Company: AILIM
Filing Date: 2025-08-04
Form Type: 10-Q
Source: 0001002910-25-000112
Chunk: 98

Company: Ameren Illinois Co
Filing Date: 2025-08-04
Form: 10-Q
Item: Part I, Item 1
Chunk 98
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 gas emissions, which was the basis for implementing greenhouse gas emissions standards. The EPA expects to issue final rules by the end of 2025.

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MATSIn April 2024, the EPA revised the MATS by establishing a more stringent standard for emissions of particulate matter, as well as requiring the use of continuous emissions monitoring systems. In April 2025, the EPA granted Ameren Missouri a two-year extension of the compliance deadline for the Labadie and Sioux energy centers, which is now set for July 2029. In June 2025, the EPA issued a proposed rule to repeal the April 2024 revisions to the MATS. The EPA expects to issue a final rule by the end of 2025.NSPSIn November 2024, the EPA issued a proposed rule revising the NSPS to limit emissions of NOx from natural gas-fired stationary CTs. If adopted as proposed, the rule would require such natural gas facilities which began construction after December 13, 2024, to install certain pollution control equipment to limit emissions of NOx. In addition, the EPA proposed to maintain the current limits for SO2 at such natural gas facilities. In June 2025, the EPA issued a proposed rule to repeal all greenhouse gas emissions standards for fossil fuel-fired power plants, including the NSPS. The EPA expects to issue a final rule by the end of 2025.Clean Water ActAll of Ameren Missouri’s coal-fired and nuclear energy centers are subject to Clean Water Act requirements to identify measures for reducing the number of aquatic organisms impinged on a power plant’s cooling water intake screens or entrained through the plant’s cooling water system. Cooling water intake requirements are implemented by state regulators through the permit renewal process of each power plant’s water discharge permit. Permits for Ameren Missouri’s coal-fired and nuclear energy centers have been issued or are in the process of renewal.CCR ManagementThe EPA’s 2015 CCR Rule establishes requirements for the management and disposal of CCR from coal-fired power plants and has resulted in the closure of surface impoundments at Ameren Missouri’s energy centers, with closures of surface impoundments in process at its Sioux Energy Center and retired Meramec Energy Center. Ameren Missouri plans to substantially complete the closures of remaining surface impoundments by the end of 2026. Ameren Missouri’s CCR management compliance plan includes installation of groundwater monitoring equipment and groundwater treatment facilities. In April 2024, the EPA revised the CCR