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40 CFR Parts 52 and 81
[MO11-1-5369; FRL-4093-3]

Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality Planning Purposes; State of Missouri

AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.

SUMMARY: Ambient air quality data for the period 1989 through 1991 indicate that the Kansas City ozone nonattainment area has attained the National Ambient Air Quality Standard (NAAQS) for ozone. Therefore, in accordance with the Clean Air Act Amendments of 1990, the state of Missouri has submitted an ozone maintenance plan which projects continued attainment of the ozone standard in the Kansas City area, and has requested redesignation of the area to attainment. EPA is proposing to approve the Kansas City ozone maintenance plan as a revision to the Air Pollution Control State Implementation Plan (SIP) for the state of Missouri. In conjunction with the maintenance plan, EPA is also proposing to approve Missouri's request to redesignate the Kansas City area to attainment with respect to the ozone NAAQS. In a separate Federal Register notice published today, EPA is also proposing to approve an analogous plan and redesignation request submitted by the Kansas Department of Health and Environment to address the Kansas portion of the ozone nonattainment area.

DATES: Comments must be received by February 14, 1992.

ADDRESSES: Comments should be sent to Larry A. Hacker, Environmental Protection Agency, Region VII, Air Branch, 726 Minnesota Avenue, Kansas City, Kansas 66101. The state submittal and the EPA-prepared technical support document (TSD) are available forpublic review at the above address and at the Missouri Department of Natural Resources, Air Pollution Control Program, Jefferson State Office Building, 205 Jefferson Street, Jefferson City, Missouri 65101.

FOR FURTHER INFORMATION CONTACT: Larry A. Hacker at (913) 551-7020 (FTS 276-7020).


I. Background

The Clean Air Act as amended in 1977 (``the 1977 Act'') required areas failing to meet the ozone NAAQS to develop SIPs with sufficient control measures to expeditiously attain and maintain the standard. The Kansas City metropolitan area (KCMA) was designated under section 107 of the 1977 Act as nonattainment with respect to the ozone NAAQS on March 3, 1978. (The designations for Missouri are codified at 40 CFR 81.326.) The Missouri Department of Natural Resources (MDNR) submitted a Part D ozone attainment SIP on July 2, 1979, which EPA fully approved as meeting the requirements of section 110 and Part D of the 1977 Act. The 1979 SIP projected attainment by December 31, 1982, making the KCMA area a ``nonextension area'' under section 172 of the 1977 Clean Air Act. Although the KCMA appeared to have met the ozone standard by the end of 1982, additional violations occurred in 1983 and 1984. On February 20, 1985, EPA notified the Governor of Missouri that the SIP was substantially inadequate to attain the ozone NAAQS (50 FR 26198).

In response to the SIP call, MDNR submitted a revised ozone control strategy on May 26, 1986, which demonstrated attainment by December 31, 1987. EPA proposed to approved the revised SIP on June 30, 1988 (53 FR 24735). At the time of the proposal, EPA believed that the area had achieved the standard, as the 1985 through 1987 air quality data showed attainment. However, ozone violations occurred in June of 1988. Therefore, EPA fully approved the revised control strategy (54 FR 10322 and 54 FR 46232), but deferred action on the attainment demonstration portion of the SIP.

More recently, however, the 1989 through 1991 air quality data show attainment of the ozone NAAQS. Therefore, in an effort to comply with the Clean Air Act Amendments (CAAA) of 1990 (Pub. L. 101-549), and to ensure continued attainment of the standard with an adequate margin of safety, the state submitted an ozone maintenance SIP for the KCMA on October 9, 1991. Accompanying the maintenance SIP are new and amended rules to control certain categories of sources which emit volatile organic compound (VOC) emissions, and the state's request to redesignate the area to attainment with respect to the ozone NAAQS.

II. Evaluation Criteria

Together the Missouri and Kansas submittals meet all applicable requirements of the 1990 Clean Air Act. The EPA rulemaking docket checklist (included with EPA's TSD) provides a listing of applicable approval criteria. However, some of these criteria merit additional discussion which is contained below.

With its submittal of the additional VOC rule actions, Missouri meets the Clean Air Act requirement that the SIP include all reasonably available control measures (RACM) (section 172(c)(1)). The rules are also consistent with EPA policy as outlined in ``Issues Relating to VOC Regulation Cutpoints, Deficiencies, and DeviationsÄClarification to Appendix D of November 24, 1987 Federal Register,'' dated May 25, 1988 (referred to hereafter as the ``Blue Book'').

The Missouri submittal also includes a redesignation request, in which the state demonstrates that the area has fulfilled the redesignation requirements of the amended Act. Section 107(d)(3)(E) of the Act provides specific requirements for redesignating a nonattainment area to attainment:

A. The area must have attained the applicable NAAQS (section 07(d)(3)(E)(i));

B. The area has a fully approved SIP under section 110(k) of the Act (section 107(d)(3)(E)(ii));

C. The air quality improvement must be permanent and enforceable (section 107(d)(3)(E)(iii));

D. The area must have a fully approved maintenance plan pursuant to section 175A of the Act (section 107(d)(3)(E)(iv)); and

E. The area has met all relevant requirements under section 110 and part D of the Act (section 107(d)(3)(E)(v)).

Section 175A of the Act sets forth the maintenance plan requirement for areas seeking redesignation from nonattainment to attainment. The plan must demonstrate continued attainment of the applicable NAAQS for at least ten years after the area is redesignated. Eight years after the redesignation, the state must submit a revised maintenance plan which demonstrates attainment for the ten years following the initial ten-year period. To provide for the possibility of future NAAQS violations, the maintenance plan must contain contingency measures adequate to assure prompt correction of the air quality problem.

III. Review of State Submittal

A. Maintenance Plan

1. Air Quality Data

The submittal contains an analysis of ozone air quality data which is relevant to the maintenance plan and to the redesignation request. (The redesignation request is discussed in Section III.C of this notice.) Ambient ozone monitoring data for 1989 through 1991 show attainment of the NAAQS in the Kansas City area, i.e., less than one expected exceedance per year. For a complete discussion of the NAAQS, the reader is referred to 40 CFR 50.9 and appendix H to that section. Although the 1991 data are not yet fully quality assured, EPA will review the quality of these data in conjunction with its final action of this SIP submittal. EPA will not take final action approving the redesignation unless it determines that attainment is based on three years of quality assured data.

Prior to the 1991 ozone season, the state had planned to base the redesignation request on the 1987 through 1989 air quality data; however, these data did not indicate attainment in strict accord with EPA's interpretation of the ozone standard. Although, under appendix H, attainment cannot be shown by the 1987 through 1989 data, the state's demonstration justifies the use of 1989 emissions levels as being representative of attainment.

2. Emissions Inventory

MDNR submitted comprehensive inventories of actual VOC emissions from point, area, and mobile sources. Because 1989 emission data were not consistently available for all VOC sources in the KCMA, 1988 was selected as the base year and was used to project emissions to 1989 and future years. The 1989 VOC inventory is considered most representative of attainment conditions because: (1) No ozone exceedances occurred in 1989; and (2) EPA's Phase I gasoline volatility controls (54 FR 11868) were implemented in 1989, resulting in significant VOC emission reductions.

Therefore, the attainment emission inventory for purposes of this SIP is based upon the 1989 emission values. All VOC emission estimates were reported in kilograms per typical summer day. The state submittal contains the detailed inventory data and summaries by county and source category.

The state demonstrated that point source VOC emissions were not artifically low due to local economic downturn. The state examined historical employment data for the Kansas City area for the years 1987 through 1989. No economic downturn was evident; employment in the manufacturing sector remained relatively stable during the period.

The state's inventory methodology was consistent with EPA guidance applicable at the time the plan was being developed (EPA-450/4-88-19, December 1988). Eighty percent rule effectiveness was applied for source categories subject to state regulations. Stationary sources with emissions greater than 10 tons per year were inventoried as point sources.

Mobile source emission estimates were generated using EPA's MOBILE4 model. For the 1988 base year (prior to EPA volatility restrictions), a 10.5 psi RVP gasoline volatility was used. In accordance with the EPA Phase I volatility restrictions, a 9.5 psi RVP gasoline volatility was input for 1989. For 1990 and 1991, a gasoline volatility of 9.0 psi RVP was used in accord with the KCMA's voluntary RVP reduction program (discussed further below). In accord with EPA's original June 11, 1990, Phase II volatility restrictions (56 FR 23658), a gasoline volatility of 7.8 psi RVP was assumed for 1992 and later years.

Due to the marginal, but persistent, history of ozone nonattainment in the KCMA, EPA and the states of Missouri and Kansas believed that an additional areawide VOC control measure was necessary to ensure that the ozone standard could be maintained with an adequate margin of safety. The states of Missouri and Kansas, the Mid-America Regional Council (MARC), and the Chamber of Commerce worked cooperatively to implement a voluntary program to control the volatility of gasoline supplied to the area for 1990 and 1991. Despite its voluntary nature, the program reduced gasoline volatility from 9.5 to 9.0 psi RVP from June 1 through September 1 in both 1990 and 1991. All petroleum refiners and pipeline companies agreed to participate. Also, the EPA Field Operations Support Division performed volatility tests of gasoline samples from the KCMA. The tests confirmed that the program achieved its goal. (As discussed in section III.A.3. below, additional reduction of gasoline volatility will be accomplished, beginning in 1992, as a result of EPA's Phase II volatility standards.)

The voluntary RVP control program resulted in a 8,189 kg/day areawide reduction in the projected 1990 VOC inventory. This equates to a 3.3 percent reduction from the 1989 attainment VOC inventory. Thus, the 8,189 kg/day VOC reduction serves as the attainment margin of safety. The states have committed to maintain future VOC emissions at or below the co-called ``action level'', i.e., VOC emissions will not be allowed to encroach upon the margin of safety. The action level concept is detailed in the above-mentioned EPA TSD.

3. Demonstration of Continued Attainment

a. State demonstration. The state's demonstration of continued attainment relies, in part, on EPA's Phase II gasoline volatility requirements. On June 11, 1990 (55 FR 23658), EPA promulgated state-by-state Phase II RVP gasoline standards in order to continue reductions in VOC emissions. Accordingly, under the Phase II program, a fuel volatility limit of 7.8 psi RVP was scheduled to become effective in 1992 and each year thereafter during the ozone season (May through September) in the state of Missouri.

However, the federal gasoline volatility requirements were modified by the 1990 CAAA, and EPA promulgated revised Phase II gasoline volatility requirements on December 12, 1991 (56 FR 65704). This latest rule revises the maximum allowable RVP from 7.8 to 9.0 psi in those areas which are currently designated as unclassifiable or in attainment with the NAAQS for ozone. However, as applicable to the KCMA, the RVP limit of 7.8 will go into effect as the area is presently designated nonattainment.

The Missouri portion of the KCMA was designated as nonattainment for ozone in the recently published part 81 Federal Register notice, November 6, 1991 (56 FR 56788). Therefore, continuation of the 7.8 psi RVP limit is federally enforceable in the KCMA, even after the area is redesignated to attainment, because of its nonattainment designation in the November 6, 1991 Federal Register notice. Also, the requirement for 7.8 psi RVP volatility is deemed necessary to ensure attainment and maintenance of the ozone standard as demonstrated by the mobile source emissions inventory projections (based on use of 7.8 psi RVP) in Missouri's ozone maintenance plan for the KCMA.

Areawide VOC emission were projected for the ten-year period following maintenance plan development. The projections show that the ozone standard will be maintained, i.e., VOC emissions are not expected to exceed the ``action level'' during this time period. Areawide VOC emissions are expected to decrease by over 20 percent during the next ten years.

The state's projection of VOC emissions is based on the Federal Motor Vehicle Control Program and EPA's Phase II volatility controls. The projections were developed prior to passage of the 1990 CAAA Amendments; thus, the federal on-board vapor recovery requirement and the new federal tailpipe standards were not considered.

b. Additional EPA Analysis. At the time Missouri and Kansas developed their maintenance plans, the current version of EPA's mobile source emissions model was MOBILE4.0. Since that time, MOBILE4.1 has become available. MOBILE4.1 was run to determine that effect, if any, the new model would have on the demonstration of continued attainment of the ozone standard. For any given year, MOBILE4.1 predicted lower VOC emissions than MOBILE4.0; however, the relative year-to-year trends were essentially identical. Thus, the new effect of MOBILE4.1 on the demonstration of continued attainment was not significant.

Using MOBILE4.1, the KCMA attainment level of VOC emissions changed from 245,060 kg/day to 227,007 kg/day. For this analysis, EPA determined the action level of VOC emissions to be 218,009 kg/day. Using MOBILE4.1 for projecting the mobile source component of the emissions inventory, the total KCMA VOC emissions in the year 2000 are projected to be 183,601 kg/day, which is 16 percent below the action level. Given this substantial margin (34,408 kg/day), EPA believes that VOC emissions will remain below the action level through the year 2002. (ten years after the redesignation becomes effective).

EPA also performed an analysis of projected NOx emissions for the KCMA. Given that VOC emissions will remain below the action level (as discussed above in section III.A.2.) for the next ten years, EPA wished to determine what increases to NOx emissions, if any, could be anticipated. Even with no growth in VOC emissions, an increase in NOx emissions (and the associated changes in atmospheric chemistry) could result in violations of the ozone standard in the KCMA. EPA's analysis showed no increase in KCMA NOx emissions through the year 2005. Therefore, with VOC emissions at, or below, the action level, and with NOx emissions not increasing, violations of the ozone standard are not anticipated. Pursuant to section 175A(a) of the Act, EPA finds that the maintenance plan demonstrates continued attainment of the ozone standard for the ten-year period following the effective date of the redesignation.

4. Annual Tracking and Inventory Updates

Continued attainment of the ozone NAAQS in the KCMA depends, in part, on the state's efforts toward tracking VOC emissions. The state has committed to completing comprehensive VOC point source inventory updates at least twice in each five-year period following the effective date of the area's redesignation. For years in which no comprehensive update is performed, the state will update the inventory using source permit and shutdown data.

Area and mobile source inventories will be updated at least once every five years to take advantage of new data and estimation procedures, e.g., U.S. Census data, revised EPA mobile source emission models, etc. For years in which no comprehensive area and mobile source inventories are developed, the state will estimate emissions using the most recently available projections from existing area and mobile source inventories

The state will submit annual progress reports to EPA which will summarize available VOC emissions data. Thus, on an annual basis, EPA and the state can ascertain whether actual VOC emissions are within the attainment inventory.

5. Contingency Plan

The level of VOC emissions in the KCMA will largely determine its ability to stay in compliance with the ozone NAAQS in the future. Although further reductions of VOC emissions are projected to occur during the next ten years, the state has provided contingency measures to be implemented in the event of a future ozone air quality problem.

Two potential scenarios could result in the implementation of contingency measures. The first scenario would be an increase in VOC emissions which exceeds the ``action line'' level (encroaching into the emission margin of safety), but does not result in ozone violations. The second situation, regardless of the actual VOC emissions, would be violations of the NAAQS. As mentioned above, the state will provide annual progress reports which will evaluate the integrity of VOC emissions safety margin. Section 5.3 of the state submittal gives the details of the contingency provisions under both scenarios. Contingency measures include: (1) VOC emission offsets for new and modified stationary sources; (2) transportation control measures; (3) Stage II vapor recovery; (4) a vehicle I/M program; (5) VOC controls on minor new sources; and (6) RACT for sources covered by new EPA Control Technique Guideline (CTG) documents. Contingency controls would require the state's legislative and/or administrative approval before they could be implemented. The contingency measures provided in the state submittal meet the requirements of section 175A(d) of the Act.

6. Commitment to Submit Subsequent Maintenance Plan Revisions

In accord with section 175A of the Act, the state has committed to submit a revised maintenance SIP eight years after the area is redesignated to attainment.

B. Additional Reasonably Available Control Technology (RACT) Regulations

In accord with section 172(b)(2) of the 1977 Act, the KCMA was required to have SIP rules representing RACT for all VOC source categories covered by Group I, II, and III CTG documents. RACT rules were also required for all major non-CTG sources.

At the time EPA approved the SIP control strategy (54 FR 10322 and 54 FR 46232), EPA and the state believed that all the RACM requirements had been met; rules were in place for all applicable CTG and non-CTG source categories. Moreover, the rules had been revised for consistency with EPA's ``Blue Book.'' However, during the maintenance plan development process, EPA learned that the state needed an additional RACT regulation to address an unregulated non-CTG major source categoryÄlithographic printing. The state also made corrections to its cutback asphalt and definitions rules. These rule actions are discussed below. All of the state's existing and new VOC RACT rules will remain in effect after the KCMA is redesignated to attainment for the ozone NAAQS.

10 CSR 10-2.340 Control of Emissions from Lithographic Printing Facilities

This non-CTG RACT rule applies to nine existing facilities and new facilities that have the potential to emit more than 100 TPY of VOC from lithographic printing operations. VOCs from heat-set inks and the associated dryers are required to be reduced by 90 to 93 percent over pre-RACT levels through the installation of add-on control equipment. Evaporative emissions from cleanup solvents will be reduced by 49 percent, with VOCs from fountain solutions decreasing by 8 percent. VOC emission reductions from fountain solutions are not as large as had been anticipated because many of the subject facilities have already reduced the use of alcohol additives, or have converted to low-VOC alcohol substitutes. The rule was adopted by the Missouri Air Conservation Commission (MACC) after proper notice and public hearing and will become effective ten days after its date of publication in the Code of State Regulations (CSR).

Appendix G of the state submittal contains a demonstration that the rule constitutes RACT. In its RACT determination, the state generally relied upon research conducted by other states that have proposed or adopted similar rules, feedback from local lithographic printers, information provided by printing trade associations and trade publications, and research conducted for EPA's pending publication of a CTG document for lithographic printing (scheduled for release sometime in 1992-93).

10 CSR 10-2.220 Liquefied Cutback Asphalt Paving Restricted

This rule, as amended, now applies during the months of April through October. Previously, the applicable season had been May through September. The rule now includes recordkeeping requirements on the production, sales, and use of cutback asphalt. Such records must be maintained for at least two years and must be made available to the state upon request. The rule amendment was adopted by the MACC after proper notice and public hearing and will become effective ten days after its date of publication in the CSR.

10 CSR 10-6.020 Definitions

In this rule, the state expanded its definition of ``person'' so it would better apply to the gasoline marketing industry. The term ``person'' now applies to any legal successor, employees, or agents of the entities previously included in the definition. The definitions of ``Reid Vapor Pressure'' and ``gasoline'' were updated, and a definition of ``retail outlet'' was added. The amendments to the definitions rule were adopted by the MACC after proper notice and public hearing and will become effective ten days after being published in the CSR.

EPA believes that these three rules (as discussed above) constitute RACT for all affected sources. Therefore, EPA proposes approval of these rules.

C. Redesignation Request

The Missouri redesignation request for the KCMA meets the five requirements of section 107(d)(3)(E). Following is a brief description of how the state has fulfilled each of these requirements. EPA's TSD contains a more in-depth analysis of the submittal with respect to certain of these criteria.

1. Attainment of the Ozone NAAQS

The KCMA has provisionally met the first statutory criterion of attainment of the ozone NAAQS. EPA's analysis of the ozone air quality data is discussed above in Section III.A.1. EPA will not take final action approving the redesignation unless it determines that attainment is based on three years of quality assured data.

2. Reductions are Permanent and Enforceable

EPA approved the Missouri SIP control strategy for the KCMA satisfied that the rules, and therefore the emission reductions achieved as a result of those rules, were enforceable. Since that time, the Agency has remained satisfied with those rules and has not issued a SIP call pursuant to section 110(a)(2)(H), finding them to be inadequate. The emissions inventory, discussed in section III.A.2. above, is based on reductions achieved through control measures in the SIP; therefore, EPA finds that the emission reductions are permanent and enforceable.

3. A Fully Approved Maintenance Plan

In today's notice, EPA is proposing approval of the state's maintenance plan for the KCMA. As discussed above in Section III.A., EPA finds that the Missouri submittal meets the requirements of section 175A. If EPA determines after notice and comment that it should give final approval to the maintenance plan, the KCMA will have a fully approved maintenance plan in accordance with section 175A. EPA will not redesignate the area to attainment before it gives final approval to the maintenance plan.

4. Fully Approved SIP Meeting the Requirements of section 110 and Part D

a. Section 110 Requirements. In 1980 and 1989, EPA fully approved the state's SIP for the KCMA as meeting the requirements of section 110(a)(2) of the 1977 Act (45 FR 24140, 45 FR 85005, 54 FR 10322, and 54 FR 46232). The amended Act, however, modifies several of these requirements. Moreover, the amended Act requires that for redesignation a nonattainment area must have a fully approved SIP under section 110(k)Äa new provision. EPA addresses the modified portions of section 110(a)(2) below. As discussed in Section III.B above, the state has submitted two new rules for SIP approval. By today's action, EPA proposes approval of these two rules, and the maintenance plan. Contingent upon final approval of the SIP, EPA proposes approval of the Missouri SIP for the KCMA under section 110(k) of the amended Act. EPA will not take final action redesignating the KCMA to attainment until it has issued a final approval of the entire SIP for the KCMA.

Although section 110 was amended by the CAAA, the KCMA SIP meets the requirements of amended section 110(a)(2). A number of the requirements did not change in substanceÄsection 110(a)(2)(B); (C); (E) (i) and (ii); (F); (G); (H); (J); (L) and (M)Äand, therefore, EPA has determined that the presence of a fully approved SIP indicates that these requirements have been met.

A few of the other requirements deserve a more detailed analysis. First, the section 110(a)(2) requirement that all elements of the SIP are enforceable, is essentially the same as the section 172(c)(6) requirement. As discussed below in relation to the section 172(c)(6) requirement, we have found that the existing SIP contains the necessary enforceable measures. Section, as to section 110(a)(2)(D), which also remains essentially unchanged, it is important to note that the state has provisions adequate to ensure that it is not contributing to nonattainment problems across the state border. These provisions are found in the existing SIP. Third, section 110(a)(2)(E)(iii) establishes a new requirement that the state retain the responsibility for ensuring adequate implementation of the SIP elements. Since the state adopted and submitted the rules, it has retained direct responsibility for ensuring adequate implementation. Fourth, new section 110(a)(2)(I) reinforces the requirement that the state comply with all Part D requirements (discussed further below). Finally, section 110(a)(2)(K) reinforces EPA's authority to require states to do air quality modeling to support SIP demonstrations. Since EPA is approving the demonstration of continued attainment in the maintenance plan, Missouri has met this requirement for purposes of redesignating the Missouri portion of the Kansas City ozone nonattainment area to attainment.

b. Part D Requirements. Before the KCMA may be redesignated to attainment, it also must have fulfilled the applicable requirements of Part D. Under Part D, an area's classification indicates the requirements to which it will be subject. Subpart 1 of Part D sets forth requirements applicable to all nonattainment areas regardless of classification. Subpart 2 of Part D establishes requirements for areas classified as marginal or above. For ozone nonattainment areas, classification is based on the design value of the area. Areas that violated the ozone standard during the three-year period (1987 through 1989), but had a design value of less than 0.121 ppm, fell below the classification cutpoint of section 181 and were, therefore, deemed ``submarginal'' as of the date of enactment of the 1990 Amendments to the Act. On November 6, 1991, the KCMA was classified as submarginal (56 FR 56694). Therefore, in order to be redesignated, the state need only meet the requirements of subpart 1 of Part D. Specifically, the state must meet the requirements set forth in section 172(c) and section 176.

1. Section 172(c) Plan Provisions

Since EPA did not issue a SIP call after the state's 1988 approved submittal, the section 172(c)(1) RACM requirement (which is the same as the requirement is preamended section 17(b)(2) and (3)) was met by EPA's approval of the SIP under the preamended Act. The state has actually attained the standard based on the three years of data from 1989 through 1991. Section 172(c)(1) requires the state to adopt and implement RACM as expeditiously as practicable and to provide for the attainment of the NAAQS. At the time EPA approved the KCMA plan, the Agency determined that it was consistent with RACT and RACM requirements of the Act. As discussed previously herein, EPA later determined that additional RACT rules were needed in the KCMA. The additional RACT rules, included in the state submittal, fulfill the RACT and RACM requirements of the Act.

The RACM requirement also provides that the SIP must provide for attainment. EPA never acted on Missouri's attainment demonstration for the KCMA. Under the amended Clean Air Act, the attainment demonstration requirement no longer applies to ozone nonattainment areas that are classified as marginal (section 182(a)(4)). For marginal areas, this specific provision overrides the general attainment demonstration requirement of section 172(c)(1) that is applicable to all ozone nonattainment areas. On November 6, 1991, the KCMA was designated as a submarginal ozone nonattainment area (56 FR 56694). Since submarginal areas, such as Kansas City, have an even less severe ozone problem than marginal areas, EPA is interpreting the section 172(c)(1) attainment demonstration requirement not to apply to submarginal areas. Therefore, it is not necessary for EPA to take final action on the existing attainment demonstration for purposes of redesignating the Missouri portion of the Kansas City ozone nonattainment area.

Several section 172(c) requirements lose their continued force once an area has demonstrated attainment and maintenance of the NAAQS. The requirement for reasonable further progress (RFP) only has relevance during the time it takes an area to attain the NAAQSÄeach year the area must make RFP toward attainment. EPA originally approved the KCMA RFP demonstration under preamended section 172(c)(2) for the period preceding the statutorily approved attainment date. The preamended section 172(b)(3) requirement is essentially the same as the new section 172(c)(2) RFP requirement. Since the KCMA has attained the NAAQS, its SIP has already achieved RFP toward that goal. In addition, because the KCMA has attained the NAAQS and is no longer subject to an RFP requirement, the section 172(c) contingency measures are not applicable. Such contingency measures must take effect if the area fails to meet an RFP milestone or fails to attain the NAAQS; the KCMA no longer has RFP milestones and has already attained the standard. The area, however, is still subject to the section 175A contingency measures.

Similarly, once an area is redesignated to attainment, nonattainment new source review (NSR) requirements are not applicable. The area is then subject to prevention of significant deterioration (PSD) requirements instead of the NSR program. EPA does not believe it appropriate to require the state to adopt a revised NSR program (meeting the requirements of the amended Act) just to qualify for redesignation, since that program will be replaced by the existing Missouri PSD program upon redesignation and any corresponding amendments to the state rules.

As discussed in Section III.A.2. above, the state submittal includes an emissions inventory. The maintenance plan emissions inventory fulfills the section 172(c) requirement.

2. Conformity

Section 176 of the Act requires states to develop transportation/air quality conformity procedures which are consistent with federal conformity regulations and to submit these procedures as a SIP revision by November 15, 1992. EPA has not promulgated final conformity regulations; however, the state has committed to develop conformity procedures consistent with the final federal regulations and will submit an appropriate SIP revision. Pages 95 and 96 of the state submittal discuss the general principles to which the state will adhere in developing conformity procedures for the Kansas City area.

On June 7, 1991, EPA and the Department of Transportation issued Interim Conformity Guidance for completing conformity determinations until the final conformity regulations are promulgated. MARC (the metropolitan planning organization for the Kansas City area) completed a conformity determination for Kansas City regional transportation plans and programs under the Interim Guidance, which the state has reviewed and approved. The conformity determination is included as appendix L to the state submittal.

EPA believes that the section 176 conformity requirement is sufficiently met because the promulgation date for conformity procedures has not passed and the state has committed to adopt appropriate procedures.

IV. Conclusion

EPA is soliciting public comments on this notice and on issues relevant to EPA's proposed action. Comments will be considered before taking final action. Interested parties may participate in the federal rulemaking procedure by submitting written comments to the address above.

Proposed Action

In today's notice, EPA proposes to approve the Kansas City ozone maintenance plan, and the RACT rule submittals, because it meets the requirements of section 175A. In addition, the Agency is proposing approval of the redesignation request for the Kansas City area, subject to final approval of the maintenance plan, because the state has demonstrated compliance with the requirements of section 107(d)(3)(E) for redesignation. Nothing in this action should be construed as permitting or allowing or establishing a precedent for any future request for revision to any SIP. Each request for revision to the SIP shall be considered separately in light of specific technical, economic, and environmental factors and in relation to relevant statutory and regulatory requirements.

Under 5 U.S.C. 605(b), EPA certifies that this SIP revision and redesignation will not have a significant economic impact on a substantial number of small entities (see 46 FR 8709).

The Office of Management and Budget has exempted this rule from the requirements of section 3 of Executive Order 12291.

List of Subjects in 40 CFR Part 52

Air pollution control, Hydrocarbons, Intergovernmental relations, and Ozone.

List of Subjects in 40 CFR Part 81

Air pollution control, National parks, and Wilderness areas.

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

Dated: January 3, 1992.

Morris Kay, Regional Administrator.

[FR Doc. 92-1068 Filed 1-14-92; 8:45 am]