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Oklahoma SIP: Visibility Protection Plan Summary

Regulatory Text:
Oklahoma Visibility Protection Plan Summary 

Federal Register Dates:
     November 8, 1999   Proposed rule, 64 FR 60759.
     November 8, 1999   Direct final rule, 64 FR 60683.

Purpose of Plan:  For Oklahoma SIP to meet the requirements of Section 169A of the Federal Clean Air Act which requires visibility protection for mandatory Class I Federal areas where EPA has determined that visibility is an important value.

Area Covered:  Wichita Mountains National Wildlife Refuge in Comanche County near Fort Sill Military Reservation.  Currently, there are no integral vistas (40 CFR 51.304) in Oklahoma.

Type of Pollutant:  All

Federal Requirements:  Section 169A of the Federal Clean Air Act requires visibility protection for mandatory Class I Federal areas where EPA has determined that visibility is an important value.  Mandatory Class I Federal areas are defined as certain national parks, wilderness areas, and international parks, as described in section 162(a) of the Act.  Mandatory Class I Federal areas in each State are listed in 40 CFR Part 81, Subpart D -- Identification of Mandatory Class I Federal Areas Where Visibility is an Important Value.  The Federal regulations that state and local agencies must meet to implement Section 169A of the Federal Clean Air Act are found in 40 CFR 51, Subpart P, Visibility Protection.

State Submittal:  The Governor of Oklahoma submitted to EPA a revised Oklahoma Visibility Protection Plan on June 18, 1990.

EPA Approval:  The EPA approved the Oklahoma Visibility Protection Plan submitted June 18, 1990, in a direct final Federal Register action published November 8, 1999 (64 FR 60683).  This Plan replaced the EPA disapproval of the previous Oklahoma visibility plan and the resulting Federal Implementation Plan (FIP) published in the Federal Register on June 24, 1986 (51 FR 22937), and November 24, 1987 (52 FR 45137), and codified in 40 CFR 52.1933.  See the November 8, 1999, Federal Register, for more background information.

Summary of Oklahoma Visibility Protection Plan approved by EPA November 8, 1999 (52 FR 45137):

      Part I  Visibility New Source Review.  The Oklahoma SIP-approved new source review (NSR)regulations, as approved by EPA November 8, 1999 (64 FR 60683), meet the Federal NSR requirements of 40 CFR 51, Subpart P, Visibility Protection.

      Part I  Visibility Monitoring Strategy.  Section 8, Visibility Monitoring Program in the 1990 Plan, provides that the Oklahoma State Department of Health will monitor the background visibility conditions in the mandatory Class I Federal area by monthly review of local airport visibility data as collected by the National Weather Service in Lawton, Oklahoma, airport located 22 miles southeast of the Wichita Mountains Wilderness and the Fort Sill Military Reservation airport located 19 miles southeast of the Wilderness in almost flat terrain.  EPA approved the use of the airport visibility data as representative of the conditions in the Class I area.  The 1990 Plan includes an emission inventory of sources within a 55-kilometers radius from the Wichita Mountains Refuge.  The Oklahoma State Department of Health determined that there are no existing sources within a 55-kilometer radius from the Refuge with emissions that would significantly impact upon the Federal Class I area, and based on the record EPA agreed with the State’s determination.

      Part II  Visibility Long-Term Strategy and Implementation Control Strategies.  The State of Oklahoma has satisfied the visibility general plan requirements of 40 CFR 51.302.  The FLM has been afforded the opportunity to identify visibility impairment and to recommend elements for inclusion in the long-term strategy.  The State has accorded the FLM opportunities to participate and comment on its visibility SIP revision.  Comments by the FLM were submitted to the State during the State’s public notice period, and they were considered by the State and incorporated where applicable.  The State has committed in the SIP to consult continually with the FLM on the review and implementation of the visibility program.  

      The 1990 Plan contains the following provisions of the Part II Visibility Protection Plan requirements:  

1) a determination that there is no existing visibility impairment that is reasonably attributable to specific sources;

2) a discussion of the SIP elements and how each element of the plan relates to the national goal; and

3) a long-term (10-15 years) strategy.  

      Since no existing reasonably attributable impairment has been identified, all elements of the plan are intended to prevent future impairment of visibility.  If existing reasonably attributable impairment is later identified, the State will revise its plan to remedy the impairment.  The Part II revision consists of a narrative only, no regulatory revisions.  Currently, there are no integral vistas in Oklahoma.

      The Oklahoma visibility long-term strategy section included the following:

1) coordination with the FLM;

2) consideration of the six required factors for a long-term strategy;

3) a provision for the review of the impact of new sources, and discussion of current visibility monitoring efforts; and

4) provisions for periodic review (i.e., every three years) of the plan, which review must include consultation with the FLM and a report to the public and to EPA on progress toward the national goal.

      The Oklahoma Plan meets all visibility implementation control strategies requirements of 40 CFR 51.302 and visibility long-term strategy requirements of 40 CFR 51.306.

State regulations approved as part of the Oklahoma Visibility Plan

      Oklahoma Regulation 1.4, Air Resources Management Permits Required,  Regulation 1.4.4, Major Sources -- Prevention of Significant Deterioration (PSD) Requirements for Attainment Areas, specifically section 1.4.4(f), Air quality impact evaluation, and section 1.4.4(g), Source Impacting Class I areas.