Anniston Star
September 10, 2002

Water board plan would evaporate solvent from water supply

By Sara Clemence
Star Staff Writer

Water officials plan to build a simple but expensive system to remove a suspected carcinogen from Anniston's drinking water source.

The chemical, trichloroethylene, or TCE, is a common solvent used for decades to degrease tanks and clean weapons at the Anniston Army Depot. Over the years, it made its way into local groundwater.

TCE is known to cause cancer in rats and in mice, and has been linked to higher cancer rates in humans.

Working with the Army and its contractors, the Anniston Water Works and Sewer Board plans to install "air strippers" at its treatment plant at Coldwater Springs, said Jim Miller, general manager for the utility.

The device will pump water up into water towers and let it flow back down against a strong current of air, evaporating the TCE.

"We can say with a great degree of certainty that this will solve the problem," Miller said. The method has been proven effective at plants around the country, including one in Huntsville, he said.

"The problem" is that from the 1940s to the 1970s, TCE was improperly disposed of, dumped into open trenches and washed into creeks, eventually making its way into the groundwater beneath the depot.

That groundwater flows into Coldwater Springs, the source of drinking water for Anniston and extra water for Oxford, Hobson City, Weaver and some unincorporated areas of Calhoun County.

The springs and residential wells have never been found to contain dangerous levels of TCE -above the EPA concern level of 5 parts per billion.

But in June Anniston residents learned that a monitoring well a mile south of the depot had TCE levels of 150 parts per billion. The 200-foot well, built by the Army to keep tabs on TCE migration, is halfway between the depot and the springs, near the intersection of Knollton Road and Jim Moore Street.

In July, the EPA sampled the well to confirm the results, and found "no contamination," said Patrick Smith, an environmental engineer for the depot. Nobody is sure why the tests, four months apart, had such different results.

"It may be a wet-season, dry-season type of thing," Smith said. Or it could have to do with the complex way that water travels beneath the ground.

Regardless, "there is a slim chance that the TCEs will just go away" if left alone, Miller said. "Our position is that we're going to go ahead and build the treatment for it."

Miller estimated the cost of the strippers at $3 million, although the final cost is "anybody's guess," since the contract will be put up for public bid.

An Army subcontractor, CH2M Hill, has put forth a design for the air stripping equipment. It will take about six to nine months to build once the money comes through, Miller said. The source of the money is still unclear, but it will likely come from the Army.

Groundwater contamination from the depot has been a concern for nearly 30 years.

The EPA began insisting that the depot comply with environmental regulations in the early 1970s, according to Anniston Star records. In 1977, the EPA and the Alabama attorney general accused the Army of not doing enough to address pollution of Dry Creek, which they thought might flow into Coldwater Springs.

In 1989, part of the Depot was designated a Superfund site, putting the cleanup under EPA
supervision.

Five years later, an Army study confirmed that water from the depot eventually made its way to Coldwater Springs. By 1996, TCE had been found a mile and a half away from the springs, and an emergency plan was drafted for dealing with drinking water contamination. The Army Corps of Engineers is now updating the plan.

Over the years, the Army has spent millions of dollars to address the problem, cleaning up polluted areas and installing water treatment pumps. But the contamination has persisted.

It will continue to persist in the groundwater even after the air strippers are installed. There are still 22 contaminated areas at the depot, for which the Army and EPA are reviewing plans to clean up. Even so, there are some things that may never be fixed.

"We may not be able to get the contamination deep in the bedrock," said Patsy Goldberg, remedial project manager for the EPA. "We don't have the technology to treat groundwater."

Yet Goldberg says that the requirements of the Superfund law have been met, though, because nobody has been exposed to the contamination. The spring and the monitoring well are being sampled on a monthly basis, and levels have never been dangerous.

"In that sense, we have solved the problem," she said.