Bedrock below the Site ranges from approximately 25 to 120 feet below ground surface (bgs). The bedrock is
karstic. Karst bedrock is characterized as irregular limestone in which erosion has produced fissures, sinkholes,
underground streams and caverns. Weathered features, discovered during the site characterization, are assumed to be pathways for TCE contamination to enter the aquifer. The bedrock is overlain by dense red clay with chert dispersed throughout.
The depth to groundwater varies across the site from 250 feet bgs on the northern portions of the FAG property to
emerging at the surface through springs and seeps in the Thurman and Shoal Creek bottoms.
Targeted Environmental Media:
 Fractured Bedrock
Vertical contamination has reached the underlying limestone aquifer and lateral contamination is reported to be at least 2 miles south of the facility.
Major Contaminants and Maximum Concentrations:
- Trichloroethene (510*)
- 1,2-Dichloroethene (Not given)
- Vinyl chloride (Not given)
No technologies selected.
- Other (Monitored Natural Attenuation in overburden and shallow bedrock)
Comments:
MNA, through hydrodynamic dispersion, is the primary in-situ natural attenuation process throughout the Mississippian Aquifer.
MCLs were chosen for the cleanup goals.
*510 ug/L is an offsite residental well. TCE in groundwater at the bedrock overburden interface has been as high as 10,000 ug/L.
Monitoring of groundwater to support MNA is occurring.
http://cfpub.epa.gov/supercpad/cursites/csitinfo.cfm?id=0702514
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