The Environmental Protection Agency is proposing to roll back federal coal ash cleanup rules, raising concerns about groundwater contamination at dozens of coal plants and waste dumps across the Mountain West.
In a region where many rural communities rely on groundwater as their main drinking water source, along with agriculture and industry, even small increases in contamination risk can have outsized impacts, especially where there are few alternative water supplies.
Coal ash — the toxic byproduct left after coal is burned for electricity — is often stored in ponds or landfills near power plants. Under current federal rules, these sites are required to monitor nearby groundwater and take corrective action if contamination exceeds federal safety limits.
Across the Mountain West, coal ash sites are spread widely: Colorado has about 12, Utah and Wyoming each have six, Arizona has five, Nevada has four, and New Mexico has three. Idaho has none identified in this dataset.
Monitoring data links coal ash ponds and landfills to groundwater contamination at multiple locations across the region. In some cases, testing has found toxic metals like arsenic, boron, lithium, and radium.
"It's a whole alphabet soup of dangerous chemicals," said Lisa Evans, a senior attorney with Earthjustice, an environmental law group pushing back on the EPA proposal. "When coal ash gets wet, the water takes those hazardous contaminants and leeches it out of the coal ash into the groundwater, which could be used for drinking or irrigation."
Evans said coal ash becomes especially dangerous when it comes into contact with water, and that reducing oversight could make cleanup more difficult. Even after coal plants shut down, coal ash can remain a long-term source of pollution if left in place.
"This proposal would roll back key health and environmental safeguards nationwide," Evans said. "It would open the door to more pollution from coal ash dumps across the country."
The Environmental Protection Agency is accepting public comments through June 12 and plans to hold an online hearing May 28.
This story was produced by the Mountain West News Bureau, a collaboration between KUNR, Wyoming Public Media, Nevada Public Radio, Boise State Public Radio in Idaho, KUNC in Northern Colorado, KANW in New Mexico, Colorado Public Radio, KJZZ in Arizona and NPR, with additional support from affiliate newsrooms across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting and Eric and Wendy Schmidt.
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