Document e5MDr8eO0OMMm75Ldenr7mRbM

Presidential Exemption Request GVEA Healy Power Plant March 31, 2025 GVEA's service area and membership are exceptionally vulnerable to disruptions in power generation. GVEA maintains an expansive, practically islanded electrical grid, in an extreme subarctic environment, at an isolated location on the geographical fringe of civilization. GVEA has a strong record of electrical reliability, but the mounting challenges of fuel unavailability, rising costs, and burdensome environmental regulations have undermined GVEA's resilience. A disruption to any one of GVEA's electrical generating facilities can seriously compromise GVEA's ability to meet electrical demands throughout its service territory. GVEA is a vital electrical provider to the military installations in Interior Alaska, and to their regional support networks for personnel, equipment, and supplies, and accordingly, GVEA's reliability is absolutely in the national security interest of the United States. GVEA asks that you recognize this cooperative's essential need for relief from the infeasible emissions limits and unattainable compliance timeframes in MATS by granting a two-year Presidential Exemption from the applicable MATS rule compliance date. 2. Technical Infeasibility for the PM Standard The 2024 amendments to 40 CFR 63 Subpart UUUUU changed the filterable PM standard from 0.030 lb/MMBtu to 0.010 lb/MMBtu, effective on July 6, 2027. The 2024 amendments also changed the compliance demonstration method by removing the option to perform source tests and, instead, requires the use of a PM CEMS. The U.S. Environmental Protection Agency (EPA) amended the testing requirements in 40 CFR 63 Subpart UUUUU to increase the required PM sampling volume collected during each reference method test run for the PM GEMS correlation validation from 1 dry standard cubic meter (dscm) to 4 dscm. GVEA has previously submitted comments addressing the amendments. Those comments are provided in Attachments 1 and 2. Based on GVEA's experience with PM CEMS, installing a PM GEMS on an EGU and meeting compliance with the GEMS data collection requirements in 40 CFR 63 Subpart UUUUU is not technically feasible without incurring numerous deviations from the applicable regulations. Per 40 CFR 63.10020(d): . . . Failure to collect required quality-assured data during monitoring system malfunctions, monitoring system out-of-control periods, or repairs associated with monitoring system malfunctions or monitoring system out-of-control periods is a deviation from the monitoring requirements." PM CEMS are typically light scattering devices. These CEMs do not directly measure filterable PM. The electrical output from the device is compared to empirical results from filterable PM source tests, and a correlation between the PM CEMS output and the source tests is developed in accordance with EPA Performance Specification 11 (PS-11). The correlation can then be used to Page 4 of 8 Sierra Club FOIA 2025-EPA-04883 ED_018388_00000057-00004 SC_EVERSPLIT0005604