SITE INFORMATION AND CORRESPONDENCE

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• Mr. Eric Jenks 0 - 2 - 9 July 2003 The work plan is proposed to be implemented as described in GeoSyntec's 1 January 1999 Site Investigation Work Plan. As confirmed in a 3 July 2003 telephone message from Mr. Scott Felton of GeoSyntec, subsurface stratigraphy will be identified by continuous logs from two of the proposed borings, all groundwater samples will be analyzed for nitrate, ammonium, volatile organic compounds, chlorinated herbicides, fumigants (including 1,2,3 -TCP) and total petroleum hydrocarbons (TPH), and a report shall be prepared in about 15 weeks. In addition to the above analyses, the samples need to be tested for the carbamate urea pesticide group of constituents (EPA Method 8321), because bromacil is consistently detected in a downgradient on-site monitoring well. The on-site production well also needs to be analyzed for these constituents of concern and the results reported along with the results of the downgradient delineation. We concur with the work plan provided that JTF also incorporate the following: • add a grab groundwater sample near the northeast corner of the facility; • analyze the grab groundwater samples for carbamate urea pesticides; and sample the on-site production well for the constituents identified for the grab groundwater samples. JTF intends to schedule the work during the dry season, and the investigation report is due by 24 October 2003, which is about 15 weeks from now. The report should include a proposal for downgradient monitoring wells. Draft Monitoring and Reporting Program JTF has completed two years of quarterly monitoring and requests that staff revise the MRP to semi-annually in the second and fourth quarters, and remove organophosphate pesticides, atrazine, ammonium, and TPH as gasoline and diesel from the list of monitored constituents because these compounds are not consistently detected in the monitoring wells. The monitoring history at this site shows that periods of high groundwater are associated with the first quarter, although April and September have also had high groundwater occurrences. Therefore, semi-annual monitoring shall occur in the first and third quarters to coincide with high and low groundwater surface elevations, to the extent practicable. The existing network of monitoring wells surround the operations area of the facility. Many of the compounds that JTF requests be removed from the monitoring program are not detected in the monitoring wells, but were detected in grab groundwater samples obtained from the operations area. For this reason, organophosphate compounds, petroleum compounds and ammonium must continue to be monitored in wells MW -1, MW -4, and MW -5, which are downgradient of the operations area. Atrazine was detected in the only monitoring event in which it was analyzed. Therefore, the draft MRP includes analysis for the triazine compounds. TPH as gasoline is removed from the MRP