The Environmental Protection Agency on Jan. 23 issued a proposed rule that responds to state implementation plan submissions from Arizona, New Mexico, and Tennessee for the 2015 eight-hour ozone National Ambient Air Quality Standards.
The proposed rule is titled “Supplemental Air Plan Actions: Interstate Transport of Air Pollution for the 2015 8-hour Ozone National Ambient Air Quality Standards and Supplemental Federal “Good Neighbor Plan” Requirements for the 2015 8-hour Ozone National Ambient Air Quality Standards.”
The proposal would partially approve/partially disapprove state implementation plan submissions from Arizona, New Mexico, and Tennessee for the 2015 eight-hour ozone NAAQS.
EPA is also proposing a federal implementation Plan requirement to address Arizona, Iowa, Kanas, New Mexico, and Tennessee’s contribution to nonattainment and maintenance of the 2015 ozone NAAQS.
The FIP would establish a nitrogen oxide emissions trading program for power plants in the five states to allow for an allowance-based ozone season (May 1- September 30) trading program. The trading program would begin in 2025.
The proposal would also establish NOx limits for certain industrial sources in Arizona beginning in 2027. The FIP would extend to Indian country within the upwind states covered by the proposed action, including Indian reservation lands.
Electric generating units in Arizona, Iowa, Kansas, New Mexico, and Tennessee would participate in the revised Cross-State Air Pollution (CSAPR) NOx ozone season group 3 trading program established in the March 2023 final federal Good Neighbor Plan for the 2015 Ozone NAAQS (Final GNP Rule).
Iowa, Kansas, and Tennessee are currently covered under the CSAPR NOX ozone season group 2 trading program.
EPA is amending the existing FIPs to transition EGUs in Group 2 states to the revised Group 3 trading program at the beginning of the 2025 ozone season.
Arizona and New Mexico will be issued new FIPs as they are not currently covered under the CSAPR NOx ozone season trading program.
EPA is proposing to keep the Group 3 trading program design elements that were finalized in the final GNP Rule.
EGUs over 25 megawatts of capacity are covered by the FIPs and are subject to state emission budgets.
EPA has determined that the timeframe for optimizing existing SCR and SNCR controls is about two months or less, and the timeframe for upgrading combustion controls is about six months.
Additionally, EPA proposes that the first ozone season for installing new selective non-catalytic reduction technology (SNCR) should be aligned with the first ozone season feasible for the installation of selective catalytic reduction technology (SCR), i.e., the 2027 ozone season.
As in the Final GNP Rule, EPA proposes that SCR installation at EGUs can occur over a 36–48-month period. In Arizona, the phase-in of SCRs would occur over the 2027 and 2028 ozone seasons.
The proposed preset state ozone season NOx emissions budgets for covered EGUs in Arizona, Iowa, Kansas, New Mexico, and Tennessee for the control periods in 2025 through 2029 are detailed in the proposal.
Starting with the 2025 the state emissions budgets for Arizona, Iowa, Kansas, New Mexico, and Tennessee would reflect emissions reductions achievable through optimization of installed controls and installation of new state-of-the-art combustion controls.
In addition, for Arizona but not for the other four states, the emissions reductions achievable through the installation and operation of new SCR controls would be phased in starting with the preset and dynamic budgets for the 2027 control periods and would be fully reflected in the preset and dynamic budgets for 2028 and later control periods.
A pre-publication version of the proposal, a summary fact sheet and supporting documents are available here; https://www.epa.gov/Cross-State-Air-Pollution/good-neighbor-plan-2015-ozone-naaqs
Once the proposal is published in the Federal Register there will be a 30-day public comment period.