The federal government promoted some uses of coal ash, including wallboard or filler in road embankments, without properly testing the environmental risks, according to a report from the Environmental Protection Agency's inspector general.
The inspector general's report released Wednesday said sites where coal ash was used for earthworks, like road embankments or berms, "may represent a large universe of inappropriate disposal applications with unknown potential for adverse environmental and human health impacts."
The EPA is considering imposing stricter regulations for coal ash, or fly ash, a byproduct of burning coal at power plants. The rule changes were prompted by a 2008 environmental disaster at a Tennessee power plant that released more than 5 million cubic yards of ash into a river and nearby lands.
The agency has said coal ash contains arsenic, selenium, lead and mercury in low concentrations, and those contaminants can pose health risks if they leach into groundwater.
Agency officials relied on state programs to approve beneficial uses of coal ash, the report said, and the federal agency never implemented its own plans set up in 2005 to determine environmentally safe uses. The report recommended the EPA establish new guidelines to determine beneficial uses, and investigate whether action is needed at sites where the substance has been used as structural filler.
Coal ash recyclers and manufacturers that use it have argued that tougher federal regulations would place a stigma on the substance and hinder efforts to reuse some of the 130 million tons produced at U.S. coal-fired power plants each year.
"We have many decades of beneficial use of these products with no damage cases that have resulted from this beneficial use," said Thomas Adams, executive director of the American Coal Ash Association, in Aurora, Colo.
The EPA halted a program last year that promoted beneficial uses of coal ash, and took down a related website. The program, called the Coal Combustion Products Partnership, was started in 2001 with a goal of increasing the recycling of coal ash for use in other applications.
Adams said he was concerned the inspector general's report is a harbinger of EPA plans to impose tougher standards on the substance.
"You can kind of read between the lines that they truly don't support recycling anymore," Adams said.
The EPA's proposed rule would deem coal ash hazardous waste, bringing it under direct federal enforcement. Under a second option, favored by the industry, the ash would be considered non-hazardous and regulation of standards set by the EPA would be left to the states. Several public input hearings held around the country last year on the proposed changes attracted hundreds of citizens, activists and energy and manufacturing workers.