See POLREPs #4 and #5 for Site description information.
Water levels in the basement and vault areas rose above levels within these areas observed by EPA in August. This observation indicates that precipitation and/or underground waters are entering these features. Since these features are not decontaminated, the waters entering these features may likely become contaminated.
Analytical information collected in August 2008 indicate that high concentrations of PCB contamination remain within the sediment and debris within the on-Site drainage systems. Analytical data indicate, among other things: 3911 mg/kg in the sediment within the westside drainage system, 335 mg/kg within the sediment removed from the storm sewer along Bluefield Avenue, and 65 mg/kg within the sediment of the sump in Area 3b. Each of these features is connected to the area storm water system which drains to area surface waters.
Preliminary analytical results of soils collected beneath the concrete slab in certain areas of the Site do not suggest elevated PCB contamination.
Preliminary analytical results of water samples collected in August 2008 also suggest that elevated PCB contamination is found in the storm waters (surface water stream Whitley Branch which runs through underground culverts in Bluefield) and the highest concentrations are at and downstream of the Site. Significant data problems, however, render much of the surface water data unsupportable. Nonetheless, levels as high as 16 ug/L were detected in storm waters near the Site.
Removal activities were re-mobilized October 13th to conduct disposal of the wastes generated during the Removal Activities conducted in August and collect additional samples.
The ERRS pumped the majority of the water stored in the temporary tanks (originally to allow for inmplementation of the removal action) back into the features from which it came. The known exit points from these features had been plugged during the removal action. The OSC arranged for off-Site transportation and off-Site disposal of some of the water such that an excessive amount of water did not need to be pumped into the on-Site features and the difficulties (if any) associated with off-Site disposal of the water could be evaluated.
Additionally, some of the water was pumped from the temporary tanks slowly through a treatment system to determine if the water could be treated to a point where it could be safely discharged into the local sewer system. Samples were collected and sent for PCB analysis. Originally, the water in the basement and compressor room contained 3.6 and 7.4 ug/L of PCBs, respectively. After running through carbon, the levels were reduced to 0.17 and 0.03 ug/L, respectively. The standard for local discharge may be 0.0017 ug/L.
The drummed wastes were transported and disposed from the Site.
Debris, including personnel protection clothing and other debris generated during the action (e.g., hoses) was transported and disposed from the Site.
Due to significant problems associated with the sampling of surface water and other media, the OSC arranged for re-sampling of surface waters and specific on-Site soil/sediments for PCBs. The previous sample labelling was conducted in a way that some sample results could not be matched to some sample locations. Both a baseflow and rain event sampling event was conducted.
The temporary mechanical plug placed into the old sanitary system through the manhole located in former Area 4 (High Voltage) was evaluated. A small amount of water had backed up behind the plug, but not so much as to suggest that the origins of the water were from multiple upstream sources and not from local ground water infiltrating into the pipe. The OSC collected a sample of the sediment in the manhole and will await sample results before a final decision regarding this feaure is made.
All other plugs also appeared to be working as water levels in the features rose above August levels.
The response action is currently demobilized until EPA completes discussions with parties potentially responsible for the Site and further evaluates outstanding analytical information and next steps.
Evaluate treatment and discharge of waters from the Site, further containment, or disposal of the waters at the Site.
Evaluate whether the plug in the old sanitary system can be made permanent.
Evaluate and plan future actions including disposal of debris, removal of high concentration PCB sources (e.g., sediment in on-Site drains, transformers, etc.), further characterization of extent of contamination on-Site and off-Site in drainage systems. Also, evaluate whether these actions can be conducted by other parties (e.g., past or present owners or operators of the facility) or the EPA.
Continue evaluation and planning of next removal actions and discussions with parties potentially responsible for the Site.
Await finalization of analytical data.
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