Why the Nation's Biggest Environmental Distaster May Be About to Get Worse

By Kelly Hearn, The Nation. Posted May 20, 2009.

Pressure to Dredge

Despite warnings that the dredging may trigger a major toxic event, the TVA, backed by federal and state officials, is following through with its plans. "There apparently has been horrendous pressure to dredge at any costs," said Bryce Payne, an independent environmental consultant who has been working on fly ash for more than fifteen years. "But the fish and similarly vulnerable biota in the Emory and Clinch River system simply will not be able to tolerate additional selenium."

Payne, who is considered by some to be the nation's top expert on coal ash issues, has led a behind-the-scenes effort -- alongside some of the nation's top selenium scientists -- to convince the TVA that the selenium problem is a loaded gun, that the authority's water-monitoring plan is faulty on scientific principle and that alternatives to dredging may well help avoid serious damage caused by selenium.

In two recent conference calls with dozens of officials and experts, Payne laid out one alternate plan to avoid floods, by digging a bypass channel around the ash dam. Payne proposes alternate ash removal approaches, including one that calls for adding lime, a relatively inert substance that causes the ash to solidify in place in the river, then removing the ash in solid form, essentially locking in selenium loads. The downside: the technique has been demonstrated only on a smaller pilot scale. On March 20, Paul Sloan, deputy commissioner at the Tennessee Department of Environment and Conservation, sent an e-mail to Payne and over a dozen people, including TVA and federal officials, who had been on one of the conference calls. "We believe the risks of selenium contamination are manageable with proper planning and attention, and that the risks of delaying ash removal outweigh the risk that might associate with selenium," Sloan wrote. He said that the EPA and TDEC will carefully monitor river water near the dredge operation for selenium contamination and added that the agencies plan to "follow up on fish testing samples."

Federal officials, for their part, stress that they will monitor the river water closely, and shut down the multimillion-dollar dredging operation if too much selenium is found. "If selenium or other constituents we are monitoring exceed regulatory limits, the dredging will be stopped so we can determine appropriate next steps," said Dana Tulis, deputy director of the EPA's Office of Emergency Management.

Slippery Chemistry?

Scientific experts say that monitoring regimes put in place by the authority, as well as state and federal officials, may not be able to detect pulses of selenium, thanks to its odd chemistry, which may allow it to evade water monitoring.

Payne, who has a doctorate in soil science, told Sloan in an e-mail that the proposed water-monitoring scheme was of little use, since one of selenium's two relevant chemical forms is a toxic compound called selenite, which gets absorbed by secondary chemicals in coal ash and moves with the dredged ash, not in the water. Later, when exposed to more air, the selenite turns into selenate, another toxic form of selenium; it is not held by the secondary minerals and then moves on to take its toll on aquatic life. To make matters worse, according to Payne and others, the analytical methods used in the official monitoring efforts are simply not good enough to detect the trace amounts of selenium likely to be seen in the water. (The TVA said in an April 21 e-mail that official water-monitoring sites had detected no exceedances of selenium since dredging began. The statement also said the monitoring sites were designed to measure all forms of selenium.)

Payne, who has offered his consulting services to the TVA and state regulators, wants officials to understand why so many of the best-laid plans could be heading toward disaster. In the March 20 e-mail to Sloan, he questioned the TDEC's assumptions, pressed the agency to make its selenium data public and criticized Tennessee's water-quality standards as too permissive regardingselenium. He zeroed in on the state agency's pledge to follow up on fish tissue studies. The problem with fish tissue tests, he explained, is that selenium "bioaccumulates," inching its way into fish and animals over months and years, not days and weeks. If you find selenium in high concentrations in fish tissue, the theory goes, you're already in trouble. "[Fish tissue data] will not tell you how much more selenium may still come after you have finally detected that a threatening amount was there in the first place," he told Sloan. In a telephone interview, Payne said that the threat was hard to detect: "Selenium, by its nature and chemistry, will sneak up on us," Payne says. "It's like the frog in the pot of slowly heating water."

See more stories tagged with: water, water pollution, tva, coal spill, selenium

Kelly Hearn is a correspondent to National Geographic News and The Christian Science Monitor. His work has been funded by The Pulitzer Center for Crisis Reporting and The North American Congress on Latin America. A former UPI reporter, he has published in The Nation, Grist, High Country News, The Washington Times and World Politics Watch. He is a frequent contributor to Alternet.

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