EPA proposed to defer for three years the application of the PSD and Title V permitting requirements for biogenic carbon dioxide emissions from bioenergy and other biogenic stationary sources.

EPA proposed to amend certain NESHAP regulations for the Maricopa County air quality department in Arizona and the Santa Barbara County air pollution control district in California; see above for direct final rule.

EPA proposed amendments to the NESHAPs for mercury emissions from mercury cell chlor-alkali plants.

EPA proposed final amendments to the NESHAPs for existing stationary spark ignition reciprocating internal combustion engines; see above for direct final rule.

EPA issued a final rule requiring monitoring and reporting of greenhouse gas (GHG) emissions from additional sources of fluorinated GHGs.

EPA extended and clarified its stay of the final rule entitled "Prevention of Significant Deterioration (PSD) and Nonattainment New Source Review (NSR): Reconsideration of Inclusion of Fugitive Emissions."

The Agricultural Marketing Service proposed revisions to the Federal Seed Act to update regulations and to prevent potential conflicts with states.

EPA determined that hydrofluoroolefin-1234yf is an acceptable substitute for chlorofluorocarbon-12, an ozone-depleting substance, in motor vehicle air conditioning for new passenger cars and light-duty trucks.

EPA finalized revisions to its Protocol Gas Verification Program and the minimum competency requirements for air emissions testing.

EPA approved the Gila River Indian Community's tribal implementation plan to regulate air quality within the exterior boundaries of the tribe's reservation.