'Nearby, the Emory River had been choked by a gray film. Gray framed the shore for miles, lining boat houses, docks, and edging the forest where it met the water. It was obviously a foreign addition since the color was so different from the river water and it appeared to sit on top of the water. Since it was Christmas, all appeared quiet.' The Tennessee Coal-Ash Spill, in Pictures, photo by Dorothy Griffith

By Scott Barker
Posted March 14, 2010 at midnight Federal regulators say it’s technologically impossible to remove all the coal ash from the Emory River and an undetermined amount will remain after the cleanup of the Kingston ash spill is complete. According to a memorandum written by Leo Francendese, who oversees the emergency cleanup operation for the U.S. Environmental Protection Agency, the removal of ash from the Emory River has entered its final stage – dredging along the riverbed. Francendese writes that the goal is to remove as much ash as possible while disturbing sediments as little as possible. Francendese’s memo, combined with a memo from Steve Scott of the U.S. Army Corps of Engineers, raises the possibility that officials also might not remove ash that has migrated from the Emory to the Clinch River and Tennessee River portions of Watts Bar Lake. Because dredging stirs up the sediments and ash, Francendese writes, some of the material – between 5 and 20 percent – will remain suspended in the water and then settle back on the riverbed after the dredges move on. “It is worth noting, that 100 percent removal is never achieved due to the resuspension and resettlement effect,” Francendese writes. Steve McCracken, the Tennessee Valley Authority’s cleanup project manager, said in an interview that doesn’t run counter to TVA’s stated goal of leaving the area better than it was before the Dec. 22, 2008, spill, which dumped 5.4 million cubic yards of coal ash sludge from the federal utility’s Kingston Fossil Plant into the Emory River and surrounding area. “When we’re done, the water quality, the habitat and the recreational use will be better than it was before,” McCracken said. … Scott’s memo outlines the results of the Corps of Engineers’ initial evaluation of the risks associated with ash that has flowed downstream from the spill site into the Clinch and Tennessee rivers. The ash, a byproduct of coal combustion, contains heavy metals like arsenic, lead, selenium and mercury. An estimated 165,000 cubic yards of ash migrated from the spill site during heavy storms in May, December and January, Scott writes, with the vast majority being released in May before dredging the Emory’s river channel had an effect. Scott writes that downstream ash will mix with sediments. About 346,000 tons of sediments flow into Watts Bar Lake every year, he writes. Scott asserts that the resulting mix would reduce arsenic concentrations over time. “Therefore after approximately 5 years, the fly ash residuals that transport below the site will potentially be diluted to background levels due to mixing and burial with inflowing native sediments,” Scott writes. … “However,” Scott cautions, “the long term stability of fly ash and associated constituents is relatively unknown at the time.” …

Some ash to remain in river: Complete removal of material not feasible, federal regulators say