California's Desert Air Permits Get EPA Overhaul Approval
Published Date: 3/23/2026
Rule
Summary
The EPA is giving a thumbs-up to updated air pollution rules for the Mojave Desert area in California, making it easier to manage permits for new or changed pollution sources. These changes kick in on April 22, 2026, and mainly affect businesses needing permits to keep the air clean. This update helps balance protecting the environment while supporting local growth without extra costs.
Analyzed Economic Effects
5 provisions identified: 4 benefits, 0 costs, 1 mixed.
Mojave Desert NSR Rules Conditionally Approved
If you own or operate a facility that needs New Source Review (NSR) permits in the Mojave Desert Air Quality Management District, the EPA is conditionally approving District Rules 1301, 1302 (except subsections C(5) and C(7)(c)), 1303, 1304, and 1305 into the California SIP. These rules (as amended March 25, 2024) become part of the federal plan on April 22, 2026 and govern permitting for new and modified sources under the nonattainment NSR program.
One-Year Fix Required for Rule 1304
The EPA's approval is conditional on the Mojave Desert Air Quality Management District (MDAQMD) and the California Air Resources Board (CARB) revising Rule 1304 to correct a remaining deficiency and submitting that revision within 12 months of the rule's effective date. The effective date is April 22, 2026, so the required submission must occur within one year (by April 22, 2027); if the District or CARB fail to meet this commitment, the conditional approval is treated as a disapproval.
Offset and Highway Sanctions Stayed
The EPA previously issued an Interim Final Determination (published July 24, 2025) to stay the imposition of the offset sanction and to defer the highway sanction that were triggered by the June 30, 2023 limited disapproval. The conditional approval finalized April 22, 2026 stays those sanctions unless the conditional approval converts to disapproval.
No CO2 Requirement in NSR Permits
The EPA said that the minor and nonattainment NSR regulations do not require states to regulate carbon dioxide (CO2), so permit applicants in the MDAQMD are not required by this action to include CO2 emission estimates or social cost of carbon calculations in their NSR permit evaluations. The EPA referenced its longstanding position that NSR programs do not apply to CO2 for these permitting programs.
EPA: No Significant Small-Business Impact
Under the Regulatory Flexibility Act, the EPA certified that this final action will not have a significant economic impact on a substantial number of small entities because it does not impose requirements beyond those in state law. This means the EPA does not expect new nationwide small-business burdens from this approval.
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