The Environmental Integrity Project says the federal Environmental Protection Agency has added 18 sites to a list of places where coal ash impoundments are threatening human health by polluting groundwater.

The EPA did not immediately respond to ILN requests for confirmation of the data.

The announcement comes after House Republicans successfully passed a bill in July that would preclude federal regulation of coal ash and leave it to the states.

The bill would stop the EPA from finalizing a bill it proposed to treat coal ash as a hazardous material.

EIP director Eric Schaeffer said the list, which names 38 sites, proved federal regulation by the EPA was needed to monitor companies and prevent further pollution.

“Without federal rules, many states take a ‘see no evil’ approach and do not require the operators of landfills and impoundments to monitor all coal ash pollution,” Schaeffer said in a statement.

“In these cases, there is just not enough data to evaluate these sites as proven or potential damage cases.

“We applaud EPA for confirming instances of coal ash water pollution but federal rules that require common-sense safeguards to monitor, prevent and clean up leaking coal ash dumps are critical and long overdue.”

The EIP said the 18 newly listed sites were located in Indiana, Michigan, Montana, North Carolina, Nevada, New York, Pennsylvania, South Carolina, Tennessee, Texas, Virginia, Wisconsin and West Virginia.

But one of the named companies, DTE Energy, said the report was inaccurate and its Range Road landfill met environmental standards.

DTE spokeswoman Randi Berris told media organization Michigan Live that the EIP pulled data from an April EPA report that referenced a leak in 2006, which was subsequently mitigated by DTE and found to meet environmental standards by Michigan’s Department of Environmental Quality in 2008.