By MICHELE F. MIHALJEVICH
Indiana Correspondent

AURORA, Colo. — An upcoming ruling by the U.S. Environmental Protection Agency (EPA) on the safety of byproducts from coal-burning power plants could impact farmers, according to an industry representative.

The EPA is reevaluating policies for disposal of these byproducts after a spill in December 2008 at the Tennessee Valley Authority’s Kingston Fossil Plant in Roane County, Tenn. More than one billion gallons of coal fly ash escaped after a dike enclosing a containment pond broke.

“EPA is looking at the coal combustion residue that is left over from the coal-burning process,” said Thomas Adams, executive director of the American Coal Ash Assoc. (ACAA). “They consider anything that doesn’t go out the door as electricity to be residue.”

Of the more than 136 million tons of coal combustion residue generated in 2008, about 17 million tons was in the form of flue gas desulfurization (FGD) gypsum, according to ACAA figures. FGD gypsum is used in drywall, cement and concrete products, and in agriculture, Adams said.

“There are very significant uses in the marketplace for FGD gypsum,” he said. “And as power plants continue to use more scrubbers, there will be more of this material generated. Continuing to find ways to use this material beneficially is going to be important.”

But if the EPA decides to reclassify FGD gypsum as hazardous material, the market could come to a standstill, he said.
“If we get a determination that nothing will change, that there are no new concerns, then this market will continue to grow rapidly and there will continue to be new material available for the market,” he said.

“But with any kind of hazardous ruling, farmers will stop using the product immediately. The market will stop immediately. There would be an impact on small businesses. Some could go out of business.”

FGD gypsum is used by farmers to improve soil quality and control erosion, said Darrell Norton, a research soil scientist with the USDA’s Agricultural Research Service’s National Soil Erosion Research Laboratory at Purdue University. Technology has improved today’s FGD gypsum as compared with earlier versions, said Norton, also an adjunct professor at Purdue.

“More efficient scrubbers have actually made FGD gypsum cleaner. It’s much more benign than it used to be and fly ash is really the problem. And there is virtually no fly ash in modern FGD gypsum,” he said.

FGD gypsum contains small amounts of several chemicals, including mercury and arsenic, said Warren Dick, a professor of soil science with The Ohio State University School of Environment and Natural Resources in Wooster. EPA is undertaking a complete risk assessment, he said.

“There don’t seem to be any red flags that show we shouldn’t or couldn’t use it,” he added. “The EPA could decide to label all coal-burning byproducts as hazardous, they could separate them and declare some hazardous and others not or they could leave the current rule as is.”

Norton is serving on a committee working with the EPA on the risk assessment. From his understanding, a decision on FGD gypsum and other coal-burning byproducts has been delayed until the first or second quarter of this year.

“We’re trying to relay our research findings to them,” he said. “They’re looking at these materials for the third time, which were specifically exempted in the original Clean Air Act. The safety (of FGD gypsum) has gotten better because of technology, not worse. The EPA and others have studied this to death in the past. There’s nothing new under the sun and gypsum has been used for a long time.”

Dick agreed. “(FGD gypsum) isn’t new, it’s been used for thousands of years,” he said. “And FGD gypsum is completely different than fly ash and bottom ash. I can’t think of a single case where there’s been an issue with toxicity.”

Use of FGD gypsum is strong in the southeastern United States, especially by peanut farmers, and in the western U.S. where soils contain sodium, Norton said. In the Midwest, more corn and soybean farmers are becoming aware of it as a potential tool.
“Interest is growing by leaps and bounds, but use is limited by their ability to get it at an affordable price,” he said.

Contrary to recent articles on this subject, Norton said neither the USDA nor the EPA are trying to push farmers to use this material, but only to consider it when it can help with a problem they have with their soil.

Use of FGD gypsum can enhance performance and soil quality, but as with any soil amendment, farmers need to do some research before they use it, Dick said.

“They need to know what is the proper rate on a specific soil for a specific crop,” he said. “They need to match the need with the treatment. It’s not a panacea. It can’t solve everything.”
While FGD gypsum, fly ash and bottom ash are all byproducts of coal combustion, Dick said it’s incorrect to assume they are the same.

“You can’t treat these as likes. It’s not even comparing apples to apples. If you use (FGD gypsum) and apply it carefully like any other soil amendment, it’s perfectly safe,” he explained.