Proposed rule · 2026-13845

Approval and Promulgation of Implementation Plans; California; San Joaquin Valley; Revisions to Motor Vehicle Emissions Budgets for Ozone

The Environmental Protection Agency (EPA) is proposing to approve revisions to the State of California's State Implementation Plan (SIP) for the San Joaquin Valley (SJV) area. The revisions consist of an update to the SJV area's motor vehicle emissions budgets ("budgets") for nitrogen oxides (NO<INF>X</INF>) and volatile organic compounds (VOC) for the 2008 8-hour ozone national ambient air quality standard (NAAQS or "standard"). These updated budgets for 2026, 2029, and 2031 were developed with the latest modeling method approved for California. These updated budgets apply to all subareas within SJV. If the EPA approves these budgets, they would supersede the existing approved SJV subarea budgets for the 2008 ozone NAAQS that were based on an earlier emissions model. The EPA is proposing to approve the updated SJV ozone budgets in accordance with the requirements of the Clean Air Act (CAA or "Act") and the EPA's regulations.