Approval and Promulgation of Air Quality Implementation Plans for Air Quality Planning Purposes; Ohio

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

[OH-16-1-5320; FRL-4830-4]

Approval and Promulgation of Air Quality Implementation Plans for

Air Quality Planning Purposes; Ohio

AGENCY: Environmental Protection Agency.

ACTION: Proposed rule.

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SUMMARY: The Environmental Protection Agency (EPA) proposes to

conditionally approve revisions to the emission limitations, compliance

methodologies, and compliance time schedules in Ohio's State

Implementation Plan for sulfur dioxide (SO2) as it applies to

sources in Hamilton County. These revisions are being proposed in

response to modeling analyses which have predicted violations of the

SO2 National Ambient Air Quality Standards (NAAQS) due to

emissions from sources in Hamilton County.

DATES: Comments on this requested revision and on the proposed EPA

action must be received by February 28, 1994.

ADDRESSES: Written comments should be addressed to: William MacDowell,

Chief, Regulatory Development Section, Air EnforcementBranch (AE-17J),

United States Environmental Protection Agency, 77 West Jackson

Boulevard, Chicago, Illinois 60604.

FOR FURTHER INFORMATION CONTACT: Randy Robinson, Air Enforcement Branch

(AE-17J), United States Environmental Protection Agency, Region 5,

Chicago, Illinois 60604, (312) 353-6713.

SUPPLEMENTARY INFORMATION:

EPA's analysis is discussed in the following manner: I. Background;

II. Attainment Demonstration; III. Compliance; and IV. Proposed Action.

I. Background

The Environmental Protection Agency (EPA) approved portions of the

Ohio SO2 State Implementation Plan (SIP) for Hamilton County on

January 27, 1981 (46 FR 8481), and April 20, 1982 (47 FR 16784), and

the remaining portion on May 13, 1982 (47 FR 20586). The portion of

Hamilton County which was originally designated a nonattainment area

for SO2 was redesignated to attainment on March 19, 1982 (47 FR

11870). Hamilton County was divided into two separate attainment areas

on May 13, 1982 (47 FR 20586). However, since the time of those

rulemakings, three modeling analyses have been submitted to EPA which

predicted violations of the SO2 National Ambient Air Quality

Standards (NAAQS) due to SO2 emissions from existing sources that

are located in Hamilton County, Ohio.

Based on the predicted violations, EPA notified the Governor of

Ohio on December 22, 1988, under section 110(a)(2)(H) of the Clean Air

Act, 42 U.S.C. 7410(a)(2)(H), that the SIP for SO2 is

substantially inadequate to attain and maintain the SO2 NAAQS in

Hamilton County. The notification provided the State with 60 days to

submit a commitment and schedule for the development of an approvable

SIP and up to 18 months from the date of notification to submit a fully

State adopted SO2 plan for Hamilton County, which assures the

attainment and maintenance of the SO2 NAAQS both in Hamilton

County and the surrounding area.

On June 28, 1991, Valdas V. Adamkus, Regional Administrator, EPA,

sent a letter to Donald R. Schregardus, Director, OEPA formalizing an

agreement between EPA and OEPA regarding action toward SO2

attainment status for Hamilton County, Ohio. On September 9, 1991, OEPA

sent EPA a proposed revision to the Hamilton County SO2 SIP. The

signed State adopted rules were received by EPA on October 18, 1991.

The rules package submitted for approval consisted of revisions to Ohio

Administrative Code (OAC) 3745-18-03 Attainment Dates and Compliance

Time Schedules, (OAC) 3745-18-04 Measurement Methods and Procedures,

and OAC 3745-18-37 Hamilton County Emission Limits, as well as a

modeling analysis intended to demonstrate that the limits in these

regulations are sufficient to assure attainment of the NAAQS for

SO2 in Hamilton County. A completeness review was performed and,

on November 8, 1991, EPA determined that the package was complete.

On May 7, 1992, William L. MacDowell, Chief, Regulation Development

Section-Region 5, EPA, sent a letter to Robert Hodanbosi, of the OEPA,

detailing issues EPA had identified in the State's September 9, 1991

submittal. On March 19, 1993, the State responded with a subsequent

submittal which addressed the above mentioned issues, and included a

Director's Finding and Order governing the operation of selected

boilers at Cincinnati Gas and Electric's Miami Fort facility.

Additional technical information supporting the March 19th submittal

was received from OEPA by EPA on May 18, 1993.

A major issue in the development of the revised submittal involved

the incorporation of the Rough Terrain Diffusion Model (RTDM). The RTDM

is one of many computer models available used to simulate the

dispersion of air pollutants. A ``Model Evaluation and Comparison

Study'' was conducted by the Greater Cincinnati Chamber of Commerce, in

cooperation with the OEPA and EPA Region 5, in order to determine which

model, or combination of models, (Industrial Source Complex (ISC)

Short-term model or the RTDM) was most accurate in predicting SO2

concentrations in Hamilton County. This study was conducted in

accordance with a protocol that EPA agreed to on October 31, 1990, and

in accordance with EPA document entitled ``Interim Procedures for

Evaluating Air Quality Models (Revised),'' 1984. Based on the results

of the study, EPA approved the RTDM model for use in modeling sulfur

dioxide sources in Hamilton County in a June 9, 1992, letter from David

Kee, Director, Air and Radiation Division, to Robert Hodanbosi, Chief,

Division of Air Pollution Control. The model/monitor comparison study

is discussed more completely in the Technical Support Document

associated with this document.

II. Attainment Demonstration

The principal requirement for the Ohio SO2 SIP under section

110, as identified in the SIP deficiency notice, is that the plan

provides sufficient enforceable measures to assure attainment of the

NAAQS for SO2. As noted above, the State provided enforceable

limits in the form of State regulations, supplemented by an

administrative order for one source, along with an air dispersion

modeling analysis which demonstrates that these limits assure

attainment in the Hamilton County area. The modeling techniques used in

the demonstration supporting this revision were based on procedures in

the ``Guideline on Air Quality Models (Revised),'' July 1986, including

``Supplement A,'' July 1987. The modeling methodology is discussed more

fully in the Technical Support Document.

The attainment demonstration incorporated three different air

dispersion models: Industrial Source Complex Short-Term (ISCST),

COMPLEX I (Valley Screen Mode for analyzing intermediate terrain), and

the Rough Terrain Diffusion Model (RTDM). Some basic components of the

modeling methodology are:

Meteorological Data-The ISCST modeling used the most recent five

years of meteorological data while RTDM used one year of meteorological

data collected in Hamilton County.

Rural/Urban Classification-Western Hamilton County sources were

modeled in the Rural mode while sources in the east were modeled using

Urban mode 3.

Emission Inventory-The emission sources used in the modeling

represent maximum short-term operating rates and stack parameters.

Actual operating factors were gathered and used to evaluate annual

SO2 predicted concentrations.

Background Concentrations-The 3-hour, 24-hour, and annual averaging

background concentrations were determined for both the eastern and

western grids. The background values were based on monitoring data and

are considered representative of SO2 concentrations being

contributed from unmodeled sources in the Hamilton County area.

Good Engineering Practice (GEP) stack heights or actual stack

heights, where appropriate, were used in Ohio's modeling in accordance

with EPA guidance. However, a January 22, 1988, remand in a U.S. D.C.

Court of Appeals case involving EPA stack height regulations remains

unresolved1. It is possible that future resolution of this case

will result in the State being required to revise the emission

limitations for the CG&E Miami Fort facility.

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\1\Certain provisions of the July 8, 1985, stack height

regulations were remanded to USEPA in NRDC v. Thomas (D.C. Cir. No.

85-1488 et. al. (January 22, 1988)). These are grandfathering stack

height credits for sources who raise their stacks prior to October

2, 1983, up to the height permitted by GEP formula height (40 CFR

51.100(KK)(2)), dispersion credit for sources originally designed

and constructed with merged or multi-flue stacks (40 CFR

51.100(hh)(2)(ii)(A)), and grandfathering credit for refined

(H+1.5L) formula height for sources unable to show reliance on the

original (2.5H) formula (40 CFR 51.100(ii)(2)).

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In the modeling for the attainment demonstration for Hamilton

County, the State did not use the most recent version of the Industrial

Source Complex model, known as ISC2. The ISC2 version of the Industrial

Source Complex model was released after the State submitted its SIP to

EPA, and well after the completion of the ISCST modeling used to

determine appropriate SIP limits. Consequently, EPA proposes to accept

analysis under the older model for the purpose of this SIP review.

However, acceptance of the ISCST analysis for this reason should not

apply to any other analysis of this area to support any future

regulatory action.

Although the majority of the attainment demonstration was comprised

of output from ISCST, several areas of Hamilton County were modeled

using RTDM. The RTDM modeling was performed in accordance with the EPA

approved ``Model Evaluation and Comparison Study'' described earlier.

The modeling demonstration accompanying the SIP revision submittal

incorporated dispersion modeling output from the ISCST model in

combination with RTDM.

The issues identified in the May 7, 1992, letter from William L.

MacDowell, Chief, Regulation Development Section-Region 5, EPA to

Robert Hodanbosi, of the OEPA, regarding the September 9, 1991

submittal, needed to be resolved before EPA could approve the SIP

revisions. One of those issues involved modeled SO2 violations

near the Joseph E. Seagram and Sons, Inc. (Seagram's) facility in

Dearborn County, Indiana. These modeled violations were primarily due

to emissions from the Seagrams facility in Indiana. However, CG&E,

located in Hamilton County, Ohio, contributed to the critical

concentration in that area.

In response to the modeled violation, a commitment has been

obtained from Seagram's, formalized in a letter from Seagrams to both

the OEPA and the Indiana Department of Environmental Management, dated

September 1, 1992, agreeing to not operate its two boilers

simultaneously on sulfur-bearing fuels without written permission from

both State Agencies. Utilizing this commitment, the OEPA submitted

supplementary modeling which demonstrated that areas near Seagrams, in

Indiana, did not exceed the sulfur dioxide NAAQS. However, in order for

the Seagrams limit to be federally enforceable, it must be incorporated

into the Indiana sulfur dioxide SIP. Therefore, the Hamilton County

SO2 SIP revision will be approved if the Seagrams commitment,

described above, is adopted into the Indiana SO2 SIP within one

year from the date of publication of the Hamilton County SO2 SIP

revision final rulemaking. This issue and other issues addressed by

Ohio's submittals of March 19, 1993, and May 18, 1993, are discussed in

detail in the Technical Support Document.

Based on the foregoing, EPA concludes that the results from Ohio's

modeling demonstration, utilizing the ISCST and RTDM air dispersion

models, show that when the applicable emission limits and other

restrictions are imposed, attainment of the NAAQS for SO2 will be

demonstrated in and around Hamilton County.

III. Compliance

The general compliance determination method denoted in OAC 3745-18-

04(D)(7), which applies specifically to Hamilton County, utilizes stack

gas sampling using Methods 1 through 4 and 6, 6A, 6B, or 6C, as

specified in 40 CFR 60.46, for any fuel burning equipment. Additional

compliance monitoring is required under OAC 3745-18-04(D)(8), which, on

a source-specific basis, requires either daily or weekly coal sampling.

EPA has determined, based on guidance contained in the ``General

preamble for future proposed rulemakings,'' published in the Federal

Register on April 16, 1992 (57 FR 13498), that compliance methods 1

through 4, 6, 6A, 6B, and 6C, in conjunction with regular fuel

sampling, provide for continuous SO2 compliance monitoring.

Additionally, documentation criteria listed in OAC 3745-18-04(I)

requires sources subject to the Hamilton County emission limits to

document and retain information needed to demonstrate compliance with

applicable emission limits, emission tracking requirements, and/or

operating limits.

IV. Proposed Action

Section 110(a)(2) of the Clean Air Act contains general

requirements for implementation plans submitted by a State. These are

requirements which apply to all SIPs submitted by a State including

attainment area plans, such as the plan for Hamilton County. A

fundamental requirement of this section is that each plan must include

enforceable emission limitations and other techniques necessary to meet

the applicable requirements of the Clean Air Act. EPA has determined

that the emission limits and control measures listed in the SO2

SIP revision for Hamilton County, when fully implemented, will be

enforceable, and, will provide for attainment of the NAAQS for

SO2, and thus satisfy the applicable requirements. As stated

above, this determination is contingent upon the Seagrams limits being

incorporated into the Indiana SO2 SIP and, as a result, made

federally enforceable.

Therefore, EPA is proposing to conditionally approve revisions to

Ohio Administrative Code (OAC) rules 3745-18-03, 3745-18-04, and 3745-

18-37. The OAC rules 3745-18-03 Attainment Dates and Compliance Time

Schedules provide specific time schedules for sources receiving revised

emission limits to implement necessary changes and demonstrate

compliance. The OAC rules 3745-18-04 Measurement Methods and Procedures

specify the compliance determination methodologies for sources

receiving revised emission limits. The OAC rules 3745-18-37 Hamilton

County Emission Limits amend the sulfur dioxide emission limits for

Hamilton County. EPA is also proposing to approve the Director's

Findings and Order containing a fuel quality limit for select sources

at Cincinnati Gas and Electric's Miami Fort facility.

Under section 110(k)(4), pertaining to conditional approval, the

SIP elements regarding the Seagrams limits must be adopted by the State

of Indiana, by a date not later than one year after the date of

approval of the Hamilton County, Ohio SIP revision. In addition, the

adopting State must submit these rules to EPA within a reasonable time

after such adoption. In this case, if the State of Indiana fails to

adopt or submit the necessary rules to EPA within the required time

frame (one year from the date of final approval of the Hamilton County,

Ohio SO2 SIP revision), this approval would become a disapproval

upon USEPA notification of Ohio by letter. The EPA subsequently would

publish a notice announcing this action in the Federal Register. If the

State of Indiana adopts and submits the rule within the above

timeframe, the conditionally approved rules would remain a part of the

SIP pending final action on the new submittal.

Public comments are solicited on the requested SIP revision and on

EPA's proposal to conditionally approve. Public comments received by

February 28, 1994 will be considered in the development of EPA's final

rulemaking action.

Nothing in this action should be construed as permitting, allowing

or establishing a precedent for any future request for revision to any

SIP. EPA shall consider each request for revision to the SIP in light

of specific technical, economic, and environmental factors and in

relation to relevant statutory and regulatory requirements.

This action has been classified as a Table 2 action by the Regional

Administrator under the procedures published in the Federal Register on

January 19, 1989 (54 FR 2214-2225). On January 6, 1989, the Office of

Management and Budget (OMB) waived Table 2 and 3 SIP revisions (54 FR

2222) from the requirements of section 3 of Executive Order 12866 for a

period of 2 years. EPA has submitted a request for a permanent waiver

for Table 2 and 3 SIP revisions. OMB has agreed to continue the waiver

until such time as it rules on EPA's request. This request continues in

effect under Executive Order 12866 which superseded Executive Order

12291 on September 30, 1993.

Under the Regulatory Flexibility Act, 5 U.S.C. 600 et seq., EPA

must prepare a regulatory flexibility analysis assessing the impact of

any proposed or final rule on small entities. (5 U.S.C. 603 and 604.)

Alternatively, EPA may certify that the rule will not have a

significant impact on a substantial number of small entities. Small

entities include small businesses, small not-for-profit enterprises,

and government entities with jurisdiction over populations of less than

50,000.

Conditional SIP approvals under section 110 and subchapter I, part

D of the Clean Air Act do not create any new requirements, but simply

approve requirements that the State is already imposing.

If the conditional approval is converted to a disapproval under

section 110(k), based on a State's failure to meet the commitment, it

will not affect any existing state requirements applicable to small

entities. Federal disapproval of the state submittal does not affect

its state-enforceability. Moreover, EPA's disapproval of the submittal

does not impose a new Federal requirement. Therefore, EPA certifies

that this disapproval action does not have a significant impact on a

substantial number of small entities because itdoes not remove existing

state requirements nor does it substitute a new Federal requirement.

Therefore, because the Federal SIP approval does not impose any new

requirements, I certify that it does not have a significant impact on

any small entities affected. Moreover, due to the nature of the

Federal-State relationship under the Act, preparation of a regulatory

flexibility analysis would constitute Federal inquiry into the economic

reasonableness of state action. The Act forbids EPA to base its actions

concerning SIPS on such grounds. Union Electric Co. v. EPA, 427 U.S.

246, (1976); 42 U.S.C. 7410(a)(2).

List of Subjects in 40 CFR Part 52

Environmental protection, Air pollution control, Incorporation by

reference, Reporting and recordkeeping requirements, Sulfur oxides.

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

Dated: December 29, 1993.

Valdas V. Adamkus,

Regional Administrator.

[FR Doc. 94-1737 Filed 1-26-94; 8:45 am]

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