PCE concentrations appear to be trending lower in wells LS-1, LS-2, LS-3, LS-4, LS-6, RFR-10, RFR-11, and RFR-12, but PCE concentrations increased in OFR-3.

Well OFR-3 had PCE concentrations of 12.15 mg/L and TCE concentrations of 5.65 mg/L, both of which are above the MCL. These March 2002 levels are a sharp increase over previously collected data. CSSA immediately responded in accordance with the Plan by supplying bottled water and evaluating OFR-3 for a GAC filter treatment system. The GAC filtration treatment system was installed in April 2002. More information regarding GAC confirmation samples at OFR-3 will be submitted in the next quarterly report.

In January 2001, well LS-2 had PCE concentrations of 4.82 mg/L and TCE concentrations of 0.2 mg/L. PCE concentrations were approaching the MCL (5.0 mg/L) and TCE concentrations were reported below the RL. CSSA had been engineering and designing a GAC system in accordance with the Plan for LS-2 and LS-3. The GAC filtration treatment system was installed during the week of April 1, 2002, to provide filtration for wells LS-2 and LS-3. Additional information on the LS-2/LS-3 GAC system will be submitted in the next quarterly report.

All objectives listed in Table 1-1, Sampling Rationale for March 2002 were accomplished. All wells were able to be sampled for the March event.

Wells DOM-2, FO-J1, HS-2, I10-4, JW-14, JW-26, LS-1, LS-4, LS-5, OFR-1, OFR-2, and RFR-12 had low concentrations of PCE, TCE, chloroform and/or 1,2-DCA above the MDL, but below the RL and less than 90 percent of the laboratory MCL. Based on the Plan these wells should be retained for future quarterly sampling events, including the June 2002 quarterly sampling event.

Wells FO-8, FO-17, I10-7, and JW-9 had detections of methylene chloride above the MDL but below the RL. Well I10-7 also had a detection of toluene above the MDL, but below the RL. Well I10-2 did not have any VOC concentrations detected above the MDL. Due to the apparent laboratory contamination associated with methylene chloride, it will be considered for removal from the analyte list in the future.

Wells OFR-3, RFR-10, RFR-11, LS-2, LS-3, LS-6, and LS-7 groundwater will continue to be sampled and monitored on a quarterly basis until they meet DQO requirements of four consecutive quarterly events with no detection of contaminants. Dependent upon regulatory agencies� concurrence, the sampling frequency may then be reduced.