Ash leak fuels debate on risks of coal waste
Dec 23 - McClatchy-Tribune Regional News - Josh Flory The Knoxville News
Sentinel, Tenn.
The ash that burst out of a TVA retention pond Monday is the sort of waste
that has gotten scrutiny from federal regulators and lawmakers in recent
months.
The mixture in question was made of water and fly ash, a fine particle
that's one of the byproducts of burning coal to generate electricity. The
ash is collected by scrubbers that aim to clean up emissions from
power-plant smokestacks, and it includes trace elements of materials like
arsenic and lead.
In June, a subcommittee in the U.S. House of Representatives held an
oversight hearing to examine how the government should address the health
and environmental risks of coal combustion waste, including fly ash.
Mary Fox, an assistant professor in the Department of Health Policy and
Management in the Johns Hopkins Bloomberg School of Public Health, testified
at this summer's hearing and said in written testimony that "Risks to human
health are increased if people are exposed to coal combustion waste."
In an interview on Monday, Fox said she was reassured about reports that the
Kingston spill was a release of wet ash because that means it wouldn't have
gotten into the air as dust.
Fox said generally the concern about fly ash is in regard to long-term
exposures -- from leaching into the groundwater, for example -- and said
that when it comes to a spill, the main exposure issues initially will be
for people who are cleaning up the mess.
"If it did impact someone's home," she said, "you'd want them to stay away
from it and not try to be scooping it up with your own broom and dustpan,
that kind of thing. It's not something that you'd want to try and clean up
yourself."
In addition to state and local authorities, the Environmental Protection
Agency also dispatched a coordinator and a contractor to the site. EPA is
currently reviewing its regulation of coal combustion waste, including fly
ash, and one of the documents involved in that process is a 2007 report
which found 24 proven cases of damage to ground or surface water from the
disposal of coal combustion wastes.
Lisa Evans, an attorney with Earthjustice, a California-based nonprofit law
firm, said that in recent years, ash impoundments also have failed in
Pennsylvania and Georgia. "Unfortunately this isn't an isolated instance,"
she said "The surface impoundments are not safe places to keep coal ash in
general."
On the other hand, fly ash can be recycled into something useful. David
Goss, executive director of the American Coal Ash Association, said ash that
meets certain quality standards can be used as a substitute for Portland
cement in concrete, and also has uses including soil and waste
stabilization. Goss indicated that heavy metals are usually found only in
low concentrations, and that they are diluted when stored in liquid.
While he wasn't familiar with the exact details of the Kingston spill, Goss
said that typically the "levels of these concentrations are low enough not
to deem them a public hazard."
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