Toxic Legacy: Cleanup Efforts Underway at Decommissioned New Mexico Power Plant

As of October 7, 2025, state environment officials in New Mexico have been increasing their efforts to investigate potential pollution around the site of the recently decommissioned San Juan Generating Station, a coal-fired power plant that operated for nearly 50 years.

The officials have been testing the soil and water in the area, trying to track historic spills, coal ash disposal, and other pollutants. They have installed additional monitoring wells to better understand the scope and extent of any contamination. The state's environment department will be presenting their findings, including data from a recent groundwater investigation, at a public meeting on October 7, 2025.

The San Juan Generating Station, along with the neighboring Four Corners Generating Station, was considered one of the largest single sources of pollution in the U.S. as recently as 2014. The plant permanently closed in 2022 and has been under demolition since August 2024. However, the decades of coal waste disposal have left a potential legacy of pollution that state officials are now working to address.

In a July 2025 letter, environment officials requested the plant's previous owner, Public Service Company of New Mexico (PNM), to produce a plan to reduce pollution by the end of September 2025. PNM has requested an extension, and the plan is now due to state officials by November 26, 2025. The public meeting will provide more details on the nature of any contamination and the state's plans for further cleanup.