VOL. 59, No. 53
ENVIRONMENTAL PROTECTION AGENCY (EPA)
40 CFR Parts 52 and 81
Designation of Areas for Air Quality Planning Purposes; Ohio
59 FR 12886
DATE: Friday, March 18, 1994
ACTION: Proposed rule.
SUMMARY: On August 6, 1992, USEPA received maintenance plans and a request from the Ohio Environmental Protection Agency (OEPA) for redesignation of Coshocton, Gallia, Morgan, and Washington Counties from nonattainment to attainment for sulfur dioxide (SO2). USEPA is proposing to approve the maintenance plans and redesignation request for Morgan and Washington Counties and deferring action with respect to the submittal for Coshocton and Gallia Counties.
DATES: Comments on the request and the proposed USEPA action must be received by April 18, 1994.
ADDRESSES: Written comments should be addressed to: William MacDowell, Chief, Regulation Development Section, Air Enforcement Branch (AE-17J), U.S. Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, Illinois 60604.
Copies of the materials submitted by the State and the February 9, 1994, technical support document are available at the following addresses for review: (It is recommended that you telephone John Summerhays at (312) 886-6067, before visiting the Region 5 office.) U.S. Environmental Protection Agency (AE-17J), Region 5, Air Enforcement Branch, 77 West Jackson Blvd., Chicago, Illinois 60604-3590.
FOR FURTHER INFORMATION CONTACT: John Summerhays, Air Enforcement Branch (AE-17J), U.S. Environmental Protection Agency, Region 5, 77 West Jackson Boulevard, Chicago, Illinois 60604-3590, (312) 886-6067
Under section 107(d) of the Clean Air Act, as amended in 1977, USEPA promulgated designations of whether each area in the country was attaining the National Ambient Air Quality Standards (NAAQS). (See Federal Register of March 3, 1978 (43 FR 8962), and October 5, 1978 (43 FR 45993).) Included among these designations were nonattainment designations for SO2 for Coshocton, Gallia, Morgan, and Washington Counties in Ohio. The Clean Air Act Amendments of 1990 provided for both continuation of preexisting SO2 designations and new criteria and procedures for redesignations. These criteria are discussed in the "General Preamble for the Implementation of Title I of the Clean Air Act Amendments of 1990," published at 57 FR 13498 on April 16, 1992, and in a USEPA memorandum from John Seitz to the Regional Air Division Directors entitled "Redesignation and Maintenance Plan Requirements for Nonattainment Areas," dated September 4, 1992.
On August 6, 1992, USEPA received a submittal from the Ohio Environmental Protection Agency (OEPA) requesting redesignation of Coshocton, Gallia, Morgan, and Washington Counties from nonattainment to attainment for SO2. This submittal also included air quality data summaries and daily coal sampling data for the four major power plants in the four counties. A subsequent submittal dated July 30, 1993, provided stack test data for one of these facilities and indicated that stack test data for the other facilities would be sent shortly.
II. Review of State Submittal
Section 107(d)(3)(E) of the amended Act provides that redesignations of areas from nonattainment to attainment can be approved only if five criteria are met:
(i) USEPA determines that the area has attained the NAAQS;
(ii) USEPA has fully approved the relevant implementation plan;
(iii) USEPA determines that the improvement in air quality is due to permanent and enforceable reductions in emissions resulting from implementation of the applicable implementation plan and applicable Federal air pollutant control regulations and other permanent and enforceable reductions;
(iv) USEPA has fully approved a maintenance plan for the area as meeting the requirements of Section 175A; and
(v) the State containing such area has met all requirements applicable to the area under Section 110 and part D.
These criteria and the extent to which these criteria are satisfied are discussed individually in the following subsections.
A. Attainment of the SO2 NAAQS
Air quality standards for SO2 have been set for three averaging times: annual (at a level of 80 micrograms per cubic meter (mug/m3)), 24-hour (at a level of 365 mug/m3), and 3-hour (at a level of 1300 mug/m3). Two types of information are used to assess whether these standards are met: ambient monitoring data, and dispersion modeling estimates. Monitoring is generally conducted at too few locations to fully represent air quality near significant SO2 sources. Therefore, it is common to rely more on dispersion modeling results in assessing areas' attainment status. Indeed, in 1976, for much of Ohio including the four counties addressed in Ohio's redesignation request, USEPA promulgated emissions limits found through modeling to be necessary to assure attainment. The nonattainment designations promulgated in 1978 for these four counties reflected comparison of the sources' emissions with these promulgated limits. (See Federal Register notices cited above.) Conversely, a redesignation of these four counties to attainment must be supported by modeling information as well as by any available monitoring information. Provided that the source mix in the areas remains largely unchanged, the modeling information may reflect the modeling underlying the applicable limits (whether approved State limits or federally promulgated limits). This would involve the State demonstrating attainment by showing that emissions levels are within limits that USEPA found would assure attainment. In the typical case involving a relatively small number of sources with explicit limits that dominate ambient concentrations, such a demonstration would be required to show compliance for all such sources.
USEPA has examined ambient monitoring data from the Air Information Retrieval System (AIRS) data base for 1980 to 1992 in the four counties. These data indicate exceedance of an SO2 standard on only one occasion, an exceedance in 1991 of the 3-hour average standard in Morgan County. The 3-hour and 24-hour average standards are not violated unless 2 or more exceedances occur in a year. Therefore, no SO2 violations were recorded in the four county region during the 13 years examined.
The submittal of fuel quality data to support the State's request raises several issues. The first issue is whether fuel quality data may be used to indicate attainment status, even though stack testing is the compliance test method USEPA has approved for sources subject to State Implementation Plan (SIP) limits and promulgated for sources subject to Federal Implementation Plan (FIP) limits. Since the purpose of this review is to assess air quality and not individual source compliance, USEPA judges the use of fuel quality data to be appropriate. Indeed, fuel quality data in conjunction with atmospheric dispersion analyses (in this case previously completed analyses) can provide information both for a broader set of times than stack testing and for a broader set of locations than ambient monitoring.
An associated issue involves appropriate averaging times. The State's rules provide for 30-day averaging of fuel quality data, and USEPA has adopted a policy that gives enforcement priority to sources violating applicable limits on a 30-day average basis. Nevertheless, for purposes of reviewing whether the four counties are attaining the 24-hour average SO2 standards, daily fuel quality information was used. Fuel quality data showing daily compliance with emissions limits which modeling showed would assure attainment is considered evidence of attainment of both the annual average and the 24-hour average standards. For the 3-hour standard, fuel quality data indicating continuous compliance on a 24-hour average basis is to be supplemented by stack test results demonstrating compliance on this shorter averaging time.
An additional issue pertaining to the use of fuel quality data involves the appropriate conversion factor from fuel sulfur content to SO2 emissions. Ohio's rules provide a conversion factor for coal of 1.9 pounds of SO2 emissions per pound of sulfur in fuel. However, USEPA currently believes that 1.95 pounds of SO2 are emitted per pound of sulfur in coal. USEPA's review of the State's fuel quality information used this slightly higher conversion factor.
In support of its redesignation request, the State provided available 1989 to 1991 daily coal quality data for Ohio Valley Electric Corporation's Kyger Creek Station (in Gallia County), Ohio Power Company's Gavin Station (also in Gallia County) and Muskingham River Station (in Morgan and Washington Counties), and Columbus and Southern Ohio Electric Company's Conesville Station (in Coshocton County). The State also provided results of multiple stack tests at the Muskingham River Station, and committed to send results of recently completed stack tests for the other plants in the near future. Although three of the four counties also include at least one industrial source subject to source-specific emissions limits, these sources are not located in the portion of the county designated nonattainment and do not significantly affect nonattainment area air quality.
The fuel quality data submitted by the State indicate no recent violations of air quality standards in the four counties. The Kyger Creek data showed no exceedances of the applicable limit on any day during the 3 years. The Gavin data showed exceedances for a single boiler on three occasions in 1989, but no exceedances in 1990 or 1991. The Muskingham River data showed numerous exceedances through May 1989, but then during the subsequent 2 1/2 years only one occasion of coal for one boiler exceeding the applicable limit. On this occasion the fuel quality for other boilers was enough below the applicable limit to compensate for the exceedance at the one boiler, such that use of the actual fuel qualities in the modeling analysis underlying the approved SIP would indicate attainment. Finally, the Conesville data indicated an exceedance at all boilers in April 1989, but no exceedances in the subsequent 2 1/2 years. These periods of compliance, reflecting the most recent available data, provide sufficient basis for USEPA to conclude that these areas are now attaining annual average and 24-hour average air quality standards.
The fuel quality data, in conjunction with stack test data for the Muskingham River Station, also indicate attainment of the 3-hour average standard in Morgan and Washington Counties. USEPA has not received stack test data for Coshocton or Gallia Counties, and has not evaluated whether these counties are attaining the 3-hour standard.
B. Fully Approved Implementation Plan
The second criterion for redesignation to attainment, given in section 107(d)(3)(E)(ii), is that the plan be fully approved under section 110(k). The plan for the Morgan and Washington Counties nonattainment area was approved on May 20, 1988 (53 FR 18087). Although this approval was granted under section 110(a)(2) rather than section 110(k), section 110(a)(2) was the predecessor of and contained similar provisions as section 110(k) prior to the enactment of section 110(k) in the Clean Air Act Amendments of 1990. Thus, USEPA views approval of a SIP under section 110(a)(2) prior to the enactment of the 1990 amendments as sufficient to satisfy the criterion of section 107(d)(3)(E)(ii).
The key elements of the plans for Coshocton and Gallia Counties are Federal Implementation Plan (FIP) limits promulgated under section 110(c). Based on questions as to whether such plans satisfy the requirements of section 107(d)(3)(E)(ii), USEPA is deferring action on Ohio's request for these two counties.
C. Permanent and Enforceable Emission Reductions
The third criterion for redesignation to attainment is that the improvement be attributable to permanent and enforceable emissions reductions. For SO2, this criterion could be satisfied, for example, by showing that the key sources have switched to fuels with sufficiently lower sulfur content to meet permanent, federally enforceable fuel quality limits that provide for attainment. For the four counties subject to the State's redesignation request, this criterion is met because the air quality improvement is due to sources switching to coal supplies with reduced sulfur content in order to meet enforceable limits.
D. Maintenance Plan
The fourth criterion is that USEPA has fully approved a maintenance plan pursuant to section 175A. Section 175A requires a plan that assures maintenance of the air quality standard for at least 10 years beyond the date of redesignation, and includes contingency measures as necessary to assure prompt correction of any violations. USEPA has published guidance that for SO2, contingency measure requirements under section 172(c)(9) (for SIPs) may be satisfied by a State having an aggressive program for identifying and resolving any instances of sources not complying with limits established to assure attainment. (See 57 FR 13547.) Such an enforcement program would also satisfy SO2 contingency measure requirements under section 175A. Ohio submitted a maintenance plan in conjunction with its redesignation request. This action addresses Ohio's maintenance plan as well as its redesignation request.
The maintenance plan submitted by Ohio includes federally mandated reductions in diesel fuel sulfur content and the expected power plant emission reductions due to acid rain requirements under Title IV of the Clean Air Act. In addition, Ohio maintains active tracking of the compliance status of sources and commences enforcement action upon identifying violators, thereby assuring prompt correction of any violations of the air quality standards attributable to the existing set of sources. Furthermore, for any new sources with the potential to cause air quality standard violations, Federal requirements for the Prevention of Significant Deterioration include provisions to prevent new violations of the standard. Therefore, USEPA considers the requirements of section 175A met, and is proposing to approve Ohio's maintenance plan for SO2 for Morgan and Washington Counties. (For reasons stated previously, USEPA is not proposing action today with respect to the requests for Coshocton and Gallia Counties, and accordingly is also not proposing action on the maintenance plan for these counties.) If the maintenance plan for Morgan and Washington Counties is approved as proposed, Ohio would then satisfy the fourth criterion for redesignation of these counties to attainment.
E. Requirements Under Section 110 and Part D
The fifth criterion is that all requirements under section 110 and part D of Title I have been met. USEPA approved the SIP for the Morgan and Washington County nonattainment area on May 20, 1988, at 53 FR 18087. Accordingly, the fifth criterion is satisfied for this area. USEPA is not undertaking rulemaking today on whether the federally promulgated limits satisfy this criterion for Coshocton or Gallia Counties.
III. Summary of Action
USEPA has reviewed the State's submittals and other related material and has concluded that the maintenance plan and redesignation request for Morgan and Washington Counties satisfy the applicable criteria for approval. Consequently, USEPA proposes to approve the maintenance plan for SO2 for Morgan and Washington Counties, and to redesignate these two counties to attainment. USEPA is deferring action with respect to Ohio's maintenance plans and redesignation requests for Coshocton and Gallia Counties.
Under the Regulatory Flexibility Act, 5 U.S.C. 600 et seq., USEPA 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, USEPA may certify that the rule will not have a significant impact on a substantial number of small entities. Small entities include small business, small not-for-profit enterprises, and government entities with jurisdiction over populations of less than 50,000.
Redesignation of an area either to nonattainment or to attainment does not impose any new requirements on small entities. Redesignation is an action that affects the status of a geographical area and does not impose any regulatory requirements on sources. The Administrator certifies that the approval of the redesignation request will not affect a substantial number of small entities.
Nothing in this action should be construed as permitting, allowing or establishing a precedent for any future request redesignations. Each redesignation request shall be considered separately 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 Two action by the Regional Administrator under the procedures published in the Federal Register on January 19, 1989 (54 FR 2214-2225), based on revised SIP processing review tables approved by the Acting Assistant Administrator for Air and Radiation on October 4, 1993 (Michael Shapiro's memorandum to Regional Administrators). On January 6, 1989, the Office of Management and Budget waived Tables Two and Three SIP revisions (54 FR 222) from the requirements of section 3 of Executive Order 12291 for a period of 2 years. USEPA has submitted a request for a permanent waiver for Table 2 and Table 3 SIP revisions. OMB has agreed to continue the temporary waiver until such time as it rules on USEPA's request. This request continued in effect under Executive Order 12866, which superseded Executive Order 12291 on September 30, 1993.
Authority: 42 U.S.C. 7401-7671q.
Dated: February 18, 1994.
David A. Ullrich, Acting Regional Administrator.
[FR Doc. 94-6456 Filed 3-17-94; 8:45 am]
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