Conditional Approval; Contingency Measure State Implementation Plan for the 2008 Ozone Standard; San Joaquin Valley, California

Issuing agencies

Abstract

The Environmental Protection Agency (EPA) is proposing to conditionally approve a state implementation plan (SIP) submission under the Clean Air Act (CAA or "Act") that addresses the contingency measure requirements for the 2008 ozone national ambient air quality standards (NAAQS or "standards") for the San Joaquin Valley ozone nonattainment area. The SIP submission, titled the "Ozone Contingency Measure State Implementation Plan Revision for the 2008 and 2015 8-hour Ozone Standards" ("2024 SJV Ozone Contingency Measure Plan," "Contingency Measure Plan," or "Plan") relies on two ozone contingency measures that the EPA has already approved in separate rulemakings. The proposed approval is conditional because it also relies on commitments by the State air agency and regional air district to supplement the 2024 SJV Ozone Contingency Measure Plan with submission of specific additional contingency measures within one year of the EPA's final conditional approval. The EPA is proposing conditional approval of the SIP submission because the Agency has preliminarily determined that the existing approved contingency measures, the commitments to submit additional contingency measures, and the justification for not adopting contingency measures that would achieve the recommended amount for such measures, meet the applicable requirements for such SIP submissions under the CAA and the EPA's implementation regulations for the San Joaquin Valley for the 2008 ozone NAAQS. The proposed conditional approval, if finalized, would add the 2024 SJV Ozone Contingency Measure Plan to the federally enforceable California SIP.