The Environmental Protection Agency is moving to preempt future coal ash spills and also turn coal waste into useful construction material.
The US Environmental Protection Agency (EPA) is moving to preempt future coal ash spills and also turn coal waste into useful construction material.
Responding to last year’s massive coal ash spill at a Tennessee Valley Authority facility in Kingston, Tennessee, the U.S. Environmental Protection Agency says it has drawn up a slew of safety measures.It will gather critical coal ash impoundment information from electrical utilities nationwide, conduct on-site assessments to determine structural integrity and vulnerabilities, order cleanup and repairs where needed, and develop new regulations for future safety.
“Environmental disasters like the one last December in Kingston should never happen anywhere in this country,” said EPA Administrator Lisa P. Jackson. “That is why we are announcing several actions to help us properly protect the families who live near these facilities and the places where they live, work, play and learn.”
The December 2008 release of coal ash from TVA’s Kingston, Tennessee facility flooded more than 300 acres of land, damaging homes and property. Coal ash from the release flowed into the Emory and Clinch rivers, filling large areas of the rivers and killing fish. TVA cost estimates for the clean-up range between $525 million and $825 million, which does not include long-term cleanup costs.
The EPA has requested that electric utilities that have surface impoundments or similar units provide information about the structural integrity of their units. The agency will visit many of these facilities to see first hand if the management units are structurally sound.
It will also require appropriate remedial action at any facility that is found to pose a risk for potential failure.
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EPA is also moving forward quickly to develop regulations to address the management of coal combustion residuals. EPA anticipates having a proposed rule ready for public comment by the end of the year.
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" Coal supplies more than half of the electricity consumed by Americans, according to the U.S. Department of Energy. Just over 1 billion tons of coal were burned for electric power in the United States
About 43 percent of the 131 million tons of coal combustion products including fly ash, bottom ash and boiler slag generated in 2007 found beneficial uses, according to the American Coal Ash Association, based in Aurora, Colorado.
About 44 percent of fly ash found uses, mostly as a substitute for some of the portland cement in concrete, a use the EPA especially encourages because any heavy metals in the ash are trapped forever. (Concrete is composed of sand, gravel and portland cement to hold it all together.)
Fly ash makes concrete stronger and less porous, as well as generally less expensive, said Colin Lobo, engineering vice president of the National Ready Mixed Concrete Association, the concrete industry's largest trade group.
Production of portland cement releases large amounts of the greenhouse gas carbon dioxide, so reducing its use helps the environment, chemist Chett Boxley said.
"Not only does the concrete become greener in that sense, but it performs better," he said.
California's Department of Transportation is so sold on fly ash's benefits that it requires contractors to replace 15 percent to 35 percent of the portland cement in road concrete with the ash, said Vijay Jain, Caltrans' head of engineering.
Another useful coal combustion product is gypsum.
The process that smokestack "scrubbers" use to reduce nitrogen oxide and sulfur dioxide emissions creates high-quality synthetic gypsum, said Robert E. Williams, spokesman for U.S. Gypsum Co., maker of Sheetrock brand wallboard.
Scrubbers at electric utility PPL Corp.'s Montour plant near Washingtonville, Pennsylvania, generate 500,000 tons of gypsum annually, plant manager Michael Munroe said.
PPL pipes every bit of it to a new U.S. Gypsum plant right across the road, supplying it with all the gypsum it needs to make 955 million square feet of wallboard a year, said Scott Shaffer, manager of the gypsum plant.
"It's a terrific environmental win-win for everybody involved," Williams said. "You're cleaning the air and then avoiding a landfill, and using it as a useful input for a useful product."
The PPL plant also markets all of its ash for beneficial reuse, spokesman George Lewis said.
We Energies, a utility in Wisconsin, goes PPL one better on that score:
"We're pretty much at the point where we're selling it all and, depending upon the marketplace, actually going into the landfills where we had previously landfilled ash and using that," We Energies spokesman Brian Manthey said.
Still, "the volume of coal ash we're creating is far greater than we could ever put into asphalt and drywall and concrete blocks; the volume is staggering," said Mary Anne Hitt, the deputy director of the Sierra Club's Move Beyond Coal Campaign.
Some other environmentalists too are skeptical.
Lisa Evans, lead attorney for environmental group Earthjustice's coal project, warned that improperly handled ash could leach arsenic, lead, chromium, selenium and other toxic materials into ground and drinking water.
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