GEOCHEMSTRY OF AN ABANDONED LANDFILL CONTAINING
COAL COMBUSTION WASTE: IMPLICATIONS FOR REMEDIATION
Christopher Barton 1, Linda Paddock2, Christopher
Romanek2,3, and John Seaman2
1USDA Forest Service, Center for Forested Wetlands Research,
c/o Savannah River Ecology Laboratory, Drawer E, Aiken, SC 29802
2University of Georgia, Savannah River Ecology Laboratory,
Drawer E, Aiken, SC 29802
'3Department of Geology, University of Georgia, Athens, GA
30602
1. ABSTRACT
The 488-D Ash Basin (488-DAB) is an unlined, earthen landfill containing
approximately one million tons of dry ash and coal reject material at
the U.s. Department of Energy's Savannah River Site, SC. The p~tic nature
of the coal rejects has resulted in the formation of acidic drainage (AD),
which has contributed to groundwater deterioration and threatened biota
in adjacent wetlands. Establislunent of a dry cover is
being examined as a remedial alternative for reducing AD generation within
this system by minimizing the contact of oxygen and water to the waste
material. To determine the potential benefit of a cover on pore water
chemistry, a series of flow-through column experiments were performed
under varying environmental conditions using materials from the site.
The experiment was designed to demonstrate the influence of temperature,
gaseous composition (dissolved nitrogen vs. oxygen), and flow regime (continuous
flow vs. episodic wetting/drying) on effluent chemistry. Results indicated
that the fluid composition (e.g., pH, redox, elemental composition) was
closely associated to dissolved and/or gaseous oxygen content and wetting
regime. Given these conditions, the use of a dry cover could reduce the
production of acid lechate over time, pending that it retards or eliminates
fluid and oxygen transport to the subsurface.
SREL Reprint #2756
Barton, C. D., L. Paddock, C. S. Romanek and J. C. Seaman. 2003. Geochemistry of an abandoned landfill containing coal combustion waste: implications for remediation. p. 105-141. In Chemistry of Trace Elements in Fly Ash, edited by K. S. Sajwan, A. K. Alva and R. F. Keefer. Kluwer Academic/Plenum Publishers.
