Newly released data shows a high cancer risk for up to one out of every 50 Americans living near more than 200 unlined and clay-lined coal ash landfills and slurry ponds such as the TVA Kingston ash sludge landfill that collapsed into the Emory River in December.

Tennessee, Georgia and Alabama have 31 such landfills and slurry ponds — all on or near major waterways, according to the seven-year-old data released in March by the Environmental Protection Agency.

Tennessee and Georgia each have 11 such landfills, according to an analysis of the data by two national environmental groups, the Environmental Integrity Project and Earthjustice. One is clay lined, and the remaining 21 are unlined.

The data, part of an EPA risk assessment partially released in 2007, found that the risk was greatest both for human health and ecosystems near unlined waste units. The risk fell to one out of 133 Americans for clay-lined ash pits, according to the EPA.

EPA’s “acceptable” cancer risk is one in 100,000.

Tennessee Valley Authority officials consistently have said the ash spilled in December from the utility’s Kingston Fossil Plant wet landfill in Harriman, Tenn., and in January from its Widows Creek pond in Stevenson, Ala., is non-hazardous.

In a prepared statement, Joe Hoagland, TVA’s Vice President of Environmental Science, Technology & Policy, said the EPA’s 2007 Human and Ecological Risk Assessment was a draft report and not the final version.

“We look forward to that final assessment from EPA, and we will work with regulatory authorities and others to address any issues,” he said. “Meanwhile, TVA is complying with all environmental rules and regulations in all of its operations and in the storage of coal combustion by-products.”

EPA Press Secretary Adora Andy said the Kingston spill spurred regulators to resume work on the coal ash issue, and the agency expects to propose new regulations later this year.

“Since last year’s coal ash spill at a Tennessee Valley Authority facility in Kingston, Tenn., the EPA has executed new efforts to prevent future threats to human health and the environment,” she said. “EPA is expeditiously evaluating all liquid coal impoundments in the country to determine whether they raise the type of structural integrity issue that led to the TVA spill.”

After the spill, regulatory and independent testing have found differing and high levels of toxicity in the spilled waste and raw water where the two spills occurred.

Lisa Evans, director of Earthjustice, called for wet coal ash ponds and landfills to be phased out in five years.

“Given what the (EPA) already knows, coal ash ponds should be inventoried, monitored and cleaned out,” she said.

Ms. Evans said Earthjustice requested the recently released data years ago but obtained it only after the Obama administration was in place.

On Thursday, the same day the new report was released, TVA announced it had begun a limited, two-week test of the removal by rail of spilled fly ash from the Kingston plant in Harriman.

“This is the first time we have transported any ash offsite,” said TVA spokeswoman Barbara Martocci.

In a prepared release, TVA officials said permanent disposal plans for ash from the Kingston ash spill have not yet been made, but the test, with oversight by the EPA and the Tennessee Department of Environment and Conservation, will ensure the utility uses “the best possible processes.”

The waste is being taken to non-hazardous, state-regulated landfills outside of Tennessee, according to TVA, and federal and state regulators must approve TVA’s final plans for off-site disposal.