Of the 155 waste sites, more than one-third were close or very close to significant human populations; two-thirds were near or very near key waterways, Madonna found. About half of the sites were coal-ash surface impoundments (lagoons).
“You have toxic wastes leaking into water bodies from probably every single one of these lagoons,” Madonna says. “It’s a huge mess.”
Little is known about coal-ash storage sites, which are lightly regulated by states and exempt from federal hazardous-waste regulations. Many are decades old, which increases the potential for leakage and containment failure, experts and environmentalists say.
Lisa Evans, an attorney for Earthjustice, an environmental group, says the EPA underestimates the problem. “Most impoundments are not monitored at all,” she says. “The list of sites identified by the EPA in 2007 is far from comprehensive.”
Needed: impermeable liners for waste sites
An earlier EPA report to Congress in 1999 showed that about three-quarters of some 300 active surface impoundment sites were unlined, Ms. Evans says. Of those that were lined, most were probably lined with clay, which is an inadequate barrier to toxic metals and invites contamination oflocal ground water, says Charles Norris. Mr. Norris is head of Geo-Hydro Inc., a Denver-based consulting company that has analyzed the hydrogeology of such structures. An impermeable composite (plastic) liner is what’s required, he and others say.
The problem is perhaps most acute among nearly 100 coal-ash storage lagoons in two dozen states across the country. Many of these ponds are far larger and far more toxic than the one that burst at the Tennessee Valley Authority’s Kingston power plant at Harriman, Tenn., on Dec. 22.