Monday, October 17, 2011

Latest Cleanup Plan for Texarkana Site May Stick

By: Duane Craig

The latest Environmental Protection Agency record of decision on the Texarkana Wood Preserving Site modifies the earlier RODs from 1993, 1998 and 2010. The ROD outlines the processes that are used to cleanup the list of environmental issues at a Superfund site.

The new remediation plan is to solidify the creosote contamination in the soil right where it lies. Contaminated soils will be removed to a depth of two feet and then consolidated on-site. Deep groundwater contamination will continue to be monitored to see if and when it migrates toward sensitive areas. The shallow groundwater contamination had not been addressed in earlier decisions, other than to monitor to make sure it didn’t move into nearby Day Creek. But now, that shallow contamination will be monitored for natural attenuation where the materials break down over time and are then absorbed by naturally occurring processes.

The main contaminants at the site are polynuclear aromatic hydrocarbons, or PAHs, and pentachlorophenol, or PCP. There was an estimated 88,920 cubic yards of soil and sludge “contaminated with PAHs, PCP, and dioxin … and 460,000 gallons of dense non-aqueous phase liquid, or DNAPL, and 49,000,000 gallons of contaminated groundwater. The primary contaminant risk is benzo(a)pyrene.”

Originally the plan was to incinerate the wastes, but the public wouldn’t go for that. So there were a series of RODs proposed and then changed as new information came to light. Previously, the EPA and Texas had completed removals and stabilizations of the contaminates and structures and had fenced the property to keep people from harm.

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