwind sources on high ozone

concentrations in the Northeast Corridor

and the Lake Michigan area. The CAMx

analysis modeled the OTAG July 1991

episode only and considered 1-hour

ozone predictions above two cut-points:

100 ppb and 120 ppb. Also, the MOG

CAMx report (14) did not examine the

contributions from emissions in

individual upwind States, but rather,

the analysis examined the impacts of

emissions from concentric geographic

‘‘rings’’ upwind of the Northeast

Corridor and Lake Michigan areas. In

general, the results are consistent with

the OTAG geographic sensitivity

modeling in that much of the

contribution to ozone in a particular

multistate area comes from sources

within that same multistate area,

considerable contributions also come

from sources outside the multistate area,

and anthropogenic NOX emissions in

upwind areas contribute much more to

transport than upwind VOC emissions.

Some of the findings from the CAMx

analysis relative to the contributions to

high ozone in the Northeast Corridor

and Lake Michigan area are as follows:

• On average, nearly 50 percent of the

high ozone levels in these two areas

come from upwind (mostly NOx)

sources;

• On average, for the Northeast

Corridor a large portion (90 percent) of

the contribution from upwind sources

comes from States to the west and south

within approximately 390 km of the

Corridor (this may include all or

portions of States as far upwind as Ohio,

North Carolina, and West Virginia);

nearly all (95 percent) of the

contribution comes from upwind

sources within approximately 570 km of

the Corridor (this may add portions of

Kentucky, Tennessee, and South

Carolina as potential upwind

contributors);

• On average, for the Lake Michigan

area a large portion (90 percent) of the

contribution from upwind sources
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60335

comes from States to the west and

southwest within approximately 650 km

of this area (this may include all or

portions of States as far as Iowa,

Minnesota, Missouri, and Tennessee);

nearly all (95 percent) of the

contribution comes from upwind

sources within approximately 770 km of

the Lake Michigan area (this adds

portions of Arkansas, Kansas, Nebraska,

North Dakota, and South Dakota); and

• Transport distances for individual

high ozone days are even longer, in

some cases, than the episode averages

indicated above.

A third non-OTAG modeling study

that is relevant to this assessment was

performed by a group of northwest

OTAG States (Iowa, Minnesota,

Nebraska, North Dakota, and South

Dakota) (15). One part of this study

included modeling similar to the OTAG

subregional modeling, except that ‘‘zeroout’’ and ‘‘5c’’ emissions reductions

were applied in various combinations in

these States only, using the OTAG July

1995 episode. In these runs, emissions

in all other States in the OTAG region

were simulated with the 2007 baseline

emissions. The modeling results were

analyzed in terms of the contributions of

emissions in these five States to daily

maximum 1-hour ozone above 100 ppb

in downwind areas. The results indicate

the following:

• Emissions in Minnesota, Nebraska,

North Dakota, South Dakota, and the

‘‘Coarse Grid’’ portion of Iowa (see

Figure II–1) collectively contribute less

than 2 ppb to downwind ozone above

100 ppb; and

• Emissions from these States

including the ‘‘Fine Grid’’ portion of

Iowa, contribute in the range of 2 to 6

ppb to ozone above 100 ppb in grid cells

downwind near Lake Michigan, Detroit,

and Cincinnati.

Collectively, the studies cited here

indicate that:

• The meteorological conditions and

air trajectories during regional-scale,

high ozone episodes provide the

potential for multistate ozone transport;

• Ambient measurements indicate

that ozone episodes can have a large

multistate spatial extent within which

1-to 2-day transport may occur;

• Examination of emissions data

indicates that numerous sources of NOX

may be contributing to high regional

background ozone concentrations;

• State urban-scale modeling analyses

for areas in various portions of the

OTAG region indicate that transport

from upwind areas is an impediment to

attainment of the NAAQS;

• Regional modeling studies indicate

contributions to high ozone in the

Northeast Corridor and the Lake

Michigan area may come from States as

far away as 570 km and 770 km,

respectively; and

• Non-OTAG multistate modeling

indicates that emissions from States in

the northwest portion of the ‘‘Coarse

Grid’’ may not make large contributions

to high ozone in downwind States

elsewhere in the OTAG region.

C. Technical Analysis of Significant

Contribution

1. Criteria for Determining Significant

Contribution

Whether a contribution is

‘‘significant’’ depends on the overall

context. There may be no single amount

of contribution which could be

considered as a bright line indicator of

‘‘significant’’ that would be applicable

and appropriate in all circumstances. As

described above, under one

interpretation of the CAA’s section

110(a)(2)(D), factors to be considered in

determining whether a contribution is

significant include:

• The level of emissions in the area

upwind of a nonattainment area;

• The amount of the contribution

(ppb above the level of the standard)

made to the downwind nonattainment

area;

• The transport distance between the

upwind source area and the downwind

problem area; and

• The geographic extent of the

contribution downwind. For example,

ozone is generally the result of

emissions of NOX and VOC from

hundreds of stationary sources and

millions of vehicles, each of which is

likely to be responsible for much less

than 1 percent of the overall inventory

of precursor emissions. A source or

group of sources should not be

exempted from treatment as a

significant contributor merely because it

may be a small part, in terms of total

emissions, of the overall problem when

all or most other contributors,

individually, are also relatively small

parts of the overall problem. This

situation, in which a number of

individual (and sometimes small)

sources collectively cause a significant

impact, is a major aspect of the

contribution issue. The moderate-tohigh ozone levels which cover broad

regions are the result of emissions from

millions of individual sources

interacting over multiple days. The

contribution to downwind

nonattainment results from the

cumulative contribution from all

sources involved in this process. Given

these issues, it is not appropriate to

define a bright line test for ‘‘significant

contribution.’’ Rather, EPA is using a

‘‘weight of evidence’’ approach, based

on a range of information, for

determining whether a State makes a

significant contribution to downwind

nonattainment. The EPA is also

proposing a second, alternative

interpretation to section 110(a)(2)(D),

under which the weight of evidence

approach incorporates other factors,

including the relative costs of

controlling downwind emissions, as

described in section I.D.2.b., Significant

Contribution to Nonattainment.

2. Overview of Technical Approach

The findings from the relevant

background studies and the OTAG

modeling results provide a basis for

concluding that ozone transport results

in interstate contributions to high ozone

levels during multiday episodic

conditions within portions of the OTAG

region. An overview of the approach for

analyzing this information in an

assessment of States that make a

significant contribution to downwind

nonattainment is as follows:

• The air quality and modeling

analyses cited in section B.4, Other

Relevant Analyses, were considered in a

qualitative manner to identify, from a

regional perspective, States which may

contribute to multistate transport;

• The results of the OTAG

subregional modeling runs were used to

quantify the extent that each subregion

contributes to downwind nonattainment

for the 1-hour and/or 8-hour NAAQS;

and

• State NOX emissions data were used

to translate the findings from the

subregional modeling to a State-by-State

basis.

The specific model runs used in this

analysis include the ‘‘zero-out’’ runs in

which all anthropogenic emissions from

individual subregions (comprised of

portions of small groups of States) are

removed, and the contributions to

downwind ozone are predicted. This set

of model runs was chosen since it

provides an appropriate way to quantify

the contribution of the full set of

anthropogenic emissions in one area to

ozone concentrations in another. As

described in section B.2, OTAG Strategy

Modeling, zero-out runs were made for

the 1988 and 1995 episodes only. The

results for both episodes were combined

in this assessment. Also, the analysis of

emissions data focussed on NOX since

the OTAG and non-OTAG modeling

results indicate that NOX emissions

reductions lower ozone transport across

broad portions of the OTAG region,

whereas, VOC emissions reductions

have primarily local benefits.

The air quality, modeling, and

emissions information was used
60336 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

6 Values above 124 ppb are considered to be

exceedances of the 0.12 ppm 1-hour ozone NAAQS

in view of the rounding convention established for

monitoring data whereby ozone concentrations

between 125 ppb and 129 ppb are rounded up to

0.13 ppm.

collectively to determine, based on the

weight of evidence, which States make

a significant contribution to downwind

nonattainment.

3. Identification of Ozone ‘‘Problem

Areas’’

As described above, in order to

quantify the contribution from upwind

States to nonattainment downwind,

EPA identified areas which currently

have a 1-hour and/or 8-hour ozone

nonattainment problem and are

expected to continue to have a

nonattainment problem in the future,

based on modeling. In addition, EPA

considered areas which may have a

future maintenance problem for the 8-

hour NAAQS. For current

nonattainment areas, EPA used air

quality data for the period 1993 through

1995 to determine which counties are

violating the 1-hour and/or 8-hour

NAAQS. These are the most recent 3

years of fully quality-assured data

which were available in time for this

assessment. A list of these counties is

provided in Tables II–8a and II–8b. The

EPA is reviewing more recent air quality

data for 1996 and 1997. In the event that

these data alter the results of this

assessment in any meaningful way, EPA

will make the appropriate adjustments

to the findings. Concerning projected

future nonattainment areas, EPA used

the OTAG model predictions for the

2007 baseline, as described in section

II.C.5, Approaches for Analyzing

Subregional Modeling Data. For ease of

communication, the technical

discussions frequently use the term

‘‘nonattainment’’ to refer to these areas.

It should be noted that this use of the

term ‘‘nonattainment’’ in reference to a

specific area is not meant as an official

designation or determination as to the

attainment status of the area.

4. Analysis of Air Quality, Trajectory,

and Non-OTAG Modeling Information

The EPA examined the findings from

the air quality, trajectory, and nonOTAG modeling analyses in section B.4.

to identify certain States which may

potentially contribute to nonattainment

in downwind areas. First, EPA applied

both the lower and upper ends of the

OTAG transport distance scale (i.e., 150

miles and 500 miles (9)) to 1-hour

nonattainment areas in the northern half

of the OTAG region. Using the lower

end of the transport scale indicates that

the following States and Washington DC

may potentially contribute to ozone in

downwind nonattainment areas:

Connecticut, Delaware, Illinois, Indiana,

Kentucky, Maine, Maryland,

Massachusetts, Michigan, New

Hampshire, New Jersey, New York,

Ohio, Pennsylvania, Rhode Island,

Tennessee, Virginia, West Virginia,

Wisconsin and Vermont. Using the

upper limit of transport distance

indicates that the following additional

States may potentially contribute to

downwind nonattainment areas:

Alabama, Arkansas, Georgia, Iowa,

Kansas, Minnesota, Mississippi,

Missouri, Nebraska, North Carolina,

Oklahoma and South Carolina. Also,

examining the findings from the nonOTAG regional modeling results (13, 14,

15) indicates that collectively, a large

portion of the contributions to high

ozone in the Northeast Corridor and/or

the Lake Michigan area may come from

States as far upwind as: Missouri, North

Carolina, Ohio, Tennessee and West

Virginia.

5. Approaches for Analyzing

Subregional Modeling Data

The subregional modeling runs

provide a method to quantify the

amount of contribution by upwind

States to downwind nonattainment.

Four approaches were included in the

analysis of subregional modeling

results. Approaches 1 and 2 were

designed to address the contribution to

1-hour nonattainment and Approaches 3

and 4 the contribution to 8-hour

nonattainment. Approaches 1 and 3

examine the contributions in areas

which have both monitored and

modeled nonattainment. Approaches 2

and 4 examine the contributions in

areas with modeled nonattainment. The

rationale for each approach is described

below.

a. Approaches for 1-Hour

Nonattainment. Approach 1 was

designed to focus on contributions to

areas that have an observed 1-hour

ozone problem and in which the model

predicts an ozone problem. In this

regard, the analysis was restricted to

those grid cells in the domain that had

1-hour daily maximum ozone

predictions ≥125 ppb 6 in the 2007

baseline, and were within one of the

counties currently violating the 1-hour

NAAQS. However, the requirement that

high ozone predictions spatially

coincide with violating counties may be

overly restrictive given the uncertainties

in the modeled wind regimes associated

with the regional nature of the

meteorological inputs. Also, the analysis

was limited to only two episodes, only

one of which, July 1995, actually

occurred during the 3-year period used

to identify the violating counties.

Another limitation of Approach 1 was

that it excludes all grid cells that are

over water and not touching any State

land areas. This may be too restrictive

since, in the real atmosphere, sea breeze

and lake breeze wind flows can

transport high ozone levels that occur

over water back on-shore to affect

coastal land areas. This meteorological

process, often associated with high

ozone along the shoreline of Lake

Michigan and along the New England

coast, is not adequately treated by the

regional scale meteorological inputs

used in OTAG. Thus, high

concentrations predicted just offshore

may be inappropriately excluded from

the analysis. Approach 2 was designed

to address these concerns. In this

approach, all grid cells over land that

had a 1-hour daily maximum ozone

prediction ≥125 ppb in the baseline

were included. Also included were grid

cells with predictions ≥125 ppb over

each of the Great Lakes and in a band

60 km (5 grid cells) wide along the East

Coast.

b. Approaches for 8-Hour

Nonattainment. The two approaches for

assessing contribution for 8-hour

nonattainment were similar in design to

those used for 1-hour nonattainment.

However, the inconsistency between the

form of the 8-hour NAAQS, which

considers 3 years of data, and the

limited predictions available from the

OTAG episodes introduced a

complication to the analysis. Basically,

it was not possible to use the model

predictions in a way that explicitly

matches the 3-year average of the 4th

highest 8-hour form of the NAAQS.

Instead, an analysis was performed to

link the model predictions to the

NAAQS as closely as possible. This

analysis consisted of comparing the

average 4th highest 8-hour

concentrations, based on 3 years of

ambient data, to the average 1st, 2nd,

3rd, and 4th highest 8-hour values using

ambient data limited to the three most

recent OTAG episodes (i.e., 1991, 1993,

and 1995). The results of this analysis

indicate that the average of the episodic

2nd highest 8-hour ozone concentration

corresponds best, overall, to the average

of the 4th highest 8-hour NAAQS.

Approach 3 is intended to focus on

the contributions to areas that have an

observed 8-hour ozone problem and

where the model predicts an 8-hour

ozone problem. The analysis for this

approach was restricted to those grid

cells in the domain that had an average

(over the 1988 and 1995 episodes) 2nd

high 8-hour ozone prediction ≥85 ppb in

the 2007 baseline, and were within one

of the counties currently violating the 8-
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60337

hour NAAQS. The same technical

concerns and limitations discussed

above for Approach 1 are also

applicable to Approach 3. To address

these concerns for the 8-hour analysis,

Approach 4 was constructed to include

all grid cells that had an average 2nd

high 8-hour ozone prediction ≥85 ppb

over land areas, the Great Lakes, and in

the offshore waters, as in Approach 2 for

the 1-hour NAAQS. In addition, by

including all grid cells with predicted

nonattainment in 2007, Approach 4

provides a way to consider areas which

are currently measuring attainment, but

which may become nonattainment for

the 8-hour NAAQS in the future.

c. Methods for Presenting 1-Hour and

8-Hour Assessments. All of the

approaches for both 1-hour and 8-hour

nonattainment quantify the impacts of

emissions in each subregion on ozone

concentrations in downwind States (i.e.,

States outside the particular subregion).

It should be noted that the calculated

contributions represent the impacts

from individual upwind subregions and

not the cumulative impacts from

multiple subregions, which would be

even greater in magnitude. In

Approaches 2 (1-hour) and 4 (8-hour),

grid cells off the East Coast were added

to the totals of the adjacent States,

whereas the impacts for areas over each

of the Great Lakes were tabulated

separately. In all cases, the ozone

impacts were quantified by calculating

the difference in predicted ozone

between each subregional zero-out run

and the 2007 baseline scenario. The

contributions from emissions in each

subregion to nonattainment in

downwind States are summarized for all

approaches in Tables II–9a and II–9b.

This summary shows the contributions

in terms of both the frequency of

impacts and the number of downwind

States impacted for specific

concentration ranges, as described

below. More detailed information

including the contributions to

individual States is provided in Tables

II–10 through II–13, for Approaches 1

through 4, respectively. The

contributions are grouped into one of

six ranges: >2 to 5 ppb, >5 to 10, >10

to 15, >15 to 20, >20 to 25, and >25 ppb.

A value of 2 ppb was chosen as the

minimum level for this analysis

following the convention generally used

by OTAG for evaluating the impacts of

emissions changes. As an example,

Table II–10 shows the frequency of

contributions from each subregion to

nonattainment in downwind States for

Approach 1. Note that the frequency of

contributions for the 1-hour NAAQS is

determined by tallying the total

‘‘number of days and grid cells’’ with

impacts within the specified range.

However, the frequency of contributions

for the 8-hour NAAQS includes the total

‘‘number of grid cells’’ only. That is, the

averaging procedure used to reflect the

form of the 8-hour NAAQS results in a

single ‘‘average’’ value for each grid cell,

instead of values for each day modeled.

In the following sections, Approach 1

and Approach 3 are referred to as the

‘‘violating-county’’ approaches, whereas

Approach 2 and Approach 4 are referred

to as the ‘‘all grid-cell’’ approaches for

the 1-hour and 8-hour NAAQS,

respectively. Also, as mentioned

previously, the term ‘‘nonattainment’’ is

used to refer to those areas (grid cells)

which meet the criteria for a given

approach. For example, in the analysis

of Approach 1, ‘‘nonattainment’’ refers

to those areas which have both

measured violations and model

predictions of 1-hour ozone ≥125 ppb.

6. Contributions to 1-Hour

Nonattainment

The information from the subregional

modeling analyses provided in Tables

II–10 and II–11 were examined from

both a ‘‘receptor’’ and ‘‘source’’

perspective. The results for the ‘‘countyviolation’’ approach (Approach 1—

Table II–10) and the ‘‘all grid-cell’’

approach (Approach 2—Table II–11) are

both considered. Examining the data in

Table II–10 indicates that many

nonattainment areas are affected by

multiple source areas. Considering the

impacts on violating counties indicates,

for example, that:

• Nonattainment areas in

Pennsylvania receive contributions of

more than 2 ppb from Midwest and

Southeast States located in five

subregions (2, 5, 6, 7, and 8) with

contributions over 25 ppb from States in

subregions 6 and 7;

• Nonattainment areas in New Jersey

receive contributions of more than 2

ppb from Midwest States as well as

adjacent States in six subregions (1, 2,

3, 5, 6, and 7) with contributions over

25 ppb from subregions 3 and 7;

• Nonattainment areas in Maryland

receive contributions of more than 2

ppb from Midwest States and adjacent

States in six subregions (1, 2, 3, 4, 5, and

6) with contributions in the range of 15

to 20 ppb from subregions 3 and 6;

• Nonattainment areas in Illinois

receive contributions of 5 to 10 ppb

from Southeast States in subregion 9;

and

• Nonattainment areas in Georgia and

Alabama receive contributions of 15 to

20 ppb from Midwest States in

subregion 5 as well as from adjacent

Southeast States in subregion 8.

Considering the ‘‘all grid cell’’

approach increases the frequency and

magnitude of impacts, as would be

expected. For example, the

contributions from States in subregion 2

to nonattainment in Pennsylvania

increase to the range of 10 to 15 ppb;

contributions from Southeast States in

subregion 9 in the range of 2 to 5 ppb

are evident in nonattainment in

Maryland; and Midwest States in

subregions 1 and 5 contribute 5 to 10

ppb to nonattainment in Ohio.

As indicated above, the subregional

modeling results were also examined in

terms of the impact of each subregion on

ozone in downwind States outside the

particular subregion. The following

results highlight the contributions of

each subregion to downwind

nonattainment (see Tables II–10 and II–

11). Results are presented for the

‘‘violating county’’ approach (Approach

1) and supplemented with results from

the ‘‘all grid-cell’’ approach (Approach

2) to the extent that this later approach

adds key information to the findings.

Subregion 1 (portions of Illinois,

Wisconsin, Indiana, and Iowa):

emissions in this subregion contribute 2

to 5 ppb on numerous occasions to

nonattainment in violating counties in

four States along the Northeast Corridor

having serious or severe nonattainment

(i.e., Connecticut, Maryland, New

Jersey, and New York); downwind

contributions as high as 5 to 10 ppb are

evident near Detroit over Lake St. Clair,

as well as over Lakes Erie and Ontario

based on the ‘‘all grid-cell’’ approach.

Subregion 2 (portions of Michigan,

Indiana, and Ohio): emissions in this

subregion contribute 5 to 10 ppb to

nonattainment in violating counties in

five downwind States; contributions

over 10 ppb are evident in seven

downwind States from the ‘‘all grid-cell

approach.’’

Subregion 3 (portions of

Pennsylvania, New York and Delaware):

emissions in this subregion contribute

over 2 ppb to violating counties in nine

downwind States with contributions of

15 ppb or more in three States.

Subregion 4 (New Jersey, Connecticut

and portions of New York, Pennsylvania

and Delaware): emissions from this

subregion contribute more than 25 ppb

on numerous occasions to three

downwind States along the Northeast

Corridor.

Subregion 5 (portions of Illinois,

Indiana, Kentucky, Missouri, and

Tennessee): emissions from this

subregion contribute 2 to 5 ppb to

violating counties in three downwind

States along the Northeast Corridor with

contributions of over 10 ppb in three

other downwind States in the region;
60338 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

considering the ‘‘all grid-cell’’ approach

shows contributions of over 20 ppb to

the south in Alabama and 5 to 10 ppb

over Lakes Erie and St. Clair.

Subregion 6 (portions of Ohio,

Indiana, Kentucky, Tennessee, West

Virginia and Virginia): emissions in this

subregion contribute over 5 ppb to

violations in eight States (and as far

downwind as Massachusetts with the

‘‘all grid-cell’’ approach); contributions

over 15 ppb are predicted in two of the

eight States.

Subregion 7 (Maryland, Washington,

DC, and portions of Delaware, North

Carolina, Virginia and West Virginia):

emissions in this subregion contribute

more than 15 ppb to violating counties

in downwind States along the Northeast

Corridor with over 25 ppb contribution

on numerous occasions to two of these

States; the ‘‘all grid-cell’’ approach

indicates contributions from this

subregion to South Carolina as well as

to Kentucky and Ohio.

Subregion 8 (portions of North

Carolina, South Carolina and Georgia):

emissions in this subregion contribute 2

to 5 ppb to violating counties in four

States including several which are

relatively far downwind (i.e., Missouri

and Illinois) with contributions over 15

ppb to one other State; considering the

‘‘all grid-cell’’ approach indicates

contributions of over 10 ppb to two

States along the Northeast Corridor.

Subregion 9 (portions of Tennessee,

Georgia, Alabama, Mississippi, North

and South Carolina and Arkansas):

emissions in this subregion contribute

over 2 ppb to violating counties in four

downwind States with contributions

over 10 ppb in Indiana; contributions

over 10 ppb are evident in three

downwind States and far away as Lakes

Michigan from the ‘‘all grid-cell’’

approach.

Subregion 10 (Florida and portions of

Mississippi, Alabama, Georgia and

Louisiana): emissions in this subregion

do not contribute above 2 ppb to

violating counties in any other States;

considering the ‘‘all grid-cell’’ approach

indicates one occurrence of a

contribution in the range of 2–5 ppb.

Subregion 11 (portions of Texas,

Louisiana, Arkansas and Oklahoma):

emissions in this subregion contribute 2

to 5 ppb to violating counties in two

downwind States.

Subregion 12 (portions of Missouri,

Iowa, Wisconsin, Minnesota, North

Dakota, South Dakota, Nebraska, Kansas

and Oklahoma): emissions in this

subregion contribute 2 to 5 ppb in

violating counties in two downwind

States with 5 to 10 ppb contributions

also evident in one of these States (i.e.,

Michigan, including Lake Michigan).

The results presented in Tables II–10

and II–11, and discussed above, indicate

that in general, large contributions to

downwind nonattainment occur on

numerous occasions even though the

analysis was limited to only two

episodes. Although the level of

contribution varies from subregion to

subregion, a consistent pattern is

apparent. In view of the relatively high

magnitude of the contributions, and/or

the relatively high frequency of the

contributions, and/or the distance

downwind to which the contributions

occur, and/or the geographic extent of

the downwind contributions, EPA

believes that emissions from subregions

1 through 9 make a marked contribution

to 1-hour nonattainment in numerous

downwind States. Contributions to

downwind nonattainment were also

evident from subregions 10, 11, and 12,

although to a lesser magnitude and

extent.

7. Contributions to 8-Hour

Nonattainment

In general, the downwind

contributions to 8-hour nonattainment

are more geographically extensive than

those for 1-hour nonattainment. This is

not unexpected because there are many

more violating counties for the 8-hour

NAAQS and, likewise, the model

predicts ‘‘nonattainment’’ over a much

broader portion of the region. The

following examples illustrate the extent

and magnitude of contributions to

violating counties (Approach 3—Table

II–12) that are beyond what was found

for the 1-hour assessment:

• Contributions to nonattainment

areas in Pennsylvania from States in

subregion 2 are over 25 ppb rather than

2 to 5 ppb;

• In addition to the contributions

from States in subregions 1, 2, 3, 5, 6,

and 7 (ranging up to 15 to 20 ppb from

subregion 3), nonattainment areas in

New Jersey also receive a 2 to 5 ppb

impact from southeastern States in

subregion 8;

• Nonattainment areas in Illinois

receive contributions of 5 to 10 ppb

from States to the east in subregion 6

and south in subregion 9;

• Nonattainment areas in Ohio

receive contributions of 5 to 10 ppb

from States in five subregions in the

Midwest, Northeast, and Southeast (1, 3,

5, 7, 8, 9) with contributions over 10

ppb from States in subregion 5;

• Nonattainment areas in North

Carolina receive contributions of 5 to 10

ppb from two subregions (7 and 9) with

contributions of over 25 ppb from

Midwest States in subregion 6; and

• Nonattainment areas in Tennessee

receive contributions of 10 to 15 ppb

from three subregions (5, 6, and 8) with

15 to 20 ppb contributed by Midwest

States in subregion 6.

Highlights of the 8-hour contributions

from a ‘‘source’’ perspective are given

below based on the information in

Tables II–12 and II–13. The following

discussion is structured similar to that

for the 1-hour nonattainment analysis in

that results are presented for the

‘‘violating county’’ approach and

supplemented with results from the ‘‘all

grid-cell’’ approach.

Subregion 1 (portions of Illinois,

Wisconsin, Indiana, and Iowa):

emissions in this subregion contribute

over 25 ppb to nonattainment in

Michigan with contributions of 5 to 10

ppb in Ohio as well as contributions of

2 to 5 ppb to six other States.

Subregion 2 (portions of Michigan,

Indiana, and Ohio): emissions in this

subregion contribute 2 to 5 ppb to 16

States as far downwind as New

Hampshire and Maine with

contributions of 5 to 10 ppb or more in

five States.

Subregion 3 (portions of

Pennsylvania, New York and Delaware):

emissions in this subregion contribute

10 to 15 ppb to three States along the

Northeast Corridor with contributions of

5 to 10 ppb in Massachusetts and New

Hampshire.

Subregion 4 (New Jersey, Connecticut

and portions of New York, Pennsylvania

and Delaware): emissions from this

subregion contribute over 25 ppb to

Rhode Island and Massachusetts with

contributions of 15 to 20 ppb in Maine.

Subregion 5 (portions of Illinois,

Indiana, Kentucky, Missouri, and

Tennessee): emissions from this

subregion contribute 2 ppb or more to

13 States with contributions of 10 to 15

ppb in two States.

Subregion 6 (portions of Ohio,

Indiana, Kentucky, Tennessee, West

Virginia and Virginia): emissions in this

subregion contribute 5 to 10 ppb or

more to 10 States with contributions of

15 ppb or more in two States.

Subregion 7 (Maryland, Washington,

DC, and portions of Delaware, North

Carolina, Virginia and West Virginia):

emissions in this subregion contribute

10 to 15 ppb or more to four States with

contributions of 5 to 10 ppb as far

downwind as Rhode Island and

Massachusetts and 2 to 5 ppb in Maine.

Subregion 8 (portions of North

Carolina, South Carolina and Georgia):

emissions in this subregion contribute

10 to 15 ppb to three States and 15 to

20 ppb to one of these States; multiple

contributions of 2 to 5 ppb are predicted

as far downwind as New Jersey.

Subregion 9 (portions of Tennessee,

Georgia, Alabama, Mississippi, North
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60339

and South Carolina and Arkansas):

emissions in this subregion contribute 5

to 10 ppb to six States with

contributions of 10 to 15 ppb in two

States.

Subregion 10 (Florida and portions of

Mississippi, Alabama, Georgia and

Louisiana): emissions in this subregion

contribute 2 to 5 ppb in two States and

5 to 10 ppb in one State.

Subregion 11 (portions of Texas,

Louisiana, Arkansas and Oklahoma):

emissions in this subregion contribute 2

to 5 ppb in six States.

Subregion 12 (portions of Missouri,

Iowa, Wisconsin, Minnesota, North

Dakota, South Dakota, Nebraska, Kansas

and Oklahoma): emissions in this

subregion contribute 2 to 5 ppb in three

States; considering the ‘‘all grid-cell’’

approach indicates multiple

contributions of 2 to 5 ppb downwind

over Lake Michigan and Lake Erie.

The results indicate that the

contributions to 8-hour nonattainment

are very consistent with those for 1-hour

nonattainment. Subregions 1 through 9

have a much greater magnitude,

frequency, and geographic extent of

contribution compared to the other

subregions. Thus, based on this

assessment, EPA believes that emissions

from subregions 1 through 9 make a

marked contribution to downwind

nonattainment for the 8-hour NAAQS.

In fact, the extent of contributions from

most of these subregions (i.e., 1 through

9) is even larger for 8-hour

nonattainment while the contribution

from the other subregions (i.e., 10, 11,

and 12) still remains relatively low by

comparison.

8. Assessment of State Contributions

The preceding air quality, trajectory,

emissions, and modeling analyses

provide a number of pieces of

information for determining, based on

the weight of evidence, which States

make a significant contribution to

downwind nonattainment. The

assessment of the State contributions is

divided into three parts. States which

are wholly or partially contained within

subregions 1–9 are considered first since

emissions from these States make a

marked contribution to downwind

nonattainment for both the 1-hour and

8-hour NAAQS, based upon the

subregional modeling. States which

were not included in any of the OTAG

subregions (i.e., some of the New

England States) are considered second.

States located in subregions 10, 11 and

12, which did not have a marked

contribution to downwind

nonattainment for either the 1-hour or 8-

hour NAAQS, are discussed last.

The subregional modeling results

indicate that emissions from States in

subregions 1 through 9 produce large

downwind contributions in terms of the

magnitude, frequency, and geographic

extent of the downwind impacts. In

addition, nonattainment areas within

many States in the OTAG region receive

large and/or frequent contributions from

emissions in these subregions. The EPA

believes that the following States whose

emissions are wholly or partially

contained within one or more of these

subregions (i.e., Alabama, Connecticut,

Delaware, Washington DC, Georgia,

Illinois, Indiana, Kentucky, Maryland,

Michigan, Missouri, New Jersey, New

York, North Carolina, Ohio,

Pennsylvania, South Carolina,

Tennessee, Virginia, West Virginia, and

Wisconsin) is making a significant

contribution to downwind

nonattainment. In addition to the

marked levels of contributions

described above, this finding is based

on:

• OTAG strategy modeling and nonOTAG modeling indicates that NOX

emissions reductions across these States

would produce large reductions in 1-

hour and 8-hour ozone concentrations

across broad portions of the region

including 1-hour and 8-hour

nonattainment areas;

• The air quality, trajectory, and wind

vector analyses indicate that these

States are upwind from nonattainment

areas within the 1- to 2-day distance

scale of transport;

• These States form a contiguous area

of manmade emissions covering most of

the core portion of the OTAG region;

• 11 of the States that are wholly

within these nine subregions (i.e.,

Illinois, Indiana, Kentucky, New Jersey,

North Carolina, Ohio, Pennsylvania,

South Carolina, Tennessee, Virginia and

West Virginia) have a relatively high

level of NOX emissions from sources in

their States; these States are ranked in

the top 50 percent of all States in the

region in terms of total NOX emissions

and/or have NOX emissions exceeding

1000 tons per day, as indicated in Table

II–1;

• States wholly within subregions 1

through 9 with lesser emissions (i.e.,

Connecticut, Delaware, Maryland) and

Washington, DC have a relatively high

density of NOX emissions, as indicated

in Table II–2;

• For the nine States that are only

partially contained in one of subregions

1 through 9 (i.e., Arkansas, Iowa,

Michigan, Mississippi, Missouri,

Alabama, Georgia, Wisconsin, and New

York) the State total NOX emissions in

Table II–1 as well as each State’s

contribution to NOX emissions in the

subregions (see Tables II–14a and II–

14b) indicate that six of these States

(i.e., Michigan, Missouri, Alabama,

Georgia, Wisconsin, and New York)

each have: NOX emissions that are

generally more than 10 percent of the

total NOX emissions in one of these

subregions, and either NOX emissions in

the top 50 percent among all States,

and/or a majority of the State’s NOX

emissions are within one of these

subregions.

For the New England States that were

not included in any of the OTAG zeroout subregions (i.e., Maine,

Massachusetts, New Hampshire, Rhode

Island, and Vermont), State emissions

data indicate that both Massachusetts

and Rhode Island have a high density of

NOX emissions (see Table II–2). Also,

the trajectory and wind vector analyses

indicate that these States are

immediately upwind of nonattainment

areas in Maine and New Hampshire.

Thus, EPA believes that these two States

(i.e., Massachusetts and Rhode Island)

also make a significant contribution to

downwind nonattainment for both the

1-hour and 8-hour NAAQS.

In summary, based on the weight of

evidence, EPA believes that the 22

States plus the District of Columbia’s

consolidated metropolitan statistical

area which make a significant

contribution to downwind

nonattainment for both the 1-hour and

8-hour NAAQS are:

Alabama,

Connecticut,

Delaware,

District of Columbia,

Georgia,

Illinois,

Indiana,

Kentucky,

Maryland,

Massachusetts,

Michigan,

Missouri,

New Jersey,

New York,

North Carolina,

Ohio,

Pennsylvania,

Rhode Island,

South Carolina,

Tennessee,

Virginia,

West Virginia,

Wisconsin.

It should be noted that under EPA’s

alternative interpretation of section

110(a)(2)(D), these areas would be

determined to significantly contribute to

nonattainment problems downwind

only after consideration of additional

factors, including the respective costs of

controls on emissions in upwind and
60340 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

7 32 percent is the median effectiveness of the

RCS considering all nonattainment areas in the

OTAG region.

downwind areas, to the extent this

information is at least qualitatively

available. Those additional factors,

discussed in section II.D. below, leads

EPA to propose to conclude that these

areas contribute significantly under this

interpretation as well.

For the nine States in the OTAG

region which are wholly within

subregions 10, 11, and 12 (i.e., Florida,

Kansas, Louisiana, Minnesota,

Nebraska, North Dakota, Oklahoma,

South Dakota, and Texas), the OTAG

and non-OTAG modeling information

indicates that emissions from these

States make at most a relatively small

contribution to downwind

nonattainment. Also, most of these

States are relatively distant from many

of the downwind nonattainment areas

in the OTAG region and have a

relatively low amount of manmade NOX

emissions and/or NOX emissions

density. Thus, as discussed in section

VI, States Not Covered By This

Rulemaking, the weight of evidence

available does not support a finding that

these States make a significant

contribution to downwind

nonattainment.

D. Comparison of Upwind and

Downwind Contributions to

Nonattainment and Costs of Controls

Important parts of EPA’s

determination of whether, and to what

extent, to require controls on upwind

NOX emissions that are linked to

regional transport are comparing the

contribution to downwind

nonattainment problems of upwind

NOX emissions as opposed to local,

downwind NOX or VOC emissions; as

well as comparing the costs of achieving

downwind ozone reductions through

upwind emissions reductions, as

opposed to through downwind

emissions reductions. Depending on the

interpretation for section 110(a)(2)(D),

the relative downwind contribution and

the respective costs are either a factor in

the determination of what emissions

limitations constitute adequate

mitigation of that contribution, or they

are a factor in the significant

contribution test.

Under the CAA requirements,

downwind nonattainment areas are

already obligated to implement

significant controls. The provisions for

classified areas mandate cascading

control requirements so that higher

classified areas must implement the

same controls as lower classified areas,

plus additional controls. These

mandated controls generally are

assumed in the OTAG/EPA modeling

for the 2007 base case, as described

above. These mandated controls may be

viewed as the first increment of required

controls that will bring the

nonattainment areas into attainment.

Today’s proposal indicates that the next

increment of controls should be the

regional controls, for the reasons

described below.

The EPA has developed preliminary

data indicating that regional NOX

emissions reductions in the OTAG

region are a cost-effective means for

reducing ozone levels in nonattainment

areas downwind, compared to the costs

of further reductions in local VOC and

NOX emissions in those nonattainment

areas. The EPA developed this

information based on data from the

recent regulatory impact analysis (RIA)

for the new ozone standard. The EPA

estimated the amount of VOC and/or

NOX emissions reductions which would

be needed for areas to attain the new

standard as well as the air quality

improvement resulting from a regional

NOX strategy. The EPA then compared

the potential cost of achieving

attainment through a strictly local

emission reduction approach alone to

the cost of a regional NOX strategy.

The preliminary cost comparison was

based on a simplified analysis that

illustrates the potential control cost

difference between a regionallycoordinated NOX strategy and a

collection of local control strategies in

projected ozone nonattainment areas.

The analysis estimates that the existence

of a 22-States and the District of

Columbia (‘‘23 jurisdiction’’) regional

NOX strategy has the potential to avoid

from $2.9 to $12.8 billion dollars of the

total annual cost that would be incurred

under the alternative local control

strategy. This ‘‘cost avoided’’ can be

compared to the estimated annual cost

of $2.8 billion for the regional NOX

strategy assumed in the RIA to evaluate

the relative efficiency of a regional

strategy.

The EPA’s analysis is based on two

runs of the ROM. The first run, called

the local control strategy (LCS) run,

estimates ozone air quality based on a

2007 emissions projection assuming

CAA-mandated controls, but not

including a regional NOX strategy. The

second run, called the regional control

strategy (RCS) run, estimates ozone air

quality based on a 2007 emissions

projection with a regional NOX strategy.

This strategy includes a regionwide

emissions cap based on a 0.15 lb/

MMBtu NOX limit on utilities and large

industrial boilers, and the National Low

Emission Vehicle (NLEV) program.

While not identical to the regional

control assumptions in this rulemaking,

the RCS run is similar enough to offer

insights for this cost comparison.

Using the LCS ROM runs, EPA

estimated the potential local NOX and/

or VOC emission reductions needed in

17 projected ozone nonattainment areas

to attain the new 8-hour ozone standard.

An additional 13 areas are also

projected to be nonattainment under the

LCS scenario, but emission reduction

targets were not established for these

areas. These additional areas are not

included in this analysis; thus, the

estimates presented in this analysis of

the potential local control cost avoided

due to the regional NOX strategy are

likely underestimated.

Based on the ROM run for the RCS

scenario, EPA estimated the effect of the

regional NOX strategy on future ozone

concentrations for the 17 areas. Seven of

these 17 areas are projected to attain the

new ozone standard as a result of

controls in the RCS scenario. These 7

areas are given a 2007 RCS reduction

target credit of 100 percent (i.e., further

local reductions may not be needed for

attainment). For the 10 remaining

nonattainment areas, the RCS is

estimated to be 32 percent effective 7

toward achieving the air quality

attainment target relative to the LCS.

This is based on a comparison of ROM

predictions for the LCS and RCS

scenarios versus the air quality target

(0.08 ppm/8-hour/4th max ozone

standard). Therefore, all remaining areas

are given a 32 percent credit toward

their respective VOC and/or NOX

emission reduction targets. For the

regional NOX strategy, the total avoided

local VOC reductions are over 513,000

tons, and the total avoided local NOX

reductions are nearly 767,000 tons. This

analysis indicates that the regional NOX

emissions reductions provide equivalent

air quality benefits to a large portion of

the local VOC and/or NOX emissions

reductions which may be needed to

attain in these areas. This finding

weighs in favor of concluding that the

regional NOX reductions are appropriate

to mitigate the upwind contribution or,

under the second interpretation of

section 110(a)(2)(D), that the relevant

upwind areas significantly contribute to

nonattainment problems downwind.

As discussed in the next section, EPA

has identified a set of regional NOX

controls in a cost range of $1,650 to

$1,700 per ton. These regional upwind

and downwind control costs appear to

compare favorably to the potential

control costs associated with the

downwind local controls, as indicated

in Table II–15. The avoided cost of local

VOC control is assumed to range from
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60341

a low-end cost of $2,400 per ton to a

high-end cost of $10,000 per ton. The

avoided cost of local NOX control is

assumed to range from a low-end cost of

$2,200 per ton to a high-end cost of

$10,000 per ton. The low-end costs are

derived from the nationwide average

incremental costs of VOC- and NOXrelated control measures selected in the

RIA for the new ozone standard. The

high-end cost of $10,000 per ton is

assumed based on the Presidential

Directive for the Administrator of EPA

regarding ‘‘Implementation of Revised

Air Quality Standards for Ozone and

Particulate Matter’’ issued by President

Clinton.

The foregoing analysis suggests, at

least directionally, that the regional

NOX reductions that would result from

today’s proposal may have the same

ambient impact, but at lower cost, than

available local VOC and NOX

reductions. Thus, this analysis is

another factor supporting EPA’s

proposed conclusion that the SIPs for

States in this region are required, under

section 110(a)(2)(D), to reduce NOX

emissions.

III. Statewide Emissions Budgets

A. General Approach for Calculating

Budgets

This section describes the general

approach EPA is proposing to use to

develop emission budgets under today’s

action and the rationale for that

approach. In addition to a description of

how control measures were selected,

this section addresses other issues

related to calculating budgets,

including: relationship to OTAG

recommendations, uniform application

of controls, seasonal versus annual

controls, and treatment of areas with

NOX waivers.

1. Overview

In earlier parts of today’s action, EPA

proposed to determine that NOX

emissions from 23 jurisdictions

contribute significantly to

nonattainment problems in downwind

areas in the OTAG region. In this and

subsequent parts, EPA proposes to

require a NOX budget for each of these

jurisdictions for those emissions that

will result in sufficient reductions to

adequately mitigate the contribution.

The EPA proposes as the criteria for

establishing the budget the relative cost

effectiveness of the emissions

reductions associated with the available

controls, combined with reference to the

ambient impact of the emissions

reductions. The EPA solicits comment

on alternative approaches for

establishing State emissions budgets

that factor in the differential effects of

NOX reductions in different geographic

locations on downwind air quality.

Specifically, for the proposed

approach, EPA employed the following

steps in determining the budget levels

that EPA proposes constitute adequate

mitigation under the first interpretation

of significant contribution. First, EPA

compiled a list of available NOX control

measures for the various emissions

sectors in the upwind areas. For the

control measures on this list, EPA

estimated the average cost effectiveness

of those controls. The average cost

effectiveness is defined as the cost of a

ton of reductions from the source

category based on full implementation

of the proposed controls, as compared to

the pre-existing level of controls.

Second, EPA developed a rationale for

determining which of the NOX control

measures should form the basis of the

budget. The EPA focused on average

cost effectiveness of the controls. As a

point of comparison, EPA determined

the average cost effectiveness of a

representative sample of recent current

and planned State and Federal controls.

The EPA believes that the average cost

effectiveness for the measures proposed

today to form the basis for the budgets

should be comparable to the average

cost effectiveness of those recently

undertaken and planned controls.

Third, EPA evaluated control

measures to determine whether they

should be assumed in the budget

calculation based on this rationale. The

EPA proposes that when controls on

utilities in the 23 jurisdictions are

extended to the level proposed today,

and when controls on nonutility point

sources are similarly extended, then the

average cost effectiveness of the utility

controls and of the nonutility point

source controls are both comparable to

the average cost effectiveness of recently

undertaken and planned controls.

At the same time, EPA analyzed the

average cost effectiveness for NOX

reductions from source categories other

than utilities or other point sources. The

EPA is today proposing that additional

controls (beyond the current and

planned measures described in section

III.B.2.b) from those categories should

not form the basis for any of the budgets

because their costs, for the purpose of

reducing only NOX emissions, are

significantly higher than those of the

utilities and other point sources and/or

additional feasible controls have either

not been identified or are more

appropriate for local, not regional,

implementation.

Fourth, EPA determined the state-bystate budgets for NOX emissions based

on the selected controls.

Fifth, EPA determined that these

budget levels—or generally comparable

levels—result in an adequate level of

ambient reductions downwind. The

EPA did not conduct ambient air quality

modeling for the level of emissions

contained in the budgets proposed

today. However, OTAG conducted air

quality modeling for a set of controls

that, although somewhat different from

the utility and point source controls

EPA is today proposing to rely on,

yielded comparable emission levels, on

a regionwide basis, to those proposed

today. This modeling indicated a

noticeable improvement in ozone

concentrations due to implementation

of the required emissions budget. The

Agency intends to include air quality

analyses of the proposed NOX emissions

budgets in the SNPR. Although EPA is

proposing that States be required to

achieve the emissions budgets specified

and has based those budgets on a

particular set of cost-effective controls,

States may select their own mix of

controls that meet this budget.

Sixth, EPA determined that, based on

current information, requiring upwind

NOX emissions reductions, based on an

assessment of their costs and ambient

impact, is more appropriate than

requiring downwind VOC emissions

reductions, based on an assessment of

their costs and ambient impacts. The

EPA’s current information is limited for

this aspect of today’s rulemaking, but

generally consists of the analyses

performed for the RIA for the revised

ozone and particulate matter NAAQS.

The alternative interpretation for

section 110(a)(2)(D) of the CAA, which

EPA is also proposing today, should

also be noted. Under this interpretation,

the various factors included in the

weight of evidence approach discussed

above concerning the upwind emissions

and ambient contributions, therefore,

would be part of the determination as to

whether the emissions contribute

significantly to nonattainment problems

(or interfere with maintenance

downwind). The EPA would then

undertake the same cost analysis as

described above as an additional factor

in the weight of evidence test. If EPA

concluded that the regional NOX

emissions controls are appropriately

cost effective, EPA would conclude, on

the basis of all the factors, that the

emissions subject to those controls are

considered to contribute significantly to

nonattainment. Under this

interpretation of section 110(a)(2)(D),

the State budget levels, which are based

on the cost-effective control measures,

are necessary to prohibit the amount of

the State’s emissions determined to
60342 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

contribute significantly to

nonattainment.

2. Relationship of Proposed Budget

Approach to the OTAG

Recommendations

In selecting those control measures

determined to be the most reasonable

and cost effective for the purpose of

achieving regional NOX reductions, EPA

carefully considered the

recommendations made by OTAG on

July 8, 1997 (Appendix B). The OTAG

process is described in section I.F,

OTAG Process, of this rulemaking. The

control measures assumed in the

proposed budget calculations described

below generally fall within the range of

OTAG’s recommendations.

The OTAG recommendations call for

implementation of several Federal

measures to achieve NOX emissions

decreases through a NLEV program,

inspection and maintenance (I/M)

programs (where required by the CAA),

and reformulated gasoline (RFG) in

mandated and current opt-in areas.

Emissions reductions following these

recommendations are included in EPA’s

calculation of the highway vehicle

budget component as part of the 2007

Clean Air Act base.

The OTAG recommendations endorse

the development and implementation of

ozone action-day programs. The

recommendations also encourage EPA

to evaluate emission benefits of cetane

adjustments with respect to diesel fuel.

While EPA supports these

recommendations, it should be noted

that they do not translate into specific

emissions reductions at this time and,

thus, EPA did not calculate emissions

reductions from these programs as part

of the proposed budget calculation.

The OTAG recommendations also

cover electric utilities and other largeand medium-sized point sources.

Specifically, OTAG recommended

controls discussed below in all of the

‘‘fine grid’’ areas. The OTAG

recommended that emissions from

sources in the portion of States that are

in the ‘‘coarse grid’’ be exempted from

the budget calculation. The EPA is

proposing to include entire States rather

than exempting portions based on the

division between coarse and fine grid.

This affects New York, Michigan,

Wisconsin, Missouri, Alabama and

Georgia. The EPA proposes to take this

approach because the division between

fine and coarse grid areas was based, in

part, on technical modeling limitations;

because the additional emissions

decreases will help the downwind

nonattainment areas; and because a

statewide budget creates fewer

administrative difficulties than a partialstate budget. The OTAG fine grid States

are the same as the 23 jurisdictions

proposed in this rulemaking as having

a significant contribution, with the

exception of the States of Maine, New

Hampshire and Vermont. The portion of

these three States in the OTAG fine grid

are included in the OTAG

recommendation for additional controls,

but are not included in today’s proposal

for the reasons described in section II,

Weight of Evidence Determination of

Significant Contribution, of this

rulemaking. The EPA is soliciting

comments on this approach;

specifically, whether partial States

should be included, which States or

parts of States should be excluded, the

appropriate rationale for excluding

States or parts of States, and how to

address administrative difficulties

associated with excluding parts of a

State.

For electric utilities, OTAG

recommended that the range of utility

NOX controls in the fine grid fall

between CAA controls (about a 30

percent reduction from 1990 levels) and

the less stringent of 85 percent

reduction from the 1990 rate or 0.15 lb/

MMBtu. As discussed below, EPA’s

proposed utility budget component

calculation is based on the 0.15 lb/

MMBtu emission rate without the 85

percent reduction option. Thus, EPA’s

proposed utility budget component

calculation is similar to the upper

bound recommended by OTAG, but

with a slightly lower overall emission

rate (since it excludes the 85 percent

reduction criterion) and slightly

different total area (since whole States—

not just the fine grid portion—but fewer

States are included). The alternatives

considered and explanation of the

methodology proposed to make these

calculations are more fully discussed

below and in the technical support

document (TSD) which is included in

the Docket to this rulemaking.

For nonutility point sources, OTAG

recommended that the stringency of

controls for large sources be established

in a manner equitable with utility

controls. The OTAG recommendation

includes a definition of large sources

(e.g., industrial boilers with a heat input

greater than 250 MMBtu) and

recommends control levels ranging from

55–70 percent reduction. The OTAG

Policy Group further recommended that

RACT should be considered for

individual medium-sized nonutility

point sources (e.g., industrial boilers

with a heat input between 100 and 250

MMBtu). The EPA-proposed nonutility

budget component calculations

generally follow the OTAG

recommendations. Missing data in the

OTAG emissions inventories, however,

preclude EPA from precisely following

the recommended definitions of largeand medium-sized sources. The

alternatives considered and explanation

of the methodology proposed to make

these calculations are more fully

discussed below.

3. Uniform Application of Control

Measures

The EPA is proposing that the budget

for each State that has been determined

to contribute significantly to

nonattainment in a downwind State be

calculated using the same control

measure assumptions. This is true under

either interpretation, described above, of

section 110(a)(2)(D). An alternative

approach would be for EPA to attempt

to identify for each State or a group of

adjacent States (e.g., Ohio Valley, Great

Lakes, Southern, or Northeastern States)

a unique set of control levels on which

to base emissions budgets that, together

with other States’ emission budgets,

would eliminate significant contribution

to downwind nonattainment areas. The

EPA is soliciting comment on

methodologies that might be used to

implement such an approach. The

decision to propose to calculate budgets

based on uniform control measures is

based primarily on cost effectiveness

(cost per ton removed) and also in

consideration of the OTAG

recommendations, collective

contribution, equity concerns, modeling

assumptions and concerns over

emissions shifting. These are discussed

further below.

a. OTAG. Although OTAG did note

that the range of transport is generally

longer in the North than in the South,

the OTAG recommendations did not

specifically indicate whether controls

should be applied at differing levels

over the fine grid.

b. Collective Contribution and Equity

Considerations. The EPA believes that

certain downwind States receive

amounts of transported ozone and ozone

precursors that significantly contribute

to their nonattainment. The EPA further

believes that it is the ‘‘collective’’

emissions of ‘‘several’’ upwind States

that result in significant contributions.

All States included within a group of

States whose collective emissions

significantly contribute to

nonattainment may be assumed to

contribute significantly. Because each

State’s contribution is viewed with

reference to other States’ contributions,

EPA believes it is appropriate to require

the same type of remedial action for

each State.

The proposed approach results in the

calculation of statewide emissions
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60343

budgets based on the consistent

application of potential controls across

the States determined to contribute

significantly. This approach treats the

23 jurisdictions in a like manner for the

purpose of calculating the proposed

statewide emissions budgets.

c. Modeling Assumptions and

Potential Synergistic Effects. In theory,

it would be possible to derive more

precise contributions made by

individual States to collective transport

of ozone and precursors to downwind

States. In practice, however, this is a

more challenging analysis. First, the

relative impact of individual States,

within a collective group of States, on

transport varies as a function of

meteorology. For example, the impact of

more distant States may be relatively

greater when there is a well defined

windfield. In contrast, effects of nearby

States may be most pronounced under

stagnant or semi-stagnant conditions.

Modeling may therefore not sufficiently

characterize the relative importance of

emissions in individual States to

regional transport, unless many days

reflecting a variety of meteorological

conditions are modeled.

Second, the impact of an individual

State on downwind transport of ozone

and precursors depends on what is

assumed about emissions in other States

in the collective group shown to result

in significant transport. This is

exacerbated by the fact that ozone

formation and transport is not a linear

function of precursor emissions. Rather,

there is likely to be a synergistic effect

which arises from reducing emissions in

several neighboring States. Thus, the

predicted relative importance of

emissions from a single State might

change substantially if emissions from

other States in the group were reduced.

There is a myriad of assumptions which

can be made about emission controls in

neighboring States. It is not feasible to

model them all. Thus, a definitive,

precise estimate of the relative

importance of a single State’s

contribution to transport is unlikely. On

the other hand, OTAG has performed

modeling showing the air quality

impacts of applying differential levels of

controls in different zones of the OTAG

domain (see section II.B.3, OTAG

Geographic Modeling). In section

III.A.3.e below, EPA is requesting

comment on the possibility of using this

or some other analysis as a means for

considering an alternative approach to

developing NOX budgets.

d. Electrical Generation and

Emissions Shifting. Among many factors

that EPA considered in weighing

whether to propose uniform or variable

emissions limits in calculating States’

emission budgets was the concern that

different controls in one part of the

OTAG fine grid region in combination

with an interstate emissions trading

program may lead to increases in

pollution within areas having more

restrictive controls. That is, if

unrestricted interstate emissions trading

were allowed, emissions reductions

might be expected to shift away from

States assigned more restrictive controls

to States which received less restrictive

control requirements due to the lower

control costs likely to exist in States

with less restrictive controls. This may

result in emissions above the budget

level in areas with more restrictive

controls. Such shifts are an important

concern and may be most significant for

large combustion sources because they

emit a large portion of the total regional

NOX emissions and dominate point

source emissions.

On the other hand, having the

interstate trading program incorporate

control levels that vary from State to

State by varying the value of an

emission credit or allowance would

complicate administration of the trading

program. Such complexity would

increase transaction costs and could

discourage emissions trading which

may result in higher regionwide control

costs. Alternatively, the scope of the

trading program could be confined to

those States with similar control levels.

However, each subregional trading

program would have fewer participants.

A trading program that covers a smaller

market area will provide less flexibility

and reduce the possible savings for the

affected sources as compared with larger

trading programs.

e. Alternative Approaches Based on

Non-Uniform Application of Control

Measures. The EPA is proposing to

derive State NOX emissions budgets

using uniform control measures. As

discussed earlier in this section, EPA

believes it is appropriate to require

comparable levels of control of NOX

emissions throughout the 23

jurisdictions covered by today’s action.

The EPA selected these proposed levels

primarily by considering the cost

effectiveness of control at the source

(i.e., the control cost per ton of NOX

reduced for each type of source).

Although not all such emissions

reductions are equally effective in

reducing ozone concentrations in target

nonattainment areas, EPA believes that

other benefits of NOX reductions and

equity considerations are also important

and support this type of approach.

In a July 1997 Memorandum to the

EPA Administrator, the President

directed the Agency to maximize

common sense, flexibility, and cost

effectiveness in implementing the

revised ozone and particulate matter

standards. Fulfilling this mandate by

developing the least burdensome

strategy for achieving air quality

improvements, and ultimately

attainment in nonattainment areas,

requires technically complex analysis of

regional transport, similar to that

undertaken as part of the OTAG process.

As noted elsewhere in this package, a

number of other factors, including

distance and meteorology, influence

how effective different tons of emissions

reductions are in reducing ambient

ozone concentrations in nonattainment

areas.

The EPA recognizes that analytic

approaches other than one based on

using uniform control measures might

be useful in deriving State NOX

emissions budgets. For example, one

approach would be to attempt to

quantify more explicitly the cost

effectiveness in terms of the ambient

ozone improvement in nonattainment

areas (measured, for example, as cost

per population weighted changes in

parts per billion of peak ozone

concentrations) taking into account the

location of control measures through

regional modeling. This alternative, if

feasible, would clarify the linkage

between the budget calculation and

ambient ozone improvement in

nonattainment areas and, depending on

its effect on interstate emissions trading,

could thereby lower the overall cost of

achieving comparable ambient ozone

improvements in nonattainment areas.

Alternative approaches to measuring

cost effectiveness that would more

directly link cost effectiveness to

improvements of air quality in

nonattainment areas could also be

adopted.

The EPA solicits comment on

alternative approaches for establishing

State emissions budgets that factor in

the differential effects of NOX

reductions in different geographic

locations on downwind air quality.

Comments advocating alternative

approaches would be most helpful if

they set forth concrete proposals on

what analysis should form the basis for

budget calculations. The EPA plans to

review alternative approaches and

perform additional air quality and

economic analysis in developing the

final rule. If, after review of alternative

approaches, EPA concludes that a new

basis for the State emissions budgets is

appropriate, EPA would issue a SNPR.

4. Seasonal vs Annual Controls

Today’s proposal is for the purpose of

helping attain and maintain the NAAQS

for ozone. High ambient concentrations
60344 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

of ozone are associated with periods of

elevated temperature and solar

radiation. Thus, in most parts of the

country, high ozone episodes occur only

during summer months. Accordingly,

the control of NOX emissions primarily

on a summer season basis may be part

of some areas’ strategies to attain the

ozone standard at least cost. The OTAG

analyses have assumed that the control

requirements flowing from this process

would be required only over the ozone

season, which OTAG considered to be

May 1 through September 30. For the

purpose of decreasing the regional

transport of ozone and ozone

precursors, EPA agrees that control

measures that focus over the ozone

season may be appropriate and is

proposing seasonal NOX budgets.

Because NOX emissions have adverse

impacts on the environment in several

ways (as described in section IX.,

Nonozone Benefits of NOX Reductions),

it should be noted that the timing of the

NOX emissions can be important to the

subsequent environmental impacts. For

example, year-round reductions in NOX

emissions are more helpful than

seasonal approaches at minimizing the

impacts of acid deposition and

eutrophication, although summertime

NOX emissions reductions are most

helpful in attaining the ozone standard.

Application of NOX emissions controls

that focus emissions reductions in the

summer will, in many cases, also

achieve significant emission reductions

on a year-round basis. For example,

efforts to decrease emissions from large

boilers will usually include installation

of low NOX burners—which will

achieve year-round moderate amounts

of emission reductions—and may

include, in addition, some type of

summer season control, such as

switching to a cleaner fuel or postcombustion technology. Therefore,

while the purpose of this rulemaking is

to address ozone transport that

significantly contributes to downwind

nonattainment, which is primarily a

concern during the ozone season, States

may wish to consider the total

environmental impacts when adopting

measures to achieve the NOX emissions

decreases.

The OTAG modeling used emissions

inventory information that represented

typical summer day emissions. In this

rulemaking, EPA is proposing seasonal

emission budgets for each of the 23

affected jurisdictions. Thus, in

developing the budget, a conversion is

needed to arrive at a seasonal budget. As

in the OTAG process, EPA is proposing

to use May 1 through September 30 as

the ozone season. The detailed

procedures for converting the daily

emissions into the seasonal budgets are

described below for each source sector.

The proposed budgets are in units of

tons of anthropogenic NOX for the

season May 1 to September 30. Since

States will generally only be able to

affect anthropogenic sources, the

proposed budget does not include

biogenic or geogenic sources.

5. Consideration of Areas With CAA

Section 182(f) NOX Waivers

The OTAG process included lengthy

discussions on the potential increase in

local ozone concentrations in some

urban areas that might be associated

with a decrease in local NOX emissions.

The OTAG modeling results indicate

that urban NOX emissions decreases

produce increases in ozone

concentrations locally, but the

magnitude, time, and location of these

increases generally do not cause or

contribute to high ozone concentrations.

That is, NOX reductions can produce

localized, transient increases in ozone

(mostly due to low-level, urban NOX

reductions) in some areas on some days,

but most increases occur on days and in

areas where ozone is low. The OTAG

recommended that the States work

together and with EPA toward

completing local SIPs, including

evaluation of possible local NOX

disbenefits. The EPA agrees that further

analysis of this effect is needed as part

of the development of local attainment

plans. With respect to regional ozone

transport and today’s proposed action,

EPA believes it is not appropriate to

give special treatment to areas with NOX

waivers as discussed below.

In calculating the proposed statewide

NOX emissions budget, EPA considered

the options of: (1) requiring less

reductions from a State that had been

granted a NOX waiver under section

182(f) of the CAA, or (2) ignoring the

NOX waiver for purposes of calculating

the transport budget. As described

below, EPA believes it is inappropriate

to give special treatment to areas with

NOX waivers when considering

measures to reduce the regional

transport of ozone and ozone

precursors. Therefore, EPA is proposing

to calculate the statewide emissions

budget without special consideration for

areas with NOX waivers. The EPA views

the effect of NOX waivers on air quality

as appropriate for further analysis by

each State as part of its local attainment

planning process, and EPA will

consider such results when working

with each State’s attainment plan.

In option (1), the upwind States with

NOX waivers would achieve only a

portion of the emissions decreases

otherwise required under the statewide

emissions budget. Thus, the downwind

nonattainment areas would receive less

improvement in air quality and would

need to adopt additional control

measures in their States. To some degree

this approach defeats the purpose of

today’s action because fewer emissions

reductions in the upwind areas would

lead to higher ozone concentrations in

the downwind areas.

In option (2), the upwind States may

be able to achieve the NOX emissions

decreases needed to meet their budgets

in those portions of the State where

NOX emissions decreases are not a

problem. On the other hand, the State

may need to implement some NOX

emissions decreases in areas where such

decreases may lead to increases in

ozone concentrations on some days.

Thus, additional VOC control measures

may be needed to offset associated

ozone increases due to NOX emissions

decreases in the sensitive areas. This

approach is more consistent with the

purpose of today’s action and may or

may not result in additional VOC

controls being needed.

In proposing option (2), it is helpful

to look more closely at why the NOX

waivers were initially granted and the

manner in which they were granted.

Most of the NOX waivers granted were

not supported by local or regional scale

air quality modeling analyses indicating

that NOX emissions decreases would

result in ozone increases. In fact, most

of the waivers were granted based solely

on local air quality data indicating the

areas were already attaining the ozone

standard. Thus, technical support for

option (1) is substantially incomplete. In

addition, relevant modeling analyses

completed by OTAG and others

regarding the issue of NOX waiver areas

need to be considered as described

below.

The CAA requires EPA to view NOX

waivers in a narrow manner. In general,

section 182(f) provides that waivers

must be granted if states show that

reducing NOX within a nonattainment

area would not contribute to attainment

of the ozone NAAQS within the same

nonattainment area. Only the role of

local NOX emissions on local attainment

of the ozone standard is considered in

nonattainment areas outside an ozone

transport region. The role of NOX in

regional attainment is addressed

separately under section 110(a)(2)(D) of

the Act, which prohibits one State from

significantly polluting another State’s

downwind areas.

In response to State NOX waiver

petitions submitted between 1992–1995,

EPA granted NOX waivers under section

182. Most waivers were granted on the

basis that the area had already attained
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60345

the ozone standard and, thus, additional

NOX (or VOC) reductions ‘‘would not

contribute to ozone attainment in the

area.’’ In some cases, the waivers were

granted based on dispersion modeling

which showed that the area would

attain just as expeditiously based solely

on additional VOC reductions or that

local NOX reductions increased local

peak ozone concentrations; this also

meets the above test that additional NOX

reductions would not contribute to

ozone attainment in the area.

Specifically, the EPA received

petitions for a NOX waiver for 51 ozone

nonattainment areas. Of these petitions,

EPA has approved waivers for 48

nonattainment areas and 3 are pending.

Most of the waivers granted (28 of 48)

were simply based on air quality

monitoring data over a period of 3 or

more years indicating the area had

attained the ozone standard (and, thus,

additional NOX reductions were not

needed for attainment). Several States

submitted NOX waiver petitions (7 of

48) accompanied by an attainment plan

showing achievement of the ozone

standard by the statutory deadline

through additional VOC controls only.

None of these 35 nonattainment areas

with approved NOX waivers have

demonstrated or even sought to

demonstrate that NOX reductions might

increase ozone concentrations in

specific areas. Only in the cases of the

Lake Michigan (9 nonattainment areas),

Phoenix AZ, Baton Rouge LA and the

Houston/Beaumont TX areas was

information submitted to show that, in

some episodes, NOX emissions

decreases lead to increases in peak

ozone concentrations (13 of 48). Thus,

the technical support for option (1) is

substantially incomplete. Even for the

few areas which had modeling

information, those analyses were

generally considered preliminary

analyses that would be replaced with

more complete modeling associated

with attainment plans.

In the Federal Register notices

approving individual waiver petitions,

EPA gave notice that approval of the

local petition, under section 182(f) of

the CAA, is on a contingent or

temporary basis because subsequent

modeling or monitoring data for an area

may show attainment benefits from NOX

reductions, and stated that additional

local and regional NOX emissions

reductions may be needed to reduce the

long range transport of ozone. Where

such additional NOX reductions are

necessary to reduce the long range

transport of ozone, EPA stated that

authority provided under section

110(a)(2)(D) of the CAA would be used

and that a section 182(f) NOX waiver

would, in effect, be superseded for those

control requirements needed to meet the

section 110(a)(2)(D) action. Further, EPA

noted that States may require additional

NOX reductions in these nonattainment

areas for nonozone purposes, such as

attainment of the PM–10 standard or

achieving acid rain reduction goals.

The OTAG addressed the complex

issue of regional impacts due to

transport of NOX and VOC emissions.

The OTAG modeling results indicate

that urban NOX reductions produce

widespread decreases in ozone

concentrations on high ozone days. In

addition, urban NOX reductions also

produce limited increases in ozone

concentrations locally, but the

magnitude, time, and location of these

increases generally do not cause or

contribute to high ozone concentrations.

Most urban ozone increases modeled in

OTAG occur in areas already below the

ozone standard and, thus, in most cases,

urban ozone increases resulting from

NOX reductions do not cause

exceedance of the ozone standard. There

are a few days in a few urban areas

where NOX reductions are predicted to

produce ozone increases in portions of

an urban area with high ozone

concentrations.

In other words, modeling analyses

conducted as part of the OTAG process

indicated that, in general, NOX

reduction disbenefits are inversely

related to ozone concentration. On the

low ozone days leading up to an ozone

episode (and sometimes the last day or

so), the increases are greatest, and on

the high ozone days, the increases are

least (or nonexistent); the ozone

increases occur on days when ozone is

low and the ozone decreases occur on

days when ozone is high. This indicates

that, in most cases, urban ozone

increases may not contribute to

exceedances of the ozone standards.

Overall, OTAG modeling thus suggests

that the ozone reduction benefits of NOX

control may outweigh the disbenefits of

urban ozone increases in both

magnitude of ozone reduction and

geographic scope.

It should be noted that the modeling

analyses completed within the OTAG

process necessarily utilized a larger grid

size than States are likely to use in their

attainment plans. That is, future

analyses by States will likely use

smaller grid sizes. The smaller grid sizes

may provide additional information on

effects such as local NOX emissions

reacting with local ozone. The

additional information will be

important as States develop their

attainment plans.

In summary, the EPA views ozone

pollution as a regional problem as well

as a local problem. Thus, achieving

ozone attainment for an area, and

thereby protecting its citizens from

ozone-related health effects, often

depends on the ozone and precursor

emission levels of upwind areas. In

order to achieve the needed upwind

NOX emissions decreases, areas that

were granted NOX waivers may need to

control NOX emissions for transport

purposes, even if the waivers remain in

place. Today’s action is part of the

process that is leading to additional

NOX reductions requirements in

attainment and nonattainment areas

across broad parts of the Nation to

reduce interstate transport of ozone. The

requirements of today’s action apply

both to areas with approved NOX waiver

petitions and areas without such

petitions. That is, any nonattainment

areas with NOX waiver petitions

approved by EPA in the past or in the

future are not proposed to be exempt

from today’s action.

At the same time, EPA is sensitive to

the concerns of those areas (primarily in

the Lake Michigan area) that may be

required to achieve NOX reductions that

produce local increases in ozone

concentrations in order to reduce

concentrations in downwind areas. The

EPA is, thus, taking comments on

approaches that might be used to

address such concerns on a case-by-case

basis. The EPA wishes to stress that it

would only consider an approach that

targets areas with concrete modeling

results documenting a likelihood of

local disbenefits from NOX reductions at

locations and on days with high ozone

concentrations. As already discussed,

EPA does not believe adjustments to

NOX budgets are appropriate for areas

with waivers based solely on their

ability to attain the NAAQS without

further reductions.

6. Relation of OTC NOX MOU to

Budgets in the Ozone Transport SIP

Rulemaking

The 2007 Budgets for the electric

utilities and the nonutilities were

developed independently of the OTC

NOX MOU. The Ozone Transport SIP

Rulemaking allows States flexibility to

achieve reductions from any source

category; however, implementation of

these requirements could be

coordinated. The MOU covers large

boilers, both utility and nonutility

boilers. The Ozone Transport SIP

Rulemaking covers these sources as well

as other categories of major NOX

stationary sources. Although the OTC

NOX MOU does not cover these other

categories, the OTC States regulated

emissions from these categories through
60346 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

implementation of the RACT program,

beginning in 1995.

The EPA believes that

implementation of Phase II of the MOU

should proceed as scheduled, with

achievement of the reductions by May

1999. These emissions reductions are

needed to help reduce ozone transport

and make progress toward attainment.

Further, these reductions do not conflict

with the requirements imposed by the

Ozone Transport SIP Rulemaking

because they do not exceed the required

reductions. In Phase III of the MOU,

however, the timing and the amount of

the reductions required by the OTC’s

MOU and RACT provisions are much

closer to the timing and reductions from

the Ozone Transport SIP Rulemaking.

The emissions reductions required by

the Ozone Transport SIP Rulemaking

are likely to be somewhat more stringent

overall than the OTC’s Phase III

requirements, and Phase III

implementation could occur about the

same time as the Ozone Transport SIP

Rulemaking reductions. Therefore, EPA

intends to work with the OTC States to

coordinate Phase III implementation

with implementation of the emissions

reductions required by the Ozone

Transport SIP Rulemaking.

The States in the OTC not covered by

the Ozone Transport SIP Rulemaking

should continue to develop, adopt and

implement Phases II and III of the MOU.

Such reductions may be necessary to

provide for attainment of the ozone

NAAQS in those areas, although they

may not be significant with respect to

long distance transport. Further, such

reductions may help to attain and/or

maintain the new 8-hour ozone

standard.

B. Budget Development Process

1. Overview

The EPA is proposing to develop

seasonal budgets for each State by

determining the amount of emissions

that would remain in each State after

application of reasonable, cost-effective

control measures. For all sectors except

electric utilities and nonutility point

sources, EPA proposes using the 2007

Clean Air Act inventory developed by

OTAG as the starting point for this

calculation. This inventory reflects

implementation of all mandatory

national and nonattainment area Clean

Air Act controls, plus any additional

regional and State-specific controls. It

also includes growth assumptions

between 1990 and 2007. The specific

assumptions on which this inventory is

based are documented in a June 1997

draft Emissions Inventory Development

Report (8). To determine the overall

State budgets, EPA proposes applying

controls to various source sectors, as

discussed below, calculating budget

components based on these controls,

and summing the budget components

for each sector to get the total budget.

In the case of electric utilities, EPA

proposes using a slightly different

approach. Instead of using the OTAG

2007 emissions and applying controls,

EPA proposes to calculate the utility

component of the budget using data

provided by utilities to EPA for 1995

and 1996 and increasing the emissions

to reflect activity growth projected for

2007. This is discussed in more detail

below in section III.B.3.

In the case of nonutility point sources,

EPA proposes using the OTAG 2007

emissions with one adjustment. The

inventory needs to be adjusted to

represent uncontrolled levels, rather

than CAA control levels, because the

OTAG recommendation is based on

uncontrolled levels. This is discussed in

section III.B.4, Proposed Assumptions

for Area and Nonutility Point Sources.

2. Description of and Rationale for

Proposed Control Assumptions

An important issue to be addressed in

today’s action is the reasonableness of

the cost of control of emissions in States

that significantly contribute to another

State’s ozone nonattainment. The EPA

proposes to address this issue by

examining the cost effectiveness of

various regionwide ozone season

control measures and determining what

measures can be considered the most

reasonable in light of other actions taken

by EPA and States to control NOX.

a. Considering the Cost Effectiveness

of Other Actions. The EPA is proposing

to base the budget component levels on

NOX emissions controls that are

available and the most cost effective in

relation to other recently undertaken or

planned NOX measures. Table III–1

provides a reference list of measures

that EPA and States have undertaken to

reduce NOX and their average annual

costs per ton of NOX reduced. Most of

these measures fall in the $1,000 to

$2,000 per ton range. With few

exceptions, the average cost

effectiveness of these measures is

representative of the average cost

effectiveness of the types of controls

EPA and States have needed to adopt

most recently, since their previous

planning efforts have already taken

advantage of opportunities for even

cheaper controls. The measures listed in

Table III–1 represent costs that the

Nation has been willing to bear to date

to reduce NOX. The EPA believes that

the cost effectiveness of measures that it

or States have adopted, or proposed to

adopt, forms a good reference point for

determining which of the available

additional NOX control measures can

most reasonably be implemented by

upwind States that significantly

contribute to nonattainment.

TABLE III–1.—AVERAGE COST EFFECTIVENESS OF NOX Control Measures Recently Undertaken

[In 1990 dollars]

Control measure

Cost per ton

of NOX removed

NOX RACT ................................ 150–1,300

Phase II Reformulated Gasoline 1 3,400

State Implementation of the

Ozone Transport Commission Memorandum of Understanding ................................. 950–1,600

Proposed New Source Performance Standards for Fossil

Steam Electric Generation

Units ...................................... 1,290

Proposed New Source Performance Standards for Industrial

Boilers ................................... 1,790

1Average cost representing the midpoint of

$1,500 to $5,300 per ton. This cost represents

the projected additional cost of complying with

the Phase II RFG NOX standards, beyond the

cost of complying with the other standards for

Phase II RFG.

The Federal Phase II RFG costs

presented in Table III–1 are not strictly

comparable to the other costs cited in

the table. Federal Phase II RFG will

provide large VOC reductions in

addition to NOX reductions. Federal

RFG is required in nine cities with the

Nation’s worst ozone nonattainment

problems; other nonattainment areas

have chosen to opt into the program as

part of their attainment strategy. The

mandated areas and those areas in the

OTAG region that have chosen to opt

into the program are areas where

significant local reductions in ozone

precursors are needed; such areas may

value RFG’s NOX and VOC reductions

differently for their local ozone benefits

than they would value NOX reductions

from RFG or other programs for ozone

transport benefits.

The EPA notes that there are also a

number of less expensive measures

recently undertaken by the Agency to

reduce NOX emission levels that do not

appear in Table III–1. These actions

include: (1) The Title IV NOX reduction

program, (2) the Federal locomotive

standards, (3) the 1997 proposed

Federal nonroad diesel engine

standards, (4) the Federal heavy duty

highway engine 2g/bhp-hour standards,

and (5) the Federal marine engine

standards. These lower cost actions do

not represent a useful measure of the
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60347

8However, in the Regulatory Analysis of this

action, EPA evaluates the economic impact of

including the MOU in the baseline for the electric

power industry.

9All estimates of I/M program cost effectiveness

in this rulemaking are presented in terms of the cost

per annualized summer ton of ozone precursor, i.e.,

the cost per ton of VOC or NOX. Cost per

annualized summer ton is calculated as the total

cost of the program divided by the number of tons

that would be reduced annually if the level of

reduction achieved during the summer were

achieved year round. It thus understates the cost

per actual ton of reduction of ozone precursors. The

EPA believes this procedure is appropriate because

I/M programs reduce other pollutants beside ozone

precursors (e.g., air toxics and carbon monoxide

(CO)).

willingness to make reasonable

expenditures to reduce NOX emissions

in order to achieve air quality goals.

Decisions to undertake these measures

are low cost steps toward NOX

reduction. Though these actions are

very cost effective, the Agency must

now focus on what other measures exist,

at a potentially higher cost-effectiveness

value, that can further reduce NOX

emissions. The Agency is focusing on

these other actions because they may

also be of reasonable cost effectiveness

and obtaining these reductions are less

costly than further local reductions of

VOC and NOX in nonattainment areas.

Table III–1 is thereby useful as a

reference of the next higher level of NOX

reduction cost effectiveness that the

Agency considers reasonable to

undertake.

The Agency is also aware that to come

into attainment with the new ozone

NAAQS, many localities will spend

several thousand dollars per ton of NOX

or VOC reduction.

b. Determining the Cost Effectiveness

of NOX Controls. In an effort to consider

a cost-effective mix of controls on which

to base each component of the proposed

budget (i.e., electricity generating

sources, nonutility point sources, area

sources, and mobile sources) the Agency

considered the average cost

effectiveness of alternative levels of

controls for each source. Among the

plausible levels of control are the

controls included in OTAG’s

recommendations.

The average cost effectiveness of the

controls assumed in calculating each

sector’s budget component was

calculated from a baseline level that

included all currently applicable

Federal or State NOX control measures.

The baseline did not include Phase 2

and Phase 3 of the OTC NOX MOU since

they have not yet been adopted by all

the involved States 8; if the MOU were

included in the baseline, the overall

costs would be lower. The costs and

emissions reductions for point sources

are determined using an emissions capand-trade approach since EPA believes

that this approach is the most costeffective way for point sources to meet

an emissions budget, and EPA expects

that States are also interested in

employing the most cost-effective

approach. Table III–2 shows in the first

column of numbers the average cost per

ton of NOX removed during the ozone

season of various potential EPA actions,

arranged by source sector. The action is

presented in the form of a regionwide

budget for each source sector (i.e., the

electric power industry and other

stationary sources), and the costeffectiveness values are for the ozone

season. The Agency used its estimates of

the average cost effectiveness of

reducing NOX emissions during the

ozone season to develop the budget

components for the electric power

industry and other stationary sources.

The next three columns in the Table

contain the average cost per ton of NOX

annually reduced, the incremental cost

per ton of NOX reduced during the

ozone season, and the incremental cost

per ton of NOX annually reduced. The

average cost per ton of NOX reduced

annually is the annual costs of a source

category complying with a NOX budget

component option divided by the NOX

emissions reductions that occur

throughout the entire year. The

incremental cost per ton of NOX

reduced during the ozone season is the

difference in the annual cost of the

option examined and the next cheapest

option divided by the difference in

seasonal NOX reduction in these two

options. The incremental cost per ton of

NOX reduced annually is the difference

in the annual cost of the option

examined and the next cheapest option

divided by the difference in the annual

NOX reduction in these two options. For

the option with the lowest annual cost

for each source category’s NOX budget

component, the average and incremental

costs are the same, which assumes that

ultimately the cheapest option is no

additional controls, or the baseline.

The EPA has provided these other

measures of cost effectiveness to

provide additional perspective on the

decision that the Agency made for the

level of each source category budget

component. Each of these costeffectiveness measures has advantages

in being used in conjunction with other

factors to make a decision on

environmental controls under certain

circumstances. They each also have

limitations. The annual measures are

valuable since there are NOX reduction

benefits that the public will gain

throughout the year from controls on the

sources covered in this rulemaking.

They do not, however, focus as well on

the primary objectives of the ozone

transport rule of providing reductions of

ozone during the time of year when it

does the most harm and in which

exceedances of the ozone standards are

likely to occur. The incremental

measures are valuable since they show

the additional costs of the additional

reductions from increasing the

stringency of pollution controls.

However, for this rulemaking, it is

difficult to compare the incremental

costs of increasing levels of stringency

for large stationary sources with other

Agency and State analyses that have

been developed in the past. For

instance, because incremental cost

comparisons will differ depending on

the size of the increment in stringency

being considered, care must be used in

using incremental cost estimates from

earlier rulemakings.

The Agency solicits comments on its

use of average seasonal cost

effectiveness as the measure it wants to

rely on to judge the cost effectiveness of

the NOX reductions that will occur from

the NOX budget components that EPA

has chosen for the electric power

industry and other stationary sources.

Commenters offering other measures, or

combinations of cost-effectiveness

measures, that EPA needs to consider,

should provide their rationale for their

views.

The EPA is not choosing to base its

proposed budgets on an expansion of I/

M programs beyond the extent required

by the CAA or otherwise reflected in

existing SIPs in its calculation of State

NOX budgets. The cost effectiveness of

I/M programs in reducing ozone

precursors (including both NOX and

VOC) can vary widely due to differences

in the design and operation of

individual I/M programs. The EPA’s

current estimate of the cost effectiveness

of I/M programs ranges from $500 to

$3,000 per ton of ozone precursor, on an

annualized summer ton basis.9

Although this range suggests that the

cost effectiveness of I/M programs in

reducing ozone precursors (including

both NOX and VOC) may be comparable

to the cost of the utility NOX reductions

proposed in today’s rulemaking, the cost

effectiveness of I/M programs in

reducing NOX alone would be

significantly higher since most of the

ozone precursor reductions from

enhanced I/M programs are VOC

reductions. Both VOC and NOX

reductions are valuable for achieving

local attainment, but as discussed in

section II, Weight of Evidence

Determination of Significant

Contribution, today’s rulemaking
60348 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

10This cost represents the midpoint of the

expected range of $2,600 to $3,500 per ton

(depending on the degree of expansion of the

program), on an annualized summer ton basis, for

both VOC and NOX. All estimates of RFG cost

effectiveness in this rulemaking are presented in

terms of the cost per annualized summer ton of

ozone precursor, i.e., the cost per ton of VOC or

NOX. Cost per annualized summer ton is calculated

as the total cost of the programs divided by the

number of tons that would be reduced annually if

the level of reduction achieved during the summer

were achieved year round. It thus understates the

cost per actual ton of reduction of ozone precursors.

The EPA believes this procedure is appropriate

because the use of RFG reduces other pollutants

besides ozone precursors (e.g., air toxics and CO).

focuses on reducing NOX emissions

since such reductions offer greater

potential for reducing regional transport

than would VOC reductions.

Similarly, EPA is not choosing to base

its proposed budgets on an expansion of

Federal Phase II RFG beyond its current

extent in its calculation of State NOX

budgets. The EPA’s current estimate of

the cost effectiveness of Federal Phase II

RFG ranges from $2,600 to $3,500 per

ton of ozone precursor, on an

annualized summer ton.10 This cost

exceeds the cost of the utility NOX

reductions proposed in today’s

rulemaking. Furthermore, the cost

effectiveness of Federal Phase II RFG

programs in reducing NOX alone would

be significantly higher since most of the

ozone precursor reductions from RFG

would be in the form of VOC reductions

which, while valuable for achieving

local attainment, are not the focus of

today’s action since NOX reductions

offer greater potential for reducing

regional transport.

TABLE III–2.—COST EFFECTIVENESS OF OPTIONS FOR THE OZONE SEASON NOX BUDGET COMPONENTS FOR SELECTED

SOURCE CATEGORIES

[In 1990 dollars per ton of NOX reduced]

Source category: Options for ozone season NOX budget components

Average

cost per ton

of NOX reduced during the

ozone season

Average

cost per ton

of NOX reduced annually

Incremental

cost per ton

of NOX reduced during the

ozone season

Incremental

cost per ton

of NOX reduced annually

Electric Power Industry:

815 thousand tons ..................................................................................................... $1,100 $850 $1,100 $850

652 thousand tons ..................................................................................................... 1,300 1,050 2,100 2,100

489 thousand tons ..................................................................................................... 1,700 1,400 3,600 3,400

391 thousand tons ..................................................................................................... 2,100 1,750 6,350 5,200

326 thousand tons ..................................................................................................... 2,450 2,000 8,700 6,850

Other Stationary Sources

484 thousand tons 1 .................................................................................................. 1,450 750 1,450 750

466 thousand tons 2 .................................................................................................. 1,650 900 4,400 2,150

380 thousand tons 3 .................................................................................................. 2,750 1,400 6,300 3,050

1This measure approximates the emission reductions that would be obtained if Level 1 controls were placed on medium sized sources and

Level 2 controls were placed on large sized sources. The calculation process used to calculate cost for nonutility units selects control measures

(at a State level) so that the cost minimizing set of controls that meet the required emissions reductions are chosen. This approach provides a

downward bias to the costs and cost-effectiveness values compared to any way the States might obtain the emission reductions, including consideration of other factors (e.g., administrative costs that are not included in this analysis). While a least-cost approach simulates either costless

emissions trading or a cost minimizing command and control approach with perfect information, either approach is unlikely to include the smaller

sources used in this analysis. 2This option considers a 70 percent reduction of summer NOX emissions from large sources and RACT controls on medium size sources. This

approach is what OTAG recommended occur, if EPA considered reductions of electric power industry emissions of equivalent to .15 pounds of

NOX per MMBtus, or an 85 percent reduction of uncontrolled levels, whichever is less stringent. The EPA’s proposal for the NOX budget component for the electric power industry is based on a comparable level of controls to the .15/85 percent reduction. 3This measure approximates budgets of an 80 percent control of baseline emissions for large sized sources and Level 1 control on the medium sources. The calculation process used to calculate cost effectiveness on nonutility units provides a downward bias for the reasons explained in the above footnote.

NOTE: The options for electric power industry NOX budget component are based on pollution controls on electric generation units meeting

summer season NOX emission limitations in pounds of NOX per million Btus of heat input of .25, .20, .15, .12, and .10, respectively. The cost-effectiveness calculations are based on implementing these controls through a cap-and-trade program. The controls on which the options for the

NOX budget component for Other Stationary Sources are based are provided in the footnotes. The cost-effectiveness calculations are based on

each State implementing a least-cost approach to compliance.

Considering the $1,000 to $2,000 per

ton average cost-effectiveness range

from Table III–1, and the level of control

achievable with each sector’s NOX

control technologies, EPA believes that

it is reasonable to require the following

levels of reductions: (1) For the electric

power industry, a budget component of

489 thousand tons (which is equivalent

to an average NOX emission rate of 0.15

lb/MMBtu) since it is both cost effective

and achievable, on average, by the

affected sector sources; and (2) for other

stationary sources, a budget component

of 466 thousand tons, which is

consistent with OTAG’s

recommendation that nonutility point

source controls be comparable in

stringency to the selected level of

electric power industry controls, which

for .15 lbs/MMBtus would be 70 percent

control on large-sized sources (e.g.,

boilers greater than 250 MMBtu/hour)

and RACT controls on medium-sized

sources (e.g., sources emitting between

1 and 2 tons per day). The RACT

controls result in NOX reductions

generally in the range of 25–50 percent.

This corresponds closely with the

OTAG recommendation given the

proposed level of electric power

industry controls, and EPA believes it is

a reasonable level of control based on

average cost effectiveness as discussed

above.

For mobile sources, EPA proposes

constructing the budget component by

including: (1) those controls that would

be implemented federally or by States in

the absence of today’s action, and (2)

those controls that are viewed today as

being feasible in the 2007 time frame

and that meet EPA’s proposed NOX costeffectiveness criterion. The EPA did not

include in the proposed mobile source
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60349

11U.S. Environmental protection Agency, ‘‘Round

3 Analysis of Cap-and-Trade Strategies to Lower

NOX Emissions from Electric Power Generation in

OTAG’’, March 25, 1997.

budget component a number of control

measures that offer multipollutant

benefits and hence may be attractive

control measures for local attainment

and maintenance. These measures

include Tier 2 light-duty vehicle and

light-duty truck standards and more

extensive implementation of I/M and

Federal Phase II RFG. When compared

with other available options, these

measures are reasonable control

measures when these measures’ full

range of benefits are considered,

including CO, toxic air pollutants, and

VOC benefits in addition to their NOX

benefits. Some of these measures, such

as I/M, RFG and Clean Fuel Fleets, can

be implemented in specific areas

seeking to meet local air quality

objectives rather than region or

nationwide. While EPA did not choose

to assume their regionwide

implementation in calculating NOX

budgets because their cost effectiveness

for NOX reductions alone did not justify

including them in the set of assumed

controls, EPA continues to believe that

these measures’ nonozone benefits and

VOC benefits (which provide local

ozone reductions but tend not to

provide significant reductions in

regional ozone transport) make them

attractive for areas seeking to meet local

ozone attainment, or maintenance

objectives, or other air quality goals.

Although these strategies were not

included in the budget calculation,

States can opt to implement these

measures as part of their SIP revision in

response to today’s proposal. Each of

these programs is discussed in more

detail below.

The EPA’s approach to the NOX

budget component for the electric power

industry relies on the consideration of

the States using a cap-and-trade

program to reduce emissions from this

source category. The Agency’s analysis

shows that this type of approach is 25

percent more cost effective (lower in

cost per ton reduced) than the use of a

comparable traditional command-andcontrol approach, such as setting ratebased NOX emissions limitations at .15

lbs of NOX per million Btus of heat

input at every source.

The EPA did not examine the

implications of each State setting up its

own trading programs for the electric

power industry, which could occur if

the Agency is unable to work with the

States to put together a viable trading

program across the 23 jurisdictions

covered in this rulemaking. Based on

analysis done for OTAG in the past, the

Agency believes this type of approach

would lead to somewhat higher costs,

but would still be less expensive than a

command-and-control program in every

State. This conclusion is based on work

that EPA did for OTAG, where it

divided a similar area to the one

covered in this rule into five trading

zones versus a single trading zone.11

Although the costs did increase, they

were not dramatically higher. Further

support for this conclusion results from

the examination of EPA’s Regulatory

Analysis supporting this proposed

rulemaking. The Agency found that in

the vast majority of States, electric

generation units would make significant

NOX emissions reductions under a capand-trade system that allowed trading

between all the States covered. This

means that the electric power generation

units that can reduce NOX emissions

most cost-effectively are spread

throughout the region covered by the

Ozone Transport SIP Rulemaking.

In calculating States’ budgets, EPA

assumed implementation of the

following mobile source control

measures in addition to those measures

already implemented or otherwise

promulgated in final form:

Nonroad

• Federal Small Engine Standards,

Phase II

• Federal Marine Engine Standards

• Federal Heavy-Duty (≥50 hp)

Nonroad Standards, Phase I

• Federal Reformulated Gasoline,

Phase II (in statutory and current opt-in

areas)

• Federal Locomotive Standards

• 1997 Proposed Nonroad Diesel

Engine Standards

Highway

• Tier 1 Light-Duty and Heavy-Duty

Vehicle Standards

• Enhanced I/M (serious and above

areas)

• Low Enhanced I/M (rest of OTR)

• Basic I/M (mandated areas)

• Clean Fuel Fleets (mandated areas)

• Federal Reformulated Gasoline,

Phase II (in statutory and current opt-in

areas)

• National Low Emission Vehicle

Standards

• Heavy-Duty Engine 2 g/bhp-hour

standard

• Revisions to Emissions Test

Procedure

With the exception of the Clean Fuel

Fleets, I/M, and RFG programs, all of

these control measures are or will be

implemented nationally (or in the 49

States outside of California). The EPA

assumed that the Clean Fuel Fleets, I/M,

and RFG programs would be

implemented to the extent required by

the CAA or existing SIPs, or as reflected

in current levels of State opt-in to these

programs. The reader is referred to

sections III.B.5 and III.B.6 for a more

extensive discussion of the development

of the highway vehicles and nonroad

budget components, respectively.

At the current time, the standards

presumed for locomotives, marine

engines, small gasoline engine, nonroad

diesel engines, and heavy-duty highway

engines in calculating State NOX

budgets represent the most technically

feasible emissions performance levels

achievable in the 2007 time frame. For

this reason, the Agency did not evaluate

any more stringent standards for these

sources in its calculation of State NOX

budgets.

c. Summary of Measures Assumed in

Proposed Budget Calculation. The EPA

is proposing to calculate the budgets

described in this section by assuming

the application of the most reasonable,

cost-effective controls for the purpose of

achieving regional NOX reductions.

Table III–3 summarizes the controls that

were assumed for each source sector.

More detailed discussions of the

controls assumed are contained in the

sections that describe each sector.

TABLE III–3.—SUMMARY OF NOX CONTROL MEASURES APPLIED IN THE DEVELOPMENT OF PROPOSED STATEWIDE

SEASONAL NOX EMISSIONS BUDGETS *

Emissions Source Sector Controls Applied in Developing Proposed Statewide NOX Emissions

Budgets for 2007

Large Electricity Generating Devices (fossil-fuel burning electric utility

units and nonutility units serving electricity generators 25MWe or

greater).

Statewide seasonal tonnage budget based on applying a NOX emission rate of 0.15 lb/MMBtu on all applicable sources.
60350 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE III–3.—SUMMARY OF NOX CONTROL MEASURES APPLIED IN THE DEVELOPMENT OF PROPOSED STATEWIDE

SEASONAL NOX EMISSIONS BUDGETS *—Continued

Emissions Source Sector Controls Applied in Developing Proposed Statewide NOX Emissions

Budgets for 2007

Nonutility point sources (boilers, reciprocating internal combustion engines, turbines, cement kilns, etc.).70 percent controls on large-sized sources (e.g., >250 MMBtu/hour)

RACT controls on medium-sized sources (e.g., 100–250 MMBtu/hour).

Nonroad Sources (commercial marine engines, small engines such as

lawn and garden equipment, and larger engines such as construction

equipment and locomotives).

Federal small engine standards (Phase II)

Federal marine engine standards (diesel >50 horsepower)

Federal locomotive standards 1997 proposed nonroad diesel engine

standards.

Highway Vehicle Sources (cars, trucks, buses, motorcycles—gas and

diesel highway engines).

National Low Emission Vehicle Program

2004 Heavy-Duty Vehicle Standards.

Revisions to Emissions Test Procedure **

Area (Small Stationary) Sources (open burning, small commercial, industrial and residential fuel combustion devices).Full implementation of programs required by the CAA and outlined in

existing State implementation plans.

* Controls already required under the 1990 Amendments to the CAA and those applied through existing SIPs were assumed in the development of the statewide NOX budgets but are not explicitly listed in this table.

** Other measures used in developing some state budgets include I/M programs (where mandated), Federal Phase II RFG (where mandated

or in areas which have already opted into the program as of the date of today’s rulemaking ), and clean fuel fleet programs. Potential reductions

from Tier 2 light-duty vehicle standards were not incorporated since they are still under review.

In determining what controls to

assume in calculation of the proposed

budgets, EPA considered the

conclusions that were reached in the

OTAG process as well as the costeffectiveness rationale described above.

Any special effort to address ozone

transport, such as today’s action, must

be part of an integrated regulatory

solution developed by EPA and States to

provide national compliance with the

current (1-hour) and new (8-hour)

NAAQS. The OTAG’s air quality

modeling showed that even with the

most stringent control measures that

were evaluated for NOX and VOC, not

all areas would come into attainment

with the current ozone NAAQS. It is

also evident that with no actions to

address ozone transport, some areas will

have ‘‘background levels’’ that will not

allow even aggressive local controls to

bring them into compliance, and others

will face severe measures in an effort to

do so. Therefore, today’s action

complements local programs to address

attainment with the ozone NAAQS. The

EPA recognizes the need to provide

pollutant reductions where it would be

more cost effective to do so rather than

place all of the burden on localities. The

recent RIA in support of the new ozone

standard shows that the last tons of

localized NOX and VOC reduction

needed for meeting that standard in

some areas can easily cost from $5,000

to $10,000 a ton to achieve. Avoiding

such expenditures is a major objective

of today’s action.

3. Proposed Assumptions for Electric

Utilities

This section presents the rationale

and resulting proposed State-by-State

NOX budget components for fossil fuelburning electric utility units under

today’s action. Three different proposed

NOX emission scenarios and their

resulting State-by-State emission

allocations are presented.

a. Affected Entities. The sources of

information used in this section are: (1)

for electric utility units submitted by

utilities to EPA under the requirements

of 40 CFR part 75 (emissions monitoring

provisions of title IV, section 412; and

(2) for nonutility units (e.g., units

owned by Independent Power

Producers), projected by EPA using the

Integrated Planning Model (IPM) from

base year information supplied to the

North-American Electricity Reliability

Council (NERC), Energy Information

Agency (EIA), and trade sources.

Utility emissions represent

approximately 36 percent of the total

anthropogenic NOX emissions after

application of current CAA controls in

the States covered by today’s action.

The calculations described below apply

to large sources that have generators

greater than 25 MWe. The EPA believes

that it is reasonable to assume no further

control of emissions from smaller

sources based on the current availability

of emissions and utilization data for

these sources. While EPA has qualityassured NOX emissions and utilization

data for electric utility units larger than

25 MWe, such data are not currently

available for smaller units. Therefore,

the contribution of the smaller sources

to the utility component of each State’s

budget cannot currently be assessed

with certainty. The EPA solicits

comment on: (1) whether sources equal

to or smaller than 25 MWe should be

included in the utility component of

each State’s budget, and (2) sources of

emissions and utilization data for

sources equal to or smaller than 25

MWe.

Larger sources were found to be large

contributors to NOX emissions and, with

the application of NOX controls, were

found to be able to achieve reductions

cost-effectively. Specifically, EPA

performed an analysis to determine the

cost effectiveness of NOX controls

applied to large utility boilers and how

it compared to other sector NOX

controls. The results indicate that

controlling emissions to an average level

of 0.15 lb/MMBtu was cost effective for

large utility boilers (see section III.B.2.).

This section does not include

combustion units which generate

electricity for purposes internal to a

plant. These units, for the purposes of

the overall State budget, are considered

industrial units and are included in the

corresponding section. Some of these

units (e.g., units with capacity greater

than 25 MWe or the equivalent in

thermal output, measured in MMBtu)

may more appropriately be included

with the utility sector emissions, with

similar required levels of control, since

controls for these units may be as cost

effective as utility unit controls.

Additionally, certain large industrial

combustion sources (e.g., boilers with a

heat input larger than about 250

MMBtu/hour, used only for steam, not

electricity generation) may be able to

achieve levels of control equal to that of

the electric utility units with

comparable cost effectiveness. The EPA

solicits comment on the appropriateness

of including such units in the utility

emissions by assuming the same level of

control from these units as from utility

units.

b. Methodology Used to Determine the

Proposed Electric Utility Budget

Component. The proposed emissions

budget component for electric utilities

(in tons) is calculated as the product of
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60351

two separate components: (1) source

activity level, measured in MMBtu; and

(2) pollutant emission rate, measured in

pounds of pollutant per MMBtu. Since

both components influence the

emissions, it is important to use the

most accurate information when

calculating each component.

i. Proposed Utility Budget Component

Calculation and Alternatives. Four

alternatives were considered for

calculating the utility budget

component (Table III–4).

TABLE III–4.—SUMMARY OF ALTERNATIVES

Alternative Activity level (heat input) NOX rate (lb/MMBtu)

1 .................. Future Activity (current with estimated growth to 2007) ............. Higher of:

(1) 0.15 or

(2) an 85% reduction of historic emission rate.

2 .................. Current Activity ............................................................................ Higher of:

(1) 0.15 or

(2) an 85% reduction of current emission rate.

3 .................. Future Activity (current with estimated growth to 2007) ............. 0.15.

4 .................. Current Activity ............................................................................ 0.15.

After evaluating each alternative, EPA

is proposing to base the electric utility

emissions on a projected future activity

level and a desired emission rate

(scenario 3). The following subsections

discuss each technique separately.

Detailed results of each alternative are

available in the TSD.

Alternative 1: Future Activity With

Historic (or Desired) Emission Rates

This technique involves calculating

the emissions based on a projected

future activity level (e.g., using an

electric utility generation forecasting

model such as IPM) and the higher of:

(1) a desired emission rate, or (2) a rate

resulting from a percent reduction from

some past baseline year emission rate

(e.g., 1990). This was the technique used

in many OTAG analyses. On its face,

this approach may appear to equitably

determine an emissions budget.

However, this requires the

determination of the NOX emission rates

from 1990 for every unit in a State’s

inventory. In addition to the accuracy

problems encountered in determining

an historic emissions rate, this approach

relies on a percent reduction from an

historic rate, which benefits States that

were higher emitters over States that

had cleaner fuels. Thus, EPA believes

that this approach is neither the most

technically accurate nor the most

equitable.

Alternative 2: Current Activity With

Current (or Desired) Emission Rates

This technique involves calculating

emissions based on a current activity

level (e.g., 1995 or 1996) and the higher

of: (1) a desired emission rate, or (2) a

rate resulting from a percent reduction

from a current year (e.g., 1996) for

which accurate emission rates per unit

exist. The benefit of this approach is

that both activity and emission rates are

available for all utility units included in

the emissions budget. This approach

requires that all changes in the

utilization of utility units be

accommodated within the utility budget

component. However, to the extent this

approach relies on percent reduction, it

would benefit currently high emitters

and disadvantage units that installed

controls in order to comply with other

provisions of the Act. Thus, though

simpler (because it relies on current

actual data without projections), this

approach may not be viewed as

equitable.

Alternative 3: Future Activity With

Desired Emission Rate

This technique involves calculating

the utility budget component based on

a future activity level (i.e., inflating the

current measured utilization by an

estimated growth factor) and a desired

emission rate. The benefit of this

approach is that it acknowledges the

inherent inequity of using any past or

current emission rates and treats all

units equally based on a future standard

emission rate (e.g., 0.15 lb/MMBtu).

Further, by projecting future changes in

utilization, this approach more directly

accommodates changes in unit

utilization to the extent such future

utilization can be reasonably projected.

The potential for error in making such

projections is minimized when starting

with actual unit-specific utilizations.

Thus, though more complicated than

the previous technique (because of its

reliance on a projection of industry

growth), this approach is viewed as

more equitable, particularly since other

source categories included in the overall

State-specific budget reflect growth.

Alternative 4: Current Activity With

Desired Emission Rate

This technique involves calculating

emissions based on a current activity

level (e.g., 1995 or 1996) and a desired

future emission rate. Similar to the

above approach, this approach

acknowledges the inherent inequity of

using any past or current emission rates

and treats all units equally based on a

desired standard emission rate (e.g.,

0.15 lb/MMBtu). Unlike the above

approach, however, it uses current

activity to determine the utility budget

component, providing for the highest

degree of accuracy. Changes in the

utilization of utility units must be

accommodated within the utility budget

component. This approach is simple

(because it relies on current actual data

without projections), but it may be

viewed as less equitable for States with

significantly higher projected

utilization.

ii. Seasonal Utilization. The proposed

utility budget component is based on

utilization over the course of a summer

season (i.e., May 1 to September 30).

Utilization can be significantly different

from season to season and the degree of

this difference can vary from State to

State (e.g., some States can have much

higher utilization in the summer due,

for example, to high usage of air

conditioning or shifting load to another

State). Thus, it is important to

accurately characterize the summer

usage of every State separately. Because

of the high seasonal variability, it is less

accurate to simply take total annual

utilization and divide by the number of

summer months. Similarly, because of

the geographic variation, it is less

accurate to take regionwide summer

utilization and equally apportion the

utilization to all States.

There are currently only two sources

of information that provide actual data

and take account for seasonal and State

variations in utilization: (1) the EIA’s

Form 767, and (2) EPA’s Emission

Tracking System containing data

reported by utilities in accordance with

40 CFR part 75. Both sources contain

unit-by-unit utilization; EIA on a

monthly basis and EPA on an hourly
60352 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

12 It should be noted that units owned by

Independent Power Producers were not included in

Table III–5 since neither their 1995 nor their 1996

utilizations are known. The projected 2007

utilization for these units is, however, included in

the utility portion of each State’s budget.

basis. There is, however, one important

difference: while the method used to

determine and report utilization to EIA

can differ significantly from utility to

utility, the information submitted to

EPA is determined and reported using

consistent techniques as required by 40

CFR part 75.

Thus, EPA is proposing to use its

information to determine each unit’s

(and thereby each State’s) utilization for

the period beginning May 1 and ending

September 30. It should be noted that in

the case of units owned by nonutility

sources (e.g., Independent Power

Producers), EPA does not have current

utilization information available. For

the purpose of estimating the emissions

for these units, EPA is proposing to use

the IPM-predicted utilization for the

year 2007. The predicted utilizations are

projected from base year information

supplied to the NERC, EIA and trade

sources.

One way of accounting for State-byState shifts in electricity generation,

from 1 year to the next, during the

period beginning May 1 and ending

September 30, is to calculate the utility

budget component based on a composite

utilization: using the State-by-State

utilization for the higher of 1995 or 1996

(i.e., for each State, using the higher of

its overall 1995 or 1996 summer

utilization). This is the approach

proposed by EPA. Though this approach

results in a slightly exaggerated baseline

utilization, the inflation to emissions is

moderate and the equity that it provides

is potentially significant for some

situations. Table III–5 12 compares the

State-by-State utilizations using the

composite method versus using 1996

only. The impact is most evident on the

District of Columbia (which has a 1995

utilization substantially greater than its

1996 utilization) for which 1996 may

have been an unrepresentative summer.

Another option would be to use the

annual average of the highest 2 out of

3 recent years (e.g., 1995, 1996, and

1997) when data for 1997 becomes

available. The EPA solicits comment on

both approaches.

TABLE III–5.—COMPARISON OF STATE-BY-STATE 1995, 1996 AND ‘‘COMPOSITE’’ UTILITY UNIT SUMMER UTILIZATIONS

State 1995 Utilization (MMBtu)

1996 Utilization (MMBtu)

State-by-State

higher of 1995

or 1996 utilization

Alabama ....................................................................................................................................... 342,060,000 349,950,000 349,950,000

Connecticut ................................................................................................................................... 26,500,000 40,890,000 40,890,000

Delaware ...................................................................................................................................... 30,890,000 33,830,000 33,830,000

District of Columbia ...................................................................................................................... 2,030,000 130,000 2,030,000

Georgia ......................................................................................................................................... 349,310,000 335,330,000 349,310,000

Illinois ............................................................................................................................................ 331,120,000 344,470,000 344,470,000

Indiana .......................................................................................................................................... 511,420,000 512,420,000 512,420,000

Kentucky ....................................................................................................................................... 397,540,000 395,800,000 397,540,000

Maryland ....................................................................................................................................... 130,530,000 123,060,000 130,530,000

Massachusetts .............................................................................................................................. 96,290,000 100,150,000 100,150,000

Michigan ....................................................................................................................................... 280,730,000 287,790,000 287,790,000

Missouri ........................................................................................................................................ 267,710,000 270,240,000 270,240,000

New Jersey ................................................................................................................................... 44,140,000 43,310,000 44,140,000

New York ...................................................................................................................................... 249,260,000 223,360,000 249,260,000

North Carolina .............................................................................................................................. 286,710,000 310,600,000 310,600,000

Ohio .............................................................................................................................................. 549,050,000 565,990,000 565,990,000

Pennsylvania ................................................................................................................................ 445,030,000 481,950,000 481,950,000

Rhode Island ................................................................................................................................ 320,000 11,940,000 11,940,000

South Carolina .............................................................................................................................. 130,150,000 150,370,000 150,370,000

Tennessee .................................................................................................................................... 279,730,000 268,880,000 279,730,000

Virginia .......................................................................................................................................... 150,870,000 136,740,000 150,870,000

West Virginia ................................................................................................................................ 269,840,000 302,850,000 302,850,000

Wisconsin ..................................................................................................................................... 196,840,000 191,730,000 196,840,000

iii. Growth Considerations. In general,

new units built to meet economic

growth are lower emitting than the older

units they augment or replace. Thus,

though the industry’s fuel utilization

may increase over time, the industry’s

average NOX rate may decrease as

newer, cleaner units are built and

operated, and total emissions may or

may not increase.

Two approaches were considered for

accommodating potential emissions

growth under an emissions budget. One

approach was to calculate emissions

based on recent historic utilization, as

was done in the sulfur dioxide program

under title IV of the Act. Under this

approach, States with significant

projected increases in utilization would

be required to either: (1) reduce their

NOX rates further, or (2) burn fuel more

efficiently in order to compensate. For

such States, the ability to trade

emissions regionwide is particularly

attractive because States with low

increases or decreases in utilization can

trade emissions with States having

significantly increased utilization.

An alternative approach was to

project each State’s change in utilization

from current levels to some future year

and set a budget based on that future

year’s utilization. This approach

directly addresses industry growth.

Additionally, this was the type of

approach taken by OTAG in

investigating various State budgets.

Thus, EPA is proposing to use this type

of approach for addressing activity

growth and, as described below, using

the IPM growth projections. However,

there are several other ways in which

growth can be reflected in budget

allocations. For example, recognizing

that several utility companies span more

than one State and that electricity is

dispatched across State boundaries, an

average regional growth rate could be
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60353

applied to each State’s current

utilization. The EPA solicits comment

on these and other approaches

addressing activity growth in

establishing a statewide utility budget

component.

c. Summary and Proposed Utility

Budget Components. For reasons

discussed in the previous section, EPA

is proposing to calculate each State’s

summer season electric utility emissions

using a specific NOX emission rate and

the projected summer season utilization

of the year 2007. Specifically, EPA

proposes calculating each State’s utility

NOX budget component by multiplying:

(1) each State’s summer activity level,

measured in MMBtu, (EPA selected the

higher of each State’s overall 1995 or

1996 summer utilization), by (2) each

State’s projected growth between 1996

and 2007 (using the IPM model), by (3)

a NOX rate of 0.15 lb/MMBtu. The

resulting figure, in lbs, was divided by

2000 (lbs per ton) to determine tons. For

electricity-generating units owned by

nonutilities (e.g., Independent Power

Producers), EPA used their IPMpredicted utilization for 2007 in place of

steps (1) and (2). The EPA compared the

IPM-generated growth factors of each

State to those developed by OTAG for

the electric utility sector in every State.

In general, the IPM-predicted growth

was about 60 percent higher than the

growth projected by OTAG. Regionwide,

the OTAG-predicted growth was about 6

percent from 1996 to 2007, and the IPMgenerated growth was about 15 percent

for the same period. However, for some

States such as Alabama and New Jersey,

the IPM growth factor was lower than

the OTAG growth factor. The TSD

describes in detail how the IPM and

OTAG growth factors were calculated.

For the proposed rule, EPA selected

the IPM’s State-by-State growth factors

over the growth factors developed by

OTAG. Unlike the OTAG electric utility

growth projections, the IPM’s were not

developed separately for each State, but

were developed by analyzing

performance of utilities as a regionwide

system. Therefore, the IPM growth

factors are considered to be more

consistent than the OTAG growth

factors. The EPA solicits comment on

the appropriateness of using the IPM

model to determine State-specific

growth factors for the period between

1996 and 2007. Further, EPA solicits

comment on what other reasonable

regionwide approaches can be used to

develop growth factors.

Table III–6 presents the resulting

proposed utility (and electricitygenerating nonutility) budget

components per State along with the

2007 CAA base.

TABLE III–6.—STATE-BY-STATE BUDGET COMPONENT FOR ELECTRICITY-GENERATING UNITS

State 2007 CAA

base (tons)

Proposed

budget component (tons)

Percent

reduction

Alabama ....................................................................................................................................... 81,704 26,946 67

Connecticut ................................................................................................................................... 5,715 3,409 40

Delaware ...................................................................................................................................... 10,901 4,390 60

District of Columbia ...................................................................................................................... 385 152 61

Georgia ......................................................................................................................................... 92,946 30,158 68

Illinois ............................................................................................................................................ 115,053 31,833 72

Indiana .......................................................................................................................................... 177,888 48,791 73

Kentucky ....................................................................................................................................... 128,688 35,820 72

Maryland ....................................................................................................................................... 35,332 11,364 68

Massachusetts .............................................................................................................................. 28,284 12,956 54

Michigan ....................................................................................................................................... 82,057 25,402 69

Missouri ........................................................................................................................................ 92,313 22,932 75

New Jersey ................................................................................................................................... 14,553 5,041 65

New York ...................................................................................................................................... 39,639 24,653 38

North Carolina .............................................................................................................................. 83,273 27,543 67

Ohio .............................................................................................................................................. 185,757 46,758 75

Pennsylvania ................................................................................................................................ 125,195 39,594 68

Rhode Island ................................................................................................................................ 773 905 ¥17

South Carolina .............................................................................................................................. 43,363 15,090 65

Tennessee .................................................................................................................................... 71,994 19,318 73

Virginia .......................................................................................................................................... 45,719 16,884 63

West Virginia ................................................................................................................................ 83,719 23,306 72

Wisconsin ..................................................................................................................................... 51,004 15,755 69

Total .............................................................................................................................................. 1,596,255 489,000 69

4. Proposed Assumptions for Other

Stationary Sources

a. Affected Entities. This section

presents the rationale and resulting

proposed State-by-State NOX budget

components for other stationary sources,

specifically, the area and nonutility

point source sectors. Area sources of

NOX emissions include, for example,

emissions from wildfires, open burning,

and residential water heaters. Emissions

from area sources represent only 7

percent of total anthropogenic NOX

emissions in the States covered by

today’s action (based on OTAG 2007

CAA emissions). The highest percentage

in any one State is 18 percent.

Nonutility point sources include boilers,

process heaters, reciprocating internal

combustion engines, turbines, cement

kilns and other categories. Emissions

from sources in this sector represent 14

percent of the total anthropogenic NOX

emissions in the States covered by

today’s action, with a range of 3–22

percent.

b. Methodology Used to Determine the

Proposed Area and Nonutility Point

Source Budget Components. The

proposed State-by-State seasonal (May

1–September 30) budget components for

the area and nonutility point sectors

generally reflect the OTAG

recommendations. For area sources,

EPA proposes applying OTAG Level 0

(i.e., no new controls). The EPA is

proposing this level of control because

EPA and OTAG were not able to

identify any reasonable control

measures for sources in this sector.

Controls for wildfires, feasible

alternatives for open burning, and
60354 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

13 If States chose to not seek reductions from

some smaller sources, then the overall costs

estimated for this sector would be expected to

increase.

reasonable cost-effectiveness levels for

control of existing residential water

heaters have not yet been identified for

these States. Therefore, EPA believes

that application of Level 0 controls for

this sector is appropriate.

The OTAG recommendations for the

nonutility point sector are to reduce

emissions from medium- and large-sized

units in a manner equitable with utility

controls. Specifically, OTAG

recommended that large nonutility

sources should meet approximately 70

percent reduction and medium-sized

sources should meet RACT if utilities

are subject to the 0.15 lb/MMBtu utility

limit.

As discussed in section III.B.2., EPA

is proposing to apply the OTAG

recommendations. The EPA believes

that these are reasonable levels of

controls for these sources for the reasons

outlined in section III.B.2.

For purposes of the budget

calculation, EPA believes that it is

reasonable to not calculate reductions

from sources with emissions less than 1

ton per day. The OTAG’s

recommendation to focus controls on

the large sources rather than all sources

for purposes of establishing the budget

is a reasonable approach from an

administrative and data availability

perspective and does not preclude

States from eventually adopting controls

on other sizes or categories of sources as

an alternative way of meeting their

budgets. 13 In addition, emissions data

for the smaller nonutility sources have

more uncertainty, especially source size

and utilization data which are important

in making a budget calculation. As

described in section III.B.2, EPA’s cost

analysis does not key on source sizes;

rather, it is a least cost approach that

considers small, medium and large

sources in determining the overall cost

of the sector budget. Further, controls

on smaller sources are frequently less

cost effective than the same controls on

larger sources. It should also be noted

that the 1 ton per day cutoff for

nonutility sources approximately

corresponds to the 25 MWe cutoff for

utility sources. The EPA solicits

comment on: (1) whether sources with

NOX emissions less than 1 ton per day

should be included in the nonutility

component of each State’s budget, and

(2) sources of emissions and utilization

data for sources with NOX emissions

less than 1 ton per day.

Other approaches to calculating the

nonutility point source budget

component were considered, including

a combined Level 2 for large sources

and Level 1 for smaller sources, an 80

percent reduction from large sources

with Level 1 for the smaller sources (see

Table III–2), and Level 1 or Level 2

applied across the entire sector. A Level

1 approach across the entire sector has

a relatively low cost effectiveness (less

than $1000 per ton) and is not as

equitable as the OTAG

recommendations, considering the

reductions calculated for the electric

utility sector and the importance of the

nonutility point source sector from a

total emissions standpoint. On the other

hand, EPA considered a Level 2

approach across the entire sector to be

less cost effective and administratively

more difficult than the OTAG

recommendations. That is, Level 2

nonutility costs for some of the smaller

sources are likely to be higher in some

cases than the Level 3 utility costs and

the number of units included in the

nonutility point source category is large,

creating an administrative burden. As

discussed in section II.B.3, another

alternative approach would be to

assume a higher level of control for

combustion units which generate

electricity for purposes internal to a

plant. Some of these units may more

appropriately be included with the

utility sector emissions, with similar

required levels of control, since controls

for these units may be as cost effective

as utility unit controls. Additionally,

certain large industrial combustion

sources (e.g., boilers with a heat input

larger than about 250 MMBtu/hour,

used only for steam, not electricity

generation) may be able to achieve

levels of control equal to that of the

electric utility units with comparable

cost effectiveness. The EPA solicits

comment on these and other approaches

for calculating the nonutility point

source budget component.

In applying the proposed controls, the

EPA closely approximated but could not

precisely calculate emissions based on

the size of nonutility point sources as

defined by OTAG because the emissions

inventories available do not have the

level of detail specified in the OTAG

recommendation.

For example:

• The OTAG recommendation

separates boilers by size (i.e., less than

100 MMBtu, between 100 and 250

MMBtu and greater than 250 MMBtu).

Available emissions inventory data are

incomplete especially for the smaller

size boilers.

• The OTAG recommendation

separates stationary reciprocating

internal combustion engines by size

(i.e., less than 4000 horsepower (hp),

between 4000 and 8000 hp, and greater

than 8000 hp). Available emissions

inventory data generally does not

include hp capacities.

• The OTAG recommendation

separates gas turbines by less than

10,000 hp, between 10,000 and 20,000

hp, and greater than 20,000 hp.

Available emissions inventory data

generally do not include hp capacities.

• The OTAG recommendations also

include application of RACT on

medium-sized sources; RACT is

generally considered equal to Level 1

OTAG measures. However, since RACT

may be a case-by-case decision, a

precise forecast of emissions decreases

cannot be made.

In order to calculate the proposed

budget components based on

application to the controls discussed

above, EPA applied 70 percent

reduction controls for boilers greater

than 250 MMBtu/hour and other large

sources (see TSD for details). Boiler size

was determined on an SCC basis (i.e.,

the same level of control was applied to

all boilers within a specific SCC

regardless of the size of individual

boilers). In addition, EPA applied RACT

controls for sources not classed ‘‘large’’

and emitting between 1–2 tons per day;

these reductions are generally in the

range of 25–50 percent emissions

decrease. Where information on boiler

size was not available, EPA assumed

that the source was medium-sized and

applied RACT controls. For other

medium- and large-sized nonutility

sources, EPA applied 70 percent

reduction controls where information

on size of sources was available, and

RACT controls for the remaining

sources (see Budget TSD for details).

Due to the lack of data in the

inventories, especially for internal

combustion engines and turbines, EPA

could not base a budget calculation

precisely on OTAG’s recommendation

of 70 percent reduction for large

sources.

The proposed procedures for

calculating seasonal emissions for these

sectors differs from that used for

utilities because, unlike utilities, day

specific emissions are not available for

each day of the season. In general, a

three-step process is proposed to obtain

summer season emission totals for the

area and nonutility sectors. First, OTAG

emissions reflecting the above controls

are obtained for ‘‘typical’’ summer

weekday, Saturday, and Sunday

operating conditions for each sector for

each State. The underlying procedures

and assumptions used for deriving these

emissions are described in the OTAG

Emissions Inventory Development

Reports (8). Second, the weekday
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60355

emissions are multiplied by 109 (the

total number of weekdays in the period

May 1 through September 30), and the

Saturday and Sunday emissions are

each multiplied by 22 (the total number

of weekends in the 5-month season). In

the third step, these estimates are

summed for each day-type to get the

summer season total emissions by sector

by State.

c. Summary and Proposed Area and

Nonutility Point Source Budget

Components. The resulting proposed

nonutility point and area budget

components are contained in Table III–

7 below along with a comparison for

nonutility point sources to the 2007

CAA base. The area budget components

are not compared to the 2007 base

because no reductions were calculated

for this budget sector. For the nonutility

point sources, EPA applied controls that

approximate the OTAG

recommendations. For the area and

nonutility sectors, we used the summer

weekday, Saturday, and Sunday

emissions that were available in the

OTAG data base for these control levels.

The OTAG growth assumptions were

used for area and nonutility point

source sectors.

TABLE III–7.—PROPOSED BUDGET COMPONENTS FOR NONUTILITY POINT AND AREA SECTORS

[Tons of NOX per Ozone Season]

State

2007 CAA

base

2007 Budget components Percent

reduction

Nonutility point Nonutility point Area Nonutility point

Alabama ............................................................................................................ 47,182 25,131 25,229 47

Connecticut ....................................................................................................... 4,732 4,475 4,587 5

Delaware ........................................................................................................... 5,205 3,206 1,035 38

District of Columbia .......................................................................................... 312 312 741 0

Georgia ............................................................................................................. 34,012 20,472 11,901 40

Illinois ................................................................................................................ 63,642 39,855 7,270 37

Indiana .............................................................................................................. 51,432 35,603 25,545 30

Kentucky ........................................................................................................... 18,817 12,258 38,801 35

Maryland ........................................................................................................... 6,729 4,825 8,123 28

Massachusetts .................................................................................................. 10,683 7,590 10,297 29

Michigan ........................................................................................................... 57,190 35,317 28,126 38

Missouri ............................................................................................................ 12,248 8,174 6,626 33

New Jersey ....................................................................................................... 32,663 26,741 11,388 18

New York .......................................................................................................... 19,889 16,930 15,585 15

North Carolina .................................................................................................. 32,107 21,113 9,193 34

Ohio .................................................................................................................. 50,946 32,799 19,446 36

Pennsylvania .................................................................................................... 64,224 59,622 17,103 7

Rhode Island .................................................................................................... 328 328 420 0

South Carolina .................................................................................................. 34,791 20,097 8,420 42

Tennessee ........................................................................................................ 65,051 32,138 11,991 51

Virginia .............................................................................................................. 23,333 15,529 25,261 33

West Virginia .................................................................................................... 41,510 31,377 4,901 24

Wisconsin ......................................................................................................... 21,209 12,269 10,361 42

Total ................................................................................................... 698,235 466,158 302,350 33

5. Proposed Assumptions for Highway

Vehicles

a. Affected Entities. The highway

vehicle sector encompasses those

sources that normally operate on roads

and highways. All light-duty cars and

trucks, medium-duty trucks, heavy-duty

trucks, motorcycles, and buses are

included in this category. NOX

emissions from these sources, including

the effects of the fuel used to power

these sources, are included in the

estimate of emissions from the highway

vehicle sector. These estimates also

incorporate the effects of emission

control programs which are intended to

reduce emissions from these sources.

b. Methodology Used to Develop the

Proposed Highway Vehicle Budget

Component

i. Budget Component Determination

Method and Alternatives Considered.

The EPA proposes to derive States’

highway vehicle budget component by

estimating the State-by-State NOX

emissions from highway vehicles in

2007. These estimates were developed

by modeling the emissions expected in

2007 from all highway vehicles. The

estimates are based on: (1) a projection

for each State’s number of vehiclemiles-traveled (VMT) by vehicle

category in 2007, as described in section

III.B.5.b.iii; and (2) the estimated

emission rate for each vehicle category

in 2007, assuming implementation of

those measures incorporated in existing

SIPs, measures already implemented

federally, and those additional measures

expected to be implemented federally.

The additional Federal measures

include:

• National Low Emission Vehicle

Standards

• 2004 Heavy-Duty Engine Standards

• Revisions to Emissions Test

Procedure.

These measures either have been

promulgated in final form or are

expected to have been promulgated by

the time today’s proposal is made final.

All of these measures are expected to be

implemented nationwide or in the 49

States other than California and hence

would be in effect in those States

required to submit a transport SIP under

this proposal. Since these measures

would be in effect as of 2007, EPA

believes it is appropriate to reflect the

impact of these measures in 2007 in

calculating States’ highway vehicle

budget components and proposes to do

so. However, it should be noted that the

NLEV program is a voluntary program

that will not take effect until the

Northeastern States and the auto

manufacturers agree to participate.

While EPA expects such an agreement

to be reached, the Agency acknowledges

that such an agreement is not certain at

the current time. Should the
60356 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

14The Trends report method projects national

VMT based on a growth rate of about 2% per year

and allocates VMT to States based on Census

Bureau forecasts of population levels in each State.

Northeastern States and the auto

manufacturers fail to agree to implement

NLEV, EPA proposes to revise States’

highway vehicle budget components

and overall NOX budgets accordingly.

This revision would increase States’

NOX budgets. The EPA requests

comment on this proposal.

The EPA proposes not to incorporate

in its calculation of the highway vehicle

budget component any benefits from

Tier 2 light-duty vehicle standards. The

Agency’s decision to go forward with

such standards is contingent on the

determination that such standards are

necessary to achieve air quality

objectives and can be done so in a costeffective manner. The EPA is currently

engaged in an investigation of these and

other issues related to Tier 2 standards,

and it is premature to assume that such

standards will be implemented prior to

2007. Therefore, EPA cannot at this time

model the impact of a potential set of

Tier 2 standards on emissions from

affected States in 2007. If such

standards are promulgated and

implemented prior to 2007, EPA

proposes to adjust States’ highway

vehicle budget components and overall

NOX budgets accordingly to reflect

implementation of these standards. The

EPA requests comment on this approach

for Tier 2 emission standards.

The EPA proposes to assume full

implementation of other highway

vehicle emission control programs as

required by the CAA or contained in

existing SIPs and maintenance plans in

calculating each State’s highway vehicle

budget component for the purpose of

establishing a statewide NOX emission

budget. This proposal would encompass

I/M programs, Federal Phase II RFG,

Clean Fuel Fleet programs, and other

programs intended to reduce NOX

emissions from highway vehicles. The

EPA further proposes to assume

continued participation in the RFG

program by the mandatory RFG areas

and by those areas which have opted

into the program. The EPA requests

comment on the appropriateness of

these proposals. In particular, EPA

requests comment on whether the extent

of the RFG coverage area chosen in

calculating the highway vehicle budget

component is appropriate, and on

whether the normally-required NOX

reductions from I/M programs in those

areas whose section 182 waivers

currently exempt them from the I/M

NOX performance standard should be

assumed when calculating State

highway vehicle budget components

and overall NOX budgets.

States have the discretion to adopt

additional mobile source control

measures as part of their transport SIP

revision in order to meet their NOX

budget or to meet other air quality

obligations. The EPA agrees with OTAG

that States should consider such control

measures as RFG, I/M programs, and

transportation control measures beyond

those already included in State SIPs.

These measures are applied and

implemented locally rather than

nationally, and in some cases their

specific features are designed locally as

well. The EPA recognizes that States

and localities have more detailed

information on which to base any

decision to expand these programs

beyond their current extent than does

EPA. State and local decisions to

expand these programs can be based on

the unique characteristics of local areas

and the nature of the ozone challenges

they face. In particular, these programs

provide VOC reductions larger than the

NOX reductions they provide, and the

OTAG modeling suggests that VOC

reductions affect local ozone levels but

have limited impact on downwind

ozone levels. The EPA believes these

programs may be attractive to many

States and localities because they can

offer large reductions in VOC, CO, and

toxics emissions, in addition to

reductions in NOX emissions, at a

relatively modest cost. Hence States

may want to adopt these or other local

measures to achieve or maintain local

ozone or CO attainment or to reduce

exposure to toxic air pollutants, as well

as to meet their obligations for NOX

reductions to meet their statewide NOX

budget. States which choose to do so

may be able to adopt less-stringent

controls on other sectors while still

meeting their obligations to reduce NOX

emissions as described in this

rulemaking. For the reasons discussed

above, EPA is not proposing to reduce

the budgets to assume further controls

from Federal or State motor vehicle

measures. The NOX reductions alone

from those measures do not appear

sufficiently cost effective in all of the

areas that would be subject to reduced

budgets, since for some areas there is no

need for local ozone or CO reductions.

ii. Activity Level Projections and

Growth Considerations. The EPA

proposes to use the best available

projections of State VMT levels in 2007

in calculating States’ budget

components for the highway vehicle

sector. For the purposes of providing

estimates in today’s action, EPA has

used the 2007 projections developed by

OTAG. The OTAG projections were

based on actual 1990 VMT levels for

each State, based on State submittals to

OTAG where available or on estimates

generated by the Highway Performance

Monitoring System (HPMS) otherwise.

These base year VMT levels were then

projected to 2007, using growth rates

agreed to or in some cases supplied by

the State. The EPA proposes to use the

state-specific estimates of VMT growth

by vehicle category through 2007, as

developed in the OTAG process, in

calculating States’ highway vehicle

budget components and overall NOX

budgets. In most cases, States accepted

OTAG-proposed growth estimates equal

to those used by the Agency in the

October 1995 edition of its annual

report, ‘‘National Air Pollutant Emission

Trends’’ (16), although several States

submitted (and the OTAG inventory

incorporated) growth estimates that

were significantly lower than the growth

estimates used by the Agency in its 1995

Trends report. One State submitted

growth estimates that were higher than

the 1995 Trends report growth

estimates.

The EPA has considered a number of

options to forecast highway VMT levels

in 2007. For today’s proposal, EPA has

chosen to use the projected VMT levels

used by OTAG. As discussed above,

most of those growth rate estimates were

consistent with EPA’s estimates in its

Trends report.14 Furthermore, the open,

collaborative OTAG process allowed

interested parties to review VMT and

VMT growth estimates when

constructing future year emission

estimates. The EPA encourages each

State subject to today’s action to review

the OTAG 1990 VMT levels and VMT

growth projections again; EPA also

requests each affected State to review

these projections for consistency with

other State projections, including

projections used in SIPs for

nonattainment areas. The EPA expects

that all involved State and local

agencies will coordinate and concur on

any new VMT growth rate submissions,

as should be the case when growth rates

are developed for use in SIP revisions

containing VMT and emissions

projections. The EPA proposes to

incorporate revised VMT growth

projections received from States during

the comment period of today’s action

into its final rule, if appropriately

explained and documented.

The EPA further proposes to use

actual 1995 VMT levels as the base year

for the 2007 inventory projections in the

final rule, rather than continuing to rely

on the 1990 VMT levels. The Agency

believes that the accuracy of projected

2007 VMT levels would be improved by
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60357

using a more recent base year, since the

impact of any deviation between

projected and actual growth rates

through 2007 would be reduced. For

this reason, EPA proposes to use and

requests States to submit VMT data for

1995. The EPA requests comment on

this proposal to use actual 1995 VMT

levels as the base year for projecting

2007 VMT levels and on the use of 1990

VMT levels as the base year in today’s

action.

iii. Seasonal/Weekday/Weekend

Adjustment. The EPA proposes to

project States’ highway vehicle budget

components during the 2007 ozone

season based on the actual number of

weekday and weekend days during the

2007 ozone season. The OTAG

inventory projections, by contrast, were

based on the actual number of weekend

and weekday days during the specific

ozone episodes modeled by OTAG. The

VMT levels on weekdays differ from

VMT levels on weekend days, all other

things being equal, so it is important to

use the proper proportion of weekdays

and weekend days when developing

highway vehicle budget components

and overall State NOX budgets. Since

States must demonstrate compliance

with their NOX budgets over the entire

ozone season in 2007, EPA believes that

the actual number of weekdays and

weekend days during the 2007 ozone

season should be used to calculate

highway vehicle budget components

and overall State NOX budgets. The EPA

requests comment on this proposal.

The EPA also proposes to base its

calculation of State highway vehicle

budget components and overall NOX

budgets on the average temperatures for

the affected months. The OTAG

projections are based on the actual daily

temperature ranges experienced during

the episodes modeled by OTAG. These

temperature ranges may not be

representative of the typical

temperatures experienced during the

whole ozone season as defined in

today’s action, since ozone episodes

tend to occur during periods of aboveaverage temperature. The estimated

highway vehicle budget components

presented in Table III–8 are based on the

OTAG temperature ranges and hence are

based on temperatures that may be

higher than the average temperatures

experienced during the 5 ozone season

months. In its final rulemaking, EPA

will revise its highway vehicle budget

components to reflect the average

temperatures for the affected months.

The impact of these temperature

differences on highway vehicle budget

components is expected to be modest,

because even large differences in

summer temperatures have only a

modest effect on estimated NOX

emissions from highway vehicles. For

example, as temperature goes from 75 to

95 degrees Fahrenheit, NOX emissions

increase by approximately 4 percent.

The actual difference between summer

average and ozone-episode temperature

ranges is considerably smaller than 20

degrees Fahrenheit, so the size of the

temperature adjustment described above

would be correspondingly smaller. The

EPA requests comment on the

appropriateness of this adjustment and

on its proposed use of ozone season

average temperatures instead of ozoneepisode temperatures in developing

States’ highway vehicle budget

components and overall NOX budget.

iv. Comparison to OTAG

Recommendations. The set of

presumptive controls modeled by EPA

to develop the highway vehicle budget

components and overall NOX budgets is

consistent with the OTAG

recommendations. The OTAG

supported expeditious implementation

of Federal measures, including those

listed above. The OTAG also

recommended the continued use of RFG

in the mandated and current opt-in

areas, as reflected in EPA’s proposed

method for calculating highway vehicle

budget components. The OTAG

supported State flexibility to opt into

the RFG program and encouraged areas

which face local nonattainment,

maintenance, or downwind transport

challenges to opt into the RFG program.

The EPA proposes to provide States

with such flexibility in devising

strategies to meet the NOX budgets

outlined in section III.C. The EPA

believes that Federal Phase II RFG can

provide cost-effective reductions in

ozone precursors, since it will reduce

emissions of both VOC and NOX. Phase

II RFG can provide VOC and NOX

reductions at a cost of $2600–3500 per

ton, depending on the amount of fuel

affected by any expansion of the

program offer. Hence EPA encourages

States to consider adopting Federal

Phase II RFG in areas eligible to opt into

the program as part of their revised SIP.

The OTAG further recommended that

‘‘The USEPA should adopt and

implement by rule an appropriate sulfur

standard to further reduce emissions

and assist the vehicle technology/fuel

system [to] achieve maximum long term

performance.’’ The EPA is engaged in an

extensive evaluation of gasoline-based

emission controls as part of its work to

evaluate the need for and benefits and

costs of Tier 2 vehicle emission

standards. This evaluation includes an

examination of the costs and benefits of

gasoline sulfur control. At this time,

however, EPA has not yet defined,

quantified, or evaluated the impact of

sulfur control. Furthermore, EPA has

not at this time decided whether to

require sulfur reductions. Therefore,

EPA believes it is not appropriate to

assume such reductions when

calculating highway vehicle budget

components or overall NOX budgets. If

the Agency does establish gasoline

sulfur standards, EPA proposes to adjust

State highway vehicle budget

components and overall State NOX

budgets to reflect the emissions impact

of such standards on NOX emissions

from highway vehicles in 2007. The

EPA requests comment on this proposal.

The OTAG also recommended that

EPA should evaluate the potential for

reformulation of diesel fuel for reducing

NOX emissions from highway and

nonroad diesel engines. The EPA is

engaged in an examination of the need

for and potential benefits of diesel fuel

reformulation as part of its assessment

of the feasibility of its proposed 2004

heavy-duty highway vehicle standards.

At the present time, however, EPA does

not have sufficient information to

adequately quantify the potential of

diesel fuel reformulation to reduce NOX

emissions or to determine the costs of

various reformulation strategies. Hence

EPA has not incorporated any emission

reductions from diesel fuel

reformulation in its calculation of

highway vehicle budget components or

overall NOX budgets. The EPA will

continue to evaluate the potential of

diesel fuel reformulation to reduce NOX

emissions and enable the proper

functioning of engine-based emission

controls through the collaborative

process developed as a result of the

1995 Statement of Principles. If EPA

does promulgate requirements to

reformulate diesel fuel, EPA proposes to

revise at that time States’ highway

vehicle budget components and overall

NOX budgets to reflect the projected

impact of the required diesel fuel

reformulation on NOX emission from

highway vehicles.

The OTAG called on the States to

adopt inspection and maintenance

programs where required by the CAA.

This recommendation is reflected in

EPA’s proposed method of calculating

the highway vehicle emissions, as

discussed above. The OTAG also called

on the States to consider expanding I/

M programs to urbanized areas of

greater than 500,000 population in the

‘‘fine grid’’ portion of the OTAG region.

The EPA believes that properly

designed and operated I/M programs are

a practicable and cost-effective means of

reducing ozone precursors. These

programs provide VOC reductions as

large or larger than the NOX reductions
60358 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

they provide, while the OTAG modeling

suggests that VOC reductions affect

local ozone levels but have limited

impact on downwind ozone levels.

Therefore, while EPA recognizes that

many of the States subject to today’s

proposal have already implemented or

plan to implement I/M programs, and

while EPA encourages the States to

consider extending I/M programs in

other areas to reduce ozone precursors

as part of their attainment and

maintenance strategy, EPA proposes not

to assume expansion of currentlyrequired I/M programs in calculating

States’ highway vehicle budget

components or overall NOX budgets.

The EPA requests comment on this

proposal. Notwithstanding this

proposal, because I/M programs cause

reductions in NOX emissions implicated

in ozone transport, EPA encourages the

States to consider implementing

effective I/M programs in other areas as

part of their transport SIP.

c. Summary and Proposed Highway

Vehicle Budget Components. The

highway vehicle budget components

presented in Table III–8 were developed

by evaluating the emissions that would

result in 2007 when existing CAA

requirements are met and additional

Federal measures are implemented.

These estimates are based on the 1990

VMT levels and growth rates supplied

to OTAG by the States.

TABLE III–8. BUDGET COMPONENTS FOR HIGHWAY VEHICLES

[Tons of NOX per Ozone Season]

State 2007 CAA

base

Proposed

budget

component

Percent

reduction

Alabama ....................................................................................................................................... 61,205 56,601 8

Connecticut ................................................................................................................................... 23,446 17,392 26

Delaware ...................................................................................................................................... 8,867 8,449 5

District of Columbia ...................................................................................................................... 3,081 2,267 26

Georgia ......................................................................................................................................... 88,363 77,660 12

Illinois ............................................................................................................................................ 91,656 77,690 15

Indiana .......................................................................................................................................... 72,294 66,684 8

Kentucky ....................................................................................................................................... 49,789 46,258 7

Maryland ....................................................................................................................................... 39,941 28,620 28

Massachusetts .............................................................................................................................. 35,308 23,116 35

Michigan ....................................................................................................................................... 91,449 81,453 11

Missouri ........................................................................................................................................ 61,778 55,056 11

New Jersey ................................................................................................................................... 55,783 39,376 29

New York ...................................................................................................................................... 114,234 94,068 18

North Carolina .............................................................................................................................. 80,955 73,056 10

Ohio .............................................................................................................................................. 104,422 92,549 11

Pennsylvania ................................................................................................................................ 81,805 73,176 11

Rhode Island ................................................................................................................................ 7,566 5,701 25

South Carolina .............................................................................................................................. 53,566 49,503 8

Tennessee .................................................................................................................................... 72,907 67,662 7

Virginia .......................................................................................................................................... 88,792 79,848 10

West Virginia ................................................................................................................................ 23,267 21,641 7

Wisconsin ..................................................................................................................................... 46,390 41,651 10

Total ................................................................................................................................... 1,356,864 1,179,477 13

d. Conformity. The CAA section 176

(c) requires federally supported

activities to conform to the purpose of

the SIP. Specifically, the Federal

government cannot support an activity

that causes or worsens air quality

violations or delays attainment.

Conformity applies to nonattainment

and maintenance areas.

The CAA establishes several more

specific requirements regarding how

conformity of Federal highway and

transit activities must be determined.

For example, the emissions expected

from the implementation of

transportation plans and programs must

be consistent with estimates of

emissions from highway vehicles and

necessary emissions reductions

contained in the SIP. The EPA has

promulgated regulations (40 CFR parts

51 and 93) to implement the general and

transportation-related conformity

requirements.

The EPA proposes that neither the

highway vehicle budget components nor

the overall NOX budgets proposed in

this rulemaking change the existing

conformity process or existing SIPs’

motor vehicle emissions budgets under

the conformity rule. The EPA does not

believe that Federal agencies or

Metropolitan Planning Organizations

(MPOs) operating in States subject to

today’s proposal must demonstrate

conformity to the proposed budgets or

the highway vehicle budget component

levels used to calculate the budgets.

Whereas the conformity provisions in

section 176(c) of the CAA apply to

nonattainment and maintenance areas,

the States’ emission budgets apply

statewide. Without greater geographic

disaggregation in the SIP, Federal

agencies and MPOs will not be able to

determine consistency with the

emission estimates in the transport SIP

revision being requested in today’s

proposal. Furthermore, EPA does not

believe that consistency with the

statewide emissions estimates in

transport SIPs can be used to determine

whether or not a transportation or other

Federal activity will cause or worsen

local air quality violations. The

statewide budget does not represent the

level of emissions necessary for

attainment or a reasonable further

progress milestone. In contrast,

attainment demonstrations, 15 percent

SIPs, post-1996 rate-of-progress, and

maintenance plans—SIPs to which EPA

requires conformity—do contain motor

vehicle and other emissions estimates

on which the attainment, maintenance,

or progress demonstration depends.
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60359

6. Proposed Assumptions for Nonroad

Sources

a. Affected Entities. The nonroad

sector encompasses those mobile

sources that normally do not operate on

roads and highways. This sector

includes recreational and commercial

marine engines; small engines such as

those used to power snowmobiles,

chainsaws, or lawn and garden

equipment; larger nonroad engines such

as those used to power agricultural

equipment, construction equipment,

industrial/commercial equipment

(forklifts, pumps, compressors,

generator sets), and mining equipment;

aircraft, and locomotives. Emissions

from these sources, including the effects

of the fuel used to power these sources,

would be included in the estimate of

emissions from the nonroad sector.

These estimates would also incorporate

the effect of emission control programs

which are intended to reduce emissions

from these sources.

b. Methodology Used to Determine the

Proposed Nonroad Budget Component.

i. Budget Component Determination

Method and Alternatives Considered.

The EPA proposes that the States’

nonroad budget component be derived

by estimating the State-by-State NOX

emissions from nonroad engines in

2007. These estimates would be

developed by modeling the emissions

expected in 2007 from all nonroad

engines. The estimates would be based

on: (1) a projection for each State’s

number of engines of each type and

application in 2007; (2) a projection of

the level of activity for each type and

application of nonroad engine in 2007;

and (3) the estimated emission rate for

each engine type and application in

2007, assuming implementation of those

measures incorporated in existing SIPs,

measures already implemented

federally, and those additional measures

expected to be implemented federally.

The additional Federal measures

include:

• Federal Small Engine Standards,

Phase II.

• Federal Marine Engine Standards

(for diesels > 50 horsepower).

• Federal Locomotive Standards.

• 1997 Proposed Nonroad Diesel

Engine Standards.

All of these measures either have been

proposed or are expected to be proposed

in the near future and are sufficiently

well-defined to model their emission

impacts in 2007. These measures are

expected to be implemented nationwide

and hence would be in effect in those

States required to submit a SIP under

this proposal. Since these measures

would be in effect as of 2007, EPA

believes it is appropriate to reflect the

impact of these measures in 2007 in

calculating States’ nonroad budget

components and proposes to do so.

States have the discretion to adopt

additional nonroad control measures as

part of their transport SIP revision in

order to meet their NOX budget or to

meet other air quality obligations. The

EPA agrees with OTAG that States

should consider such control measures

as RFG, scrappage programs, and

activity level control measures beyond

those already included in State SIPs.

These measures are applied and

implemented locally rather than

nationally, and in some cases their

specific features are designed locally as

well. The EPA recognizes that States

and localities have more detailed

information on which to base any

decision to expand these programs

beyond their current extent than does

EPA. State and local decisions to

expand these programs can be based on

the unique characteristics of local areas

and the nature of the ozone challenges

they face. In particular, some of these

programs tend to provide VOC

reductions that are larger than the NOX

reductions they provide, along with

significant CO, toxics, and particulate

matter reductions. The OTAG modeling

suggests that VOC reductions affect

local ozone levels but have limited

impact on downwind ozone levels.

Hence States may want to adopt these

measures to help achieve or maintain

local attainment, as well as to help meet

their obligation to mitigate transport.

States which choose to do so may be

able to adopt less-stringent controls on

other sectors while still complying with

their overall budget.

ii. Activity Level Projections and

Growth Considerations. The EPA

proposes to use the best available

projections of State nonroad activity

levels in 2007 in calculating States’

budget components for the nonroad

sector. For the purposes of providing

estimates in today’s action, EPA has

used the 2007 projections developed by

OTAG. The OTAG projections were

based primarily on estimates of actual

1990 nonroad activity levels found in

the October 1995 edition of EPA’s

annual report, ‘‘National Air Pollutant

Emission Trends.’’ Several States

submitted estimates of their 1990

nonroad activity levels that differed

from these estimates. The OTAG growth

rates were based on growth projections

issued by the Bureau of Economic

Affairs and hence were consistent with

those used by the Agency in its October

1995 ‘‘Trends’’ report. At the present

time, EPA considers the growth

estimates to be reasonable; however, the

Agency requests comment on its

proposal to use the OTAG growth

projections of nonroad activity levels in

calculating the nonroad budget

components and overall NOX budgets

for those States subject to today’s

proposal. The basis of the OTAG growth

projections is explained in greater detail

in OTAG’s Emission Inventory

Development Report, Volume I, pages

11–13.

The EPA encourages each State

subject to today’s proposal to review the

OTAG nonroad growth projections

again; EPA also requests each affected

State to review these projections for

consistency with other State projections,

including projections used in SIPs for

nonattainment areas. The EPA expects

that all involved State and local

agencies will coordinate and concur on

any new nonroad growth rate

submissions, as should be the case

when growth rates are developed for use

in SIP revisions containing nonroad

activity level and emissions projections.

The EPA proposes to incorporate

revised nonroad growth projections

received from States during the

comment period of today’s proposal into

its final rule, if appropriately explained

and documented. The EPA requests

comment on these proposals.

The EPA further proposes to use

estimated historical 1995 nonroad

activity levels as the base year for the

2007 inventory projections in the final

rule, rather than continuing to rely on

the 1990 nonroad activity levels. The

Agency believes that the accuracy of

projected 2007 nonroad activity levels

would be improved by using a more

recent base year, since the impact of any

deviation between projected and actual

growth rates through 2007 would be

reduced. For this reason, EPA proposes

to use its 1997 ‘‘Trends’’ estimate of

1995 nonroad activity levels in its final

rulemaking and requests comment on

this proposal. The EPA also requests

comment on its proposal to use actual

1995 nonroad activity levels as the base

year for projecting 2007 nonroad

activity levels and on the use of 1990

nonroad activity levels as the base year

in today’s action.

iii. Seasonal/Weekday/Weekend

Adjustment. The EPA proposes to

project States’ nonroad budget

components during the 2007 ozone

season based on the actual number of

weekday and weekend days during the

2007 ozone season. The OTAG

inventory projections, by contrast, were

based on the actual number of weekend

and weekday days during the specific

ozone episodes modeled by OTAG.

Nonroad activity levels on weekdays

differ from levels on weekend days, all
60360 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

other things being equal, so it is

important to use the proper proportion

of weekdays and weekend days when

developing nonroad budget component

levels and overall State NOX budgets.

Since States must demonstrate

compliance with their NOX budgets over

the entire ozone season in 2007, EPA

believes that the actual number of

weekdays and weekend days during the

2007 ozone season should be used to

calculate budget components and

overall State NOX budgets. The EPA

requests comment on this proposal.

The EPA also proposes to base its

calculation of the State nonroad budget

components and overall NOX budgets

on the average temperatures for the

affected months. The OTAG projections

are based on the actual daily

temperature ranges experienced during

the episodes modeled by OTAG. These

temperature ranges may not be

representative of the typical

temperatures experienced during the

whole ozone season as defined in

today’s proposal, since ozone episodes

tend to occur during periods of aboveaverage temperature. The estimated

nonroad emissions presented in Table

III–9 are based on the OTAG

temperature ranges and hence are based

on temperatures that may be higher than

the average temperatures experienced

during the five ozone season months. In

its final rulemaking, EPA will revise its

nonroad budget components and overall

NOX budgets to reflect the average

temperatures for the affected months.

The impact of these temperature

differences on nonroad budget

components and overall NOX budgets is

expected to be modest, because even

large differences in summer

temperatures have only a modest effect

on estimated nonroad NOX emissions.

The EPA requests comment on the

appropriateness of this adjustment and

on its proposed use of ozone season

average temperatures instead of ozoneepisode temperatures in developing

States’ nonroad budget components and

overall NOX budget.

iv. Comparison to OTAG

Recommendations. The set of

presumptive controls modeled by EPA

to develop the nonroad sector budget

components for each State is consistent

with the OTAG recommendations. The

OTAG supported expeditious

implementation of Federal measures,

including those listed above. The OTAG

also recommended the continued use of

RFG in the mandated and current optin areas, as reflected in EPA’s proposed

method for calculating the nonroad

budget components. As discussed in

section III.B.5, OTAG supported State

flexibility to opt into the RFG program

and encouraged areas which face local

nonattainment, maintenance, or

downwind transport challenges to opt

into the RFG program. Although current

EPA guidance indicates that Phase II

RFG will not reduce NOX emissions

from nonroad engines, Phase II RFG will

offer significant VOC emission

reduction benefits from nonroad

engines. As discussed in section III.B.5,

EPA encourages States to consider

adopting Federal Phase II RFG in areas

eligible to opt into the program as part

of their revised SIP.

Current EPA guidance also indicates

that changes in fuel sulfur levels,

including any changes that may result

from EPA’s Tier 2 study, would not

affect NOX emissions from gasolinepowered nonroad equipment since such

equipment is not equipped with

catalytic converters. Hence EPA

proposes not to change States’ nonroad

budget components if EPA should

promulgate sulfur standards as a result

of the Tier 2 study or any other EPA

analysis, unless nonroad engines

equipped with catalytic converters

begin to be introduced into the U.S.

marketplace. The EPA requests

comment on this proposal.

As discussed in section III.B.5, OTAG

recommended that EPA should evaluate

the potential for reformulation of diesel

fuel for reducing NOX emissions from

both highway and nonroad diesel

engines. The EPA is engaged in an

examination of the need for and

potential benefits of diesel fuel

reformulation as part of its assessment

of the feasibility of its proposed 2004

heavy-duty highway vehicle emission

standards but has not as of this writing

completed its examination.

Furthermore, EPA does not have

sufficient information at the present

time to quantify adequately the

potential of diesel fuel reformulation to

reduce NOX emissions from nonroad

diesel engines or to determine the costs

of various reformulation strategies. For

these reasons, EPA has not incorporated

any emission reductions from diesel

fuel reformulation in its calculation of

States’ nonroad budget components. If

EPA does promulgate requirements to

reformulate diesel fuel, EPA will

evaluate whether additional research to

determine the impact of diesel fuel

reformulation on NOX emissions from

nonroad engines is needed. The EPA

proposes to defer any consideration of

revisions to States’ nonroad sector

budget components and overall NOX

budgets to reflect the impact of diesel

fuel reformulation on NOX emission

from nonroad engines until such time as

diesel fuel reformulation standards, and

the effect of those standards on nonroad

engine NOX emissions, have been

adequately defined. The EPA requests

comment on this proposal.

c. Summary and Proposed Nonroad

Budget Components. The nonroad

mobile sources sector budget

components presented in Table III–9

were developed by evaluating the

emissions that would result in 2007

when existing CAA requirements are

met and additional Federal measures are

implemented. These estimates are based

on the 1990 activity levels and growth

rates supplied to OTAG by the States.

TABLE III–9.—BUDGET COMPONENTS FOR NONROAD SOURCES

[Tons of NOX per Ozone Season]

State 2007 CAA

base

Proposed

budget component

Percent reduction

Alabama ....................................................................................................................................... 21,742 18,727 14

Connecticut ................................................................................................................................... 11,679 9,581 18

Delaware ...................................................................................................................................... 4,663 4,262 9

District of Columbia ...................................................................................................................... 3,609 3,582 1

Georgia ......................................................................................................................................... 27,151 22,714 16

Illinois ............................................................................................................................................ 66,122 56,429 15

Indiana .......................................................................................................................................... 30,489 27,112 11

Kentucky ....................................................................................................................................... 25,327 22,530 11

Maryland ....................................................................................................................................... 21,717 18,062 17

Massachusetts .............................................................................................................................. 22,865 19,305 16

Michigan ....................................................................................................................................... 29,005 24,245 16
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60361

TABLE III–9.—BUDGET COMPONENTS FOR NONROAD SOURCES—Continued

[Tons of NOX per Ozone Season]

State 2007 CAA

base

Proposed

budget component

Percent reduction

Missouri ........................................................................................................................................ 22,582 19,102 15

New Jersey ................................................................................................................................... 25,150 21,723 14

New York ...................................................................................................................................... 35,934 30,018 16

North Carolina .............................................................................................................................. 22,867 18,898 17

Ohio .............................................................................................................................................. 46,214 42,032 9

Pennsylvania ................................................................................................................................ 33,707 29,176 13

Rhode Island ................................................................................................................................ 2,511 2,074 17

South Carolina .............................................................................................................................. 15,446 12,831 17

Tennessee .................................................................................................................................... 54,710 47,065 14

Virginia .......................................................................................................................................... 29,160 25,357 13

West Virginia ................................................................................................................................ 10,966 10,048 8

Wisconsin ..................................................................................................................................... 19,208 15,145 21

Total ................................................................................................................................... 582,824 500,018 14

C. State-by-State Emissions Budgets

The EPA is proposing a statewide

emission budget for the year 2007 for

each State covered by today’s action.

The proposed statewide budgets were

calculated by summing the budget

components which were calculated as

described above. Budget components

were calculated for the following five

sectors: electric utility, nonutility point,

area, nonroad engines, and highway

vehicles.

The proposed overall budgets to be

achieved by 2007 include reductions

from all Federal programs that would

continue to result in emission

reductions from the compliance date for

the State-adopted rules (between

September 2002 and September 2004

that EPA establishes in its final

rulemaking) to 2007. In 2007, EPA plans

to begin a reassessment of transport. At

that time, EPA will determine how any

new data and tools (such as new air

quality models) should be incorporated.

The portion of the budget over which

States have control (i.e., the non-Federal

portion) would have to be implemented

between September 2002 and September

2004. These concepts are fully

discussed in section V, SIP Revisions

and Approvability Criteria, of this

rulemaking.

The proposed State-by-State budgets

are shown in Table III–10 below. This

table compares the proposed budgets to

the 2007 CAA emissions which were the

starting point for the calculation.

TABLE III–10.—PROPOSED SEASONAL NOX EMISSIONS BUDGET FOR STATES MAKING A SIGNIFICANT CONTRIBUTION TO

DOWNWIND OZONE NONATTAINMENT

[Tons of NOX per Ozone Season]

State 2007 CAA

emissions

Proposed

2007

budget

Percent

reduction

Alabama ................................................................................................................................. 237,062 152,634 36

Connecticut ............................................................................................................................. 50,159 39,445 21

Delaware ................................................................................................................................ 30,671 21,342 28

District of Columbia ................................................................................................................ 8,128 7,054 9

Georgia ................................................................................................................................... 254,373 162,905 35

Illinois ...................................................................................................................................... 343,742 213,077 38

Indiana .................................................................................................................................... 357,647 203,734 100

Kentucky ................................................................................................................................. 261,422 155,667 40

Maryland ................................................................................................................................. 111,841 70,994 36

Massachusetts ........................................................................................................................ 107,437 73,263 32

Michigan ................................................................................................................................. 287,827 194,542 32

Missouri .................................................................................................................................. 195,547 111,890 43

New Jersey ............................................................................................................................. 139,537 104,270 25

New York ................................................................................................................................ 225,281 181,254 19

North Carolina ........................................................................................................................ 228,395 149,803 34

Ohio ........................................................................................................................................ 406,785 233,584 43

Pennsylvania .......................................................................................................................... 322,034 218,671 32

Rhode Island .......................................................................................................................... 11,599 9,429 19

South Carolina ........................................................................................................................ 155,586 105,941 31

Tennessee .............................................................................................................................. 276,653 178,173 35

Virginia .................................................................................................................................... 212,265 162,879 21

West Virginia .......................................................................................................................... 164,362 91,273 44

Wisconsin ............................................................................................................................... 148,171 95,181 35

Total ............................................................................................................................. 334,266,508,374 2,937,005 35
60362 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

D. Recalculation of Budgets

The EPA is proposing statewide

emissions budgets calculated as

described above. The EPA specifically

invites public comment on the overall

approach as well as the individual

elements that were used in these

calculations (e.g., emission factors,

source-specific data, and, growth

assumptions). The EPA is proposing

that the same elements and assumptions

used in the EPA budget calculations be

used by the States as they develop

revisions to their SIPs in response to

today’s proposal. However, EPA

recognizes that changes to these

individual elements may be warranted.

If changes to any of these elements are

appropriate, based on comments

received, EPA proposes recalculating

the budgets with the revised data, as

described below. The intention of this

procedure is to take into account new

information that would replace less

accurate data previously relied upon.

That is, EPA intends to continue to use

the best information available as well as

to assure that the States carry out their

plans to reduce emissions so that, in the

end, the transport of ozone and ozone

precursors is decreased.

For example, for nonutility point

sources, OTAG recommended that

RACT should be considered for

individual medium sized nonutility

point sources. The EPA proposed

budget calculations generally follow the

OTAG recommendations. Because the

definition of RACT may vary from

source-to-source, it is not possible to

precisely forecast emissions reductions

due to RACT on a source-specific basis.

States, however, may have sourcespecific information useful in

determining RACT for sources in their

States and may, therefore, provide more

precise information. With respect to the

large nonutility point sources, missing

data in the OTAG emissions inventories

precludes EPA from precisely following

the recommended definitions of large

sources. Thus, States may provide more

precise information for EPA to use in

the budget calculations. In such cases,

EPA is proposing to recalculate the

budgets to take into account the better

data. New data should be submitted by

the end of the public comment period

so that recalculation would occur prior

to final rulemaking on this proposal; if

any additional data become available

after EPA’s final rulemaking action,

such data could be considered prior to

State submittal of revised SIPs. The EPA

is soliciting comment on this approach.

Similarly, with respect to growth

assumptions, States should use the same

growth rates EPA used to calculate the

proposed budgets, unless better

information indicates that the growth

assumptions should be revised. New

data should be submitted by the end of

the public comment period so that

recalculation would occur prior to final

rulemaking on this proposal; if any

additional data become available after

EPA’s final rulemaking action, such data

could be considered prior to State

submittal of revised SIPs. Changes in

growth that are the result of clearly

identified control strategies which can

be shown to provide real, permanent,

and quantifiable changes in growth,

such as programs to reduce VMT, may

also be creditable toward meeting the

2007 budget. The EPA is soliciting

comment on this approach.

From time to time, EPA updates its

models and inventory estimates to

reflect new information. As models

change, EPA recognizes that projected

emission levels such as those used to

develop the overall State NOX budgets

and sector-specific budget components

proposed in today’s action may change.

Furthermore, EPA recognizes that a set

of control strategies which an earlier

model projects to result in a given level

of emissions may be estimated to result

in a greater or lesser level of emissions,

when evaluated using a newer model,

both in terms of absolute emission

levels and the level of emissions relative

to some other set of control strategies.

Similar to the discussion above on

source-specific data and growth

assumptions, States should use the same

models and inventories EPA used to

calculate the proposed budgets, unless

better information indicates that they

should be revised. Changes that are the

result of changes in EPA models and/or

inventories may lead to an upward or

downward recalculation of the budget

prior to 2007. New data should be

submitted by the end of the public

comment period so that recalculation

would occur prior to final rulemaking

on this proposal; if any additional data

become available after EPA’s final

rulemaking action, such data could be

considered prior to State submittal of

revised SIPs. The EPA requests

comment on whether the State NOX

budgets and budget components for

specific sectors should be revised when

EPA emission and inventory models

change and on whether States’ SIP

revisions in response to today’s action

should be revised. The EPA expects to

address this issue through the process

described in section V, SIP Revisions

and Approvability Criteria, to define the

reporting and implementation

requirements for today’s action.

Finally, it should be noted that it is

possible that EPA may introduce

additional Federal measures after State

emission budgets are defined but before

2007. As discussed in this rulemaking,

EPA is proposing to base State NOX

budgets on a calculation of the NOX

emissions that would result in each

affected State in 2007 assuming the

implementation of a set of reasonable

control measures. Any additional

Federal measures beyond those

described in today’s action would be

implemented regardless of State action

to meet its transport SIP obligations.

The EPA considered two approaches in

this instance: one which would, in

effect, provide emissions reduction

credit to the State and one that does not.

In the first case, one could argue that

real emissions reductions result from

the new Federal measures and,

therefore, the State could receive credits

for these reductions and implement a

smaller portion of its planned emission

reductions. In the second approach, the

State would be required to continue to

implement the measures in its revised

SIP because those measures continue to

be considered reasonable control

measures and all reasonable measures

are needed to mitigate transport. The

EPA believes the latter approach is more

consistent with the framework of this

proposal. However, EPA requests

comment on both of these approaches.

As noted, EPA is proposing to allow

recalculation of NOX budgets as new

information becomes available (e.g.,

changes in response to the promulgation

of additional Federal standards

controlling NOX, changes in EPA

emission and inventory models, changes

adopted in SIPs in any of the underlying

elements or assumptions used to

calculate the State NOX budget, or less

than full implementation of the NLEV

rule). The EPA requests comments on

whether State NOX budgets and budget

components for specific sectors should

be revised in these cases and whether

States’ SIP revisions in response to

today’s action should be revised either

at the request of EPA or upon the

initiation of a State.

IV. Implementation of Revised Air

Quality Standards

A. Introduction

On July 16, 1997, President Clinton

issued a directive to the Administrator

of EPA on implementation of the

revised air quality standards for ozone

and particulate matter. In the directive,

the President laid out a plan for how

these standards are to be implemented.

A central element in the directive is the

incentive it provides States to act and

submit control strategy SIPs early in

exchange for which many areas will
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60363

15Appendix E contains a description of the

controls applied in run 5.

16Appendix E contains a description of the

controls applied in Run 5.

need little or no additional new local

emission reductions beyond those

reductions that will be achieved through

the regional control strategy. This

approach avoids additional burdens

associated with respect to the beneficial

ozone control measures already under

way, while at the same time achieving

public health protection earlier.

The Presidential directive was

published in the Federal Register on

July 18, 1997 (62 FR 38421). The parts

of the directive’s implementation plan

relevant to the regional NOX reduction

strategy proposed in this rulemaking are

described here.

B. Background

Following promulgation of a revised

NAAQS, section 107(d)(1) the CAA

provides up to 3 years for State

governors to recommend and the EPA to

designate areas according to their most

recent air quality. In addition, under

section 172(b) of the CAA, the States

will have up to 3 years from a

nonattainment designation to develop

and submit SIPs to provide for

attainment of the new standard. The

EPA anticipates that it will need the

maximum period allowed under the

CAA to designate areas for the 8-hour

standard. Thus, EPA will designate

areas by July of 2000. Under the Act,

States, therefore, would need to submit

their nonattainment SIPs by 2003.

Section 172(a) of the CAA then allows

up to 10 years plus two 1-year

extensions from the date of designation

for areas to attain the revised NAAQS.

C. Implementation Policy

The implementation plan in the

Presidential Directive has several goals.

Three of these goals are especially

relevant for the NOX reduction strategy

proposed in this rulemaking:

• Reward State and local

governments and businesses that take

early action to reduce air pollution

levels through cost-effective approaches.

• Respond to the fact that pollution

can travel hundreds of miles and cross

many State lines.

• Minimize planning and regulatory

burdens for State and local governments

and businesses where air quality

problems are regional in nature.

To achieve these goals, the

implementation plan includes a policy

for areas that attain the 1-hour standard

but not the new 8-hour standard in

which EPA will follow a flexible

implementation approach that

encourages cleaner air sooner, responds

to the fact that ozone is a regional as

well as local problem, and eliminates

unnecessary planning and regulatory

burdens for State and local

governments. A primary element of the

policy will be the establishment under

section 172(a)(1) of the CAA of a special

‘‘transitional’’ classification for areas

that participate in the NOX regional

strategy proposed in this rulemaking

and/or that opt to submit early plans

addressing the new 8-hour standard.

Because many areas will need little or

no additional new local emission

reductions to reach attainment, beyond

those reductions that will be achieved

through the regional control strategy,

and will come into attainment earlier

than otherwise required, the EPA will

exercise its discretion under the law to

eliminate unnecessary local planning

requirements for such areas. The EPA

will revise its rules for new source

review (NSR) and conformity so that

States will be able to comply with only

minor revisions to their existing

programs in areas classified as

transitional. During this rulemaking,

EPA will also reexamine the NSR

requirements applicable to existing

nonattainment areas in order to deal

with issues of fairness among existing

and new nonattainment areas. The

transitional classification will be

available for any area attaining the 1-

hour standard but not attaining the 8-

hour standard as of the time EPA

promulgates designations for the 8-hour

standard.

Based on the Agency’s review of the

latest OTAG modeling, a regional

approach, coupled with the

implementation of other already

existing State and Federal CAA

requirements, will allow the vast

majority of areas that currently meet the

1-hour standard but would not

otherwise meet the new 8-hour standard

to achieve healthful air quality without

additional local controls. Of the 96 new

counties in the 22-State plus DC region,

92 are projected to come into attainment

as result of the regional NOX reductions

included in the OTAG Run 5 modeling

run.15 A new county is defined as a

county that violates the 8-hour standard

but not the 1-hour standard and is not

located in an area for the 1-hour

standard designated nonattainment as of

July 1997. (In the docket to this

rulemaking is a table with associated

documentation in which EPA lists these

96 new counties in the 22-State plus DC

region with an indication of whether the

county is projected to attain the 8-hour

ozone standard based on the OTAG Run

5 modeling run.)

This county information should be

understood with two caveats. First, this

list of counties is based on air quality

data from 1993–95. The data from this

period will not be the basis for

nonattainment area designations for the

8-hour ozone standard. Those

designations will be made in the 2000

time frame and will be based on the

most recent air quality data available at

that time (1997–1999). Therefore, while

EPA expects that the vast majority of

new counties will attain as a result of

the NOX regional control strategy, the

number of new counties may be more or

less than the number indicated above.

The EPA is also currently updating this

list based on more current air quality

data which will be included in the

docket to the final rule.

Second, the estimate of which

counties will attain the 8-hour standard

is based on the specific assumptions

made by the OTAG in Run 5. Because

the proposed budgets are similar but not

identical to those contained in Run 5,

the estimate may change when this rule

is final and implemented. In addition,

some of the assumptions used to

calculate the proposed budgets may

change in response to comments EPA

may receive on various portions of this

rulemaking. Therefore, the estimate of

which areas will attain the standards

through the final regional NOX strategy

may be higher or lower than the number

indicated above. In addition, areas in

the region covered by the proposed NOX

reduction strategy in this rulemaking

that would exceed the new standard

after the adoption of the regional

strategy, including areas that do not

meet the current 1-hour standard, will

benefit as well because the regional NOX

program will reduce the extent of

additional local measures needed to

achieve the 8-hour standard. In many

cases these regional reductions may be

adequate to meet CAA progress

requirements for a number of years,

allowing areas to defer additional local

controls. In the 22-State plus DC region,

of the 124 counties that violate the 8-

hour standard which are located in an

area designated nonattainment for the 1-

hour standard as of July 1997, 95 are

projected to come into attainment of the

8-hour standard as a result of OTAG

Run 5 regional NOX reductions.16 The

caveats noted above for new counties

also apply to the information presented

here. (In the docket to this rulemaking

is a table with associated documentation

in which EPA lists these 124 counties in

the 22-State plus DC region, including

an indication of whether the area is

projected to attain the 8-hour ozone

standard as a result of regional NOX
60364 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

reductions included in the OTAG Run

5 modeling run.)

To determine eligibility for the

transitional area classification, ozone

areas will follow the approaches

described below based on their status.

1. Areas Eligible for the Transitional

Classification

a. Areas attaining the 1-hour

standard, but not attaining the 8-hour

standard, that would attain the 8-hour

standard through the implementation of

the regional NOX transport strategy for

the East. Based on the OTAG analyses,

areas in the region covered by this

proposal that can reach attainment

through implementation of the regional

transport strategy outlined in this

rulemaking would not be required to

adopt and implement additional local

measures.

When EPA designates these areas

under section 107(d), it will place them

in the new transitional classification if

they would attain the standard through

implementation of the regional transport

strategy and are in a State that by 2000

submits an implementation plan that

includes control measures to achieve

the emission reductions required by this

proposed rule for States in the region

covered by this proposed rule. This is 3

years earlier than an attainment SIP

would otherwise be required. The EPA

anticipates that it will be able to

determine whether such areas will

attain based on the OTAG and other

regional modeling and that no

additional local modeling would be

required.

In addition to areas covered by this

proposed rule which could receive the

transitional classification, areas in the

OTAG region not required to revise their

SIPs in this rulemaking because they do

not significantly contribute to transport

may be able to receive the transitional

classification as well. An area in the

State could be eligible for the

transitional area classification by

submitting a SIP attainment

demonstration in 2000 in which the

State adopts NOX emissions decreases

similar to those EPA proposes to

establish in this rulemaking where NOX

controls are effective for a given area to

demonstrate attainment. The OTAG’s

modeling (in particular, OTAG strategy

Run 5 described in section II.B.2, OTAG

Strategy Modeling) shows that such a

strategy in which a State adopted NOX

emission decreases similar to those EPA

proposes to establish in this rulemaking

would achieve attainment in most of

these areas that would become

nonattainment under the 8-hour

standard.

b. Areas attaining the 1-hour standard

but not attaining the 8-hour standard for

which a regional transport strategy is

not sufficient for attainment of the 8-

hour standard. To encourage early

planning and attainment for the 8-hour

standard, EPA will make the transitional

classification available to areas not

attaining the 8-hour standard that will

need additional local measures beyond

the regional transport strategy, as well

as to areas that are not affected by the

regional transport strategy, provided

they meet certain criteria. To receive the

transitional classification, these areas

must submit an attainment SIP prior to

the designation and classification

process in 2000. The SIP must

demonstrate attainment of the 8-hour

standard and provide for the

implementation of the necessary

emissions reductions on the same time

schedule as the regional transport

reductions. The EPA will work with

affected areas to develop a streamlined

attainment demonstration. By

submitting these attainment plans

earlier than would have otherwise been

required, these areas would be eligible

for the transitional classification and its

benefits and would achieve cleaner air

much sooner than otherwise required.

c. Areas not attaining the 1-hour

standard and not attaining the 8-hour

standard. The majority of areas not

attaining the 1-hour standard have made

substantial progress in evaluating their

air quality problems and developing

plans to reduce emissions of ozonecausing pollutants. These areas will be

eligible for the transitional classification

provided that they attain the 1-hour

standard by the year 2000 and comply

with the appropriate provisions of

section (a) or (b) above depending upon

which conditions they meet.

2. Areas Not Eligible for the Transitional

Classification

Areas that do not attain the 1-hour

standard by 2000 are not eligible for the

transitional classification. For these

areas, their work on planning and

control programs to meet the 1-hour

standard by their current attainment

date (e.g., 2005 for Philadelphia and

2007 for Chicago) will take them a long

way toward meeting the 8-hour

standard. In addition, the regional NOX

reductions proposed in this rulemaking

will also help these areas meet both the

1-hour and 8-hour standards.

While the additional local reductions

that these areas will need to achieve the

8-hour standard must occur prior to

their 8-hour attainment date (e.g., 2010),

for virtually all areas the additional

reductions needed to achieve the 8-hour

standard can occur after the 1-hour

attainment date. This approach allows

them to make continued progress

toward attaining the 8-hour standard

throughout the entire period without

requiring new additional local controls

for attaining the 8-hour standard until

the 1-hour standard is attained. These

areas, however, will need to submit an

implementation plan within 3 years of

designation as nonattainment for

achieving that standard. Such a plan can

rely in large part on measures needed to

attain the 1-hour standard. For virtually

all of these areas, no additional local

control measures beyond those needed

to meet the requirements of Subpart 2 of

part D and needed in response to the

regional transport strategy would be

required to be implemented prior to

their applicable attainment date for the

1-hour standard. Nonattainment areas

that do not attain the 1-hour standard by

their attainment date would continue to

make progress in accordance with the

requirements of Subpart 2; the control

measures needed to meet the progress

requirements under Subpart 2 would

generally be sufficient for meeting the

control measure and progress

requirements of Subpart 1 as well.

V. SIP Revisions and Approvability

Criteria

A. SIP Revision Requirements and

Schedule

For the 1-hour NAAQS, under section

110(k)(5) of the CAA, EPA has the

authority to establish the date by which

a State must respond to a SIP call. This

date can be no later than 18 months

after the SIP call is issued in the final

rulemaking. The EPA is proposing that

the date for SIP submittal be 12 months

after publication of the notice of final

rulemaking. This date is appropriate in

light of the fact that States that are

subject to today’s rulemaking have

already been involved in the OTAG

process. In addition, submitting the

transport SIP by this time will facilitate

area-specific SIP planning required

under Subpart 2 of CAA. Nonattainment

areas required to develop attainment

plans need to know what upwind

reductions to expect and when the

reductions will occur. The EPA believes

that it is appropriate for all areas subject

to this rulemaking—attainment as well

as nonattainment—to meet the same

schedule for making SIP submittals.

Upwind attainment area controls are a

critical element for reducing elevated

levels of ozone and NOX emissions

flowing into the downwind

nonattainment areas.

For the 8-hour NAAQS, under section

110(a)(1) of the Act, EPA believes it has

the authority to establish different
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60365

schedules for different parts of the

section 110(a)(2) SIP revision.

Specifically, EPA proposes to require

first the portion of the 110(a)(2) SIP

revision that contains the controls

required under section 110(a)(2)(D). The

EPA proposes to require that the

110(a)(2)(D) portions of the SIPs

mandated under the 8-hour ozone

NAAQS be submitted within 12 months

of the date of final promulgation of this

rulemaking. This will assist areas that

are ultimately designated nonattainment

for the 8-hour standard in their SIP

planning under section 172(c) of the

CAA and help avoid the kind of delays

due to transport that were experienced

by nonattainment areas for the 1-hour

standard.

Therefore, under section 110(k)(5) for

the 1-hour NAAQS and section 110(a)(1)

for the 8-hour NAAQS, a demonstration

that each State will meet the assigned

statewide emission budget (including

adopted rules needed to meet the

emission budget) must be submitted to

EPA as a SIP revision within 12 months

of the date of final promulgation of this

rulemaking. The EPA solicits comment

on the time frames described above and

elsewhere in this rulemaking. As

discussed in section V.B. of this

rulemaking, EPA will evaluate the SIP

based on particular control strategies

selected and whether the strategies as a

whole provide adequate assurance that

the budget will be achieved. The SIP

revision should include the following

general elements related to the regional

strategy: (1) baseline 2007 statewide

NOX emission inventory (which

includes growth and existing control

requirements)— this would generally be

the emission inventory that was used to

calculate the required statewide budget,

(2) a list and description of control

measures to meet statewide budget, (3)

fully-adopted State rules for the regional

transport strategy with compliance dates

providing for control between

September 2002 and September 2004,

depending on the date EPA adopts in its

final rulemaking, (4) clearly

documented growth factors and control

assumptions, and (5) a 2007 projected

inventory that demonstrates that the

State measures along with national

measures will achieve the State budget

in 2007. The control measures must

meet the requirements for public

hearing, be adopted by the appropriate

board or authority, and establish by

regulation or permit a schedule and date

for each affected source or source

category to achieve compliance. States

should follow existing EPA guidance on

emission inventory development and

growth projections.

The EPA recognizes that States may

need additional detailed guidance on

how to develop effective transportmitigation SIPs. Therefore, the EPA

intends to establish a work group with

States and affected Federal agencies to

determine what types of additional

information and guidance will be

helpful. As discussed below, this work

group will also address what types of

tracking and reporting procedures are

needed to assure States are making

satisfactory progress towards meeting

their required NOX budget once the SIPs

have been put in place.

B. SIP Approval Criteria

1. Budget Demonstration

In response to the final rulemaking,

each State will be required to submit a

SIP revision that clearly demonstrates

how the State will achieve its statewide

NOX budget by 2007. The NOX budget

demonstration should show how

emissions from each sector, or

component, of the NOX emissions

inventory will be addressed and that the

application of the regional strategy

along with existing requirements will

allow total NOX emissions in the State

to be at or below the level of the

required NOX budget by 2007.

In section III, Statewide Emissions

Budgets, of this rulemaking, EPA

described the control strategies that EPA

used in the development of the

statewide NOX emissions budgets. The

EPA believes these measures provide

the most reasonable, cost-effective

means for mitigating significant

interstate transport. In addition, the

control measures are generally

consistent with the OTAG control

strategy recommendations. However,

States have the flexibility to adopt a

different set of control strategies so long

as they achieve the 2007 budget. There

are a variety of different control

programs that could provide the

necessary NOX reductions. States may

wish to consider the strategies that EPA

used for budget development as a

starting point in developing their

specific statewide NOX strategy. Where

States select different control measures

for the various components of their

emissions inventory, they should clearly

define the particular control measures

and document the methods used to

estimate emissions reductions from

implementation of the measures. For

example, if a State elected to adopt more

stringent controls for mobile sources

than were used in EPA’s calculation of

the statewide budget and less stringent

controls on utilities, the State would

identify the additional regulations that

would be applied to the mobile sources

and the different limits that would be

applied to utilities. The State would

submit fully adopted rules for those

sectors with documentation of the

projected emissions reductions the

particular control measures would

achieve, along with the rules for the

other sectors, and a demonstration that

the overall control strategy when

applied to the baseline 2007 emissions

inventory would achieve the statewide

2007 emission budget. The entire NOX

emissions inventory must be accounted

for in the demonstration.

As discussed in section III.D,

Recalculation of Budgets, if a State has

more precise growth estimates and

control assumptions that it wishes to

use in developing its NOX budget

demonstration, and EPA agrees they are

appropriate, EPA will recalculate the

statewide budget based on those revised

numbers. Because any justifiable lower

growth estimates from the State would

be used in EPA’s budget calculation,

lower growth could not be considered as

part of a State’s NOX control strategy to

attain the budget (unless the change in

growth is the result of clearly identified

control strategies which can be shown

to provide real, permanent, and

quantifiable changes in growth).

2. Control Strategies

All the control strategies a State

selects to meet its NOX budget must

provide real, permanent, quantifiable,

and enforceable reductions. These

attributes are consistent with those

required of all SIP revisions (40 CFR

part 51). Control strategies are generally

composed of enforceable limits or

measures applied to a source or group

of sources (i.e., sector) for the purpose

of reducing emissions. Control strategies

may be expressed as either a tonnage

limit, an emission rate, or a specific

technology or measure. Considerations

in addition to compliance with its NOX

budget, such as local impacts, may lead

to selection of a particular strategy over

others. In terms of staying within an

emissions budget, the effectiveness of

the different strategies vary

significantly. A control strategy that

employs a fixed tonnage limitation (or

cap) for a source or group of sources

provides the greatest certainty that a

specific level of emissions will be

attained and maintained. With respect

to transport of pollution, an emissions

cap also provides the greatest assurance

to downwind States that air emissions

from upwind States will be effectively

managed over time. Control strategies

designed and enforced as an emissions

rate limitation can achieve a measurable

emissions reduction, but the targeted

level of emissions may or may not be
60366 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

reached, depending on the actual

activity level of the affected source(s).

Finally, control strategies designed as a

specific technology or measure have the

greatest uncertainty for achieving a

targeted emissions level due to

uncertainty in both the activity level of

the affected source(s) and uncertainty in

the effectiveness of the technology or

measure.

Based on the desire to establish

control strategies with the greatest

environmental certainty of providing for

achievement and maintenance statewide

NOX emissions budget, EPA would

recommend that to the maximum extent

practicable, all control strategies be

based on a fixed level of emissions for

a source or group of sources. However,

EPA recognizes that this option may be

difficult for some sources because: (1)

the available emissions control options

may be limited, and (2) the techniques

for quantifying mass emissions to

ensure compliance with a tonnage

budget may not be adequate. Therefore,

States may select the most appropriate

type of control strategy to achieve and

maintain the desired emissions

limitation for each source or group of

sources regulated in response to this

rulemaking. To compensate for the lack

of certainty inherent in some types of

control strategies (i.e., control strategies

that do not set fixed tonnage budgets)

and to address rule effectiveness

concerns, States may want to consider

incorporating a compliance margin in

their overall budget calculation. A

compliance margin could be used by

increasing the level of controls in the

overall budget beyond what is required

by this rulemaking. Section VII

discusses an interstate cap-and-trade

program for large combustion sources

that EPA intends to develop, in

conjunction with interested States.

Because this is a proven and costeffective control strategy that provides

maximum flexibility to sources, States

may wish to consider this option as part

of their regional NOX strategy.

The EPA is also considering ways to

extend the cap-and-trade program to

other types of sources. The Agency’s

interest in developing such approaches

is consistent with the goal in the

Implementation Plan for the Revised Air

Quality Standards of working ‘‘with the

States to develop control programs

which employ regulatory flexibility to

minimize economic impacts on

businesses large and small to the

greatest possible degree consistent with

public health protection.’’ The EPA

recognizes that there are important

advantages of developing a broad-based

trading program to provide incentives

for the development of innovative, lowcost ways of controlling emissions from

these sources. Under market-based

approaches like a cap-and-trade

program, there will be an incentive for

sources to identify and adopt pollutionminimizing fuels, energy efficiency

measures, or changes in product mix

that offer the lower cost reduction in

emissions.

The EPA and OTAG have focused on

a cap-and-trade program for large

combustion sources because it assures a

proven method for achieving and

maintaining a fixed level of emissions.

The EPA solicits comments on

approaches that would allow a broader

participation in emissions trading. In

addressing expansion of emissions

trading beyond large combustion

sources, commenters should address

what steps can be taken to quantify

emissions from each source involved in

the program to assure that the emissions

cap is met and the costs to Federal, State

and local governments of administering

such a program.

a. Enforceable Measures Approach.

Enforceable measures include control

strategies expressed as either emission

rate limitations or technology

requirements. These control strategies

do not provide the same environmental

certainty that a specific emissions level

will be met and maintained as

compared to fixed tonnage budgets.

However, these control requirements are

an appropriate method for achieving

emissions reductions for many source

sectors that have limited options for

controlling and directly measuring

emissions.

For control strategies that use

emission rate limitations or technology

requirements the SIP must include the

following elements: (1) the enforceable

emission rate, technology requirement,

or specific measure for each source that,

when applied to year 2007 activity

levels and in aggregate with other

controls, would meet the statewide

emissions budget; (2) the projected

activity level for each source or group of

sources, as appropriate; (3) other factors

necessary to calculate the effect of the

control requirements (e.g., speeds and

temperature for mobile sources

necessary to calculate emissions); (4)

emissions rate and activity level

measurement and emissions estimation

protocols for all sources, or group of

sources; (5) reporting protocols for

emission rate, activity level, and

emissions for all sources, or group of

sources (EPA intends to address these

requirements in a supplemental EPA

rulemaking); (6) enforcement

mechanisms, including compliance

schedules for installation and operation

of all control requirements and

institution of all compliance processes

by the date between September 2002

and September 2004 that EPA

establishes in its final action on this

proposal; and (7) requirements for

adequate penalties on the sources for

exceeding applicable emissions rates or

failing to properly install or operate

control technologies or carry-out

compliance measures.

A State or groups of States may

choose to develop, adopt and

implement trading programs for sources

affected by enforceable measures. Such

trading programs should be consistent

with EPA guidance on trading,

including the Economic Incentive

Program rules and guidance as well as

guidance provided on Open Market

Trading. Such approaches could be

adopted by States to help achieve

emission reductions cost effectively.

The EPA does not anticipate managing

the emissions data and market functions

of these trading programs that do not

incorporate emissions caps.

b. Fixed Tonnage Budgets. Under this

approach, a group of sources would

have their control strategy expressed as

a fixed tonnage budget. Because the

fixed tonnage budget approach is

designed to maintain a specific, fixed

level of emissions, this approach does

not require an enforceable compliance

plan that prescribes exactly how

emissions reductions would be

achieved. If a State elects to use a fixed

tonnage budget as a control strategy, the

State would have two options for

implementing the program. The State

may choose to join the cap-and-trade

program that EPA proposes to develop

and assist in implementing for sources

in cooperation with interested States

(this program is discussed in section

VII, Model Cap-and-Trade Program, of

this rulemaking), or the State may

choose to develop a fixed tonnage

budget regulation separate from EPA’s

program. The EPA cap-and-trade

program will incorporate all necessary

SIP criteria into the program design. If

the State elects to develop a fixed

tonnage budget program separate from

EPA’s program, the State program must

include the following elements: (1) the

total seasonal tonnage emissions

limitation for the category of sources

which shall be enforceable at the source

level by the date between September

2002 and September 2004 that EPA

establishes in its final rulemaking

through emission tonnage limitations or

emission rate limitations that

automatically adjust for growth in

activity levels over time; (2)

requirements to measure and

electronically report all emissions from

each source; and (3) requirements for
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60367

adequate penalties for exceeding an

emissions limitation or emission rate.

To implement a fixed tonnage budget

program, a State or group of States may

choose to develop, adopt and

implement their own cap-and-trade

program. Such trading programs should

be consistent with EPA guidance on

trading, including the Economic

Incentive Program rules and guidance.

The EPA does not anticipate managing

the emissions data and market functions

of these programs.

3. Control Strategy Implementation

As discussed in section I.D.2.e,

Control Implementation and Budget

Attainment Dates, of this rulemaking,

EPA is proposing that States must

implement all of their State-adopted

NOX control strategies by a date

between 3 to 5 years from the SIP

submittal due date. This time frame

would result in an implementation

deadline within the range from

September 2002 and September 2004.

The EPA is seeking comment on which

date within this range is appropriate, in

light of the feasibility of implementing

controls and the need to provide air

quality benefits as expeditiously as

possible. Therefore, for the SIP to be

approvable, State NOX rules must all

have compliance dates providing for

control by the implementation deadline,

which will be specified in the final

rulemaking. The EPA believes this is

necessary to assist ozone areas in

meeting their attainment obligations

under the 1-hour standard and to assure

timely attainment of the 8-hour

standard. The EPA recognizes that the

control measures will not be in place in

time to assist serious ozone areas in

meeting their 1999 attainment date

under the 1-hour standard. This is

unavoidable because of the time needed

to complete this rulemaking and for

States to adopt and implement their

NOX measures. The next attainment

date under the 1-hour standard is 2005

for severe-15 areas. For the 8-hour

standard, the CAA provides for

attainment dates of up to 5 or 10 years

after designations with 2 potential 1-

year extensions. In light of the projected

designation date of 2000, the first

attainment date under the 8-hour

standard could also be 2005. For these

areas, it is important that the regional

NOX control measures be in place by no

later than September 2004—in time to

provide emissions reductions for the

2005 ozone season. Implementing

controls earlier than September 2004, or

at least phasing in some controls, would

improve the chance for minimizing

exceedances in the 3-year period up to

and including the 2005 attainment year.

States required to meet a statewide NOX

budget by 2007 will continue to achieve

additional emissions reductions after

September 2004 from continued phase

in of Federal measures. The EPA will

provide guidance to the States on the

appropriate amount of emission

reduction credit that a State may assume

from Federal measures.

4. Growth Estimates

The EPA believes it is important that

consistent emissions growth estimates

be used for the State’s budget

demonstration and for EPA’s calculation

of the required Statewide emissions

budget. If a State wishes to substitute its

own growth or control information in its

budget analyses and can provide

adequate justification for its alternative

numbers, EPA will evaluate the State’s

submission and may recalculate the

required statewide budget to reflect the

State numbers. As mentioned in the

previous section, because the revised

growth estimates will be included in

EPA’s budget calculation, lower growth

rates could not be considered part of a

State’s NOX control strategy to attain

that budget unless the change in growth

is the result of clearly identified control

strategies that can be shown to provide

real, permanent, and quantifiable

changes in growth. During the comment

period for this proposal, States will have

an opportunity to comment on EPA’s

growth assumptions and justifications

for emissions rates and control

measures. As described in section III.D,

Recalculation of Budgets, EPA

encourages requests for alterations to

the growth estimates or control

assumptions be made during the

comment period for this proposal so

that the budgets given in the final

rulemaking will incorporate the

changes. Addressing these issues prior

to the final rulemaking will allow States

to concentrate their efforts on control

strategy development and rule adoption

procedures during the proposed 12-

month time frame for submitting their

SIP revisions.

5. Promoting End-Use Energy Efficiency

In order to minimize compliance

costs, EPA is interested in allowing

States the maximum flexibility practical

in meeting their NOX budgets. The EPA

believes that achievement of energy

efficiency improvements in homes,

buildings, and industry can be one costeffective component of a comprehensive

State strategy. These energy efficiency

improvements would substantially

reduce control measures required to

meet NOX objectives. To this end, EPA

will be investigating, in consultation

with the Department of Energy’s Office

of Energy Efficiency and Renewable

Energy, how energy efficiency

opportunities can be integrated within

SIPs, while maintaining the requisite

level of confidence that State budgets

will be met. The EPA intends to provide

guidance in this area. The EPA is

requesting comment on how SIPs and

associated processes can allow for the

incorporation of cost-effective, end-use

energy efficiency.

C. Review of Compliance

The EPA believes it is essential that

progress in implementing the regional

control strategy be periodically assessed

after the initial SIP submittal. This will

allow early detection of implementation

problems, such as overestimates of

control measure effectiveness and

underestimates of growth. The EPA will

be carefully tracking State progress and

intends to propose periodic State

reporting requirements in its SNPR.

Because nonattainment areas will be

relying on emissions reductions in other

States to assist them in reaching

attainment, EPA believes that each State

must have an effective program for

tracking progress of the regional

strategy. The EPA intends to establish a

work group of affected States and other

impacted Federal Agencies to determine

what procedures to put in place to

provide adequate assurance that the

necessary emissions reductions are

being achieved. The EPA believes that

tracking efforts should be structured to

avoid unnecessary burdens on States.

Therefore, EPA intends to integrate

activities to track progress on

implementing the regional NOX budget

with existing program requirements

such as periodic emissions inventories

and reporting under title IV for NOX.

The EPA is soliciting comment on what

types of compliance assurance

procedures may be necessary.

The EPA recognizes that success of

the program depends, in part, on the

availability of reliable, comprehensive

inventories of emissions. Currently, EPA

is developing a separate rulemaking that

would require statewide periodic

emissions inventories. This rule would

be an extension of the existing periodic

emission inventory requirement for

nonattainment areas. In regard to the

regional transport strategy, EPA intends

to use these inventories as a tool to

assess progress in implementing the

regional strategy, to determine whether

the States achieved their required

budget by 2007, and for future transport

studies.

If tracking and periodic reports

indicate that a State is not implementing

all of its NOX control measures or is offtrack to meet its budget by 2007, EPA
60368 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

will work with the State to determine

the reasons for noncompliance and what

course of remedial action is needed. The

EPA will expect the State to submit a

plan showing what steps it will take to

correct the problems. Continued

noncompliance with the NOX transport

SIP may lead EPA to make a finding of

failure to implement the SIP, and

potentially implement sanctions, if the

State does not take corrective action

within a specified time period. If

tracking indicates that, due to actual

growth and control effectiveness, the

SIP is not adequate to achieve the

budget, EPA will issue a SIP call under

section 110(k)(5) for States to amend

their NOX control strategy. As discussed

above, EPA is proposing that all Stateadopted NOX strategies must be

implemented by a date within the range

of September 2002 and September 2004.

Shortly after the established

implementation due date, EPA will

begin checking to determine whether

States are meeting all of their SIP

obligations.

In 2007, EPA will assess how each

State’s SIP actually performed in

meeting the Statewide NOX emission

budget. If 2007 emissions exceed the

required budget, the control strategies in

the SIP will need to be strengthened.

The EPA will evaluate the

circumstances for the budget failure and

issue a call for States to revise their

SIPs, as appropriate.

D. 2007 Reassessment of Transport

Today’s proposal addresses the

emissions reductions necessary to

mitigate significant ozone transport

based on analyses using the most

complete, scientifically-credible tools

and data available for the assessment of

interstate transport. As the state of

ozone science evolves over the next 10

years, EPA expects there will be a

number of updates and refinements in

air quality methodologies and emissions

estimation techniques. Therefore, in

2007, the end year for the current

analyses, EPA intends to conduct a new

study to reassess ozone transport using

the latest emissions and air quality

monitoring data and the next generation

of air quality modeling tools.

The study will evaluate the

effectiveness of the regional NOX

measures States have implemented in

response to the final rulemaking action

in assisting downwind areas to achieve

attainment. Modeling analyses will be

used to evaluate whether additional

local or regional controls are needed to

address residual nonattainment in the

post-2007 time frame. The study will

examine differences in actual growth

versus projected growth in the years up

to 2007 as well as expected future

growth throughout the entire OTAG

region.

The study will also review advances

in control technologies to determine

what reasonable and cost-effective

measures are available for purposes of

controlling local and regional ozone

problems.

The EPA expects to seek input from

a wide range of stakeholders such as

State and local governments, industry,

environmental groups, and Federal

agencies for the study. The OTAG

partnership established by the ECOS

and EPA resulted in more technical

information and more air quality

modeling being conducted on regional

ozone transport than ever before.

Because of the success of the OTAG

process, EPA envisions working closely

with ECOS for the transport

reassessment study.

E. Sanctions

1. Failure to Submit

If a State fails to submit the required

SIP provisions, the CAA provides for

EPA to issue a finding of State failure

under section 179(a). (EPA is using the

phrase ‘‘failure to submit’’ to cover both

the situation where a State makes no

submission and the situation where the

State makes a submission that EPA finds

is incomplete in accordance with

section 110(k)(1)(B) and 40 CFR part 51,

Appendix V.) Such a finding starts an

18-month sanctions clock; if the State

fails to make the required submittal

which EPA determines is complete

within that period, one of two sanctions

will apply. If 6 months after the

sanction is imposed, the State still has

not made a complete submittal, the

second sanction will apply. The two

sanctions are: withholding of certain

Federal highway funds and a

requirement that new or modified

sources subject to a section 173 new

source review program obtain

reductions in existing emissions in a 2:1

ratio to offset their new emissions

(section 179(b)).

The EPA promulgated regulations to

implement section 179 that specify the

order in which these sanctions will

apply in the case of State

noncompliance with requirements

under part D of title I of the CAA (40

CFR 52.31). These regulations do not,

however, address the imposition of

sanctions in the case of State failure to

comply with a SIP call under section

110(k)(5) or to make a SIP submission

under section 110(a)(1). Since in today’s

rulemaking EPA is proposing a SIP call

and a requirement for a section 110(a)(1)

submission, EPA believes it is

appropriate to propose the order of

sanctions if States fail to comply with

these requirements. The EPA believes

that the general scheme promulgated for

sanctions should also apply here. Under

this scheme, EPA will generally apply

the 2:1 offset sanction first and the

highway funding sanction second. The

EPA believes the rationale for this

approach provided in the preamble to

the sanctions rule applies equally here

(59 FR 39832, August 4, 1994).

Section 179 sets certain limits on

where mandatory sanctions apply. The

highway funding sanction applies in

designated nonattainment areas and the

2:1 offset sanction applies in areas with

part D NSR programs. However, EPA

has additional authority to impose

sanctions under section 110(m). The

EPA’s authority to impose sanctions

under section 110(m) is triggered by any

finding that a State failed to make a

required SIP submission. However,

there is no mandatory clock for the

imposition of these sanctions. The EPA

may determine whether or not to use

this authority in response to a SIP

failure, and thus they are termed

discretionary sanctions. With the

discretionary sanctions, use of the 2:1

offset sanction is still limited to areas

with part D NSR programs. However,

the highway funding sanction can be

applied in any area. While sanctions

under section 179 apply only to the

deficient area, under section 110(m) the

highway sanction can be applied

statewide, subject to the conditions in

EPA’s discretionary sanctions rule (40

CFR 52.30). Because the mandatory

sanctions would not be applicable in all

areas that may fail to respond to

requirements proposed in today’s

rulemaking, EPA is requesting comment

on whether the discretionary sanctions

should be used in response to a failure

of a State to submit the required SIP

revision.

In addition to sanctions, a finding that

the State failed to submit the required

SIP revision triggers the requirement

under section 110(c) that EPA

promulgate a FIP no later than 2 years

from the date of the finding if the

deficiency has not been corrected. The

FIPs are discussed in the section below.

A State that submits a SIP that is

subsequently disapproved, due to

failure to meet one or more of the

required elements, will be subject to the

same sanctions and FIP consequences as

a State that fails to make the required

submittal.

2. Failure to Implement

If a State fails to implement its SIP,

EPA may also make a finding under

section 179. The finding triggers the
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60369

mandatory sanctions as described

above. The EPA may also choose to

apply discretionary sanctions as a

consequence of failure to implement.

However, a FIP is not triggered.

F. Federal Implementation Plans (FIPS)

1. Legal Framework

The Administrator is required to

promulgate a FIP within 2 years of: (1)

finding that a State has failed to make

a required submittal, or (2) finding that

a submittal received does not satisfy the

minimum completeness criteria

established under section 110(k)(1)(A)

(56 FR 42216, August 26, 1991), or (3)

disapproving a SIP submittal in whole

or in part. Section 110(c)(1) mandates

EPA promulgation of a FIP if the

Administrator has not yet approved a

correction proposed by the State before

the time a final FIP is required to be

promulgated.

2. Timing of FIP Action

The EPA views seriously its

responsibility to address the issue of

regional transport of ozone and ozone

precursor emissions. Decreases in NOX

emissions are needed in the States

named in the rulemaking to enable the

downwind States to first develop plans

to achieve the clean air goals and then

to carry out those plans and actually

achieve clean air for their citizens.

Thus, although the CAA allows EPA up

to 2 years after the finding to

promulgate a FIP, EPA intends to

expedite the FIP promulgation to help

assure that the downwind States realize

the air quality benefits of regional NOX

reductions as soon as practicable. This

is consistent with Congress’s intent that

attainment occur in these downwind

nonattainment areas ‘‘as expeditiously

as practicable’’ (sections 181(a), 172(a)).

Therefore, EPA intends to propose FIPs

at the same time as final action is taken

on this proposed Ozone Transport SIP

Rulemaking. Furthermore, EPA intends

to make a finding and promulgate a FIP

immediately after the SIP submittal due

date for each upwind State that fails to

submit a SIP that meets the terms of the

final rulemaking of this proposal.

As described elsewhere in this

rulemaking, EPA is proposing to require

specific States to decrease their

emissions of NOX in order to reduce the

transport of ozone and ozone precursors

which affects nonattainment areas over

hundreds of miles downwind. This

proposal allows States 12 months to

develop, adopt and submit revisions to

their SIPs in response to the final

rulemaking. The EPA intends to

expeditiously approve SIP revisions that

meet the rulemaking requirements. For

States that fail to make the required

submittal or fail to submit a complete

SIP revision response, EPA would

promulgate a FIP as described in the

above section. Where the SIP is

complete but EPA disapproves it, EPA

would also promulgate a FIP. The EPA

may choose to propose a FIP at the same

time as proposing disapproval of a

State’s response to the final rulemaking.

Thus, EPA intends to move quickly to

promulgate a FIP where necessary. The

EPA solicits comment on the time

frames described above and elsewhere

in this rulemaking .

3. Statewide Emissions Budgets

In the FIP proposal, each State would

be allocated by EPA the same statewide

emissions budget as described

elsewhere in this document. That

statewide budget is given to States that

are found to significantly contribute to

nonattainment in downwind States as

described in section II. The statewide

budget is derived from the set of

reasonable, cost-effective measures

applied to the various source sectors as

discussed in section III.

4. FIP Control Measures

In contrast to the SIP process—where

selection and implementation of control

measures is the primary responsibility

of the State—in the case of a FIP, it is

EPA’s responsibility to select the control

measures for each source sector and

assure compliance with those measures.

Thus, while the FIP would be designed

by EPA to achieve the same total

statewide emissions decrease as that

described in final action on today’s

proposal, the specific control measures

assigned in the FIP could be different

from what a State might choose.

In selecting the specific control

measures for a FIP, EPA would take into

account the administrative feasibility as

well as cost effectiveness of various

control options. In developing the

budget calculations, EPA generally

agreed with the direction of the OTAG

recommendations that EPA develop

Federal measures for certain sources

categories—mobile sources in

particular—and that the States develop

stationary source measures in response

to this rulemaking. It is unlikely that

EPA’s FIP would focus on mobile source

programs such as I/M or transportation

control measures because these

measures are not as cost effective as

others for controlling regional NOX

emissions and because it would be

difficult for a limited Federal staff to

implement such programs, especially

without detailed knowledge of local

concerns and circumstances. For

stationary sources, the EPA budget

calculations include large- and mediumsized stationary sources. As in the case

with mobile sources, a program to

reduce emissions from stationary

sources that is reasonable for States to

implement, may be less feasible for EPA

to implement due to factors such as a

large number of affected sources.

Therefore, for the stationary source

sector, EPA’s FIP would likely propose

to focus controls more on the larger

stationary sources. This approach would

take account of the potential need for

Federal staff to implement the program

in more than one State by reducing the

number of sources affected so that the

program is more manageable. It follows

that greater emissions decreases might

be needed from the remaining set of

stationary sources than is suggested by

the EPA’s statewide budget calculation

(described in section III). That is, to

make up the short-fall in the statewide

budget from medium-sized stationary

sources, additional decreases might be

needed from the large stationary sources

in a FIP program.

5. FIP Trading Program

In order to minimize the burden on

sources, EPA would establish in the FIP

an interstate emissions trading program.

The FIP trading program would be

designed to be compatible with the

emissions trading program described

elsewhere in this rulemaking.

Development of such emissions trading

programs would use the process

identified in the OTAG July 10, 1997

recommendation on trading—a joint

EPA/State effort with appropriate

stakeholder input.

6. Section 105 Grants

The EPA provides annual funding to

States under section 105 of the CAA to

carry out Act-related programs. Where

EPA must develop, adopt and

implement a FIP, the Agency will

consider withholding all or a portion of

the grant funds normally appropriated

to the State. Those funds would be used

by EPA in the FIP work.

G. Other Consequences

If a State is implementing all of its

control measures but is off course to

meet its 2007 budget due to errors in

growth estimates or control

assumptions, EPA will consider issuing

a subsequent SIP call for the State to

revise its implementation strategy.

VI. States Not Covered by This

Rulemaking

Based upon all the available technical

information, the EPA is proposing to

find that the following 15 States in the

OTAG region do not make a significant
60370 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

17Appendix E contains a description of the

controls applied in Run 5.

18Appendix E contains a description of the

controls applied in Run 5.

contribution to downwind

nonattainment: Arkansas, Florida, Iowa,

Kansas, Louisiana, Maine, Minnesota,

Mississippi, North Dakota, Nebraska,

New Hampshire, Oklahoma, South

Dakota, Texas, Vermont. These 15 States

are not required to meet an assigned

Statewide NOX emission budget. Based

upon comments received during the

comment period, as well as any

additional modeling and technical

analyses, these States could be found to

be significant contributors to

nonattainment. If this is the case, EPA

will publish a SNPR.

These States may need to cooperate

and coordinate SIP development

activities with other States. For

example, the OTAG recommendation on

utility NOX controls (see Appendix B)

recognized that the State of Iowa would

work with Wisconsin in developing the

Southeast Wisconsin ozone SIP; that the

State of Kansas would work with

Missouri in the continued progress of

the Kansas City ozone SIP; and that

Oklahoma, Texas, Arkansas, and

Louisiana would share the results of

their urban and regional scale modeling

with Missouri. The EPA also believes

that the 11 States (i.e., Connecticut,

Delaware, Maine, Maryland,

Massachusetts, New Hampshire, New

Jersey, New York, Pennsylvania, Rhode

Island and Vermont) plus the District of

Columbia’s consolidated metropolitan

statistical area (including northern

Virginia) that are included in the OTR

should continue coordinating their

activities through the OTC to provide

for attainment of the ozone NAAQS in

that region.

States with interstate nonattainment

areas for the 1-hour standard and/or the

new 8-hour standard are expected to

work together to reduce emissions to

mitigate local scale interstate transport

problems in order to provide for

attainment in the nonattainment area as

a whole. For example, New Hampshire

should work with Massachusetts for the

Boston-Lawrence-Worcester

nonattainment area. For the 8-hour

standard, parts of local scale interstate

nonattainment areas may be located in

Louisiana and Texas as well as in

Arkansas and Tennessee. These States

should also coordinate their planning

efforts.

In addition, areas in these States may

be able to receive the transitional

classification as described in section IV,

Implementation of Revised Air Quality

Standards. The OTAG’s modeling (in

particular, OTAG strategy Run 5

described in section II.B.2, OTAG

Strategy Modeling) shows that a strategy

in which a State-adopted NOX emission

decreases similar to those EPA proposes

to establish in this rulemaking would

achieve attainment in most of these

areas that would become nonattainment

under the 8-hour standard. If a State

wishes to consider this as a viable

option for meeting its early SIP

requirement and receiving the

transitional area classification, EPA will

work with the State to achieve this.

Section III, Statewide Emission Budgets,

describes EPA’s process for establishing

the statewide NOX emission budgets.

(Note that States not covered by this

rulemaking may be eligible for the

transitional classification by means

other than adopting NOX emission

reductions similar to those in this

proposal. In addition to attaining the 1-

hour standard, by at least 2000, areas in

States not covered by this rulemaking

that do not wish to adopt NOX emission

reductions similar to those in this

proposal must submit an attainment SIP

prior to the designation and

classification process in 2000. The SIP

must demonstrate attainment of the 8-

hour standard and provide for the

implementation of the necessary

emissions reductions on the same time

schedule as the regional transport

reductions.)

The EPA strongly suggests that States

with new nonattainment counties for

the 8-hour standard should consider the

option of this strategy since our analysis

indicates that nearly all new

nonattainment counties are projected to

come into attainment as a result of this

strategy. States will benefit by early

action to aid their cities in these new

counties in the attainment of the 8-hour

standard and receipt of transitional

status which will result in no further

controls on local sources. Of the 10 new

counties in the 15 States that are not

covered by this rulemaking, based on

OTAG modeling, all 10 are projected to

come into attainment as result of the

regional NOX reductions included in the

OTAG Run 5 modeling run.17 A new

county is defined as a county that

violates the 8-hour standard but not the

1-hour standard and is not located in an

area for the 1-hour standard designated

nonattainment as of July 1997. (In the

docket to this rulemaking is a table with

associated documentation in which EPA

lists these 10 new counties in the 15

States with an indication of whether the

county is projected to attain the 8-hour

ozone standard based on the OTAG Run

5 modeling run.)

This county information should be

understood with two caveats. First, this

list of counties is based on air quality

data from 1993–95. The data from this

period will not be the basis for

nonattainment area designations for the

8-hour ozone standard. Those

designations will be made in the 2000

time frame and will be based on the

most recent air quality data available at

that time (1997–1999). Therefore, while

EPA expects that the vast majority of

new counties will attain as a result of

the NOX regional control strategy, the

number of new counties may be more or

less than the number indicated above.

The EPA is also currently updating this

list based on more current air quality

data which will be included in the

docket to the final rule.

Second, the estimate of which

counties will attain the 8-hour standard

is based on the specific assumptions

made by the OTAG in Run 5. Because

the proposed budgets are similar but not

identical to those contained in Run 5,

the estimate may change when this rule

is final and implemented. In addition,

some of the assumptions used to

calculate the proposed budgets may

change in response to comments EPA

may receive on various portions of this

rulemaking. Therefore, the estimate of

which areas will attain the standards

through the final regional NOX strategy

may be higher or lower than the number

indicated above.

In addition, areas in the region not

covered by the proposed NOX reduction

strategy in this rulemaking that would

exceed the new standard after the

voluntary adoption of the regional

strategy, including areas that do not

meet the current 1-hour standard, would

benefit as well because the regional NOX

program would reduce the extent of

additional local measures needed to

achieve the 8-hour standard. In many

cases, these regional reductions may be

adequate to meet CAA progress

requirements for a number of years,

allowing areas to defer additional local

controls. In the 15 States, of the 20

counties that violate the 8-hour standard

which are located in an area designated

nonattainment for the 1-hour standard

as of July 1997, 14 are projected to come

into attainment of the 8-hour standard

as a result of OTAG Run 5 regional NOX

reductions. 18 The caveats noted above

for new counties also apply to the

information presented here. (In the

docket to this rulemaking is a table with

associated documentation in which EPA

lists these 20 counties in the 15 States,

including an indication of whether the

area is projected to attain the 8-hour

ozone standard as a result of regional
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60371

NOX reductions included in the OTAG

Run 5 modeling run.)

States that opt in to meet the early SIP

requirement this way would not be

eligible to participate in the trading

program with the States required in this

rulemaking to revise their SIPs although

they could develop intrastate trading

programs. This limitation is needed to

avoid the movement of emissions, via

trades, from States that do not

contribute to nonattainment to States

that do contribute to nonattainment.

Section V, SIP Revisions and

Approvability Criteria, discusses general

SIP requirements for States that EPA has

found significantly contribute to

downwind nonattainment. The EPA

intends to establish a workgroup with

the affected States to determine what

type of reporting and tracking

mechanisms are needed to assure States

are making steady progress toward

meeting their 2007 budgets. One

important element of tracking will be to

assess actual growth versus projected

growth. While EPA will not be

establishing new reporting requirements

for States exempted from this

rulemaking, EPA intends to periodically

review emissions in the exempted States

to determine the impacts of any

emissions increases on downwind

nonattainment areas. In addition, as

discussed in section V.F, 2007

Reassessment of Transport, in 2007 EPA

will be conducting a reassessment of

transport in the full OTAG region to

evaluate the effectiveness of the regional

NOX measures and whether additional

regional controls are needed.

If States not covered by this

rulemaking choose to adopt budgets

based on the rationale outlined above,

EPA will work with those States to

determine what an appropriate

statewide budget should be. The EPA

would encourage those States to

consider statewide budgets based on

adoption of NOX emission decreases

similar to those EPA proposes herein to

establish for States covered by this

rulemaking.

VII. Model Cap-and-Trade Program

The EPA is planning to develop and

administer an interstate cap-and-trade

program that could be used to

implement a fixed tonnage budget.

States electing to reduce emissions from

the types of sources covered by this

program in order to achieve and

maintain the statewide emissions

budget could voluntarily participate in

this program. Much of the discussion to

date on the development of a cap-andtrade program has focussed on

establishing a cap-and-trade program for

large combustion sources. As noted

earlier, EPA is also considering ways to

extend the cap-and-trade program to

other types of sources.

The EPA is planning to develop a capand-trade program for large combustion

sources because it provides a proven

and cost-effective method for achieving

and maintaining a fixed tonnage budget

while providing maximum compliance

flexibility to affected sources. By

capping emissions, the environmental

integrity of this market-based approach

is assured. For example, as total

electricity generation grows, average

emissions over the ozone season would

not exceed the cap. In addition, the

reductions achieved across sectors will

be those of lowest cost, since each

source will identify and implement the

specific control technology, pollutionminimizing fuel, energy efficiency, or

production mix that offers the greatest

amount of pollution reduction at the

least cost. Overall, implementation of a

regional cap-and-trade program would

likely lower the costs of attaining

reductions through more efficient

allocation of emission reduction

responsibilities, minimize the regulatory

burden for pollution sources, and serve

to stimulate technology innovation.

A number of regulatory programs are

currently in use or under development

that use a cap-and-trade program for

large combustion sources. These

regulatory systems include the EPA’s

Acid Rain Program for SO2 emissions,

the South Coast Air Quality

Management District’s Regional Clean

Air Incentives Market for SO2 and NOX,

and the OTC’s NOX Budget Program.

Experience with these regulatory

programs indicates that establishing a

tonnage budget for large combustion

sources is currently feasible and cost

effective. These approaches exist

because there is a range of options

available for controlling and measuring

emissions from these sources. For

measuring emissions, continuous

emissions monitors currently installed

at most sources participating in these

approaches provide accurate and

complete emissions measurements

which enable the administrators of these

approaches to easily and accurately

track and enforce emissions on a

tonnage basis.

In developing the cap-and-trade

program, EPA will build upon the work

produced by OTAG’s Trading/

Incentives Work Group. Based upon

OTAG’s products and upon experience

from other relevant efforts, a model rule

will be developed that details the

program requirements and provisions of

a cap-and-trade program, including:

affected sources, monitoring

requirements, and market features. In

establishing the specific program

applicability, EPA expects to propose

inclusion of those large combustion

sources that are most cost-effective for

controlling emissions, while also

capturing the majority of NOX emissions

from the stationary source sector. The

monitoring requirements are expected to

be based largely on existing

requirements in 40 CFR Part 75. Market

features of the program will address

such issues as the basic design of the

trading system, the process for setting

emission limitations (e.g., allocation of

allowances, generation performance

standard, etc.), and provisions for

emissions trading and banking. The EPA

will work to develop a cap-and-trade

system with market features that are

easily understood to facilitate maximum

participation, minimum transaction

costs, and maximum cost savings. The

EPA will also take comment on ways to

include a broader set of industrial and

mobile sources within the cap-and-trade

system.

The EPA plans to develop the capand-trade program, in coordination with

States interested in participating in such

a system. The EPA will hold two

workshops in late 1997 to provide States

and stakeholders an opportunity to

comment on the trading program

framework prior to proposal, as

recommended by the OTAG. The

product of these workshops would be a

model rule that EPA would then publish

for comment in the Federal Register

prior to finalization of this proposal.

States electing to participate in this

program would either adopt the model

rule by reference or State regulations

that are consistent with the model rule.

The preamble to the model rule would

outline EPA and State responsibilities

for implementing the program.

Generally, EPA expects that it would be

responsible for managing the emissions

data and market functions of the

program and that States would have the

primary responsibility for enforcing the

requirements of the program.

VIII. Regulatory Analysis

Under Executive Order 12866 (58 FR

51735, October 4, 1993), the Agency

must determine whether the regulatory

action is ‘‘significant’’ and therefore

subject to Office of Management and

Budget (OMB) review and the

requirements of the Executive Order.

The Order defines ‘‘significant

regulatory action’’ as one that is likely

to result in a rule that may: (1) have an

annual effect on the economy of $100

million or more or adversely affect in a

material way the economy, a sector of

the economy, productivity, competition,

jobs, the environment, public health or
60372 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

19This category includes industrial, commercial,

and institutional boilers, reciprocating engines, gas

turbines, process heaters, cement kilns, furnaces at

iron, steel, and glass-making operations, and nitric

acid, adipic acid and other plants with industrial

processes that produce NOX

safety, or State, local, or tribal

governments or communities; (2) create

a serious inconsistency or otherwise

interfere with an action taken or

planned by another agency; (3)

materially alter the budgetary impact of

entitlements, grants, user fees, or loan

programs or the rights and obligations of

recipients thereof; or (4) raise novel

legal or policy issues arising out of legal

mandates, the President’s priorities, or

the principles set forth in the Executive

Order.

Pursuant to the terms of Executive

Order 12866, it has been determined

that this proposal is a ‘‘significant

regulatory action’’ because it will have

an annual effect on the economy of

approximately $2 billion. As such, this

action was submitted to OMB for

review. Any written comments from

OMB to EPA and any written EPA

response to those comments are

included in the docket. The docket is

available for public inspection at EPA’s

Air Docket section, which is listed in

the ADDRESSES section of this preamble.

Based on the 2 years of analysis

conducted by OTAG and other

supplemental data, the Agency

developed an approach that is presented

in this proposal for reducing the

transport of ozone emissions over long

distances by lowering NOX emissions

from major sources. Currently, the

movement of ozone from one region to

another makes compliance with the

existing NAAQS difficult for certain

nonattainment areas. Further, State

efforts to reach attainment of the ozone

standard through local measures can be

very expensive. In essence, this

proposal is a regulatory action designed

to improve the effectiveness and

efficiency of State and EPA efforts to

attain and maintain the NAAQS. The

OTAG recommended that EPA focus on

requiring appropriate States to reduce

summer NOX emissions in three

categories: mobile sources, electric

power plants, and other stationary

sources. The Agency adopted this

approach in developing this proposal to

establish emissions budgets for 22 States

and the District of Columbia. Notably,

the Agency is already establishing

national requirements for mobile source

reductions that OTAG recommended.

Therefore, EPA did not estimate their

impacts in this regulatory analysis.

Agency actions with respect to mobile

sources have been and will be addressed

in separate rulemaking activities that are

described below.

Mobile Sources

A number of EPA programs designed

to reduce NOX and other emissions from

highway vehicles and nonroad engines

have not yet been implemented. Some

of these programs have been

promulgated but have implementation

dates which have not yet arrived. Other

programs have been proposed but have

not been promulgated, and still other

programs are expected to be proposed in

the near future. The following table lists

some of these mobile source control

programs and describes their status as of

the date of this rulemaking.

TABLE VIII–1.—ANTICIPATED MOBILE SOURCE CONTROL MEASURES

Measure Current status

National Low-Emitting Vehicle Standards (NLEV) ................................................................................................ Final; not yet implemented.

2004 Heavy-Duty Vehicle Standards ..................................................................................................................... Proposed.

FTP Revisions ........................................................................................................................................................ Final; not yet implemented.

Federal Small Engine Standards, Phase II ........................................................................................................... Proposal in 1997.

Federal Marine Engine Standards (for diesels >50 hp) ........................................................................................ Proposal in 1997.

Federal Locomotive Standards .............................................................................................................................. Proposed.

1997 Proposed Nonroad Diesel Engine Standards .............................................................................................. Proposal in 1997.

Tier 2 Light-Duty Vehicle Standards ...................................................................................................................... Under study.

All of the programs listed in the

preceding table will be implemented on

a nationwide basis (except NLEV which

is applicable in 49 States). The EPA

continues to evaluate the need for

additional Federal controls on mobile

source emissions and may propose

additional measures as conditions

warrant. In addition, EPA continues to

encourage States to evaluate as part of

their SIPs the appropriateness of mobile

source emission control programs that

can be implemented on a local or

Statewide basis such as I/M programs,

RFG, transportation control measures

and clean-fuel fleets.

As described in section III, Statewide

Emission Budgets, the emission targets

for the mobile source sectors (highway

vehicle emissions and nonroad

emissions) were developed by

estimating the emissions expected to

result from the projected activity level

in 2007. These targets do not assume the

implementation of any additional

programs beyond those already reflected

in SIPs or expected to be implemented

at the Federal level, including those

listed in Table VIII–1. All of these

programs would be implemented even

in the absence of today’s proposed rule.

States and industry will not bear any

additional mobile source control costs

due to this proposal, unless a State

chooses to implement additional mobile

source programs under its own

authority and to correspondingly limit

the scope or reduce the stringency of

new controls on stationary sources. The

EPA presumes a State would do so only

if it found a net savings to its economy

in doing so. Furthermore, the cost of

such state-operated programs will

depend on their specific design, which

EPA is unable to predict. The EPA has

therefore not included the costs of

current or new Federal mobile source

controls in its analysis of the costs of

this proposal. Information on the costs

of the various proposed or promulgated

Federal measures can be found in the

Federal Register notices for the

respective measures.

Electric Power Industry and Other

Stationary Sources

The EPA is proposing to establish a

summer season NOX emissions budget

for 22 States and the District of

Columbia based on reducing emissions

from the electric power industry and

other stationary sources.19 This will

lead to the placement of NOX controls

on operating units in these two

categories that the Agency has not

covered in other specific rulemaking

activities. Therefore, EPA has estimated

the NOX emissions reductions and

annual incremental costs in the year

2005 resulting from this proposal.

The OTAG recognized the value of

market-based approaches to lowering

emissions from power plants and large

industrial sources. It also encouraged

EPA to consider the value of allowing
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60373

20The ozone season in this analysis covers May

1 through September 30.

‘‘banking’’ as a program element in any

trading program that it would want to

run with the States. The Agency agrees

that a market-based approach with

trading and banking is preferable and

wants to work with all States covered by

this rulemaking to establish such a

program. The EPA currently believes

that for such a program to be effective

and administratively practicable, the

program should have an emissions cap

and allow trading between sources in all

the States that are covered. The

Agency’s economic analysis is based on

this view.

Analytical limitations kept EPA from

estimating the costs of a single cap-andtrade program for the electric power

industry and other stationary sources.

The Agency can only estimate the

impacts of a cap-and-trade program

across all States covered in this

rulemaking for the electric power

industry at the current time.

For its analysis, the Agency assumed

that power plants have a trading and

banking program that begins in 2005

with a summer NOX emissions cap of

489 thousand tons. This is the NOX

budget component for the electric power

industry that is discussed earlier in the

preamble. This type of program

represents EPA’s current views of how

a reasonable trading program would be

constructed. The Agency estimates that

close to 800 electric power generating

sources will come under this program.

For other stationary sources, EPA

assumed in its economic analysis that

there would be a regulatory program

that would not allow summer NOX

emissions in 2005 to exceed 466

thousand tons. This is the total NOX

budget component for other stationary

sources discussed earlier in the

Preamble. In this analysis, EPA set an

emissions cap for each State based on its

share of the NOX budget component that

EPA has developed and assumes that

each State places controls on its sources

in a manner that minimizes compliance

costs in that State (a ‘‘least-cost’’

regulatory approach is used). The EPA

estimates that the States would place

controls on about 9,000 other stationary

sources to comply with EPA’s

requirements. Given that the Agency

could not estimate the costs of a single

cap-and-trade program for the electric

power industry and other stationary

sources, the total cost estimate of this

proposal is likely to be overstated to the

extent that trading would occur between

facilities in both groups.

For the electric power industry, EPA

was able to estimate the costs and

emissions changes based on two

possible baseline scenarios for the

future. For an Initial Base Case, EPA

considered only the implementation of

Phase I (RACT requirements) of the OTC

MOU and other existing CAA

requirements. For a Final Base Case,

EPA considered implementation of

Phase II and Phase III of the OTC MOU,

which lowered the NOX emissions

levels in the Northeastern United States

in the baseline. For the other stationary

sources, the Agency was only able to

consider the implementation of Phase I

of the OTC MOU and estimate the NOX

emission reductions and incremental

costs from the Initial Base Case. For the

Final Base Case, EPA knows that the

emissions reductions and incremental

costs are going to be less than would

occur in the Initial Base Case.

Table VIII–2 shows the NOX

emissions levels that EPA predicts will

occur for each source category in the

Initial Base Case and Final Base Case

and after States amend their SIPs to

meet the NOX emission budget

requirements in this proposal. Notably,

some types of control technologies can

be used on a seasonal basis and others

have to be used year round. Because

there are benefits from reducing NOX

throughout the year, the annual and

seasonal changes in NOX emissions are

both reported.20 The EPA’s analysis of

the use of cap-and-trade program for the

electric power industry showed that

there would be significant reductions in

NOX emissions occurring from electric

generation units throughout the area

covered by the proposed rule.

Table VIII–3 shows the annual

incremental costs that the Agency

estimates the regulated community will

incur in 2005, the first full year of

implementation of this rule by the

States in the two Base Cases. The costs

presented here reflect trading across

States for electric power generation

units and cost minimization within

States for other stationary sources. For

the Initial Base Case, the total annual

incremental costs are estimated to be

$2,072 million in 2005. For the Final

Base Case, the total annual incremental

costs are estimated to be lower than

$1,992 million in 2005.

TABLE VIII–2.—NOX EMISSIONS IN 2005 FOR ALTERNATIVE BASE CASES AND AFTER COMPLIANCE WITH THE OZONE

TRANSPORT RULEMAKING

[1,000 NOX tons]

Source category

Initial base case (phase I

OTC MOU)

Final base case (phase II/

III OTC MOU)

Under proposed rule implementation

Ozone season Annual Ozone season Annual Ozone season Annual

Electric Power Industry ..................................................... 1,490 3,497 1,427 3,423 489 2,278

Other Stationary Sources ................................................. 698 1,666 <698 <1,666 466 1,227

Total ........................................................................... 2,188 5,163 <2,125 <5,089 955 3,505

Note: EPA was only able to consider partial and full implementation of the Ozone Transport Commission Memorandum of Understanding for

the electric power industry. Controls on the electric power industry occur through cap-and-trade. Controls on Other stationary sources occur by

States implementing an approach applying least-cost controls.
60374 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE VIII–3.— INCREMENTAL ANNUAL COSTS IN 2005 FOR COMPLIANCE WITH THE OZONE TRANSPORT RULEMAKING

UNDER ALTERNATIVE BASE CASES

[Million 1990 dollars]

Source category

Initial base

case (phase

I OTC

MOU)

Final base

case (phase

II/III OTC

MOU)

Electric Power Industry .................................................................................................................................................... $1,687 $1,607

Other Stationary Sources ................................................................................................................................................. 385 <385

Total .......................................................................................................................................................................... 2,072 <1,992

Note: EPA was only able to consider partial and full implementation of the Ozone Transport Commission Memorandum of Understanding for

the electric power industry. Controls on the electric power industry occur through cap-and-trade. States control Other stationary sources by implementing a least-cost approach.

During the OTAG process, there arose

concern over whether the States would

enter the trading program that EPA

offered to form and that they would

instead end up employing commandand-control approaches to comply with

EPA’s proposed rulemaking

requirements. There were discussions of

the possible application of rate-based

controls on electric generation. In

keeping with these discussions, EPA has

also estimated the costs of this type of

control for electric power generation

units. The EPA estimates that the

electric power industry in the 23

jurisdictions covered by this rulemaking

will incur an annual incremental cost

under the Final Base Case of $2,108

million, if during the ozone season,

these plants are regulated by an

emission limitation of .15 pounds of

NOX per million Btus of heat input.

Under the Initial Base Case, the costs

would be $2,189 million. A comparison

of this cost with that in Table VIII–3

reveals that a cap-and-trade program for

the electric power industry is much less

costly than a traditional rate-based

program.

IX. Air Quality Analyses

As discussed in section III, Statewide

Emissions Budgets, EPA has used a

comparative cost-effectiveness approach

to identify a set of control measures for

achieving the emissions budgets for

States found to make a significant

contribution to downwind

nonattainment (see section II, Weight of

Evidence Determination of Significant

Contribution). These controls are

generally consistent with OTAG’s

recommendations. The OTAG did

perform model simulations to assess the

air quality benefits of a range of regional

strategies. In particular, OTAG strategy

Run 5 (see Appendix E) provides large

air quality benefits over broad portions

of the region. This strategy includes

regional NOX controls similar to what is

being proposed in this rulemaking. The

EPA intends to estimate the impacts of

the proposed statewide emission

budgets using air quality modeling for

inclusion in the SNPR.

X. Nonozone Benefits of NOX

Reductions

In addition to contributing to

attainment of the ozone NAAQS,

decreases of NOX emissions will also

likely help improve the environment in

several important ways. On a national

scale, decreases in NOX emissions will

also decrease acid deposition, nitrates in

drinking water, excessive nitrogen

loadings to aquatic and terrestrial

ecosystems, and ambient concentrations

of nitrogen dioxide, particulate matter

and toxics. On a global scale, decreases

in NOX emissions will, to some degree,

reduce greenhouse gases and

stratospheric ozone depletion. Thus,

management of NOX emissions is

important to both air quality and

watershed protection on national and

global scales. In its July 8, 1997 final

recommendations, OTAG stated that it

‘‘recognizes that NOX controls for ozone

reductions purposes have collateral

public health and environmental

benefits, including reductions in acid

deposition, eutrophication, nitrification,

fine particle pollution, and regional

haze.’’ These and other public health

and environmental benefits associated

with decreases in NOX emissions are

summarized below. (17)

Acid Deposition: Sulfur dioxide and

NOX are the two key air pollutants that

cause acid deposition (wet and dry

particles and gases) and result in the

adverse effects on aquatic and terrestrial

ecosystems, materials, visibility, and

public health. Nitric acid deposition

plays a dominant role in the acid pulses

associated with the fish kills observed

during the springtime melt of the

snowpack in sensitive watersheds and

recently has also been identified as a

major contributor to chronic

acidification of certain sensitive surface

waters.

Drinking Water Nitrate: High levels of

nitrate in drinking water is a health

hazard, especially for infants.

Atmospheric nitrogen deposition in

sensitive watersheds can increase

stream water nitrate concentrations; the

added nitrate can remain in the water

and be transported long distances

downstream.

Eutrophication: NOX emissions

contribute directly to the widespread

accelerated eutrophication of United

States coastal waters and estuaries.

Atmospheric nitrogen deposition onto

surface waters and deposition to

watershed and subsequent transport

into the tidal waters has been

documented to contribute from 12 to 44

percent of the total nitrogen loadings to

United States coastal water bodies.

Nitrogen is the nutrient limiting growth

of algae in most coastal waters and

estuaries. Thus, addition of nitrogen

results in accelerated algae and aquatic

plant growth causing adverse ecological

effects and economic impacts that range

from nuisance algal blooms to oxygen

depletion and fish kills.

Global Warming: Nitrous oxide (N2O)

is a greenhouse gas. Anthropogenic N2O

emissions in the United States

contribute about 2 percent of the

greenhouse effect, relative to total

United States anthropogenic emissions

of greenhouse gases. In addition,

emissions of NOX lead to the formation

of tropospheric ozone, which is another

greenhouse gas.

Nitrogen Dioxide (NO2): Exposure to

NO2 is associated with a variety of acute

and chronic health effects. The health

effects of most concern at ambient or

near-ambient concentrations of NO2

include mild changes in airway

responsiveness and pulmonary function

in individuals with pre-existing

respiratory illnesses and increases in

respiratory illnesses in children.

Currently, all areas of the United States

monitoring NO2 are below EPA’s

threshold for health effects.
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60375

Nitrogen Saturation of Terrestrial

Ecosystems: Nitrogen accumulates in

watersheds with high atmospheric

nitrogen deposition. Because most

North American terrestrial ecosystems

are nitrogen limited, nitrogen deposition

often has a fertilizing effect, accelerating

plant growth. Although this effect is

often considered beneficial, nitrogen

deposition is causing important adverse

changes in some terrestrial ecosystems,

including shifts in plant species

composition and decreases in species

diversity or undesirable nitrate leaching

to surface and ground water and

decreased plant growth.

Particulate Matter (PM): NOX

compounds react with other compounds

in the atmosphere to form nitrate

particles and acid aerosols. Because of

their small size nitrate particles have a

relatively long atmospheric lifetime;

these small particles can also penetrate

deeply into the lungs. PM has a wide

range of adverse health effects.

Stratospheric Ozone Depletion: A

layer of ozone located in the upper

atmosphere (stratosphere) protects

people, plants, and animals on the

surface of the earth (troposphere) from

excessive ultraviolet radiation. N2O,

which is very stable in the troposphere,

slowly migrates to the stratosphere. In

the stratosphere, solar radiation breaks

it into nitric oxide (NO) and nitrogen

(N). The NO reacts with ozone to form

NO2 and molecular oxygen. Thus,

decreasing N2O emissions would result

in some decrease in the depletion of

stratospheric ozone.

Toxic Products: Airborne particles

derived from NOX emissions react in the

atmosphere to form various nitrogen

containing compounds, some of which

may be mutagenic. Examples of

transformation products thought to

contribute to increased mutagenicity

include the nitrate radical, peroxyacetyl

nitrates, nitroarenes, and nitrosamines.

Visibility and Regional Haze: NOX

emissions lead to the formation of

compounds that can interfere with the

transmission of light, limiting visual

range and color discrimination. Most

visibility and regional haze problems

can be traced to airborne particles in the

atmosphere that include carbon

compounds, nitrate and sulfate aerosols,

and soil dust. The major cause of

visibility impairment in the eastern

United States is sulfates, while in the

West the other particle types play a

greater role.

XI. Impact on Small Entities

The Regulatory Flexibility Act, 5

U.S.C. 601(a), provides that whenever

an agency is required to publish a

general notice of rulemaking, it must

prepare and make available a regulatory

flexibility analysis (RFA). An RFA is

required only for small entities that are

directly regulated by the rule. See MidTex Electric Cooperative, Inc. v. FERC,

773 F.2d 327 (D.C. Cir. 1985) (agency’s

certification need only consider the

rule’s impact on regulated entities and

not indirect impact on small entities not

regulated); Colorado State Banking Bd.

v. Resolution Trust Corp., 926 F.2d 931

(10th Cir. 1991). This rulemaking

simply requires States to develop,

adopt, and submit SIP revisions, and

does not directly regulate any entities.

Accordingly, pursuant to 5 U.S.C.

605(b), the Administrator certifies that

this rule will not have a significant

economic impact on a substantial

number of small entities. Furthermore,

because affected States will have

discretion to choose which sources to

regulate and how much emissions

reductions each selected source must

achieve, EPA cannot now predict the

effect of this rule on small entities. In

addition, if States adopt the control

measures that form the basis of the

proposed State budget, there will be

little, if any, effect on small businesses.

XII. Unfunded Mandates Reform Act

Title II of the Unfunded Mandates

Reform Act of 1995 (UMRA), Pub. L.

104–4, establishes requirements for

Federal agencies to assess the effects of

their regulatory actions on State, local,

and tribal governments and the private

sector. Under section 202 of the UMRA,

EPA generally must prepare a written

statement, including a cost-benefit

analysis, for proposed and final rules

with ‘‘Federal mandates’’ that may

result in expenditures to State, local,

and tribal governments, in the aggregate,

or to the private sector, of $100 million

or more in any one year. Before

promulgating an EPA rule for which a

written statement is needed, section 205

of the UMRA generally requires EPA to

identify and consider a reasonable

number of regulatory alternatives and

adopt the least costly, most costeffective or least burdensome alternative

that achieves the objectives of the rule.

The provisions of section 205 do not

apply when they are inconsistent with

applicable law. Moreover, section 205

allows EPA to adopt an alternative other

than the least costly, most cost-effective

or least burdensome alternative if the

Administrator publishes with the final

rule an explanation why that alternative

was not adopted. Before EPA establishes

any regulatory requirements that may

significantly or uniquely affect small

governments, including tribal

governments, it must have developed

under section 203 of the UMRA a small

government agency plan. The plan must

provide for notifying potentially

affected small governments, enabling

officials of affected small governments

to have meaningful and timely input in

the development of EPA regulatory

proposals with significant Federal

intergovernmental mandates, and

informing, educating, and advising

small governments on compliance with

the regulatory requirements.

The EPA has determined that this rule

contains a Federal mandate that may

result in expenditures of $100 million or

more for State, local, and tribal

governments, in the aggregate, or the

private sector in any one year.

Accordingly, EPA has prepared under

section 202 of the UMRA a written

statement which is summarized below.

The EPA has determined that to meet

the requirements of section 110(a)(2)(D)

of the Clean Air Act, States must submit

SIP provisions that limit NOX emissions

to the specified amounts indicated

elsewhere in this rulemaking. The EPA

is granting the affected States broad

discretion in developing SIP controls to

attain these levels. The EPA has

examined a variety of possible,

regionwide NOX emissions controls,

which could form the basis for (i) State

budgets of different levels than

proposed, as well as (ii) State packages

of control meadeveloping the budget

levels. The EPA is soliciting comment

on whether the budget levels proposed

in today’s action are the most costeffective or least burdensome alternative

that achieves the objectives of the rule

and on other alternatives (e.g., applying

different levels of control in different

subregions), if feasible, that EPA should

examine in developing final budget

levels.

By today’s proposal, EPA is not

directly establishing any regulatory

requirements that may significantly or

uniquely affect small governments,

including tribal governments. Thus,

EPA is not obligated to develop under

section 203 of the UMRA a small

government agency plan.

Consistent with the intergovernmental

consultation provisions of section 204 of

the UMRA and Executive Order 12875,

‘‘Enhancing the Intergovernmental

Partnership,’’ EPA has already initiated

consultations with the governmental

entities affected by this rule. The EPA

already consulted with these

governmental entities extensively

during the OTAG process. The EPA has

received extensive comments from

governmental entities through OTAG,

including specific recommendations

from OTAG, as described above. The

EPA has evaluated those comments and

recommendations, and has determined
60376 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

1Budget as used in this recommendation does not

imply that a cap will be implemented.

2As described in the Utility NOX Controls

Recommendation.

to propose statewide budget levels

based on a basket of regional NOX

controls that bear some similarity to

those OTAG recommendations. The

EPA’s reasons for doing so are described

at length in this rulemaking.

Dated: October 10, 1997.

Carol M. Browner,

Administrator.

BILLING CODE 6560–50–P

Appendix A—References

1. Ozone Transport Assessment Group

(OTAG), Policy Paper approved by the Policy

Group on December 4, 1995.

2. National Research Council, Committee

on Tropospheric Ozone Formation and

Measurement, ‘‘Rethinking the Ozone

Problem in Urban and Regional Air

Pollution,’’ pp. 93–107, National Academy

Press, Washington, DC, 1991.

3. Wisconsin Department of Natural

Resources, ‘‘An Analysis of Measured and

Predicted Concentrations Aloft of Ozone and

Total Reactive Oxides of Nitrogen in the

Eastern U.S. During July 1995,’’ DRAFT,

January 25, 1997, Madison, WI.

4. Northeast States for Coordinated Air Use

Management, ‘‘The Long-Range Transport of

Ozone and Its Precursors in the Eastern

United States,’’ March 1997, Boston, MA.

5. OTAG, ‘‘Ozone Transport Assessment

Group Modeling Protocol,’’ Version 3.0,

1996.

6. OTAG, ‘‘Ozone Transport Assessment

Group Draft Final Report, Chapter 2 Regional

and Urban Scale Modeling,’’ 1997.

7. Sonoma Technology, Inc., ‘‘Evaluation of

the UAM–V Model Performance in OTAG

Simulations, Phase I: Summary of

Performance Against Surface Observations,’’

January 1997, STI–996120–1605–FR, Santa

Rosa, CA.

8. E.H. Pechan & Associates, ‘‘OTAG

Emissions Inventory Development Report,’’

Volumes I, II, and III: DRAFT Report, June

1997, Durham, NC.

9. OTAG, ‘‘DRAFT Final Report Volume I:

Executive Summary, Ozone Transport

Assessment Group Air Quality and Analysis

Workgroup.’’ June, 1997.

10. Chameides, W.L. and E.B. Cowling,

‘‘The State of the Southern Oxidants Study

(SOS): Policy-Relevant Findings In Ozone

Pollution Research, 1988–1994.’’ pg. 37,

January 1995.

11. Porter, P.S., S.T. Rao, E. Zalewsky, I

Zurbenko, R.F. Henry, and J.Y. Ku,

‘‘Statistical Characteristics of SpectrallyDecomposed Ambient Ozone Time Series

Data,’’ Report to the Ozone Transport

Assessment Group, 1996.

12. Environ, Inc., ‘‘Review of Existing

Ozone Measurement and Modeling Studies

in the Eastern United States,’’ February 21,

1996, Novato, CA.

13. Ozone Transport Commission, ‘‘1994

Fall Meeting Report,’’ September 27, 1994,

Newport, RI.

14. Morris, R.E., G.M. Wilson, S.B.

Shepard, and K. Lee, ‘‘Ozone Source

Apportionment Modeling Using the July

1991 OTAG Episode for the Northeast

Corridor and Lake Michigan Regions,’’ March

1997, Environ, Inc., Novato, CA.

15. McNeill, D., T.W.X. Task,

‘‘Photochemical Modeling Analysis of the

Northwest ‘‘Ozone Free’’ OTAG States Using

the July 1995 OTAG Modeling Episode,’’

March 1997, Alpine Geophysics, Golden, CO.

16. EPA, 1995, ‘‘National Air Pollutant

Emission Trends, 1990–1994,’’ EPA–454/R–

95–001, October 1995.

17. U.S. Environmental Protection Agency,

‘‘Nitrogen Oxides: Impacts on Public Health

and the Environment,’’ EPA–452/R–97–002,

August 1997.

Appendix B—OTAG Recommendations

July 8, 1997.

Ms. Mary Nichols,

Assistant Administrator, Air & Radiation

Division, U.S. Environmental Protection

Agency, 401 M Street, SW., (MC–M6101),

Washington, DC 20460

Dear Ms. Nichols: The Ozone Transport

Assessment Group (OTAG) has completed its

work in accordance with your memorandum

of March 2, 1995. Attached please find the

recommendations to the U.S. Environmental

Protection Agency approved by OTAG. Also

attached are states’ and stakeholders’

comments on the recommendations and

identification of the votes cast on each by

each state. The technical support documents

resulting from OTAG’s work will be

forwarded as soon as they are completed.

We appreciate the technical and financial

support that EPA has provided OTAG over

the past two years. We believe that this

unprecedented effort of dynamic interaction

among state and federal government,

industry and environmental stakeholders has

demonstrated that diverse interests can work

together constructively on important policy

issues. We encourage EPA to consider

OTAG’s recommendations as it proceeds

with implementation of the Clean Air Act.

Sincerely,

Mary A. Gade,

Chair, Policy Group.

Donald R. Schregardus,

Chair, Strategies & Controls Subgroup.

Ned O. Sullivan,

Chair, Outreach & Communications

Subgroup.

Robert C. Shinn, Jr.,

Chair, Modeling & Assessment, Subgroup.

Harold Reheis,

Chair, Financial Subgroup.

Recommendation: Additional Modeling and

Air Quality Analysis (Approved by the

Policy Group, June 3, 1997)

Based on the conclusions of OTAG, states

must have the opportunity to conduct

additional local and subregional modeling

and air quality analyses, as well as develop

and propose appropriate levels and timing of

controls. In taking these actions, priority

should be given to the serious and severe

nonattainment areas of Atlanta, Lake

Michigan, and the Northeast, relative to

transport. EPA has announced its intention to

propose and take final action on a SIP call.

States can work together and with EPA

toward completing local SIPs including the

evaluation of possible local NOX disbenefits,

and to build on the modeling and air quality

analysis work of OTAG to evaluate EPA’s

proposed statewide tonnage budgets 1 in its

proposed SIP calls. The initial statewide

tonnage budgets proposed by EPA may be

revised or shown to be unnecessary or

insufficient through additional subregional

modeling or air quality analyses. OTAG

recommends EPA evaluate states’ timely

submittal of comments and subregional

modeling regarding the proposed statewide

budgets prior to EPA’s finalizing the SIP calls

within 12 months of their proposal.

The Policy Group recognizes that NOX

controls for ozone reduction purposes have

collateral public health and environmental

benefits, including reductions in acid

deposition, eutrophication, nitrification, fine

particle pollution and regional haze.

Recommendation: Diesel Fuel (Approved by

the Policy Group, June 3, 1997)

OTAG recommends that, by 1999, EPA

should evaluate the emission benefits and

other effects, such as fuel economy, of cetane

adjustments on current technology engines,

both on highway and non-road, and, if

appropriate, expeditiously adopt and

implement standards. OTAG further

recommends that the EPA use of existing

collaborative process developed as a result of

the 1995 statement of principles to identify

if new diesel fuel standards are beneficial. If

found beneficial and cost-effective, OTAG

further recommends that EPA adopt and

implement new standards no later than 2004.

Recommendation: Gasoline (Approved by

the Policy Group May 13, 1997)

The OTAG states recommend the

continued use of Federal Reformulated

Gasoline (RFG) in the mandated and opt-in

areas.

The OTAG states support state flexibility

and encourage the opt-in to the Federal RFG

program or other fuel strategies consistent

with the Clean Air Act, including those

attainment areas which contribute to

downwind nonattainment situations or

which choose to implement strategies to

assist in preventing violations of the National

Ambient Air Quality Standard (NAAQS) for

ozone.

The USEPA should adopt and implement

by rule an appropriate sulfur standard to

further reduce emissions and assist the

vehicle technology/fuel system achieve

maximum long term performance.

Recommendation: Vehicle Emission

Inspection and Maintenance Controls

(Approved by the Policy Group, June 19,

1997)

• The OTAG states recommend that, where

required by the Clean Air Act, appropriate

and effective vehicle emission inspection and

maintenance (I/M) programs be

implemented. The OTAG states additionally

recommend that states consider the adoption

of enhanced I/M programs in all urbanized

areas in the fine grid 2 with a population

greater than 500,000.

• The OTAG states further recommend

that EPA recognize and give appropriate
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60377

credit to the state-by-state emission reduction

benefits of vehicle I/M programs and their

impact on transport of ozone and its

precursors.

• The OTAG states recognize the potential

effectiveness of a vehicle on-board diagnostic

(OBD) system to alert drivers of emission

control system malfunctions and to ensure

proper maintenance and operation of the

emission control system under real world

driving conditions. Therefore, they encourage

EPA to support periodic OBD system checks

as part of an effective vehicle I/M program

and to provide appropriate I/M program

credit.

Recommendation: Major Modeling/Air

Quality Conclusions (Approved by the Policy

Group, June 3, 1997)

Based on OTAG modeling, the Regional

and Urban Scale Modeling and Air Quality

Analysis Workgroups have drawn several

conclusions regarding the benefits to be

derived from NOX and VOC controls for all

source sectors and regarding ozone transport.

Regional NOX reductions are effective in

producing ozone benefits; the more NOX

reduced, the greater the benefit. Ozone

benefits are greatest where emission

reductions are made and diminish with

distance. Elevated and low level NOX

reductions are both effective. VOC controls

are effective in reducing ozone locally and

are most advantageous to urban

nonattainment areas. Air quality data

documents the widespread and pervasive

nature of ozone and indicates transport of

ozone. Air quality analyses also indicate that

ozone aloft is carried over and transported

from one day to the next. Generally, the range

of transport is longer in the North than in the

South. Additionally, coarse grid impacts on

the fine grid may be minimal. Other relevant

documentation of the RUSM and AQA

Workgroups’ efforts are available on their

Web sites.

Recommendation: National Measures

(Approved by the Policy Group May 13,

1997)

The OTAG states recommend that the

USEPA continue to develop and

expeditiously adopt, no later than the dates

indicated below, and effectively implement

stringent control measures on a national basis

which meet or exceed the emission reduction

levels as contained in the OTAG analysis.

The measures include:

Measure

Reductions assumed

in the modeling Adoption

date

Start/

implementation date percent 1 Tons 2, 3

Arch & Industrial Maintenance (AIM) Coatings:

—Phase I ................................................................................................ 20% VOC 507 November 97 January 98/

—Phase II ............................................................................................... 38% VOC 861 ...................... 2003.

Consumer/Commercial Products:

—Phase I ................................................................................................ 20% VOC 886 November 97 March 98/

—Phase II ............................................................................................... 30% VOC 1281 ...................... 2003.

Autobody Refinishing:

—Phase I ................................................................................................ 37% VOC 281 August 97 .... January 98/

—Phase II ............................................................................................... 53% VOC 391 ...................... 2003.

Reformulated Gasoline .................................................................................. 25% VOC 4 5 na ...................... 2000.

(RFG) Phase II .............................................................................................. 6.8% NOX na ......................

Phase II Small Engine Standards .................................................................. 43% VOC 1343 ...................... 2007.

Marine Engine Standards .............................................................................. 23% VOC 398 ...................... 1998.

Heavy Duty Highway 2g Standard (Equivalent to a 4g standard in 2007) ... Varies by

Engine

Family

5 na ...................... 2004.

Heavy Duty Nonroad Diesel Standard .......................................................... 37% NOX 1499 ...................... 2004.

Locomotive Standard with Rebuild ................................................................ 43% NOX

10% NOX

6 na

126

...................... 1997.

1Percent reductions were applied to 1990 emissions projected to 2007.

2Tonnage reduction differences are based on 1990 emissions projected to 2007.

3 Reductions from multi-phase programs are cumulative.

4For Phase II RFG, percent reductions are based only on affected emissions.

5Tonnage reductions could not be calculated for RFG and the Heavy Duty Highway 2g Standard since the effects of growth and control could

not be accounted for separately by the model used. 6The 43% reduction includes rebuilt engines; however, rebuilts were not modeled by OTAG. The modeled reduction was only 10%.

• The OTAG states encourage the USEPA

to reach closure on the Tier 2 Motor Vehicle

Study in recognizing the benefits of volatile

organic compound and nitrogen oxide

reductions and their implication for ozone

production.

Recommendation: National Low Emission

Vehicle (Approved by the Policy Group May

13, 1997)

The OTAG states acknowledge the ability

of states to adopt the California Low

Emission Vehicle Program and further

acknowledge that the National Low Emission

Vehicle Program is a voluntary program.

OTAG supports and encourages the

implementation of a National Low Emission

Vehicle Program.

Recommendation: Non-Utility Point Source

Controls (Approved by the Policy Group,

June 19, 1997)

Definitions

For purposes of this recommendation,

individual medium non-utility point sources

are defined as follows:

A boiler > 100 MMBtu/hr and < 250 MMBtu/

hr

A reciprocating i.c. engine > 4000 hp and <

8000 hp

A turbine > 10,000 hp and < 20,000 hp

Any other source > 1 ton/average summer

day and < 2 tons/average summer day

For purposes of this recommendation,

individual large non-utility point sources are

defined as follows:

A boiler ≥ 250 MMBtu/hr

A reciprocating i.c. engine ≥ 8000 hp

A turbine ≥ 20,000 hp

Any other source ≥ 2 tons/average summer

day

Control Levels

The OTAG Policy Group recommends that

the stringency of controls for large non-utility

point sources should be established in a

manner equitably with utility controls. The

OTAG Policy Group recommends that RACT

should be considered for individual medium

non-utility point sources were appropriate.

If additional modeling and air quality

analyses are performed as specified in

OTAG’s recommendation for ‘‘Additional

Modeling and Air Quality Analysis,’’ then

development of final state non-utility point

source strategies should consider said

modeling and analyses.
60378 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

3Budget as used in this recommendation does not

imply that a cap will be implemented.

Control Targets for Budget 3 Calculation

Purposes

The OTAG Policy Group anticipates

USEPA will calculate a statewide NOx

tonnage budget for each state. In calculating

the statewide NOx tonnage budgets, the

OTAG Policy Group recommends a

calculation based on the following nonutility point source control targets:

Reference utility control level

(coal-fired

power plants)

Control

targets

for the

large

non-utility

point

source

sector

(percent)

Control targets

for the medium

non-utility point

source sector

55% (0.35 lb/

MMBtu).

55 Uncontrolled.

65% (0.25 lb/

MMBtu).

60 Uncontrolled.

75% (0.20 lb/

MMBtu).

65 RACT.

85% (0.15 lb/

MMBtu).

70 RACT.

The control targets, expressed as an

emission reduction percentage, should be

based on uncontrolled emission rates. The

budget component for non-utility point

sources is not intended to be an allocation for

the non-utility point source sector or for

individual units.

Flexibility and Relationship to Other

Requirements

The OTAG Policy Group acknowledges

that states have flexibility in implementing

the non-utility point source strategy. These

recommendations shall not supersede any

other more restrictive state or federal

requirement.

Recommendation: Ozone Action Days

(Approved by the Policy Group, June 3,

1997)

The OTAG states endorse and encourage

the development and implementation of

ozone action programs to increase public

awareness of the public health and welfare

issues associated with ozone air pollution.

These include but are not limited to daily

summertime ozone mapping projects which

provide ‘‘real-time’’ information to the

viewer and other programs and information

to encourage participation in programs to

reduce the emissions of ozone precursors.

These programs may be effective in reducing

peak ozone concentrations. They

complement traditional control strategies for

the reduction of ozone and ozone precursors.

Recommendation: OTAG’s Technical

Analysis (Approved by the Policy Group,

June 3, 1997)

OTAG’s goal is to ‘‘identify and

recommend a strategy to reduce transported

ozone and is precursors which, in

combination with other measures, will

enable attainment and maintenance of the

national ambient ozone standard in the

OTAG region.’’ OTAG has performed the

most comprehensive technical analysis of

ozone transport ever conducted. In

cooperation with the states and stakeholders

and by sharing information, OTAG has

developed and produced the best and most

complete emissions inventory for the OTAG

region. OTAG has used UAM–V, a state-ofthe-art photochemical model, to analyze the

potential impact of various control strategies.

OTAG has also developed and applied new

techniques to analyze existing air quality

data to examine the ozone problem.

Recommendation: Trading Program

Framework (Approved by the Policy Group,

June 19, 1997)

Market-based approaches are generally

recognized as having the following benefits

in relation to traditional command and

control regulations: (1) reduce the cost of

compliance; (2) create incentives for early

reductions; (3) create incentives for emission

reductions beyond those required by

regulations; (4) promote innovation; and (5)

increase flexibility without resorting to

waivers, exemptions and other forms of

administrative relief.

OTAG recognizes that states have the

option to select market systems that are best

suited to their policy purposes and air

quality planning and program needs. In

anticipation of the state specific decisions,

OTAG recognizes that states may choose one

of two basic approaches to implement NOx

emissions market systems.

• Track One—States that elect to

implement equivalent NOx market systems

with emissions caps could be part of a

common, interstate emissions market.

Designated sources would be authorized to

participate in emissions trading. Other

stationary sources could opt-in to the market

under specific conditions. A central

regulatory authority, such as EPA, could

administer this multi-state NOx market

system.

• Track Two—States that elect to

implement NOx market systems without

emissions caps would be part of one or more

alternative emissions markets. These

alternative markets could have several

different forms starting with intra-state

emissions trading which could possibly lead

to multi-state trading arrangements.

Participating sources in each state would be

authorized to conduct emissions trading

consistent with the scope of the alternative

market system. If multiple, equivalent NOx

market systems are generated by states, then

some central entity, in consultation with

EPA, could administer the multi-state NOx

market system.

While OTAG recognizes that the

procedures for a cap and trade program are

known and implementable, the OTAG

encourages the joint state/EPA workgroup(s)

described herein to bring similar certainty to

non-cap but SIP approved trading programs.

At some point, states may be interested in

cross-track trading. Further development

work and more time is necessary to

determine whether and how this cross-track

trading could be credibly done.

Implementation of either track should not be

delayed while an approach for cross-track

trading is developed. Inter-sector trading

might be provided for as well.

EPA review and approval of specific state

SIP revisions would be necessary for NOx

market systems from either track that are

developed in response to EPA’s SIP call.

States would be responsible for meeting

applicable federal requirements and ensuring

that the integrity of the state’s emissions

budget was maintained, as well as other

desirable results from adoption to suitable

market systems. EPA is responsible for

approving state programs that meet the

applicable federal requirements.

OTAG also recommends that a joint state/

EPA Workgroup be formed to address, with

appropriate stakeholder involvement, the

following tasks:

• Appropriate provisions for

implementing Tracks One and Two as

described above.

• Key design features for NOx emissions

market systems that could be selected by

affected states.

A series of seven design proposal papers

have been developed by the Trading/

Incentives Workgroup which include specific

recommendations that are incorporated in

the OTAG final report. These papers serve as

a sound basis for carrying out the work of

this joint workgroup. The following specific

issues should also be addressed by the joint

workgroup:

1. Subregional modeling and air quality

analysis should be carefully evaluated to

determine whether distance and direction

should affect how trading may take place.

Appropriate mechanisms, such as trading

ratios or weights, could be developed if

significant effects are expected.

2. Market systems should be operated and

evaluated, and adjustments made as needed

to reflect experience gained with trading

dynamics and any attendant air quality

impacts.

3. Local control requirements necessary for

attainment may still be utilized for specific

sources.

Recommendation: Utility NOX Controls

(Approved by the Policy Group, June 3,

1997)

The OTAG Policy Group recommends that

the range of utility NOX controls in the fine

grid fall between Clean Air Act controls and

the less stringent of 85% reduction from the

1990 rate (lb/mmBTU) or 0.15 lb/mmBTU in

order to mitigate ozone transport and assist

states in complying with the existing 120 ppb

ozone standard. OTAG modeling shows that

ozone transport is greater in the northern tier

than in the southern tier. EPA has indicated

that control levels are to be determined and

implemented through statewide tonnage

budgets. The statewide budget process

should be as described OTAG’s

recommendation ‘‘Additional Modeling and

Air Quality Analysis.’’ Control measures are

to be determined and implemented by the

states. The actions set forth in this section

must be carried out in accordance with the

Clean Air Act. If trading is allowed, public

interest stakeholders have recommended that

a minimum of 10% of each state’s tonnage

budget be allocated solely to qualifying,

verifiable, and new end-use energy efficiency
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60379

4 It is understood that the State of Iowa will work

with the State of Wisconsin in the development of

the Southeast Wisconsin ozone SIP.

5 It is understood that the state of Kansas will

work with the state of Missouri in the continued

progress of the Kansas City ozone SIP. In addition,

the states of Oklahoma, Texas, Arkansas, and

Louisiana will share with the state of Missouri the

results of their urban and regional scale ozone

modeling which includes boundary condition

information and emissions in inventory data

showing projected impacts of ozone control

programs.

and renewable projects. The coarse grid

states which would be exempt from OTAGrelated controls (all of North Dakota, South

Dakota, Nebraska, Kansas, Oklahoma, Texas,

Minnesota, Iowa,4 Arkansas, Louisiana,

Mississippi, and Florida, as well as the

coarse grid portions of Maine, New

Hampshire, Vermont, New York, Michigan,

Wisconsin, Missouri 5, Alabama, and

Georgia) will, in cooperation with EPA,

periodically review their emissions, and the

impact of increases, on downwind

nonattainment areas and, as appropriate, take

steps necessary to reduce such impacts

including appropriate control measures.

Appendix C—Tables for Section II

Weight of Evidence Determination of

Significant Contribution

TABLE II–1.—OTAG 2007 STATE

TOTAL NOX Emissions (tons/day)

State Total

NOX

Texas .............................................. 4026

Ohio ................................................ 2871

Illinois .............................................. 2535

Florida ............................................. 2503

Pennsylvania ................................... 2406

Michigan .......................................... 2334

Indiana ............................................ 2271

Louisiana ......................................... 2143

Tennessee ...................................... 2090

Georgia ........................................... 1711

New York ........................................ 1677

Alabama .......................................... 1621

Kentucky ......................................... 1598

North Carolina ................................. 1506

West Virginia ................................... 1393

Virginia ............................................ 1378

New Jersey ..................................... 1244

Missouri ........................................... 1140

Oklahoma ........................................ 1107

South Carolina ................................ 1040

Wisconsin ........................................ 1035

Mississippi ....................................... 1012

Kansas ............................................ 993

TABLE II–1.—OTAG 2007 STATE

TOTAL NOX Emissions (tons/day)—

Continued

State Total

NOX

Maryland ......................................... 940

Minnesota ....................................... 917

Iowa ................................................ 782

Massachusetts ................................ 701

Arkansas ......................................... 643

Nebraska ......................................... 411

Connecticut ..................................... 362

Maine .............................................. 232

New Hampshire .............................. 192

Delaware ......................................... 164

South Dakota .................................. 140

Vermont .......................................... 78

Rhode Island ................................... 78

North Dakota ................................... 55

District of Columbia ........................ 53

TABLE II–2.—OTAG 2007 STATE NOx

Emissions Density (tons/day/1000

sq. mi.)

State

Emissions

density

District of Columbia ........................ 771.91

New Jersey ..................................... 166.53

Maryland ......................................... 95.55

Massachusetts ................................ 89.62

Delaware ......................................... 85.09

Connecticut ..................................... 74.30

Rhode Island ................................... 73.76

Ohio ................................................ 70.03

Indiana ............................................ 63.19

West Virginia ................................... 57.73

Pennsylvania ................................... 53.58

Tennessee ...................................... 50.79

Louisiana ......................................... 48.14

Florida ............................................. 46.22

Illinois .............................................. 45.56

Michigan .......................................... 40.97

Kentucky ......................................... 40.27

New York ........................................ 35.40

Virginia ............................................ 34.71

South Carolina ................................ 34.43

Alabama .......................................... 31.92

Texas .............................................. 31.42

North Carolina ................................. 30.83

Georgia ........................................... 29.48

Mississippi ....................................... 21.42

New Hampshire .............................. 21.39

Kansas ............................................ 20.85

Oklahoma ........................................ 20.68

Wisconsin ........................................ 19.02

Minnesota ....................................... 18.32

TABLE II–2.—OTAG 2007 STATE NOx

Emissions Density (tons/day/1000

sq. mi.)—Continued

State

Emissions

density

Missouri ........................................... 16.54

Iowa ................................................ 13.97

Nebraska ......................................... 13.43

Arkansas ......................................... 12.09

Vermont .......................................... 8.42

Maine .............................................. 7.49

North Dakota ................................... 7.28

South Dakota .................................. 5.30

TABLE II–3.—OTAG 2007 BASELINE

CONTROL MEASURES

UTILITY

• Title IV Controls (phase 1 & 2 for all boiler types)

• 250 Ton PSD and NSPS

• RACT & NSR in non-waived nonattainment areas (NAAs)

NON-UTILITY POINT/OTHER AREA

• RACT at major sources in non-waivered

NAAs

• 250 Ton PSD and NSPS

• CTG & Non-CTG RACT at major

sources in NAAs & in Ozone Transport

Region

OTHER AREA

• Two Phases of Consumer & Commercial

Products & One Phase of Architectural

Coatings

• Stage 1 & 2 Petroleum Distribution Controls in NAAs

• Autobody, Degreasing & Dry Cleaning

Controls in NAAs

NONROAD MOBILE

• Federal Phase II Small Engine Standards

• Federal Marine Engine Standards

• Federal HDV (>=50 hp) Standards-Ph.1

• Federal RFG II (statutory and opt-in

areas)

• 9.0 RVP maximum elsewhere in OTAG

HIGHWAY MOBILE

• Tier 1 LDV and HDV Standards

• Federal RFG II (statutory and opt-in

areas)

• High Enhanced I/M (serious and above

areas)

• Low Enhanced I/M for rest of OTR

• Basic I/M (mandated areas)

• Clean Fuel Fleets (mandated areas)

• 9.0 RVP maximum elsewhere in OTAG

• On board vapor recovery
60380 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–4a.—OTAG STRATEGY CONTROL PACKETS FOR NOX

NOX strategy packets Utility system

[Mostly elevated]

Other point/area

[Mixed Elevated & Non-elevated]

Nonroad Mobile

[Non-elevated]

Highway Mobile

[Non-elevated]

Base 1 (Mandated

CAA controls).

*Title IV Controls [Phase 1

& 2 for all boiler types]

*250 Ton PSD and NSPS

*RACT & NSR in nonwaived NAAs

*RACT at major sources in

non-waivered NAAs

*250 Ton PSD and NSPS

*NSR in non-waived NAAs

*Fed Phase II Small Eng.

Stds

*Fed Marine Engine Stds

*Fed HDV (>=50 hp) StdsPhase 1

*Fed RFG II 4

*Tier 1 LDV and HDV Stds

*Fed RFG II 4

*Enh I/M 3

*Low Enh I/M for rest of

OTR

*Basic I/M in mandated

areas

*Clean Fuel Fleets for mandated areas

Level 0 ........................ Base 1 plus:

*OTC NOX MOU (Phase II)

* ‘‘9% by 99’’ ROP Measures (If substitute for

VOC) 3

Base 1 plus:

*‘‘9% by 99’’ ROP Measures (If substitute for

VOC) 3

Base 1 plus:

*Fed Locomotive Standards

(not including rebuilds)

*‘‘9% by 99’’ ROP Measures (If substitute for

VOC) 3

Base 1 plus:

*National LEV

*HDV 2 gm std

*FTP revisions

*‘‘9% by 99’’ ROP Measures (If substitute for

VOC) 3

Added NOX Controls—

Level 1.

More stringent of Level 0

or:

*55% reduction from 1990

rate or

*rate-base of 0.35 lb/mmbtu

for coal units and 0.20 lb/

mmbtu for gas & oil units,

whichever is less stringent 7

Level 0 plus:

Controls rated by OTAG as

under $1000 per ton

Level 0 plus:

*Fed Locomotive Stds (incl

rebuild standards) 1 [Replaces Fed Locomotive

Stds (not including rebuilds)]

*HD engine 4 gm Std

Level 0 plus:

*High Enh I/M for LDV

(LEV-specific cutpoints) 6

[Replaces Enh I/M 3, Low

Enh I/M for rest of OTR,

& Basic I/M in mandated

areas]

*HDV I/M 6

Added NOX Controls—

Level 2.

More stringent of Level 0

or:

(a) *65% reduction from

1990 rate or

*rate-base of 0.25 lb/mmbtu

for coal units and 0.20 lb/

mmbtu for gas & oil units,

whichever is less stringent 7

Level 1 plus:

Controls rated by OTAG as

$1000 to $5000 per ton

Level 1 plus:

*Reformed Diesel (50 cetane) 2

Level 1 plus:

*Fed RFG II 2 5 [Replaces

Fed RFG II 4] or Low Sulfur Fuel (150 ppm) 2,5

*Reformed Diesel (50 cetane) 2

*Max I/M for LDV w/ LEVspecified cutpoints 6 [Replaces High Enh I/M for

LDV (LEV-specific

cutpoints).6]

Added NOX Controls—

Level 2.

More stringent of Level 0

or:

(b)* 75% reduction from

1990 rate or

*rate-base of 0.20 lb/mmbtu

for all units, whichever is

less stringent 7

Deep NOX Controls—

Level 3.

More stringent of Level 0

or:

*85% reduction from 1990

rate or

*rate-base of 0.15 lb/mmbtu

for all units, whichever is

less stringent 7

Level 2 plus:

Controls rated by OTAG as

over $5000 per ton

Level 2 plus:

*Reformed Diesel (55 cetane) 2 8 [Replaces Reformed Diesel (50 cetane) 2]

Level 2 plus:

*Cal RFG II 2 [Replaces

Fed FG II 2,5]

*Reformed Diesel (55 cetane) 2 8 [Replaces Reformed Diesel (50 cetane) 2].

1 National.

2OTAG Wide or Specified.

3Serious and above areas.

4Statutory and opt-in areas.

5OTAG-Optimized fuel (e.g., low RVP, low sulfur, low olefins) was evaluated elsewhere during OTAG as an alternative.

6For all nonattainment areas & attainment MSAs/CMSAs ≤=100,000. 7Qualifications set by OTAG on the use of lb/MMBtu numbers:

(1) These numbers are for initial strategy modeling purposes only. They do not reflect any recommendation form OTAG on the desired level of

reduction for these units. (2) OTAG reserves the right to do sensitivity analyses on any source in an effort to achieve a desired ozone impact.

Such sources may include those that chose the lb/MMBtu option. The requirement for such analyses may exist in certain areas where the size

and location of such a major source is critical to achieving the ozone goals. (3) The alternative lb/MMBtu limits shall not supersede an existing

requirement that is more stringent (e.g., OTC MOU or NSPS requirements). 8OTAG evaluated California diesel separately.
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60381

TABLE II–4b.—OTAG STRATEGY CONTROL PACKETS FOR VOC

VOC strategy packets Major point sources Other point/area Nonroad mobile Highway mobile

Base 1 (Mandated

CAA controls).

*CTG & Non-CTG RACT at

major sources in NAAs &

in OTC.

*New Source LAER & Offsets for NAAs.

*Two Phases of Consumer

& Commercial Products &

one Phase of Architectural Coatings.

*Stage 1 & 2 Petroleum

Distribution ControlsNAAs.

*Autobody, Degreasing &

Dry Cleaning Controls in

NAAs.

*Fed Phase II Small Eng.

Stds.

*Fed Marine Engine Stds ...

*Fed HDV (>=50 hp) StdsPh. 1.

*Fed RFG II4 4 ....................

*9.0 RVP maximum elsewhere in OTAG.

*Tier 1 LDV and HDV Stds.

*Fed RFG II 4

*9.0 RVP maximum elsewhere in OTAG.

*Enh I/M.3

*Low Enh I/M for rest of

OTR.

*Basic I/M in mandated

areas.

*Clean Fuel Fleets in mandated areas.

*On board vapor recovery.

Level 0 ........................ Base 1 plus:

*‘‘9% by 99’’ ROP Measures (NOX may be substituted after 1996).3.

Base 1 plus:

*‘‘9% by 99’’ ROP Measures (NOX may be substituted after 1996).3.

Base 1 plus:

*Fed Locomotive Standards

(not including rebuilds).

*‘‘9% by 99’’ ROP Measures (NOX may be substituted after 1996).3.

Base 1 plus:

*National LEV.

*HDV 2 gm std.

*FTP revisions.

*‘‘9% by 99’’ ROP Measures (NOX may be substituted after 1996).3

Added VOC ControlsLevel 1.Level 0 plus: (No additional

controls).

Level 0 plus: (No additional

controls).

Level 0 plus: Level 0 plus:

*High Enh I/M for LDV

(LEV-specific cutpoints) 6

[Replaces Enh I/M 3, Low

Enh I/M for rest of OTR,

& Basic I/M in mandated

areas].

*HDV I/M.6

*Low RVP (6.7 psi) in nonRFG areas 2 [Replaces

9.0 RVP maximum elsewhere in OTAG].

Added VOC ControlsLevel 2.Level 1 plus:

(a) * Apply NAA Base 1 default control assumptions

across AA down to 100

TPY sources.

Level 1 plus:

(a) * Apply NAA Base 1 default control assumptions

across AA down to 100

TPY sources—Bulk Terminals.

Level 1 plus:

*Fed RFG II 2 5 [Replaces

Fed RFG II 4].

Level 1 plus:

*Maximum I/M (LEV-specific cutpoints) for LDV6

[Replaces High Enh I/M

(LEV-specific

cutpoints) 3].

*Fed RFG II 2 5 [Replaces

Fed RFG II 4].

Level 2a plus:

(b) *10% reduction in VOC

emissions beyond level

2a from major point

sources in major metropolitan NAAs.

Level 2a plus:

(b) *Increased C/C Products limits.

*Increased AIM limits ..........

*Increased Autobody Refinishing limits.

.............................................

Deep VOC ControlsLevel 3.Level 2 plus: (Same as 2b) Level 2 plus: (Same as 2b) Level 2 plus:

*Cal RFG II 2 [Replaces

Fed RFG II 2 5].

*Cal Tier II small engine std

Level 2 plus:

*Cal RFG II 2 [Replaces

Fed RFG II 2 5].

1 National.

2OTAG Wide or Specified.

3Serious and above areas.

4Statutory and opt-in areas.

5OTAG-Optimized fuel (e.g., low RVP, low sulfur, low olefins) was evaluated elsewhere during OTAG as an alternative.

6For all nonattainment areas & attainment MSAs/CMSAs >=100,000.

TABLE II–5a.—ROUND 1 AND 2 CONTROL LEVELS BY EMISSIONS SECTOR

OTAG round 1 & round 2 control levels

Run

Point

Nonroad Other area Motor vehicle1

Utility NOX

Nonutility

NOX VOC NOX VOC NOX VOC NOX VOC

Round 1:

1 ...................................... 0 0 0 0 0 0 0 0 0

2 ...................................... 3 3 3 3 3 3 3 3 3

3 ...................................... 3 0 0 0 0 0 0 0 0

4b .................................... 0 3 0 3 3 3 3 3 3
60382 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–5a.—ROUND 1 AND 2 CONTROL LEVELS BY EMISSIONS SECTOR—Continued

OTAG round 1 & round 2 control levels

Run

Point

Nonroad Other area Motor vehicle1

Utility NOX

Nonutility

NOX VOC NOX VOC NOX VOC NOX VOC

Round 2:

5 ...................................... 3 1 0 1 1 1 1 0 0

6 ...................................... 2b 1 0 1 1 1 1 0 0

7 ...................................... 2a 1 0 1 1 1 1 0 0

8 ...................................... 1 1 0 1 1 1 1 0 0

9 ...................................... 3 2 0 2 2 2 2 1.5 1.5

10 .................................... 2b 2 0 2 2 2 2 1.5 1.5

11 .................................... 2a 2 0 2 2 2 2 1.5 1.5

12 .................................... 1 2 0 2 2 2 2 1.5 1.5

1 Motor vehicle emissions level 1.5 includes enhanced I/M in all 1-hr nonattainment areas and in all attainment Metropolitan Statistical Areas

and Consolidated Metropolitan Statistical Areas with population >=500,000.

TABLE II–5b.—DOMAINWIDE ROUND 1 AND 2 EMISSION TOTALS BY SECTOR

Emissions totals (tons/day)

Run

Point

Nonroad Other Area Motor vehicle Total

Utility

NOX

Nonutility

NOX VOC NOX VOC NOX VOC NOX VOC NOX VOC

Round 1:

1990 ...................... 20144 8600 8340 7390 6500 3500 18300 16619 15731 56253 48871

Base1b .................. 14500 10330 5557 7427 6027 4460 17692 14000 9400 50717 38676

1 ............................ 13970 10215 5557 7315 6027 4460 17637 12400 8700 48360 37921

2 ............................ 5203 4969 4217 5725 5854 4460 16912 9200 4500 29557 31483

3 ............................ 5203 9626 5557 7315 6027 4460 17637 12400 8700 39004 37921

4b .......................... 13946 5562 5557 5725 5854 4460 16912 9200 4500 38893 32823

Round 2:

1990 ...................... 21019 7709 8304 7567 6541 3238 17806 16619 15731 56152 48382

Base1c .................. 15441 8459 5719 7506 6039 4202 17076 14000 9400 49608 38234

5 ............................ 5348 6828 5712 6453 6039 4202 17076 12400 8700 35231 37527

6 ............................ 7383 6828 5712 6453 6039 4202 17076 12400 8700 37266 37527

7 ............................ 9249 6828 5712 6453 6039 4202 17076 12400 8700 39132 37527

8 ............................ 11425 6828 5712 6453 6039 4202 17076 12400 8700 41308 37527

9 ............................ 5348 5247 5712 6381 5989 4202 15757 10650 5500 31828 32958

10 .......................... 7383 5247 5712 6381 5989 4202 15757 10650 5500 33863 32958

11 .......................... 9249 5247 5712 6381 5989 4202 15757 10650 5500 35729 32958

12 .......................... 11425 5247 5712 6381 5989 4202 15757 10650 5500 37905 32958
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60383

TABLE II–6.—RESULTS OF ROUND 1 AND ROUND 2 STRATEGY MODELING

Round-1 Results:

Run 1 (Level 0)

—Little additional benefit on regional scale

—Benefits occur mostly in Northeast

Run 2 (Level 3)

—Large areas of lower ozone; decreases of 10–40 ppb

—Level 3 control will not provide for attainment throughout the eastern U.S.

Run 3 (Level 3 Elevated NOX) and Run 4b (Level 3 Low-Level NOX)

—Both elevated and low-level control effective in lowering ozone on regional scale

—Relative effectiveness varies by region and episode (e.g., elevated [utility] NOX more effective in Midwest, low-level NOX more effective

in Northeast and Southeast)

All Strategies

—For all strategies, there are ozone increases in some areas on some days

—For all strategies, the 8-hour concentration changes are directionally consistent with the 1-hour concentration changes

Round-2 Results:

The Round-2 strategy emission/ozone reductions are all within the range of Run 1 (Round-1) and Run 2 (Round-1)

—More emissions reductions, more ozone reductions

—Run 9 (maximum Round-2 emissions reduction) provides a little less ozone benefit than Run 2

—Run 9 will not be sufficient to provide for attainment of the current 1-hour ozone NAAQS throughout the Eastern U.S.

—Elevated and low-level NOX reductions are both effective in lowering ozone (relative effectiveness varies by episode)

—Elevated and low-level NOX reductions are cumulative, but may not be synergistic (i.e., appear to act independently)

—Run 8 (minimum Round-2 emissions reduction) show ozone increases in some areas on some days; note, increases do not seem to get

any worse by Run 9 (maximum Round-2 emissions reduction)

—All Round-2 strategies show ozone decrease in areas and on days with high ozone, and ozone increases in areas and on days with low

ozone

—Magnitude and spatial extent of 8-hour concentration differences are similar to 1-hour concentration differences

TABLE II–7.—ROUND 3 CONTROL LEVELS BY GEOGRAPHIC ZONE 1

Source category Control level

Nonroad/Area Sources ....... Level 2.

Point Source VOC .............. Level 0.

Highway Vehicles ............... Level 1.3 (same as Level 2, except high enhanced I/M is applied to all nonattainment areas and attainment Metropolitan Statistical Areas/Consolidated Metropolitan Statistical Areas with population >= 500,000 in the ‘‘Fine

Grid’’ portion of the OTAG region only)

Non-utility point source

NOX

Linked to the level of utility controls

Utility Non-Utility

Level 0 or ......................................................................... Level 1 for sources >250 MMBtu/hr.

Level 1 ............................................................................. Level 0 for sources <250 MMBtu/hr.

Level 2a ........................................................................... Level 1.

Level 2b or ....................................................................... Level 2 for sources >250 MMBtu/hr.

Level 3 ............................................................................. Level 1 for sources <250 MMBtu/hr.

1The control levels for nonroad sources, area sources, point source VOC, and highway vehicles were applied throughout the OTAG region in

all of the Round 3 runs. Utility and non-utility NOx control levels varied geographically.

TABLE II–7.—(CONTINUED)

Round 3 utility control levels

Run #

Chicago/Atlanta/Northeast NAAs

Zone III NortheastZone I MidwestZone V N.

Georgia

Zone II Ohio

Valley

Zone IV

Southeast Coarse grid Utility NOXemissions

A ................... 2b .................. 1 .................... 1 .................... 1 .................... 1 .................... 1 .................... 0 1,822,915

B ................... 2a .................. 2a .................. 2a .................. 2a .................. 1 .................... 1 .................... 0 1,767,341

C .................. 2b .................. 2b .................. 2b .................. 2b .................. 1 .................... 1 .................... 0 1,678,866

D .................. 2b .................. 2b .................. 2b .................. 2b .................. 2a .................. 1 .................... 0 1,581,554

E ................... 2b .................. 2b .................. 2b .................. 2b .................. 2a .................. 2a .................. 0 1,528,004

F ................... 2a/2b ............. 2b .................. 2a .................. 2a .................. 2a .................. 2a .................. 0 1,595,237

G .................. 2b .................. 2b .................. 2b .................. 2b .................. 2b .................. 2a .................. 0 1,433,002

H .................. 2b .................. 2b .................. 2b .................. 2b .................. 2b .................. 2b .................. 0 1,392,877

I1 .................. 3 .................... 3 .................... 3 .................... 3 .................... 3 .................... 2b .................. 0 1,199,268

I .................... 3 .................... 3 .................... 3 .................... 3 .................... 3 .................... 2b .................. 1 1,019,578

Level 0—OTC MOU Phase II/Acid Rain.

Level 1—0.35 lb/MMBtu or 55% rate reduction from 1990.

Level 2a—0.25 lb/MMBtu or 65% rate reduction from 1990.

Level 2b—0.20 lb/MMBtu or 75% rate reduction from 1990.

Level 3—0.15 lb/MMBtu or 85% rate reduction from 1990.
60384 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–8a.—COUNTIES VIOLATING

THE 1-HR OZONE NAAQS BASED

ON 1993–1995 AMBIENT AIR QUALITY MONITORING DATA

State County

Alabama .................... Jefferson.

Alabama .................... Shelby.

Connecticut ............... Hartford.

Connecticut ............... New Haven.

Connecticut ............... Middlesex.

Connecticut ............... Litchfield.

Connecticut ............... New London.

Connecticut ............... Fairfield.

Connecticut ............... Tolland.

Delaware ................... New Castle.

Delaware ................... Kent.

District of Columbia ... Washington.

Georgia ..................... Rockdale.

Georgia ..................... Douglas.

Georgia ..................... De Kalb.

Georgia ..................... Fulton.

Illinois ........................ Cook.

Illinois ........................ Madison.

Indiana ...................... La Porte.

Indiana ...................... Warrick.

Indiana ...................... Clark.

Louisiana ................... Lafourche.

Louisiana ................... Ascension.

Louisiana ................... Iberville.

Louisiana ................... East Baton Rouge.

Maine ........................ York.

Maine ........................ Sagadahoc.

Maryland ................... Prince Georges.

Maryland ................... Anne Arundel.

Maryland ................... Harford.

Maryland ................... Cecil.

Maryland ................... Baltimore City.

Maryland ................... Baltimore.

Massachusetts .......... Worcester.

Massachusetts .......... Middlesex.

Massachusetts .......... Hampden.

Massachusetts .......... Hampshire.

Michigan .................... Allegan.

Michigan .................... Macomb.

Michigan .................... St Clair.

Michigan .................... Mason.

Michigan .................... Muskegon.

Missouri ..................... St Louis.

Missouri ..................... Clay.

Missouri ..................... St Charles.

Missouri ..................... Jefferson.

New Hampshire ........ Rockingham.

New Jersey ............... Camden.

New Jersey ............... Monmouth.

New Jersey ............... Middlesex.

New Jersey ............... Ocean.

New Jersey ............... Mercer.

New Jersey ............... Hudson.

New Jersey ............... Gloucester.

New York .................. Westchester.

New York .................. Putnam.

New York .................. Suffolk.

New York .................. Queens.

New York .................. Kings.

New York .................. Richmond.

Ohio ........................... Warren.

Pennsylvania ............. Philadelphia.

Pennsylvania ............. Montgomery.

Pennsylvania ............. Bucks.

Pennsylvania ............. Delaware.

Pennsylvania ............. Allegheny.

Rhode Island ............. Kent.

Rhode Island ............. Providence.

TABLE II–8a.—COUNTIES VIOLATING

THE 1-HR OZONE NAAQS BASED

ON 1993–1995 AMBIENT AIR QUALITY MONITORING DATA—Continued

State County

Tennessee ................ Shelby.

Texas ........................ Jefferson.

Texas ........................ Harris.

Texas ........................ Gregg.

Texas ........................ Dallas.

Texas ........................ Galveston.

Texas ........................ Brazoria.

Texas ........................ Tarrant.

Texas ........................ Collin.

Texas ........................ Denton.

Virginia ...................... Arlington.

Virginia ...................... Fairfax.

Wisconsin .................. Manitowoc.

Wisconsin .................. Ozaukee.

Wisconsin .................. Milwaukee.

Wisconsin .................. Kenosha.

TABLE II–8b.—COUNTIES VIOLATING

THE 8-HR OZONE NAAQS BASED

ON 1993–1995 AMBIENT AIR QUALITY MONITORING DATA

Alabama .................... Clay.

Alabama .................... Shelby.

Alabama .................... Madison.

Alabama .................... Jefferson.

Arkansas ................... Crittenden.

Connecticut ............... New London.

Connecticut ............... Tolland.

Connecticut ............... New Haven.

Connecticut ............... Hartford.

Connecticut ............... Middlesex.

Connecticut ............... Litchfield.

Connecticut ............... Fairfield.

Delaware ................... New Castle.

Delaware ................... Kent.

Delaware ................... Sussex.

District of Columbia ... Washington.

Florida ....................... Escambia.

Georgia ..................... Rockdale.

Georgia ..................... Fulton.

Georgia ..................... Gwinnett.

Georgia ..................... De Kalb.

Georgia ..................... Douglas.

Georgia ..................... Richmond.

Illinois ........................ Madison.

Illinois ........................ Cook.

Illinois ........................ Kane.

Illinois ........................ Lake.

Indiana ...................... Porter.

Indiana ...................... Hancock.

Indiana ...................... Marion.

Indiana ...................... La Porte.

Indiana ...................... Vanderburgh.

Indiana ...................... Floyd.

Indiana ...................... Lake.

Indiana ...................... Hamilton.

Indiana ...................... Allen.

Indiana ...................... Warrick.

Indiana ...................... Tippecanoe.

Indiana ...................... Clark.

Indiana ...................... Madison.

Indiana ...................... Kosciusko.

Indiana ...................... St Joseph.

Kentucky ................... Fayette.

TABLE II–8b.—COUNTIES VIOLATING

THE 8-HR OZONE NAAQS BASED

ON 1993–1995 AMBIENT AIR QUALITY MONITORING DATA—Continued

Kentucky ................... Greenup.

Kentucky ................... Hancock.

Kentucky ................... Livingston.

Kentucky ................... Campbell.

Kentucky ................... Christian.

Kentucky ................... Lawrence.

Kentucky ................... Scott.

Kentucky ................... Oldham.

Kentucky ................... Boyd.

Kentucky ................... Henderson.

Kentucky ................... Jefferson.

Kentucky ................... Kenton.

Kentucky ................... Bullitt.

Kentucky ................... Daviess.

Kentucky ................... McLean.

Kentucky ................... Hardin.

Louisiana ................... Calcasieu.

Louisiana ................... Livingston.

Louisiana ................... Ascension.

Louisiana ................... Iberville.

Louisiana ................... Lafayette.

Louisiana ................... East Baton Rouge.

Louisiana ................... Lafourche.

Maine ........................ Knox.

Maine ........................ Sagadahoc.

Maine ........................ York.

Maine ........................ Cumberland.

Maryland ................... Kent.

Maryland ................... Baltimore City.

Maryland ................... Charles.

Maryland ................... Prince Georges.

Maryland ................... Anne Arundel.

Maryland ................... Montgomery.

Maryland ................... Baltimore.

Maryland ................... Cecil.

Maryland ................... Harford.

Maryland ................... Carroll.

Massachusetts .......... Middlesex.

Massachusetts .......... Barnstable.

Massachusetts .......... Hampden.

Massachusetts .......... Hampshire.

Massachusetts .......... Essex.

Massachusetts .......... Bristol.

Massachusetts .......... Worcester.

Michigan .................... Benzie.

Michigan .................... Berrien.

Michigan .................... Kent.

Michigan .................... Macomb.

Michigan .................... Cass.

Michigan .................... Muskegon.

Michigan .................... Wayne.

Michigan .................... Mason.

Michigan .................... Lenawee.

Michigan .................... Allegan.

Michigan .................... St Clair.

Mississippi ................. Hancock.

Missouri ..................... St Charles.

Missouri ..................... St Louis.

Missouri ..................... Clay.

Missouri ..................... Jefferson.

New Hampshire ........ Rockingham.

New Hampshire ........ Hillsborough.

New Jersey ............... Camden.

New Jersey ............... Mercer.

New Jersey ............... Gloucester.

New Jersey ............... Hudson.

New Jersey ............... Ocean.

New Jersey ............... Atlantic.
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60385

TABLE II–8b.—COUNTIES VIOLATING

THE 8-HR OZONE NAAQS BASED

ON 1993–1995 AMBIENT AIR QUALITY MONITORING DATA—Continued

New Jersey ............... Morris.

New Jersey ............... Middlesex.

New Jersey ............... Bergen.

New Jersey ............... Hunterdon.

New Jersey ............... Monmouth.

New Jersey ............... Union.

New Jersey ............... Cumberland.

New Jersey ............... Essex.

New York .................. Dutchess.

New York .................. Essex.

New York .................. Richmond.

New York .................. Orange.

New York .................. Queens.

New York .................. Putnam.

New York .................. Niagara.

New York .................. Kings.

New York .................. Suffolk.

New York .................. Jefferson.

New York .................. Westchester.

New York .................. Bronx.

New York .................. Wayne.

North Carolina ........... Wake.

North Carolina ........... Northampton.

North Carolina ........... Lincoln.

North Carolina ........... Haywood.

North Carolina ........... Granville.

North Carolina ........... Guilford.

North Carolina ........... Yancey.

North Carolina ........... Forsyth.

North Carolina ........... Caswell.

North Carolina ........... Franklin.

North Carolina ........... Chatham.

North Carolina ........... Cumberland.

North Carolina ........... Durham.

North Carolina ........... Rowan.

North Carolina ........... Mecklenburg.

North Carolina ........... Johnston.

Ohio ........................... Lawrence.

Ohio ........................... Franklin.

Ohio ........................... Logan.

Ohio ........................... Hamilton.

Ohio ........................... Jefferson.

Ohio ........................... Medina.

Ohio ........................... Portage.

Ohio ........................... Summit.

Ohio ........................... Mahoning.

TABLE II–8b.—COUNTIES VIOLATING

THE 8-HR OZONE NAAQS BASED

ON 1993–1995 AMBIENT AIR QUALITY MONITORING DATA—Continued

Ohio ........................... Clermont.

Ohio ........................... Cuyahoga.

Ohio ........................... Trumbull.

Ohio ........................... Ashtabula.

Ohio ........................... Knox.

Ohio ........................... Madison.

Ohio ........................... Lake.

Ohio ........................... Allen.

Ohio ........................... Washington.

Ohio ........................... Clinton.

Ohio ........................... Licking.

Ohio ........................... Stark.

Ohio ........................... Lucas.

Ohio ........................... Clark.

Ohio ........................... Butler.

Ohio ........................... Montgomery.

Ohio ........................... Warren.

Oklahoma .................. Tulsa.

Pennsylvania ............. Washington.

Pennsylvania ............. Erie.

Pennsylvania ............. Philadelphia.

Pennsylvania ............. Bucks.

Pennsylvania ............. Northampton.

Pennsylvania ............. Lehigh.

Pennsylvania ............. York.

Pennsylvania ............. Beaver.

Pennsylvania ............. Allegheny.

Pennsylvania ............. Blair.

Pennsylvania ............. Lancaster.

Pennsylvania ............. Cambria.

Pennsylvania ............. Delaware.

Pennsylvania ............. Luzerne.

Pennsylvania ............. Berks.

Pennsylvania ............. Perry.

Pennsylvania ............. Mercer.

Pennsylvania ............. Lackawanna.

Pennsylvania ............. Westmoreland.

Pennsylvania ............. Dauphin.

Pennsylvania ............. Montgomery.

Rhode Island ............. Kent.

Rhode Island Providence

South Carolina .......... Richland.

South Carolina .......... Anderson.

South Carolina .......... Chester.

South Carolina .......... York.

Tennessee ................ Blount.

TABLE II–8b.—COUNTIES VIOLATING

THE 8-HR OZONE NAAQS BASED

ON 1993–1995 AMBIENT AIR QUALITY MONITORING DATA—Continued

Tennessee ................ Hamilton.

Tennessee ................ Sullivan.

Tennessee ................ Dickson.

Tennessee ................ Sevier.

Tennessee ................ Sumner.

Tennessee ................ Knox.

Tennessee ................ Shelby.

Tennessee ................ Williamson.

Tennessee ................ Madison.

Tennessee ................ Anderson.

Tennessee ................ Jefferson.

Texas ........................ Harris.

Texas ........................ Smith.

Texas ........................ Jefferson.

Texas ........................ Brazoria.

Texas ........................ Orange.

Texas ........................ Tarrant.

Texas ........................ Dallas.

Texas ........................ Galveston.

Texas ........................ Denton.

Texas ........................ Gregg.

Texas ........................ Collin.

Virginia ...................... Caroline.

Virginia ...................... Hanover.

Virginia ...................... Fairfax.

Virginia ...................... Chesterfield.

Virginia ...................... Prince William.

Virginia ...................... Alexandria City.

Virginia ...................... Arlington.

Virginia ...................... Hampton City.

Virginia ...................... Henrico.

Virginia ...................... Charles City.

Virginia ...................... Suffolk City.

Virginia ...................... Stafford.

West Virginia ............. Cabell.

West Virginia ............. Wood.

Wisconsin .................. Racine.

Wisconsin .................. Outagamie.

Wisconsin .................. Ozaukee.

Wisconsin .................. Sheboygan.

Wisconsin .................. Milwaukee.

Wisconsin .................. Kewaunee.

Wisconsin .................. Kenosha.

Wisconsin .................. Door.

Wisconsin .................. Manitowoc.

TABLE II–9a.—SUMMARY OF AIR QUALITY CONTRIBUTIONS TO DOWNWIND NONATTAINMENT, FOR SUBREGIONS 1–6.

Approach 1 Approach 2 Approach 3 Approach 4

1 hr-violating co. 1 Hr-all grid cells 8 hr-violating co. 8 Hr-all grid cells

No.

impacts No. States No.impacts No. States No.impacts No. States No.impacts No. States

SubRegion 1:

2–5 ppb ...................... 70 4 102 7 80 8 180 10

5–10 ppb .................... 0 0 14 2 21 2 29 3

10–15 ppb .................. 0 0 0 0 1 1 5 1

15–20 ppb .................. 0 0 0 0 6 1 11 1

20–25 ppb .................. 0 0 0 0 5 1 10 1

>25 ppb ...................... 0 0 0 0 1 1 1 1

SubRegion 2:

2–5 ppb ...................... 193 8 362 14 239 16 432 16

5–10 ppb .................... 38 5 93 9 37 5 101 6

10–15 ppb .................. 0 0 23 6 10 2 15 2

15–20 ppb .................. 0 0 6 2 2 1 6 2
60386 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–9a.—SUMMARY OF AIR QUALITY CONTRIBUTIONS TO DOWNWIND NONATTAINMENT, FOR SUBREGIONS 1–6.—

Continued

Approach 1 Approach 2 Approach 3 Approach 4

1 hr-violating co. 1 Hr-all grid cells 8 hr-violating co. 8 Hr-all grid cells

No.

impacts No. States No.impacts No. States No.impacts No. States No.impacts No. States

20–25 ppb .................. 0 0 1 1 5 1 6 2

>25 ppb ...................... 0 0 0 0 1 1 1 1

SubRegion 3:

2–5 ppb ...................... 176 9 484 10 206 9 527 10

5–10 ppb .................... 187 7 376 10 146 9 236 11

10–15 ppb .................. 67 4 180 7 45 3 69 5

15–20 ppb .................. 27 3 42 4 11 1 14 3

20–25 ppb .................. 5 1 9 3 0 0 0 0

>25 ppb ...................... 3 1 21 3 0 0 0 0

SubRegion 4:

2–5 ppb ...................... 10 3 41 5 2 1 3 1

5–10 ppb .................... 12 3 32 3 37 3 84 3

10–15 ppb .................. 30 3 82 3 28 3 91 3

15–20 ppb .................. 7 2 51 3 22 3 46 4

20–25 ppb .................. 4 2 11 2 11 2 19 2

>25 ppb ...................... 37 3 121 3 25 2 29 2

SubRegion 5:

2–5 ppb ...................... 51 7 131 10 181 13 493 14

5–10 ppb .................... 6 2 42 4 150 6 283 8

10–15 ppb .................. 8 3 16 3 12 2 23 2

15–20 ppb .................. 3 2 5 2 0 0 0 0

20–25 ppb .................. 0 0 5 1 0 0 0 0

>25 ppb ...................... 0 0 0 0 0 0 0 0

SubRegion 6:

2–5 ppb ...................... 85 6 236 13 343 13 523 13

5–10 ppb .................... 122 8 215 10 161 10 281 10

10–15 ppb .................. 25 4 63 6 46 3 120 5

15–20 ppb .................. 2 1 11 3 10 1 29 2

20–25 ppb .................. 0 0 2 2 8 2 14 2

>25 ppb ...................... 4 1 17 3 1 1 2 2

TABLE II–9b. SUMMARY OF AIR QUALITY CONTRIBUTIONS TO DOWNWIND NONATTAINMENT, FOR SUBREGIONS 7–12

Approach 1 Approach 2 Approach 3 Approach 4

1 Hr-violating co. 1 Hr-all grid cells 8 Hr-violating co. 8 Hr-all grid cells

Number impactsNumber

States

Number impactsNumber

States

Number impactsNumber

States

Number impactsNumber

States

SubRegion 7:

2–5 ppb ...................... 114 6 249 12 178 9 315 10

5–10 ppb .................... 113 4 211 8 154 7 233 7

10–15 ppb .................. 50 4 90 6 52 4 87 4

15–20 ppb .................. 21 4 47 4 15 2 35 2

20–25 ppb .................. 8 2 20 2 8 1 12 1

> 25 ppb ..................... 19 2 65 2 8 1 35 1

SubRegion 8:

2–5 ppb ...................... 28 5 135 12 89 10 265 12

5–10 ppb .................... 0 0 56 7 19 3 133 4

10–15 ppb .................. 0 0 75 5 8 3 41 3

15–20 ppb .................. 1 1 60 4 1 1 21 1

20–25 ppb .................. 0 0 9 2 0 0 6 1

> 25 ppb ..................... 0 0 3 1 0 0 0 0

SubRegion 9:

2–5 ppb ...................... 11 2 140 9 161 10 340 12

5–10 ppb .................... 4 3 68 7 69 6 197 6

10–15 ppb .................. 4 1 11 2 27 2 67 3

15–20 ppb .................. 0 0 6 1 2 1 8 1

20–25 ppb .................. 0 0 4 1 0 0 2 1

> 25 ppb ..................... 0 0 20 2 0 0 2 1

SubRegion 10:

2–5 ppb ...................... 0 0 1 1 13 2 24 3

5–10 ppb .................... 0 0 0 0 4 1 4 1

10–15 ppb .................. 0 0 0 0 0 0 0 0

15–20 ppb .................. 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60387

TABLE II–9b. SUMMARY OF AIR QUALITY CONTRIBUTIONS TO DOWNWIND NONATTAINMENT, FOR SUBREGIONS 7–12—

Continued

Approach 1 Approach 2 Approach 3 Approach 4

1 Hr-violating co. 1 Hr-all grid cells 8 Hr-violating co. 8 Hr-all grid cells

Number impactsNumber

States

Number impactsNumber

States

Number impactsNumber

States

Number impactsNumber

States

20–25 ppb .................. 0 0 0 0 0 0 0 0

> 25 ppb ..................... 0 0 0 0 0 0 0 0

SubRegion 11:

2–5 ppb ...................... 11 2 19 3 21 6 37 7

5–10 ppb .................... 0 0 0 0 0 0 2 1

10–15 ppb .................. 0 0 0 0 0 0 0 0

15–20 ppb .................. 0 0 0 0 0 0 0 0

20–25 ppb .................. 0 0 0 0 0 0 0 0

> 25 ppb ..................... 0 0 0 0 0 0 0 0

SubRegion 12:

2–5 ppb ...................... 13 2 28 3 73 3 105 5

5–10 ppb .................... 11 1 19 1 0 0 0 0

10–15 ppb .................. 0 0 0 0 0 0 0 0

15–20 ppb .................. 0 0 0 0 0 0 0 0

20–25 ppb .................. 0 0 0 0 0 0 0 0

> 25 ppb ..................... 0 0 0 0 0 0 0 0

TABLE II–10.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 1: 1-HR ‘‘VIOLATING COUNTIES’’

Number of Impacts from SubRegion 1

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ N.A. 0 N.A. N.A. N.A. 0 0 0 0

5–10 ...................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

10–15 .................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

15–20 .................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

20–25 .................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

>25 ........................ N.A. 0 N.A. N.A. N.A. 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 22 0 0 7 20 21 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 2

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0
60388 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–10.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 1: 1-HR ‘‘VIOLATING COUNTIES’’—Continued

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 0 N.A. N.A. N.A. 0 0

5–10 ...................... 0 0 0 0 N.A. N.A. N.A. 0 0

10–15 .................... 0 0 0 0 N.A. N.A. N.A. 0 0

15–20 .................... 0 0 0 0 N.A. N.A. N.A. 0 0

20–25 .................... 0 0 0 0 N.A. N.A. N.A. 0 0

>25 ........................ 0 0 0 0 N.A. N.A. N.A. 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 0 0 0 0 0 0 5 0

5–10 ...................... 0 0 0 0 0 0 0 2 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 23 0 1 36 47 65 3 13 0 0 0

5–10 ...................... 23 0 0 4 6 3 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 3

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 0 0 0 0 0 0 19 1

5–10 ...................... 0 0 0 0 0 0 0 19 1

10–15 .................... 0 0 0 0 0 0 0 1 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 43 N.A. N.A. 8 N.A. 74 3 17 0 4 7

5–10 ...................... 47 N.A. N.A. 33 N.A. 78 3 6 0 0 0

10–15 .................... 19 N.A. N.A. 34 N.A. 13 0 0 0 0 0

15–20 .................... 4 N.A. N.A. 21 N.A. 2 0 0 0 0 0

20–25 .................... 0 N.A. N.A. 5 N.A. 0 0 0 0 0 0

>25 ........................ 0 N.A. N.A. 3 N.A. 0 0 0 0 0 0

Number of Impacts from SubRegion 4

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60389

TABLE II–10.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 1: 1-HR ‘‘VIOLATING COUNTIES’’—Continued

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 1 N.A. N.A. N.A. N.A. N.A. 0 1 0 8 0

5–10 ...................... 0 N.A. N.A. N.A. N.A. N.A. 0 9 0 1 2

10–15 .................... 0 N.A. N.A. N.A. N.A. N.A. 0 4 0 11 15

15–20 .................... 0 N.A. N.A. N.A. N.A. N.A. 0 4 0 3 0

20–25 .................... 0 N.A. N.A. N.A. N.A. N.A. 0 3 0 1 0

>25 ........................ 0 N.A. N.A. N.A. N.A. N.A. 6 30 0 1 0

Number of Impacts from SubRegion 5

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–1 ........................ 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–2 ...................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 N.A. 0 N.A. N.A. 11 0 N.A. 0

5–10 ...................... 0 N.A. 0 N.A. N.A. 4 0 N.A. 0

10–15 .................... 0 N.A. 0 N.A. N.A. 3 0 N.A. 0

15–20 .................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

20–25 .................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

>25 ........................ 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ N.A. 0 4 10 0 0 0 0 0

5–10 ...................... N.A. 0 0 2 0 0 0 0 0

10–15 .................... N.A. 0 2 3 0 0 0 0 0

15–20 .................... N.A. 0 1 2 0 0 0 0 0

20–25 .................... N.A. 0 0 0 0 0 0 0 0

>25 ........................ N.A. 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 8 0 2 10 6 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 6

Impacts (ppb): AR LA TX OK KS NE SD ND MN
60390 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–10.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 1: 1-HR ‘‘VIOLATING COUNTIES’’—Continued

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20—25 ................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 0 N.A. 0 N.A. N.A. N.A.

5–10 ...................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

10–15 .................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

15–20 .................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

20–25 .................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

>25 ........................ 0 0 0 0 N.A. 0 N.A. N.A. N.A.

TN MS AL GA FL SC NC VA DC

2–5 ........................ N.A. 0 0 0 0 0 0 N.A. 0

5–10 ...................... N.A. 0 0 0 0 0 0 N.A. 1

10–15 .................... N.A. 0 0 0 0 0 0 N.A. 0

15–20 .................... N.A. 0 0 0 0 0 0 N.A. 0

20–25 .................... N.A. 0 0 0 0 0 0 N.A. 0

>25 ........................ N.A. 0 0 0 0 0 0 N.A. 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 6 4 4 26 41 4 0 0 0 0 0

5–10 ...................... 52 6 4 32 16 9 2 0 0 0 0

10–15 .................... 17 0 2 2 4 0 0 0 0 0 0

15–20 .................... 2 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 4 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 7

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 0 0 0 0 0 N.A.

5–10 ...................... 0 0 0 0 0 0 0 0 N.A.

10–15 .................... 0 0 0 0 0 0 0 0 N.A.

15–20 .................... 0 0 0 0 0 0 0 0 N.A.

20–25 .................... 0 0 0 0 0 0 0 0 N.A.

>25 ........................ 0 0 0 0 0 0 0 0 N.A.

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 0 0 0 0 0 N.A. N.A. N.A.

5–10 ...................... 0 0 0 0 0 0 N.A. N.A. N.A.

10–15 .................... 0 0 0 0 0 0 N.A. N.A. N.A.

15–20 .................... 0 0 0 0 0 0 N.A. N.A. N.A.

20–25 .................... 0 0 0 0 0 0 N.A. N.A. N.A.

>25 ........................ 0 0 0 0 0 0 N.A. N.A. N.A.

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ N.A. N.A. 3 17 30 50 2 12 0 0 0

5–10 ...................... N.A. N.A. 2 28 52 31 0 0 0 0 0

10–15 .................... N.A. N.A. 13 14 15 8 0 0 0 0 0

15–20 .................... N.A. N.A. 11 4 4 2 0 0 0 0 0

20–25 .................... N.A. N.A. 2 6 0 0 0 0 0 0 0

>25 ........................ N.A. N.A. 7 12 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60391

TABLE II–10.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 1: 1-HR ‘‘VIOLATING COUNTIES’’—Continued

Number of Impacts from SubRegion 8

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 2 0 2 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 3 0 17 N.A. 0 N.A. N.A. 0 0

5–10 ...................... 0 0 0 N.A. 0 N.A. N.A. 0 0

10–15 .................... 0 0 0 N.A. 0 N.A. N.A. 0 0

15–20 .................... 0 0 1 N.A. 0 N.A. N.A. 0 0

20–25 .................... 0 0 0 N.A. 0 N.A. N.A. 0 0

>25 ........................ 0 0 0 N.A. 0 N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 0 0 4 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 9

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ N.A. 10 0 0 0 0 0 0 0

5–10 ...................... N.A. 0 0 0 0 0 0 0 0

10–15 .................... N.A. 0 0 0 0 0 0 0 0

15–20 .................... N.A. 0 0 0 0 0 0 0 0

20–25 .................... N.A. 0 0 0 0 0 0 0 0

>25 ........................ N.A. 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 1 0 0 0 0 0

5–10 ...................... 0 2 0 1 1 0 0 0 0

10–15 .................... 0 0 0 0 4 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

5–10 ...................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

10–15 .................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

15–20 .................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

20–25 .................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

>25 ........................ N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 0 0 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0
60392 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–10.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 1: 1-HR ‘‘VIOLATING COUNTIES’’—Continued

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 10

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ 0 N.A. 0 0 0 0 0 0 0

5–10 ...................... 0 N.A. 0 0 0 0 0 0 0

10–15 .................... 0 N.A. 0 0 0 0 0 0 0

15–20 .................... 0 N.A. 0 0 0 0 0 0 0

20–25 .................... 0 N.A. 0 0 0 0 0 0 0

>25 ........................ 0 N.A. 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 N.A. N.A. N.A. N.A. 0 0 0 0

5–10 ...................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

10–15 .................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

15–20 .................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

20–25 .................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

>25 ........................ 0 N.A. N.A. N.A. N.A. 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 0 0 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 11

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 ........................ N.A. N.A. N.A. N.A. 0 0 0 0 0

5–10 ...................... N.A. N.A. N.A. N.A. 0 0 0 0 0

10–15 .................... N.A. N.A. N.A. N.A. 0 0 0 0 0

15–20 .................... N.A. N.A. N.A. N.A. 0 0 0 0 0

20–25 .................... N.A. N.A. N.A. N.A. 0 0 0 0 0

>25 ........................ N.A. N.A. N.A. N.A. 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 ........................ 0 0 0 0 0 4 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 0 7 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 0 0 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60393

TABLE II–10.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 1: 1-HR ‘‘VIOLATING COUNTIES’’—Continued

15–20 .................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 12

Impacts (ppb): AR LA TX OK KS NE SD ND oi0MN

2–5 ........................ 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

5–10 ...................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

10–15 .................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

15–20 .................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

20–25 .................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

>25 ........................ 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

IA MO WI IL IN MI OH KY WV

2–5 ........................ N.A. N.A. N.A. 5 0 8 0 0 0

5–10 ...................... N.A. N.A. N.A. 0 0 11 0 0 0

10–15 .................... N.A. N.A. N.A. 0 0 0 0 0 0

15–20 .................... N.A. N.A. N.A. 0 0 0 0 0 0

20–25 .................... N.A. N.A. N.A. 0 0 0 0 0 0

>25 ........................ N.A. N.A. N.A. 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 ........................ 0 0 0 0 0 0 0 0 0

5–1 ........................ 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 ........................ 0 0 0 0 0 0 0 0 0 0 0

5–10 ...................... 0 0 0 0 0 0 0 0 0 0 0

10–15 .................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .................... 0 0 0 0 0 0 0 0 0 0 0

>25 ........................ 0 0 0 0 0 0 0 0 0 0 0

1 N.A. (Not Applicable) indicates that all or major portions of these States are part of the subregion and thus, are not considered as being

‘‘downwind’’.

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’

Number of Impacts from SubRegion 1

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 2 4

5–10 ........................................ 0 0 0 0 0 0 22 4 2

10–15 ...................................... 0 0 0 0 0 0 1 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... N.A. 0 N.A. N.A. N.A. 1 2 0 1

5–10 ........................................ N.A. 0 N.A. N.A. N.A. 6 8 0 0

10–15 ...................................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

15–20 ...................................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

20–25 ...................................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

>25 .......................................... N.A. 0 N.A. N.A. N.A. 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0
60394 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 24 0 0 16 35 23 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 0 0 0 0 0 2 4

5–10 ........................................ 0 0 0 0 0 0 22 4 2

10–15 ...................................... 0 0 0 0 0 0 1 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 2

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 N.A. N.A. N.A. 3 13

5–10 ........................................ 0 0 0 0 N.A. N.A. N.A. 0 14

10–15 ...................................... 0 0 0 0 N.A. N.A. N.A. 4 15

15–20 ...................................... 0 0 0 0 N.A. N.A. N.A. 1 5

20–25 ...................................... 0 0 0 0 N.A. N.A. N.A. 0 0

>25 .......................................... 0 0 0 0 N.A. N.A. N.A. 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 1 0 0 0 0 0 1 11 0

5–10 ........................................ 9 0 0 0 0 0 4 2 0

10–15 ...................................... 1 0 0 0 0 0 1 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 49 0 5 73 69 68 13 41 0

5–10 ........................................ 34 0 5 12 10 3 0 0 0

10–15 ...................................... 1 0 1 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 1 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 5 10 0 0 0 0 0 0 2

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 10

20–25 ...................................... 0 0 0 0 0 0 0 0 1

>25 .......................................... 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 3

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60395

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 2

10–15 ...................................... 0 0 0 0 0 0 0 0 8

15–20 ...................................... 0 0 0 0 0 0 0 0 5

20–25 ...................................... 0 0 0 0 0 0 0 0 1

>25 .......................................... 0 0 0 0 0 0 0 0 11

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 8 144 1

5–10 ........................................ 0 0 0 0 0 0 0 45 1

10–15 ...................................... 0 0 0 0 0 0 0 1 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 72 N.A. N.A. 28 N.A. 77 16 103 0

5–10 ........................................ 82 N.A. N.A. 70 N.A. 84 19 47 0

10–15 ...................................... 37 N.A. N.A. 115 N.A. 14 1 4 0

15–20 ...................................... 4 N.A. N.A. 30 N.A. 3 0 0 0

20–25 ...................................... 2 N.A. N.A. 6 N.A. 0 0 0 0

>25 .......................................... 7 N.A. N.A. 3 N.A. 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 12 23 0 0 0 0 0 0 1

5–10 ........................................ 7 19 0 0 0 0 0 0 3

10–15 ...................................... 0 0 0 0 0 0 0 0 1

15–20 ...................................... 0 0 0 0 0 0 0 0 2

20–25 ...................................... 0 0 0 0 0 0 0 0 1

>25 .......................................... 0 0 0 0 0 0 0 0 1

Number of Impacts from SubRegion 4

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 0 9 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 2 N.A. N.A. N.A. N.A. N.A. 0 14 0

5–10 ........................................ 0 N.A. N.A. N.A. N.A. N.A. 0 24 0

10–15 ...................................... 0 N.A. N.A. N.A. N.A. N.A. 0 33 0
60396 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

15–20 ...................................... 0 N.A. N.A. N.A. N.A. N.A. 0 32 0

20–25 ...................................... 0 N.A. N.A. N.A. N.A. N.A. 0 10 0

>25 .......................................... 0 N.A. N.A. N.A. N.A. N.A. 38 82 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 10 6 0 0 0 0 0 0 0

5–10 ........................................ 2 6 0 0 0 0 0 0 0

10–15 ...................................... 19 30 0 0 0 0 0 0 0

15–20 ...................................... 9 10 0 0 0 0 0 0 0

20–25 ...................................... 1 0 0 0 0 0 0 0 0

>25 .......................................... 1 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 5

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 2 0 0 0 0 0 0 0 0

5–10 ........................................ 9 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 N.A. 0 N.A. N.A. 18 3 N.A. 5

5–10 ........................................ 0 N.A. 0 N.A. N.A. 16 5 N.A. 0

10–15 ...................................... 0 N.A. 0 N.A. N.A. 6 0 N.A. 0

15–20 ...................................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

20–25 ...................................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

> 25 ........................................ 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... N.A. 0 12 19 0 0 0 0 0

5–10 ........................................ N.A. 0 0 12 0 0 0 0 0

10–15 ...................................... N.A. 0 5 5 0 0 0 0 0

15–20 ...................................... N.A. 0 3 2 0 0 0 0 0

20–25 ...................................... N.A. 0 5 0 0 0 0 0 0

> 25 ........................................ N.A. 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 16 0 2 45 9 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 70 0 0 7 4 1

5–10 ........................................ 0 0 ................ 151 0 0 16 2 1

10–15 ...................................... 0 0 ................ 60 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

> 25 ........................................ 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 6

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 N.A. 1 N.A. N.A. N.A.
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60397

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

5–10 ........................................ 0 0 0 0 N.A. 1 N.A. N.A. N.A.

10–15 ...................................... 0 0 0 0 N.A. 6 N.A. N.A. N.A.

15–20 ...................................... 0 0 0 0 N.A. 1 N.A. N.A. N.A.

20–25 ...................................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

> 25 ........................................ 0 0 0 0 N.A. 0 N.A. N.A. N.A.

TN MS AL GA FL SC NC VA DC

2–5 .......................................... N.A. 0 1 1 0 1 1 N.A. 0

5–10 ........................................ N.A. 0 0 0 0 0 1 N.A. 1

10–15 ...................................... N.A. 0 0 0 0 0 3 N.A. 0

15–20 ...................................... N.A. 0 0 0 0 0 1 N.A. 0

20–25 ...................................... N.A. 0 0 0 0 0 0 N.A. 0

> 25 ........................................ N.A. 0 0 0 0 0 7 N.A. 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 9 4 15 85 76 4 14 24 0

5–10 ........................................ 93 9 13 61 21 12 3 0 0

10–15 ...................................... 37 0 10 3 4 0 0 0 0

15–20 ...................................... 9 0 0 0 0 0 0 0 0

20–25 ...................................... 1 0 1 0 0 0 0 0 0

> 25 ........................................ 1 0 9 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 0 0 0 23 2 13

5–10 ........................................ 0 0 ................ 0 0 0 0 2 0

10–15 ...................................... 0 0 ................ 6 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

> 25 ........................................ 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 7

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 5 3 N.A.

5–10 ........................................ 0 0 0 0 0 0 0 0 N.A.

10–15 ...................................... 0 0 0 0 0 0 0 0 N.A.

15–20 ...................................... 0 0 0 0 0 0 0 0 N.A.

20–25 ...................................... 0 0 0 0 0 0 0 0 N.A.

> 25 ........................................ 0 0 0 0 0 0 0 0 N.A.

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 5 0 0 0 0 04 N.A. N.A. N.A.

5–10 ........................................ 1 0 0 0 0 01 N.A. N.A. N.A.

10–15 ...................................... 0 0 0 0 0 0 N.A. N.A. N.A.

15–20 ...................................... 0 0 0 0 0 0 N.A. N.A. N.A.

20–25 ...................................... 0 0 0 0 0 0 N.A. N.A. N.A.

> 25 ........................................ 0 0 0 0 0 0 N.A. N.A. N.A.

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... N.A. N.A. 16 39 77 54 8 32 0

5–10 ........................................ N.A. N.A. 27 56 75 34 4 13 0

10–15 ...................................... N.A. N.A. 20 32 19 9 5 5 0

15–20 ...................................... N.A. N.A. 17 18 10 2 0 0 0

20–25 ...................................... N.A. N.A. 6 14 0 0 0 0 0

> 25 ........................................ N.A. N.A. 13 52 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 3 3 0 0 0 0 0 0
60398 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

5–10 ........................................ 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 8

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 2 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 2 0 3 4 0 3 19 5

5–10 ........................................ 0 0 0 0 1 0 0 1 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 28 0 40 N.A. 0 N.A. N.A. 13 0

5–10 ........................................ 6 0 23 N.A. 0 N.A. N.A. 18 0

10–15 ...................................... 1 0 5 N.A. 0 N.A. N.A. 45 0

15–20 ...................................... 1 0 8 N.A. 0 N.A. N.A. 47 0

20–25 ...................................... 0 0 2 N.A. 0 N.A. N.A. 7 0

> 25 ........................................ 0 0 3 N.A. 0 N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 3 0 13 0 0 0 0 0 0

5–10 ........................................ 6 1 0 0 0 0 0 0 0

10–15 ...................................... 23 1 0 0 0 0 0 0 0

15–20 ...................................... 4 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 19 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 9

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... N.A. 27 0 0 0 0 0 0 0

5–10 ........................................ N.A. 0 0 0 0 0 0 0 0

10–15 ...................................... N.A. 0 0 0 0 0 0 0 0

15–20 ...................................... N.A. 0 0 0 0 0 0 0 0

20–25 ...................................... N.A. 0 0 0 0 0 0 0 0

> 25 ........................................ N.A. 1 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 2 5 0 5 22 5

5–10 ........................................ 0 2 0 2 4 1 3 24 0

10–15 ...................................... 0 0 0 0 5 0 0 6 0

15–20 ...................................... 0 0 0 0 0 0 0 6 0

20–25 ...................................... 0 0 0 0 0 0 0 4 0

> 25 ........................................ 0 0 0 0 0 0 0 19 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60399

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

TN MS AL GA FL SC NC VA DC

2–5 .......................................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 44 0

5–10 ........................................ N.A. N.A. N.A. N.A. 0 N.A. N.A. 32 0

10–15 ...................................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

15–20 ...................................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

20–25 ...................................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

> 25 ........................................ N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 28 2 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 5 0 0 12 2 1

5–10 ........................................ 0 0 ................ 17 0 0 11 0 0

10–15 ...................................... 0 0 ................ 2 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

> 25 ........................................ 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 10

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 N.A. 0 0 0 0 0 0 0

5–10 ........................................ 0 N.A. 0 0 0 0 0 0 0

10–15 ...................................... 0 N.A. 0 0 0 0 0 0 0

15–20 ...................................... 0 N.A. 0 0 0 0 0 0 0

20–25 ...................................... 0 N.A. 0 0 0 0 0 0 0

> 25 ........................................ 0 N.A. 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 N.A. N.A. N.A. N.A. 1 0 0 0

5–10 ........................................ 0 N.A. N.A. N.A. N.A. 0 0 0 0

10–15 ...................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

15–20 ...................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

20–25 ...................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

> 25 ........................................ 0 N.A. N.A. N.A. N.A. 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 0 0 0 0 0 0

5–10 ........................................ 0 0 ................ 0 0 0 0 0 0

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

> 25 ........................................ 0 0 ................ 0 0 0 0 0 0
60400 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

Number of Impacts from SubRegion 11

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

5–10 ........................................ N.A. N.A. N.A. N.A. 0 0 0 0 0

10–15 ...................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

15–20 ...................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

20–25 ...................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

> 25 ........................................ N.A. N.A. N.A. N.A. 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 1 0 11 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 7 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 38 0 0 0 0 0

5–10 ........................................ 0 0 ................ 0 0 0 0 0 0

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

> 25 ........................................ 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 12

Impact (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

5–10 ........................................ 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

10–15 ...................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

15–20 ...................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

20–25 ...................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

> 25 ........................................ 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

IA MO WI IL IN MI OH KY WV

2–5 .......................................... N.A. N.A. N.A. 8 2 18 0 0 0

5–10 ........................................ N.A. N.A. N.A. 0 0 19 0 0 0

10–15 ...................................... N.A. N.A. N.A. 0 0 0 0 0 0

15–20 ...................................... N.A. N.A. N.A. 0 0 0 0 0 0

20–25 ...................................... N.A. N.A. N.A. 0 0 0 0 0 0

> 25 ........................................ N.A. N.A. N.A. 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60401

TABLE II–11.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 2: 1-HR ‘‘ALL GRID CELLS’’—Continued

> 25 ........................................ 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

> 25 ........................................ 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 207 0 0 0 0 0

5–10 ........................................ 0 0 ................ 56 0 0 0 0 0

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0

1. N.A. (Not Applicable) indicates that all or major portions of these States are part of the subregion and thus, are not considered as being

‘‘downwind’’.

2. Codes for the Great Lakes are: LM-Lake Michigan; LS-Lake Superior; LH-Lake Huron; LE-Lake Erie; LC-Lake St. Clair; LO-Lake Ontario.

TABLE II–12.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 3: 8-HR ‘‘VIOLATING COUNTIES’’

Number of Impacts from SubRegion 1

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. N.A. 0 N.A. N.A. N.A. 9 25 3 5

5–10 ............................................ N.A. 0 N.A. N.A. N.A. 16 5 0 0

10–15 .......................................... N.A. 0 N.A. N.A. N.A. 1 0 0 0

15–20 .......................................... N.A. 0 N.A. N.A. N.A. 6 0 0 0

20–25 .......................................... N.A. 0 N.A. N.A. N.A. 5 0 0 0

>25 .............................................. N.A. 0 N.A. N.A. N.A. 1 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 1 0 14 1 22 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 2

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0
60402 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–12.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 3: 8-HR ‘‘VIOLATING COUNTIES’’—Continued

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 0 N.A. N.A. N.A. 13 7

5–10 ............................................ 0 0 0 0 N.A. N.A. N.A. 2 3

10–15 .......................................... 0 0 0 0 N.A. N.A. N.A. 0 0

15–20 .......................................... 0 0 0 0 N.A. N.A. N.A. 0 0

20–25 .......................................... 0 0 0 0 N.A. N.A. N.A. 0 0

>25 .............................................. 0 0 0 0 N.A. N.A. N.A. 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 1 0 0 0 0 0 10 9 1

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 36 9 42 45 25 19 1 5 0 8 8

5–10 ............................................ 2 0 26 0 4 0 0 0 0 0 0

10–15 .......................................... 0 0 6 0 4 0 0 0 0 0 0

15–20 .......................................... 0 0 2 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 5 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 1 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 3

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 0 0 0 7 0 0

5–10 ............................................ 0 0 0 0 0 0 0 6 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 0 0 0 0 0 0 00 26 0

5–10 ............................................ 0 0 0 0 0 0 0 7 1

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 28 N.A. N.A. 22 N.A. 31 8 44 0 12 28

5–10 ............................................ 32 N.A. N.A. 35 N.A. 38 1 25 0 1 0

10–15 .......................................... 7 N.A. N.A. 35 N.A. 3 0 0 0 0 0

15–20 .......................................... 0 N.A. N.A. 11 N.A. 0 0 0 0 0 0

20–25 .......................................... 0 N.A. N.A. 0 N.A. 0 0 0 0 0 0

>25 .............................................. 0 N.A. N.A. 0 N.A. 0 0 0 0 0 0

Number of Impacts from SubRegion 4

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60403

TABLE II–12.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 3: 8-HR ‘‘VIOLATING COUNTIES’’—Continued

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 0 N.A. N.A. N.A. N.A. N.A. 0 0 0 2 0

5–10 ............................................ 0 N.A. N.A. N.A. N.A. N.A. 0 11 0 6 20

10–15 .......................................... 0 N.A. N.A. N.A. N.A. N.A. 0 16 0 6 6

15–20 .......................................... 0 N.A. N.A. N.A. N.A. N.A. 1 17 0 0 4

20–25 .......................................... 0 N.A. N.A. N.A. N.A. N.A. 0 11 0 0 0

>25 .............................................. 0 N.A. N.A. N.A. N.A. N.A. 8 17 0 0 0

Number of Impacts from SubRegion 5

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 2 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 N.A. 0 N.A. N.A. 21 57 N.A. 9

5–10 ............................................ 0 N.A. 0 N.A. N.A. 64 68 N.A. 3

10–15 .......................................... 0 N.A. 0 N.A. N.A. 2 10 N.A. 0

15–20 .......................................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

20–25 .......................................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

>25 .............................................. 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. N.A. 0 2 3 0 0 1 6 0

5–10 ............................................ N.A. 0 4 1 0 0 0 0 0

10–15 .......................................... N.A. 0 0 0 0 0 0 0 0

15–20 .......................................... N.A. 0 0 0 0 0 0 0 0

20–25 .......................................... N.A. 0 0 0 0 0 0 0 0

>25 .............................................. N.A. 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 2 2 71 1 4 0 0 0 0 0 0

5–10 ............................................ 0 0 10 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 6

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 0 0 0 0 0 0 0 0
60404 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–12.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 3: 8-HR ‘‘VIOLATING COUNTIES’’—Continued

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 7 N.A. 23 N.A. N.A. N.A.

5–10 ............................................ 0 0 0 4 N.A. 20 N.A. N.A. N.A.

10–15 .......................................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

15–20 .......................................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

20–25 .......................................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

>25 .............................................. 0 0 0 0 N.A. 0 N.A. N.A. N.A.

TN MS AL GA FL SC NC VA DC

2–5 .............................................. N.A. 0 0 1 0 9 44 N.A. 0

5–10 ............................................ N.A. 0 0 0 0 4 29 N.A. 0

10–15 .......................................... N.A. 0 0 0 0 0 4 N.A. 0

15–20 .......................................... N.A. 0 0 0 0 0 0 N.A. 0

20–25 .......................................... N.A. 0 0 0 0 0 1 N.A. 0

>25 .............................................. N.A. 0 0 0 0 0 1 N.A. 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 42 19 72 44 15 44 1 22 0 0 0

5–10 ............................................ 14 14 53 18 3 2 0 0 0 0 0

10–15 .......................................... 0 2 40 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 10 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 7 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 7

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 0 0 0 6 0 N.A.

5–10 ............................................ 0 0 0 0 0 0 1 0 N.A.

10–15 .......................................... 0 0 0 0 0 0 0 0 N.A.

15–20 .......................................... 0 0 0 0 0 0 0 0 N.A.

20–25 .......................................... 0 0 0 0 0 0 0 0 N.A.

>25 .............................................. 0 0 0 0 0 0 0 0 N.A.

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 0 0 0 0 0 1 N.A. N.A. N.A.

5–10 ............................................ 0 0 0 0 0 0 N.A. N.A. N.A.

10–15 .......................................... 0 0 0 0 0 0 N.A. N.A. N.A.

15–20 .......................................... 0 0 0 0 0 0 N.A. N.A. N.A.

20–25 .......................................... 0 0 0 0 0 0 N.A. N.A. N.A.

>25 .............................................. 0 0 0 0 0 0 N.A. N.A. N.A.

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. N.A. N.A. 57 14 39 36 4 18 0 0 3

5–10 ............................................ N.A. N.A. 66 45 16 16 3 7 0 0 0

10–15 .......................................... N.A. N.A. 30 17 4 1 0 0 0 0 0

15–20 .......................................... N.A. N.A. 4 11 0 0 0 0 0 0 0

20–25 .......................................... N.A. N.A. 0 8 0 0 0 0 0 0 0

>25 .............................................. N.A. N.A. 0 8 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60405

TABLE II–12.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 3: 8-HR ‘‘VIOLATING COUNTIES’’—Continued

Number of Impacts from SubRegion 8

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 1 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 0 10 0 1 7 1

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 28 0 12 N.A. 0 N.A. N.A. 10 0

5–10 ............................................ 1 0 6 N.A. 0 N.A. N.A. 12 0

10–15 .......................................... 1 0 1 N.A. 0 N.A. N.A. 6 0

15–20 .......................................... 0 0 0 N.A. 0 N.A. N.A. 1 0

20–25 .......................................... 0 0 0 N.A. 0 N.A. N.A. 0 0

>25 .............................................. 0 0 0 N.A. 0 N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 0 0 13 6 10 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 9

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. N.A. 2 5 1 0 0 0 0 0

5–10 ............................................ N.A. 0 0 0 0 0 0 0 0

10–15 .......................................... N.A. 0 0 0 0 0 0 0 0

15–20 .......................................... N.A. 0 0 0 0 0 0 0 0

20–25 .......................................... N.A. 0 0 0 0 0 0 0 0

>25 .............................................. N.A. 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 10 18 52 31 23 5

5–10 ............................................ 0 2 0 9 11 0 2 40 0

10–15 .......................................... 0 0 0 0 3 0 0 24 0

15–20 .......................................... 0 0 0 0 0 0 0 2 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. N.A. N.A. N.A. N.A. 0 N.A. N.A. 14 0

5–10 ............................................ N.A. N.A. N.A. N.A. 0 N.A. N.A. 5 0

10–15 .......................................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

15–20 .......................................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

20–25 .......................................... N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

>25 .............................................. N.A. N.A. N.A. N.A. 0 N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 0 0 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0 0 0
60406 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–12.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 3: 8-HR ‘‘VIOLATING COUNTIES’’—Continued

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 10

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 N.A. 14 0 0 0 0 0 0

5–10 ............................................ 0 N.A. 4 0 0 0 0 0 0

10–15 .......................................... 0 N.A. 0 0 0 0 0 0 0

15–20 .......................................... 0 N.A. 0 0 0 0 0 0 0

20–25 .......................................... 0 N.A. 0 0 0 0 0 0 0

>25 .............................................. 0 N.A. 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 0 N.A. N.A. N.A. N.A. 1 0 0 0

5–10 ............................................ 0 N.A. N.A. N.A. N.A. 0 0 0 0

10–15 .......................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

15–20 .......................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

20–25 .......................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

>25 .............................................. 0 N.A. N.A. N.A. N.A. 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 0 0 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 11

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. N.A. N.A. N.A. N.A. 0 0 0 0 0

5–10 ............................................ N.A. N.A. N.A. N.A. 0 0 0 0 0

10–15 .......................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

15–20 .......................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

20–25 .......................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

>25 .............................................. N.A. N.A. N.A. N.A. 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .............................................. 0 1 0 9 2 2 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 2 0 5 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 0 0 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60407

TABLE II–12.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE,1 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 3: 8-HR ‘‘VIOLATING COUNTIES’’—Continued

15–20 .......................................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 12

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .............................................. 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

5–10 ............................................ 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

10–15 .......................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

15–20 .......................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

20–25 .......................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

>25 .............................................. 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

IA MO WI IL IN MI OH KY WV

2–5 .............................................. N.A. N.A. N.A. 14 7 52 0 0 0

5–10 ............................................ N.A. N.A. N.A. 0 0 0 0 0 0

10–15 .......................................... N.A. N.A. N.A. 0 0 0 0 0 0

15–20 .......................................... N.A. N.A. N.A. 0 0 0 0 0 0

20–25 .......................................... N.A. N.A. N.A. 0 0 0 0 0 0

>25 .............................................. N.A. N.A. N.A. 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .............................................. 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT NH ME

2–5 .............................................. 0 0 0 0 0 0 0 0 0 0 0

5–10 ............................................ 0 0 0 0 0 0 0 0 0 0 0

10–15 .......................................... 0 0 0 0 0 0 0 0 0 0 0

15–20 .......................................... 0 0 0 0 0 0 0 0 0 0 0

20–25 .......................................... 0 0 0 0 0 0 0 0 0 0 0

>25 .............................................. 0 0 0 0 0 0 0 0 0 0 0

1 N.A. (Not Applicable) indicates that all or major portions of these States are part of the subregion and thus, are not considered as being

‘‘downwind’’.

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’

Number of Impacts from SubRegion 1

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... N.A. 0 N.A. N.A. N.A. 10 64 5 39

5–10 ........................................ N.A. 0 N.A. N.A. N.A. 20 8 0 0

10–15 ...................................... N.A. 0 N.A. N.A. N.A. 5 0 0 0

15–20 ...................................... N.A. 0 N.A. N.A. N.A. 11 0 0 0

20–25 ...................................... N.A. 0 N.A. N.A. N.A. 10 0 0 0

>25 .......................................... N.A. 0 N.A. N.A. N.A. 1 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 0 1 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0
60408 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 1 0 20 3 36 0 1 0 0

5–10 ........................................ 0 0 0 01 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–2 ........................................ 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 0 0 24 65 0 64

5–10 ........................................ 0 0 ................ 0 0 13 25 3 4

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 1 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 2

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 N.A. N.A. N.A. 18 69

5–10 ........................................ 0 0 0 0 N.A. N.A. N.A. 2 39

10–15 ...................................... 0 0 0 0 N.A. N.A. N.A. 0 0

15–20 ...................................... 0 0 0 0 N.A. N.A. N.A. 0 0

20–25 ...................................... 0 0 0 0 N.A. N.A. N.A. 0 0

>25 .......................................... 0 0 0 0 N.A. N.A. N.A. 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 2 0 0 0 0 0 11 20 1

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 56 11 89 70 34 20 1 9 0

5–10 ........................................ 2 0 46 2 10 0 0 0 0

10–15 ...................................... 0 0 7 0 8 0 0 0 0

15–20 ...................................... 0 0 3 0 3 0 0 0 0

20–25 ...................................... 0 0 5 0 1 0 0 0 0

>25 .......................................... 0 0 1 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 9 12 ................ 1 0 0 0 0 20

5–10 ........................................ 0 0 ................ 0 0 0 0 0 32

10–15 ...................................... 0 0 ................ 0 0 0 1 0 17

15–20 ...................................... 0 0 ................ 0 0 0 10 0 1

20–25 ...................................... 0 0 ................ 0 0 0 13 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 3

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60409

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 10 0 25

5–10 ........................................ 0 0 0 0 0 0 6 0 19

10–15 ...................................... 0 0 0 0 0 0 0 0 7

15–20 ...................................... 0 0 0 0 0 0 0 0 1

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 0 76 0

5–10 ........................................ 0 0 0 0 0 0 0 32 1

10–15 ...................................... 0 0 0 0 0 0 0 4 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 82 N.A. N.A. 83 N.A. 34 16 96 0

5–10 ........................................ 44 N.A. N.A. 51 N.A. 40 1 30 0

10–15 ...................................... 13 N.A. N.A. 41 N.A. 4 0 0 0

15–20 ...................................... 1 N.A. N.A. 12 N.A. 0 0 0 0

20–25 ...................................... 0 N.A. N.A. 0 N.A. 0 0 0 0

>25 .......................................... 0 N.A. N.A. 0 N.A. 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 21 84 ................ 0 0 0 0 0 4

5–10 ........................................ 4 8 ................ 0 0 0 0 0 6

10–15 ...................................... 0 0 ................ 0 0 0 0 0 15

15–20 ...................................... 0 0 ................ 0 0 0 0 0 35

20–25 ...................................... 0 0 ................ 0 0 0 0 0 8

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 4

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

25 ............................................ 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–2 ........................................ 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 0 N.A. N.A. N.A. N.A. N.A. 0 0 0
60410 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

5–10 ........................................ 0 N.A. N.A. N.A. N.A. N.A. 0 42 0

10–15 ...................................... 0 N.A. N.A. N.A. N.A. N.A. 0 38 0

15–20 ...................................... 0 N.A. N.A. N.A. N.A. N.A. 1 22 0

20–25 ...................................... 0 N.A. N.A. N.A. N.A. N.A. 4 15 0

>25 .......................................... 0 N.A. N.A. N.A. N.A. N.A. 12 17 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 3 0 ................ 0 0 0 0 0 0

5–10 ........................................ 10 32 ................ 0 0 0 0 0 0

10–15 ...................................... 11 42 ................ 0 0 0 0 0 0

15–20 ...................................... 2 21 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 5

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 3 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 N.A. 0 N.A. N.A. 26 122 N.A. 101

5–10 ........................................ 0 N.A. 0 N.A. N.A. 89 132 N.A. 22

10–15 ...................................... 0 N.A. 0 N.A. N.A. 7 16 N.A. 0

15–20 ...................................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

20–25 ...................................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

>25 .......................................... 0 N.A. 0 N.A. N.A. 0 0 N.A. 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... N.A. 1 8 9 0 0 2 19 0

5–10 ........................................ N.A. 0 8 2 0 0 0 0 0

10–15 ...................................... N.A. 0 0 0 0 0 0 0 0

15–20 ...................................... N.A. 0 0 0 0 0 0 0 0

20–25 ...................................... N.A. 0 0 0 0 0 0 0 0

>25 .......................................... N.A. 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 20 3 163 4 12 0 0 0 0

5–10 ........................................ 5 0 24 0 1 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 75 0 32 63 0 54

5–10 ........................................ 0 0 ................ 86 0 9 31 3 0

10–15 ...................................... 0 0 ................ 17 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 6

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60411

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 7 N.A. 31 N.A. N.A. N.A.

5–10 ........................................ 0 0 0 4 N.A. 31 N.A. N.A. N.A.

10–15 ...................................... 0 0 0 0 N.A. 1 N.A. N.A. N.A.

15–20 ...................................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

20–25 ...................................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

>25 .......................................... 0 0 0 0 N.A. 0 N.A. N.A. N.A.

TN MS AL GA FL SC NC VA DC

2–5 .......................................... N.A. 0 0 1 0 20 70 N.A. 0

5–10 ........................................ N.A. 0 0 0 0 9 47 N.A. 0

10–15 ...................................... N.A. 0 0 0 0 0 8 N.A. 0

15–20 ...................................... N.A. 0 0 0 0 0 0 N.A. 0

20–25 ...................................... N.A. 0 0 0 0 0 1 N.A. 0

>25 .......................................... N.A. 0 0 0 0 0 1 N.A. 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 95 39 92 77 21 47 1 22 0

5–10 ........................................ 46 15 104 20 3 2 0 0 0

10–15 ...................................... 15 2 94 0 0 0 0 0 0

15–20 ...................................... 6 0 23 0 0 0 0 0 0

20–25 ...................................... 0 0 13 0 0 0 0 0 0

>25 .......................................... 0 0 1 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 52 0 27 51 0 40

5–10 ........................................ 0 0 ................ 84 0 12 12 0 1

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 7

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–1 .......................................... 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 9 0 N.A.

5–10 ........................................ 0 0 0 0 0 0 1 0 N.A.

10–15 ...................................... 0 0 0 0 0 0 0 0 N.A.

15–20 ...................................... 0 0 0 0 0 0 0 0 N.A.

20–25 ...................................... 0 0 0 0 0 0 0 0 N.A.

>25 .......................................... 0 0 0 0 0 0 0 0 N.A.

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 2 N.A. N.A. N.A.

5–10 ........................................ 0 0 0 0 0 0 N.A. N.A. N.A.

10–15 ...................................... 0 0 0 0 0 0 N.A. N.A. N.A.

15–20 ...................................... 0 0 0 0 0 0 N.A. N.A. N.A.

20–25 ...................................... 0 0 0 0 0 0 N.A. N.A. N.A.

>25 .......................................... 0 0 0 0 0 0 N.A. N.A. N.A.

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... N.A. N.A. 117 18 44 37 7 39 0

5–10 ........................................ N.A. N.A. 120 59 20 17 4 12 0

10–15 ...................................... N.A. N.A. 35 32 18 2 0 0 0

15–20 ...................................... N.A. N.A. 4 31 0 0 0 0 0

20–25 ...................................... N.A. N.A. 0 12 0 0 0 0 0

>25 .......................................... N.A. N.A. 0 35 0 0 0 0 0
60412 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 5 37 ................ 0 0 0 0 0 0

5–10 ........................................ 0 0 ................ 0 0 0 0 0 0

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 8

Impacts (ppb) AR LA TX OK KS NE SD ND MN

2–5 .......................................... 1 0 0 0 0 0 0 0 0

5–1 .......................................... 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 15 0 1 24 1

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 53 0 46 N.A. 0 N.A. N.A. 27 0

5–10 ........................................ 9 0 27 N.A. 0 N.A. N.A. 79 0

10–15 ...................................... 1 0 2 N.A. 0 N.A. N.A. 38 0

15–20 ...................................... 0 0 0 N.A. 0 N.A. N.A. 21 0

20–25 ...................................... 0 0 0 N.A. 0 N.A. N.A. 6 0

>25 .......................................... 0 0 0 N.A. 0 N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 31 8 32 26 0 0 0 0 0

5–10 ........................................ 18 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 0 0 0 0 0 0

5–10 ........................................ 0 0 ................ 0 0 0 0 0 0

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 9

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... N.A. 0 3 5 0 0 0 0 0

5–10 ........................................ N.A. 0 0 0 0 0 0 0 0

10–15 ...................................... N.A. 0 0 0 0 0 0 0 0

15–20 ...................................... N.A. 0 0 0 0 0 0 0 0

20–25 ...................................... N.A. 0 0 0 0 0 0 0 0

>25 .......................................... N.A. 0 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 10 22 70 67 73 26

5–10 ........................................ 0 2 0 21 38 0 2 116 0

10–15 ...................................... 0 0 0 1 9 0 0 57 0

15–20 ...................................... 0 0 0 0 0 0 0 8 0

20–25 ...................................... 0 0 0 0 0 0 0 2 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60413

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

>25 .......................................... 0 0 0 0 0 0 0 2 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... N.A. N.A. N.A. N.A. N.A. N.A. N.A. 47 0

5–10 ........................................ N.A. N.A. N.A. N.A. N.A. N.A. N.A. 18 0

10–15 ...................................... N.A. N.A. N.A. N.A. N.A. N.A. N.A. 0 0

15–20 ...................................... N.A. N.A. N.A. N.A. N.A. N.A. N.A. 0 0

20–25 ...................................... N.A. N.A. N.A. N.A. N.A. N.A. N.A. 0 0

>25 .......................................... N.A. N.A. N.A. N.A. N.A. N.A. N.A. 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 6 0 9 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 1 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 0 59 0 0 6 3 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 1 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 10

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 N.A. 3 14 0 0 0 0 0

5–10 ........................................ 0 N.A. 14 4 0 0 0 0 0

10–15 ...................................... 0 N.A. 4 0 0 0 0 0 0

15–20 ...................................... 0 N.A. 0 0 0 0 0 0 0

20–25 ...................................... 0 N.A. 0 0 0 0 0 0 0

>25 .......................................... 0 N.A. 0 0 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 1 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 4 N.A. N.A. N.A. N.A. 6 0 0 0

5–10 ........................................ 0 N.A. N.A. N.A. N.A. 0 0 0 0

10–15 ...................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

15–20 ...................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

20–25 ...................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

>25 .......................................... 0 N.A. N.A. N.A. N.A. 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 1 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 1 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0
60414 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

>25 .......................................... 0 0 0 0 0 0 0 0 0

Number of Impacts from SubRegion 11

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

5–10 ........................................ N.A. N.A. N.A. N.A. 0 0 0 0 0

10–15 ...................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

15–20 ...................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

20–25 ...................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

>25 .......................................... N.A. N.A. N.A. N.A. 0 0 0 0 0

IA MO WI IL IN MI OH KY WV

2–5 .......................................... 0 1 0 15 2 2 0 6 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 6 0 5 0 0 0 0 0 0

5–10 ........................................ 0 2 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

≤ 25 ......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 0 0 0 0 0 0

5–10 ........................................ 0 0 ................ 0 0 0 0 0 0

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

Number of Impacts from SubRegion 12

Impacts (ppb): AR LA TX OK KS NE SD ND MN

2–5 .......................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

5–10 ........................................ 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

10–15 ...................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

15–20 ...................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

20–25 ...................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

>25 .......................................... 0 0 0 N.A. N.A. N.A. N.A. N.A. N.A.

IA MO WI IL IN MI OH KY WV

2–5 .......................................... N.A. N.A. N.A. 17 7 74 0 6 0

5–10 ........................................ N.A. N.A. N.A. 0 0 0 0 0 0

10–15 ...................................... N.A. N.A. N.A. 0 0 0 0 0 0

15–20 ...................................... N.A. N.A. N.A. 0 0 0 0 0 0

20–25 ...................................... N.A. N.A. N.A. 0 0 0 0 0 0

>25 .......................................... N.A. N.A. N.A. 0 0 0 0 0 0

TN MS AL GA FL SC NC VA DC

2–5 .......................................... 0 0 0 0 0 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60415

TABLE II–13.—NUMBER OF IMPACTS IN EACH ‘‘DOWNWIND’’ STATE 1,2 BY IMPACT CONCENTRATION RANGE FOR EACH

SUBREGION—APPROACH 4: 8–HR ‘‘ALL GRID CELLS’’—Continued

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

MD DE PA NJ NY CT RI MA VT

2–5 .......................................... 0 0 0 0 1 0 0 0 0

5–10 ........................................ 0 0 0 0 0 0 0 0 0

10–15 ...................................... 0 0 0 0 0 0 0 0 0

15–20 ...................................... 0 0 0 0 0 0 0 0 0

20–25 ...................................... 0 0 0 0 0 0 0 0 0

>25 .......................................... 0 0 0 0 0 0 0 0 0

NH ME blank LM LS LH LE LC LO

2–5 .......................................... 0 0 ................ 125 0 0 6 0 0

5–10 ........................................ 0 0 ................ 0 0 0 0 0 0

10–15 ...................................... 0 0 ................ 0 0 0 0 0 0

15–20 ...................................... 0 0 ................ 0 0 0 0 0 0

20–25 ...................................... 0 0 ................ 0 0 0 0 0 0

>25 .......................................... 0 0 ................ 0 0 0 0 0 0

1 N.A. (Not Applicable) indicates that all or major portions of these States are part of the subregion and thus, are not considered as being

‘‘downwind’’. 2 Codes for the Great Lakes are: LM—Lake Michigan; LS—Lake Superior; LH—Lake Huron; LE—Lake Erie; LC—Lake St Clair; LO—Lake Ontario.

TABLE II–14a.—PERCENT OF 2007 STATE TOTAL NOX EMISSIONS BY SUBREGION

Percent of State Emissions in Each Subregion

SUBR–

1

SUBR–

2

SUBR–

3

SUBR–

4

SUBR–

5

SUBR–

6

SUBR–

7

SUBR–

8

SUBR–

9

SUBR–

10

SUBR–

11

SUBR–

12 OTHER

TX ....................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00 ............ ............

OH ...................... ............ 33.30 ............ ............ ............ 66.70 ............ ............ ............ ............ ............ ............ ............

PA ...................... ............ 0.30 79.05 20.61 ............ 0.04 ............ ............ ............ ............ ............ ............ ............

IL ........................ 49.45 ............ ............ ............ 50.53 ............ ............ ............ ............ ............ ............ 0.02 ............

FL ....................... ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00 ............ ............ ............

LA ....................... ............ ............ ............ ............ ............ ............ ............ ............ ............ 40.99 59.01 ............ ............

MI ....................... 8.68 83.32 ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 8.00

IN ........................ 28.70 7.03 ............ ............ 41.68 22.59 ............ ............ ............ ............ ............ ............ ............

TN ...................... ............ ............ ............ ............ 16.71 10.09 ............ 0.63 72.58 ............ ............ ............ ............

GA ...................... ............ ............ ............ ............ ............ ............ ............ 6.47 74.19 19.34 ............ ............ ............

NY ...................... ............ ............ 31.09 49.56 ............ ............ ............ ............ ............ ............ ............ ............ 19.35

KY ...................... ............ ............ ............ ............ 39.00 61.00 ............ ............ ............ ............ ............ ............ ............

AL ....................... ............ ............ ............ ............ ............ ............ ............ ............ 73.40 26.60 ............ ............ ............

NC ...................... ............ ............ ............ ............ ............ 0.74 13.14 78.04 8.08 ............ ............ ............ ............

VA ...................... ............ ............ ............ ............ ............ 7.72 92.20 ............ ............ ............ ............ ............ 0.08

WV ..................... ............ ............ 3.70 ............ ............ 74.64 21.66 ............ ............ ............ ............ ............ ............

NJ ....................... ............ ............ 0.81 98.98 ............ ............ 0.21 ............ ............ ............ ............ ............ ............

MO ..................... ............ ............ ............ ............ 43.60 ............ ............ ............ 0.61 ............ ............ 55.78 ............

OK ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 86.99 13.01 ............

KS ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00 ............

SC ...................... ............ ............ ............ ............ ............ ............ ............ 93.12 6.44 0.43 ............ ............ ............

MS ...................... ............ ............ ............ ............ ............ ............ ............ ............ 49.69 45.56 4.75 ............ ............

WI ....................... 87.53 ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 6.02 6.45

MD ...................... ............ ............ 3.11 0.48 ............ ............ 96.12 ............ ............ ............ ............ ............ 0.29

MN ...................... 0.30 ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 99.70 ............

IA ........................ 22.97 ............ ............ ............ 2.73 ............ ............ ............ ............ ............ ............ 74.30 ............

MA ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00

AR ...................... ............ ............ ............ ............ 0.40 ............ ............ ............ 10.54 ............ 85.36 3.71 ............

NE ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00 ............

CT ...................... ............ ............ ............ 96.60 ............ ............ ............ ............ ............ ............ ............ ............ 3.40

ME ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00

NH ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00

DE ...................... ............ ............ 33.57 23.69 ............ ............ 42.74 ............ ............ ............ ............ ............ ............

SD ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00 ............

RI ........................ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00

VT ....................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00

ND ...................... ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ ............ 100.00 ............

DC ...................... ............ ............ ............ ............ ............ ............ 100.00 ............ ............ ............ ............ ............ ............
60416 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

1The emission reductions avoided are assessed

assuming a slightly different regional NOX strategy

than the strategy analyzed in this notice. However,

the results here are nonetheless illustrative of the

potential savings associated with a similar regional

NOX strategy.

2To inflate cost estimates, use CPI inflator: 1990

to 1995=1.17; 1990 to 1996=1.20

TABLE II–14b.—PERCENT 2007 BASELINE NOX Emissions by Subregion,

by State

Subregion/State

Percent of

subregion

total NOX

1:

Illinois .................................... 39.50

Indiana ................................... 19.49

Iowa ....................................... 5.63

Michigan ................................ 6.39

Minnesota .............................. 0.07

Wisconsin .............................. 28.90

Percent of Domain Total ... 6.21

2:

Indiana ................................... 4.69

Michigan ................................ 60.19

Ohio ....................................... 27.60

Pennsylvania ......................... 0.23

Canada .................................. 7.29

Percent of Domain Total ... 6.34

3:

Delaware ............................... 2.27

Maryland ................................ 0.92

New Jersey ........................... 0.34

New York ............................... 18.62

Pennsylvania ......................... 66.51

West Virginia ......................... 1.69

Canada .................................. 9.63

Percent of Domain Total ... 5.91

4:

Connecticut ........................... 12.15

Delaware ............................... 1.55

Maryland ................................ 0.14

New Jersey ........................... 40.56

New York ............................... 28.79

Pennsylvania ......................... 16.81

Percent of Domain Total ... 6.09

5:

Arkansas ............................... 0.08

Illinois .................................... 34.35

Indiana ................................... 24.09

Iowa ....................................... 0.57

Kentucky ................................ 17.42

Missouri ................................. 14.04

Tennessee ............................. 9.45

Percent of Domain Total ... 7.30

6:

Illinois .................................... 0.00

Indiana ................................... 10.45

Kentucky ................................ 21.80

North Carolina ....................... 0.25

Ohio ....................................... 38.39

Pennsylvania ......................... 0.02

Tennessee ............................. 4.57

TABLE II–14b.—PERCENT 2007 BASELINE NOX Emissions by Subregion,

by State—Continued

Subregion/State

Percent of

subregion

total NOX

Virginia .................................. 2.39

West Virginia ......................... 22.12

Percent of Domain Total ... 9.12

7:

Delaware ............................... 3.06

District of Col ......................... 2.01

Maryland ................................ 30.20

New Jersey ........................... 0.09

North Carolina ....................... 7.34

Pennsylvania ......................... 0.00

Virginia .................................. 46.78

West Virginia ......................... 10.50

Percent of Domain Total ... 5.57

8:

Georgia .................................. 5.05

North Carolina ....................... 51.88

Pennsylvania ......................... 0.00

South Carolina ...................... 42.52

Tennessee ............................. 0.55

Percent of Domain Total ... 4.69

9:

Alabama ................................ 24.11

Arkansas ............................... 1.55

Georgia .................................. 28.23

Louisiana ............................... 0.00

Mississippi ............................. 10.71

Missouri ................................. 0.15

North Carolina ....................... 2.62

South Carolina ...................... 1.44

Tennessee ............................. 31.20

Percent of Domain Total ... 9.61

10:

Alabama ................................ 8.90

Florida ................................... 50.02

Georgia .................................. 7.50

Louisiana ............................... 19.91

Mississippi ............................. 10.00

South Carolina ...................... 0.10

Off Shore ............................... 3.57

Percent of Domain Total ... 9.43

11:

Arkansas ............................... 7.96

Louisiana ............................... 17.88

Mississippi ............................. 0.65

Oklahoma .............................. 13.09

Texas ..................................... 57.47

Off Shore ............................... 2.95

Percent of Domain Total ... 15.11

12:

Arkansas ............................... 0.67

TABLE II–14b.—PERCENT 2007 BASELINE NOX Emissions by Subregion,

by State—Continued

Subregion/State

Percent of

subregion

total NOX

Illinois .................................... 0.02

Iowa ....................................... 14.52

Kansas .................................. 27.99

Minnesota .............................. 19.95

Missouri ................................. 16.82

Nebraska ............................... 9.96

North Dakota ......................... 1.47

Oklahoma .............................. 3.79

South Dakota ........................ 3.22

Wisconsin .............................. 1.58

Percent of Domain Total ... 17.80

Table II–15.—Estimate of Local Control Cost

Avoided by OTAG Strategy 1, 2

23–Jurisdictions VOC Emission Reductions

Avoided: 513,000 (tpy)

Low-end Local VOC Removal Cost per ton:

$2,400 (Average cost of local VOC

measures selected in RIA)

High-end Local VOC Removal Cost per ton:

$10,000 (Integrated Implementation Plan

limit)

23–Jurisdictions NOX Emission Reductions

Avoided: 767,000 (tpy)

Low-end Local NOX Removal Cost per ton:

$2,200 (Average cost of local VOC

measures selected in RIA)

High-end Local NOX Removal Cost per ton:

$10,000 (Integrated Implementation Plan

limit)

23—Jurisdiction Local VOC Removal Cost

Avoided (million 1990$): Low-end $1,231;

High-end $5,131

23—Jurisdiction Local NOX Removal Cost

Avoided (million 1990$): Low-end $1,687;

High-end $7,671

23—Jurisdiction Total Removal Cost Avoided

(million 1990$): Low-end $2,918; High-end

$12,802

BILLING CODE 6560–50–M
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60417

Appendix D—Figures for Section II.

Weight of Evidence Determination of Significant Contribution

Figure II–1. OTAG Modeling Domain.
60418 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

Figure II–2.—Location of Subregions.
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60419

Figure II–3.—OTAG Round 3 Geographic Zones (shaded areas are 3 ‘‘major’’ nonattainment areas).
60420 Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules

Figure II–4.—Transport Wind Vectors During Regionally High Ozone Days.

BILLING CODE 6560–50–C
Federal Register / Vol. 62, No. 216 / Friday, November 7, 1997 / Proposed Rules 60421

Appendix E—Control Strategies Contained

in Model Run 5 of the Ozone Transport

Assessment Group

Utility

Mandated CAA controls

• Acid Rain Controls (Phase 1 & 2 for all

boiler types)

• RACT & NSR in nonattainment areas

(NAAs) without waivers

Additional controls

• OTC NOX MOU (Phase II)

• 85 percent reduction from 1990 rate or

rate-base of 0.15 lb/mmbtu for all units,

whichever is less stringent

Non-Utility Point Sources

Mandated CAA controls

• RACT at major sources in NAAs without

waivers

• 250 Ton PSD and NSPS (not modeled)

• NSR in NAAs without waivers (not

modeled)

• CTG & Non-CTG RACT at major sources in

NAAs & throughout OTC

• New Source LAER & Offsets for NAAs (not

modeled)

• ‘‘9 percent by 99’’ ROP Measures (VOC or

NOX) for serious and above areas

Additional controls

• NOX Controls based on cost per ton of

reduction (< $1,000 per ton)—primarily

LNB technology

Nonroad Mobile

Mandated CAA controls

• Federal Phase II Small Engine Standards

• Federal Marine Engine Standards

• Federal HDV (>=50 hp) Standards—Phase

1

• Federal RFG II (statutory and opt-in areas)

• 9.0 RVP maximum elsewhere in OTAG

• ‘‘9 percent by 99’’ ROP Measures(VOC or

NOX) for serious and above areas

Additional controls

• Federal Locomotive Standards (including

rebuilds)

• HD Engine 4gm Standard

Highway Mobile

Mandated CAA controls

• Tier 1 light-duty and heavy-duty Standards

• Federal reformulated gas (RFG II) (statutory

and opt-in areas)

• High Enhanced I/M (serious and above

areas)

• Low Enhanced I/M for rest of OTR

• Basic I/M (mandated areas)

• Clean Fuel Fleets (mandated areas)

• 9.0 RVP maximum elsewhere in OTAG

• On board vapor recovery

Additional controls

• National LEV

• Heavy Duty Vehicle 2 gm Standard

• Federal Test Procedure (FTP) revisions

• ‘‘9 percent by 99’’ ROP Measures (if

substitute for VOC) in serious and above

areas

Other Area Source Controls

Mandated CAA controls

• Two Phases of Consumer & Commercial

Products & One Phase of Architectural

Coatings

• Stage 1 & 2 Petroleum Distribution

Controls—NAAs

• Autobody, Degreasing & Dry Cleaning

Controls in NAAs

• ‘‘9 percent by 99’’ ROP Measures (VOC or

NOX) (serious and above areas)

[FR Doc. 97–28932 Filed 11–6–97; 8:45 am]

BILLING CODE 6560–50–P–M