The EPA said it was following Clean Air Act requirements and meeting a court deadline in proposing the rules, which is said would help states “fully resolve” their Clean Air Act “good neighbor” obligations for the 2015 Ozone National Ambient Air Quality Standards (NAAQS).

Beginning in 2023, EPA is proposing to include electric generating units in 25 states in the Cross-State Air Pollution Rule (CSAPR) NOX Ozone Season Group 3 Trading Program, which would be revised and strengthened for the 2015 ozone NAAQS. 

The states include Alabama, Arkansas, California, Delaware, Illinois, Indiana, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Missouri, Nevada, New Jersey, New York, Ohio, Oklahoma, Pennsylvania, Tennessee, Texas, Utah, Virginia, West Virginia, Wisconsin, and Wyoming.

Beginning in 2026, EPA is proposing emissions standards for certain industrial sources in 23 states that EPA said have a “significant impact” on downwind air quality. EPA said its proposed limits on emissions from power plants and industrial sources reflect the installation and operation of “proven, cost-effective emission controls,” which it said in many cases have been implemented for years in numerous states.

The 23 states are Alabama, Arkansas, California, Illinois, Indiana, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Missouri, Nevada, New Jersey, New York, Ohio, Oklahoma, Tennessee, Texas, Utah, West Virginia, Wisconsin, and Wyoming.

EPA projects that the proposed rule by 2026 would prevent around 1,000 premature deaths and avoid more than 2,000 hospital and emergency room visits, 1.3 million cases of asthma symptoms, and 470,000 school absence days. It said reducing ozone levels also would improve visibility in national and state parks and increase protection for sensitive ecosystems, coastal waters, estuaries, and forests.

In 2026, the cost of achieving these reductions would be roughly $1.1 billion (in 2016 dollars), EPA said, and offer at least $9.3 billion in benefits. 

EPA said its proposed limits on NOX pollution from power plants would build upon existing CSAPR trading programs by including additional features that promote the consistent operation of emission controls to enhance public health and environmental protection for the region and for local communities.

Features would include daily emissions rate limits on large coal-fired units to promote more consistent operation and optimization of emissions controls, limits on “banking” of allowances, and annual updates to the emission budgets starting in 2025 to account for changes in the generating fleet.

EPA also proposed emissions standards for new and existing emissions units in additional industries: reciprocating internal combustion engines in pipeline transportation of natural gas; kilns in cement and cement product manufacturing; boilers and furnaces in iron and steel mills and ferroalloy manufacturing; furnaces in glass and glass product manufacturing; and high-emitting, large boilers in basic chemical manufacturing, petroleum and coal products manufacturing, and pulp, paper, and paperboard mills.

EPA said its proposal implements the Clean Air Act’s “good neighbor” or “interstate transport” provision, which requires each state to submit a State Implementation Plan (SIP) that ensures sources within the state do not contribute significantly to nonattainment or interfere with maintenance of the NAAQS in other states. Each state must make this new SIP submission within three years after the promulgation of a new or revised NAAQS.

Where EPA finds that a state has not submitted a good neighbor SIP, or if the EPA disapproves the SIP, the EPA must issue a Federal Implementation Plan (FIP) within two years to assure downwind states are protected. EPA said it is reviewing and acting on SIP submissions from the relevant states covered by this proposal.

EPA said it will take comment on the proposed rule for 60 days after it is published in the Federal Register.