By Rick Callahan
Indianapolis — Federal officials are encouraging farmers to spread a chalky waste from coal-fired power plants on their fields to loosen and fertilize soil even as the officials consider regulating coal wastes for the first time.
The material is produced by power plant scrubbers that remove acid rain causing sulfur dioxide from plant emissions. A synthetic form of the mineral gypsum, it also contains mercury, arsenic, lead and other heavy metals.
According to the U.S. Environmental Protection Agency, those toxic metals occur in only tiny amounts that pose no threat to crops, surface water or humans. But some environmentalists say too little is known about how the material affects crops, and ultimately human health, for government officials to suggest that farmers use it on their land.
“Basically this is a leap into the unknown,” said Jeff Ruch, executive director of Public Employees for Environmental Responsibility. “This stuff has materials in it that we’re trying to prevent entering the environment from coal-fired power plants and then to turn around and smear it across ag lands raises some real questions.”
With coal wastes piling up around the coal-fired plants that produce half the nation’s power, the EPA and U.S. Department of Agriculture began promoting what they call the wastes’ “beneficial uses” during the Bush administration.
Part of that push is to expand use of synthetic gypsum — a whitish, calcium-rich material known as flue gas desulfurization gypsum, or FGD gypsum.
The Obama administration has continued promoting FGD gypsum’s use in farming even as it drafts a coal waste rule in response to a spill from a coal ash pond near Knoxville, Tenn., one year ago Tuesday. Ash and water flooded 300 acres, damaging homes and killing fish in nearby rivers. The cleanup is expected to cost about $1 billion.
The EPA is expected to announce its proposals for regulation early next year, setting the first federal standards for storage and disposal of coal wastes.
EPA officials declined to talk about the agency’s promotion of FGD gypsum before then and wouldn’t say whether the draft rule would cover it.
Instead, the agency released a statement saying the heavy metals in the material are far less than the amount considered a threat to human health. Field studies have shown that mercury, the main heavy metal of concern because it can damage development of the human nervous system, doesn’t accumulate in crops or run off fields in surface water at “significant” levels, according to the statement.
“EPA believes that the use of FGD gypsum in agriculture is safe in appropriate soil and hydrogeologic conditions,” according to the statement.
Eric Schaeffer, executive director of the Environmental Integrity Project, which advocates for more effective enforcement of environmental laws, said he’s not overly worried about FGD gypsum’s use on fields because research shows it contains only tiny amounts of heavy metals. But he said federal limits on the amounts of heavy metals in FGD gypsum sold to farmers would help allay concerns.
“That would give them assurance that they’ve got clean FGD gypsum,” he said. “The farmers don’t want to get a bad batch.”