Approval and Promulgation of Implementation Plans; Illinois
air-emissions · Rule · Published 1996-02-12 · Effective 1996-03-13 · IL · 61 FR 5291
Document
Document number
96-2966
Federal Register citation
61 FR 5291
CFR reference
40 CFR 52
Type
Rule
Action
Final rule.
Category
air-emissions
Publication date
1996-02-12
Effective date
1996-03-13
State
IL
EPA docket
IL132-2-7237
Abstract
The United States Environmental Protection Agency (USEPA) is approving Illinois' request to exempt the Chicago ozone nonattainment area from the applicable oxides of nitrogen (NO<INF>X) transportation conformity requirements. The Chicago ozone nonattainment area is classified as severe nonattainment for ozone. The request is based on the urban airshed modeling (UAM) conducted by the Lake Michigan Ozone Control Program (LMOP) which shows that additional NO<INF>X reductions in the Chicago area will not contribute to attainment of the ozone standard. Approval of this NO<INF>X exemption for transportation conformity will simplify the process of demonstrating that transportation plans and projects will not contribute to violations of the ozone standard. Comments received on the August 16, 1995, proposal are addressed in this rulemaking. The continued approval of this exemption is contingent on the results of subsequent modeling including the final ozone attainment demonstration and plan for the Chicago nonattainment area. This plan is expected to be submitted by mid-1997 and to incorporate the results of the Ozone Transport Assessment Group (OTAG) process. The attainment plan will supersede the initial modeling results as the basis for the waiver which USEPA is granting in this notice. If the attainment plan relies on NO<INF>X controls on mobile sources in the Chicago ozone nonattainment area to demonstrate attainment, the NO<INF>X waiver for transportation conformity will be reconsidered. To the extent the final plans achieve attainment of the ozone standard without additional NO<INF>X reductions from mobile sources, the NO<INF>X exemption would continue. USEPA's rulemaking action to reconsider the initial NO<INF>X waiver may occur simultaneously with rulemaking action on the attainment plans. This NO<INF>X waiver approval does not change the transportation conformity requirement for a NO<INF>X budget test unless the attainment SIP shows that NO<INF>X emissions could gr