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l � UNLARmplax Tech Alensojor CImm,.rru,;a, wStsuas Sail sme wo,;12016 4.2.2. PCB Ground Water Sample Results Because PCBs were detected in some subsurface soil samples in me Eastern GSA debris burial [reach area, DOE LLNL collected grand water samples for PCB analysis boom wells located near and/or downipment farm the boreholes in which the PCBs were detected. Ground water samples collected from wells W-26R-01, -03, -04, -05, -07, and -11, and W-25NA1 and - 24 were analyzed for PCBs using EPA Method 8082A (Figure 16). '1 he PCB analytical results Bar around water samples collected from these wells am presented in Table 5. An attempt to sample well W-26R-05 on December 3, 2014 was unsuccessful due m insufficient water. In addition, ground water samples were collected tram well W-7P, located N the vicinity of the Central GSA debris burial trench 113 and analyzed for PCBs to determine if PCBs may have been released to ground water hum this Cement GSA debris burial [rencb. Because debris burial rench 03 and nearby well W-21) are not located in the Faster GSA debris burial trench area and therefore arc not relevant to the forum GSA debris burial bench characterization summarized in the Tech Memo, well W-'IP is not shown on Figure 16. Analytical results indicate that PCBs were not detected in any of the ground water samples above the 0.5 µg/L reporting limit, including the sample collected from Central GSA well W-V. 5, Data Evaluation Analytical data obtained for the subsurface sail samples collected in the debris burial bench am werse evaluated fin SVOC, PA I, and PCB concentrations according to the data evaluation process outlined in the "Cbaructerizatiou Work Plan Or SubamGce Soil in the Easter General Services Area Debris Burial Trenches;' and agreed to with the regulatory agencies. In the Work Plan, a series of hhhen scenarios were presented by which the soil data would be evaluated to determine the next sups to be taken. This section presents those Work Plan scenarios with a discussion of due data evaluation that was conducted based on the actual data collected. The if%then scenarios specified and agreed to in the Work Plan included: I. The results of the subsurface mil sampling in the Easter GSA debris burial trench seem to be considered as sufficient evidence that there is no risk to human health or threat to ground water associated with these constituents if: • SVOCs, PAIIs, and PCBs am not detected at concentrations above the analytical reporting limit in any subsurface soil sample. • The samples include soil collected near mewl debris encountered in the boreholes. Therefore, the investigation of the Eastern GSA Debris Burial Trenches is considered completed and no further action (i.e., additional soil sampling) for these constituents is realest. Dula Evaluallon: No SVOCs or PAHs were detected in subsurface soil samples at commutations above their respective analytical method RL,, therefore no further evaluation ofthese constituents was conducted. PCBs detected at concentrations above the analytical method RL did not exceed their respective regulatory screening levels.