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Ozone Implementation

Modification of the Ozone Monitoring Season; Wisconsin

Information provided for informational purposes onlyNote: EPA no longer updates this information, but it may be useful as a reference or resource.

[Federal Register: March 3, 1995]


40 CFR Part 58

[WI51-01-6828; FRL-5158-3]

Modification of the Ozone Monitoring Season; Wisconsin

AGENCY: United States Environmental Protection Agency (USEPA).

ACTION: Final rule.

SUMMARY: This final rule contains revisions to part 58 of chapter 1 of title 40 of the Code of Federal Regulations (CFR), appendix D, the Ozone Monitoring Season By State table in section 2.5. The revisions change Wisconsin's ozone monitoring season to April 15 through October 15.

EFFECTIVE DATE: March 3, 1995.

ADDRESSES: Copies of documents relevant to this action are available for inspection at the following address: United States Environmental Protection Agency, Region 5, Air and Radiation Division, 77 West Jackson Boulevard, Chicago, Illinois, 60604. Telephone Jacqueline Nwia at (312) 886-6081 before visiting the Region 5 Office.

FOR FURTHER INFORMATION CONTACT: Jacqueline Nwia, Regulation Development Section, U.S. Environmental Protection Agency, Region 5, Air Toxics and Radiation [[Page 11908]] Branch, 77 West Jackson Boulevard, Chicago, Illinois, 60604. Telephone (312) 886-6081.


I. Background

On January 11, 1980 (45 FR 2319), the USEPA approved, into the Wisconsin SIP, revisions to Wisconsin rule NR 154.01-Definitions, which set forth the ozone season for Wisconsin as the period each year from May 1 through September 30. This action was codified in 40 CFR part 52, Sec. 52.2570(c)(13).
On April 4, 1980, the USEPA approved a waiver for ozone monitoring at State and Local Ambient Monitoring Stations (SLAMS) from October 16 to April 14 with the exception of National Ambient Monitoring Stations (NAMS) sites required in the southeast Wisconsin air quality control region, which would continue to monitor for the entire year as recommended in the USEPA's Guideline for the Implementation of Ambient Air Monitoring (EPA 450/4-79-038). This approval was in the form of a letter from the Regional Administrator to the Director of Wisconsin's Department of Natural Resources (WDNR) Bureau of Air Management. See the USEPA guidance entitled Guideline on Modification to Monitoring Seasons for Ozone, March 1990, prepared by the Technical Support Division of Office of Air Quality Planning and Standards. On March 19, 1986 (51 FR 9582), the USEPA promulgated revisions to 40 CFR part 58, appendix D, which were needed to meet changing air monitoring program requirements. These revisions included the addition of the Ozone Monitoring Season By State table in section 2.5, of appendix D. This table listed the Wisconsin ozone monitoring season as beginning on April 1 and ending on October 31. This is the ozone season currently reflected in the Aerometric Information Retrieval System (AIRS) for Wisconsin.

II. Review

Since AIRS extracts the ozone monitoring season from appendix D, April 1 through October 31 is reflected in AIRS for Wisconsin. Consequently, this ozone season is used in the calculation of the number of expected exceedances. Since Wisconsin SLAMS only monitor from April 15 through October 15, there are 29 non-monitored days. AIRS views this non-monitored situation as missing data. This has the effect of increasing the exceedance estimate, if any exceedances are observed. AIRS assigns the same ozone season to all SLAMS, NAMS and Special Purpose Monitoring Stations (SPMS) monitors in a State or county. AIRS does not have the capability to define a separate ozone season for individual monitors. Further, 40 CFR part 58, appendix D does not distinguish ozone seasons by monitor type, but defines an ozone season for all monitor types.
Since the shorter ozone season was already approved by the Regional Administrator in 1980 for SLAMS, an analysis for these monitors is not required. The 1980 waiver, however, did not apply to NAMS monitors. Therefore, as recommended by the Guideline on Modification to Monitoring Seasons for Ozone, Technical Support Division Office of Air Quality Planning and Standards, March 1990, the USEPA reviewed the ozone monitoring data for the entire State to determine whether the 1980 waiver may be extended to NAMS.
The guidance states that the potential for ozone exceedances, and, consequently, ozone season reductions can be determined using historical ozone monitoring data. A review of historical ozone data for this purpose must be based on 5 years of the most recent data, in order to ensure that both favorable and unfavorable conditions are represented. The guidance allows reduction in monitoring for months without 1-hour ozone concentrations exceeding 0.10 ppm during the most recent 5 years.
The most recent 5 years, 1988-1993, of ambient ozone data (AIRS AMP215 and AMP355 Standard Reports), demonstrates that there have been no exceedances of the ozone National Ambient Air Quality Standard in the time periods April 1 through April 14 and October 16 through October 31 for any of the NAMS monitors in the State. The highest ozone value recorded at a NAMS between April 1 and April 14 was 0.08 parts per million (ppm) in Ozaukee county (55-089-0005) in 1991. The highest ozone value recorded at a NAMS between October 16 and October 31 was 0.076 ppm which occurred in 1989 in Columbia county (55-021-0015) and Ozaukee county (55-089-0005), both of which fall below the 0.10 ppm recommended limit. See Guideline on Modification to Monitoring Seasons for Ozone, Technical Support Division Office of Air Quality Planning and Standards, March 1990, p. 5.
The relevant data demonstrates that no concentrations above 0.10 ppm were recorded during April 1-April 14 or October 16-October 31. Consequently, the test of 5 years of data without any concentrations above the recommended limit of 0.10 ppm has been satisfied. In addition, it should be noted that the ozone season as it applies to Wisconsin's rules and regulations will not change with this revision. The ozone season approved as part of the Wisconsin SIP, in Rule 154.01 Definitions, is the period from May 1 through September 30 and will continue to be so.
The modified ozone monitoring season will apply to future monitoring efforts at SLAMS and NAMS unless otherwise revised.

III. Action

After reviewing 5 years worth of Wisconsin ozone monitoring data, we find that the change in ozone monitoring season in Wisconsin complies with all applicable requirements of the Clean Air Act (Act) and USEPA policy and regulations concerning such revisions. Pursuant to 40 CFR 58.13(a)(3), the Regional Administrator has the authority to exempt periods or seasons from consecutive hourly averages for continuous SLAMS analyzers.
The USEPA is revising Wisconsin's ozone monitoring season in 40 CFR part 58, appendix D, section 2.5 to April 15 through October 15 of each year for all monitor types.
Because USEPA considers this action noncontroversial and routine, we are approving it without prior proposal. The action will become effective on March 3, 1995.
Under section 307(b)(1) of the Act, 42 U.S.C. 7607(b)(1), petitions for judicial review of this action must be filed in the United States Court of Appeals for the appropriate circuit by May 2, 1995. Filing a petition for reconsideration by the Administrator of this final rule does not affect the finality of this rule for the purposes of judicial review nor does it extend the time within which a petition for judicial review may be filed, and shall not postpone the effectiveness of such rule or action. This action may not be challenged later in proceedings to enforce its requirements. See section 307(b)(2) of the Act, 42 U.S.C. 7607(b)(2).
Under the Regulatory Flexibility Act, 5 U.S.C. 600 et seq., the 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, the USEPA 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. [[Page 11909]]
This action does not create any new requirements. Therefore, I certify that it does not have a significant impact on small entities.

List of Subjects in 40 CFR Part 58

Environmental protection, Air pollution control, Intergovernmental relations.

Dated: February 9, 1995.
David A. Ullrich,
Acting Regional Administrator.

40 CFR part 58, appendix D is amended as follows:


  1. The authority citation for part 58 continues to read as follows: Authority: 42 U.S.C. 7410, 7601(a), 7613, and 7619.

    Appendix D--[Amended]

    2. In section 2.5 of appendix D, the table is amended by revising the entry for Wisconsin to read as follows:

    Appendix D--Network Design for State and Local Air Monitoring Stations (SLAMS) and National Air Monitoring Stations (NAMS) and Photochemical Assessment Monitoring Stations (PAMS)

    • * * * *
      2.5 * * *

    State Begin month End month
                              *    *    *    *    *                         
    Wisconsin.............. April 15............... October 15.
                              *    *    *    *    *                         

    • * * * *
      [FR Doc. 95-5028 Filed 3-2-95; 8:45 am] BILLING CODE 6560-50-P

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