The Environmental Protection Agency (EPA) is proposing to approve a revision to the Mojave Desert Air Quality Management District (MDAQMD or ``District'') portion of the California State Implementation Plan (SIP). This revision concerns emissions of oxides of nitrogen (NO<INF>X</INF>) from Portland cement kilns. We are proposing to approve a local rule to regulate these emission sources under the Clean Air Act (CAA or the Act). We are taking comments on this proposal and plan to follow with a final action.

The Environmental Protection Agency (EPA) is approving revisions to the Oregon state implementation plan (SIP) submitted by the State of Oregon (Oregon) on December 9, 2020 and December 22, 2021. The revisions update the SIP-approved vehicle inspection program for the Portland and Medford areas. The EPA is approving the SIP submittal as consistent with Clean Air Act (Act or CAA) requirements.

The Environmental Protection Agency (EPA) is approving a state implementation plan (SIP) revision submitted by the State of Delaware. The revision pertains to the reduction of the maximum allowable sulfur content limit for distillate fuels, from a current limit of 3000 parts per million (ppm) (0.3% by weight) to 15 ppm (0.0015% by weight) and residential fuels from a current limit of 1.0% by weight to 0.5% by weight. This revision also adds requirements for sampling and testing along with certification and recordkeeping.

The Environmental Protection Agency (EPA) is taking final action to approve a State Implementation Plan (SIP) revision submitted by the State of Alabama, through the Alabama Department of Environmental Management (ADEM), in a letter dated October 18, 2021. The revision includes corrections to deficiencies to Alabama's regulation titled ``NO<INF>X</INF> Budget Program Monitoring and Reporting'' (AL NO<INF>X</INF> SIP Call Monitoring Rule), which EPA previously conditionally approved into the SIP.