EPA Region 9 proposed to reissue a general NPDES permit for water discharges from facilities classified as low threat located in the Navajo Nation.

SIP Approval: California (revisions concerning provisions for Clean Fuels for Fleets for the 2015 ozone NAAQS in the Riverside County, Sacramento Metro, San Joaquin Valley, Los Angeles–South Coast Air Basin, Ventura County, and Los Angeles–San Bernardino Counties nonattainment areas).

United States v. BP Products North America, No. 2:23-cv-166 (N.D. Ind. May 17, 2023). A settling CAA defendant must perform injunctive relief, including the installation of a permanent benzene stripper; spend $5 million to implement a supplemental environmental project intended to reduce diesel emissions in the surrounding communities; and pay a total financial penalty of $40 million, comprised of a $31,424,000 civil penalty and $8,576,000 in stipulated penalties for violations of an earlier consent decree, in connection with alleged violations of NESHAPs for benzene waste operations and new source performance standards for volatile organic compound emissions from refinery wastewater systems, as well as the general requirement to use good air pollution control practices at its refinery in Whiting, Indiana.

SIP Proposal: Alaska (revisions and repeal of state regulations to limit water vapor emissions that may contribute to ice fog and to address the use of high-sulfur marine fuels near the communities of St. Paul Island and Unalaska).

EPA proposed to list certain substitutes under the Significant New Alternatives Policy program in refrigeration and air conditioning.

EPA seeks comment on two sets of amendments to the California Air Resources Board's Small Off-Road Engine regulation.

NMFS announced its 90-day finding on a petition to list the smalltail shark as threatened or endangered under the ESA, finding that listing may be warranted and commencing a status review of the species.

EPA proposed revised new source performance standards for greenhouse gas (GHG) emissions from new fossil fuel-fired stationary combustion turbine electric generating units (EGUs) and for GHG emissions from fossil fuel-fired steam generating units that undertake a large modification; emission guidelines for GHG emissions from existing fossil fuel-fired steam generating EGUs, which include both coal-fired and oil/gas-fired steam generating EGUs; emission guidelines for GHG emissions from the largest, most frequently operated existing stationary combustion turbines, and is soliciting comment on approaches for emission guidelines for GHG emissions for the remainder of the existing combustion turbine category; and to repeal the Affordable Clean Energy Rule.

FWS designated approximately 1,869 acres in Miami-Dade County, Florida, as critical habitat for the Miami tiger beetle under the ESA.

SIP Proposal: Missouri (removal of provision that allows the burning of illegal and waste pharmaceutical drugs in crematories and animal incinerators).