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The Fly Ash Threat

The Fly Ash Threat

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    An aerial image before the Kingston, Tenn., ash slide on Dec. 22, 2008.

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    On Dec. 30, 2008, the Emory River is inundated with coal ash slurry after a containment pond ruptured.

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    Simple storage and loading would require new permitting and safety procedures if the EPA classifies fly ash as a hazardous material.

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    A microscopic view of the controversial material.

First, any hazardous designation is likely to greatly reduce using fly ash in concrete. ACI cautioned the EPA that a hazardous designation would likely result in fly ash being removed from all specifications and standards, including the ACI 318 Building Code Requirements for Reinforced Concrete. ACI concluded that “EPA should not risk harm to the environment and material benefits of fly ash use in concrete when addressing the impoundment requirements for fly ash, nor abrogate the ability to make effective and safe use of this industrial byproduct.”

Producers wanting to use fly ash would have to adopt restrictive safety procedures for employees. All current air operating permits for facilities would have to be modified.

The American Coal Ash Association (ACAA) suggests that one potential outcome of a hazardous waste classification is that the electric utilities, which generate fly ash as part of their pollution-control efforts in treating flue gases, will simply stop selling fly ash since they would also be likely to attract liability.

If any of these results occur, the cost of concrete will surely skyrocket. In a letter to the EPA's Jackson, NRMCA President Robert Garbini wrote, “Eliminating the availability of fly ash would result in cost increases that could render concrete noncompetitive.”

Another implication, ECOS says, would be to overwhelm hazardous waste landfills across the nation with 135 million tons of CCPs, while today they handle only about 2 million tons of hazardous materials. ECOS executive director R. Steven Brown concluded in a letter to the EPA that this could have the perverse effect of reducing the treatment of materials that are truly hazardous, unlike fly ash which has never been shown to be hazardous. Forty eight of the 50 state environmental agencies have come out against the hazardous designation. (The other two have no coal fired power plants.)

Playing politics

To many, the EPA's response to the coal ash dam failure has been based not on scientific evidence but on politics and a desire on the part of some environmental groups to completely eliminate the burning of coal for electricity generation. The ACAA predicts that the agency will need to take action to satisfy environmental activists who are not looking at the science.

For example, the greatest environmental concern with fly ash has always been the concentrations of heavy metals, such as mercury, cadmium, and arsenic. These materials could potentially leach out of concrete made with fly ash. But TVA's testing shows that the concentrations in the Kingston ash are well below anything that could be considered hazardous. In fact, it reports that “the concentrations of most metals in the ash are within the range of concentrations found in natural soils in Tennessee.”

Bruce Boggs, vice president of research and development for Headwaters, says that tests on fly ash before buying it from an electric utility have never yielded results that would qualify the material as a hazardous waste.

Still, news reports often cite heavy metals in fly ash as a grave danger. For example, Environmental activist Erin Brockovich wrote in The Brockovich Report that, “Fly ash apparently contains silicon dioxide and calcium oxide, as well as trace concentrations of heavy metals. In other words, coal ash is nasty stuff to have floating around in your river, air, and drinking water.”

But silicon dioxide and calcium dioxide are sand, and “trace concentrations” are not a scientific analysis and do not necessarily result in such “nasty stuff.” Actually, fly ash concrete has been used for many years to make impermeable water tanks and pipes, and no elevated concentrations of metals have ever been measured in the water.

The concrete and cement industries have mounted a major effort to combat this threat. Their message is that the problems with coal ash disposal can be addressed without restricting the beneficial uses of fly ash.

Anyone in the concrete industry can contact his congressional representatives and senators or EPA Administrator Jackson and request that they look at the facts rather than the hysteria. No one has ever been harmed by using fly ash, but the EPA's actions could harm many.

William D. Palmer Jr. is with Complete Construction Consultants and is the former editor in chief of Hanley Wood's CONCRETE CONSTRUCTION magazine. E-mailwpalmer@cee3.com.