Originally created 10/10/01

Cement slurry to be tested in tar cleanup



A three-year, $50 million cleanup of toxic coal tar at a former gas plant on Eighth Street will employ an experimental technology involving the injection of cement into contaminated soil.

Shawn Davis, the spokesman for the team undertaking the cleanup at the Atlanta Gas Light property, said similar technology is being used successfully at a former manufactured gas site in Macon.

"It's like a recipe for baking a cake," he said. "We know the technology works, but it's a matter of getting the recipe right."

The gas plant - bounded by Eighth Street, Walton Way and the Augusta Canal - operated from 1852 to 1955. Coal tar from the gas-making process seeped into soil and water over the decades.

Coal tar contains cancer-causing materials such as benzene and naphthalene, and Georgia's Environmental Protection Division is requiring an extensive cleanup of surrounding soil and ground water.

Mr. Davis said the technology to be used in part of the area is called solidification. The pilot phase will involve removing 3,650 cubic yards of soil to test the use of cement slurry underground.

The slurry, once hardened, creates a barrier that prevents further contamination of subterranean aquifers. Contamination has spread far from the site to areas beneath the Augusta-Richmond County Civic Center and Bell Auditorium.

Next year, broader cleanup plans involve the excavation of 122,000 cubic yards of soil and the use of solidification to treat 220,000 cubic yards of soil as deep as 30 feet.

Other remediation methods at the site will involve the pumping and treatment of contaminated ground water, said Scott Keating, project director for RETEC, the environmental company conducting the cleanup.

Much of the contaminated soil will be disposed of in landfills in Savannah and Winder, Ga., he said. Soil remediation will be under way through 2004 but ground-water treatment programs could last as long as 30 years.

The cleanup plan was presented Tuesday night during a sparsely attended public hearing in Augusta.

Reach Robert Pavey at (706) 868-1222, Ext. 119, or rpavey@augustachronicle.com.

Once contaminated soil has been removed, work to revitalize the area with housing, parks and improvements to the Augusta Canal will begin.