EPA Approves Clearer Pollution Definitions for Mojave Desert Air Managers
Published Date: 1/8/2026
Rule
Summary
The EPA just gave a thumbs-up to updated air pollution rules for California’s Mojave Desert area, making sure the definitions used to fight pollution are clear and up-to-date. This change affects local air quality managers and businesses, helping everyone follow the rules better starting February 9, 2026. Old, outdated rules are being tossed out, so the air stays cleaner without confusion or extra costs.
Analyzed Economic Effects
3 provisions identified: 3 benefits, 0 costs, 0 mixed.
Mojave Desert Definitions Approved
The EPA approved Mojave Desert Air Quality Management District (MDAQMD) Rule 102, “Definition of Terms,” as part of the California State Implementation Plan (SIP). The September 28, 2020 version of Rule 102 will take effect February 9, 2026 and replaces the previously approved version in the SIP.
Older County Definitions Rescinded
The EPA rescinded earlier definition rules from the SIP for the San Bernardino County Air Pollution Control District and the Riverside County Air Pollution Control District that were previously approved on December 21, 1978. Those older Rule 102 entries are deleted from the SIP and replaced by the MDAQMD Rule 102 entry effective February 9, 2026.
No New Federal Costs For Small Entities
The EPA says this SIP approval only adopts state law into the federal SIP and does not impose additional federal requirements. The rule is certified as not having a significant economic impact on a substantial number of small entities.
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