Document RJ9nb9qzgLy9X3Vg3GZbmqYOB

Message From: Sent: To: Subject: AirAction [/O=EXCHANGELABS/OU=EXCHANGE ADMINISTRATIVE GROUP (FYDIBO HF23SPDLT)/CN=RECIPIENTS/CN -FA78B98923384078995E04A73D258D83-AlRACTION] 3/31/2025 2:34:02 PM Culligan, Kevin [Culligan.Kevin@epa.gov] FW: Presidential Exemption: Clean Air Act NSR and NNSR Requirements: Thunderhead Dekalb Co, IL Data Center Power Project From: Brennan Zaunbrecher <brennan@thunderheaddg.com> Sent: Friday, March 28, 2025 3:29 PM To: AirAction <AirAction@epa.gov> Subject: Presidential Exemption: Clean Air Act NSR and NNSR Requirements: Thunderhead Dekalb Co, IL Data Center Power Project Caution: This email originated from outside EPA, please exercise additional caution when deciding whether to open attachments or click on provided links. I To Whom It May Concern: Thunderhead Energy Solutions LLC requests a two-year Presidential exemption from certain Clean Air Act requirements for our 500MW behind-the-meter natural gas power facility supporting critical data center infrastructure in Dekalb County, IL. Emissions standards subject to exemption request: New Source Review (NSR) permitting requirements, Non-attainment New Source Review (NNSR) requirements, Title V Operating Permit timeline requirements, and New Source Performance Standards (NSPS) for Stationary Combustion Turbines (40 CFR Part 60, Subpart KKKK) Facility: Thunderhead Data Center Power Project utilizing Solar Turbines (Caterpillar) Titan-130 industrial gas turbines with EnergyLink SCR technology (Best Available Control Technology, "BACI") for emissions reduction Duration: Two-year exemption to allow expedited construction and operation Justification: Current permitting timelines create critical delays and/or outright roadblocks for essential digital infrastructure. Despite employing advanced emissions control technology, the standard permitting process would prevent timely deployment of urgently needed computing capacity and ultimately limit the operable electric generation capacity via NOx, CO, VOC, particulate matter, sulfuric acid, and sulfur dioxide emissions limitations. There is no commercial technology to completely eliminate NOx, CO, VOC, particulate matter, sulfuric acid, or sulfur dioxide emissions from gas-fired National security relevance: The facility will support enterprise cloud and AI computing infrastructure essential to U.S. national security interests, including classified government workloads and critical AI development. Current grid constraints in Dekalb County, IL prevent timely utility-scale power deployment, while our behind-the-meter natural gas solution can deliver 500MW in 18-24 months, significantly accelerating national security-related computing capacity. This bridge natural gas solution represents the only viable path to rapidly deploy the power capacity required for next-generation computing infrastructure critical to maintaining L.S. technological leadership. We Sierra Club FOIA 2025-EPA-04883 ED_018388_00005682-00001 SC_EVERSPLIT0006415