SITE INFORMATION AND CORRESPONDENCE_CASE 1

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Task 2.0 Quarterly Groundwater Monitoring Event We understand that existing monitoring wells are sampled on a quarterly basis for petroleum hydrocarbons, and water levels are measured to monitor the site hydraulic gradient. We propose to continue the quarterly monitoring effort with only minor modifications. Following the completion of SECOR's first sampling event, or the most recent event performed by others, we will briefly discuss the laboratory analysis findings with TVG. We anticipate that water samples collected from wells MW-2 and MW-5 will not contain detectable petroleum hydrocarbons. Assuming this to be true, in addition to the required Quarterly Monitoring Report, we will prepare and submit a request to PHS/EHD (on behalf of TVG) to reduce the monitoring requirements for these two wells. We believe there is currently sufficient data compiled for these two wells to reduce .the frequency of water sampling to an annual basis. After discussion with TVG, additional wells may be considered for reduced monitoring; however, our experience at similar sites indicates the PHS/EHD will consider the request seriously if they perceive the site's impacted area is "contained" by the remaining monitoring wells. Although no water sampling will be proposed at selected wells, it will be essential to continue to measure "pre-sampling" water levels in all wells within the network for the purposes of observing fluctuations in site water levels and groundwater gradients. The laboratory analytical methods to be performed will be limited to BTEX by Method 8020, and the TPH-g by modified Method 8015. In accordance with Tri Regional Guidelines, collected water samples will be submitted to a California certified laboratory for analysis, under chain of custody control. The budget proposed will include the preparation of one Quarterly Monitoring Report, and all costs and expenses required for the sampling and analysis of six monitoring wells. Although some cost savings will be realized from the reduction in the number of laboratory analyses performed,the more significant savings will obviously be derived from the elimination of labor and expenses required to conduct these activities. Task 3.0 Prepare the Final Remedial Plan As requested by PHS/EHD in their letter dated May 2, 1995, TVG is required to submit a CAP for the residual soil and groundwater impacted by petroleum hydrocarbons. The CAP requirement is fundamentally the same document referred to in the Tri Regional Guidelines as the Final Remedial Plan(FRP). The variation in nomenclature is related to which regulatory authority assumed the lead responsibility (County or State). Regardless, the Tri Regional Guidelines state that implementation of a FRP (or CAP) shall not begin without approval from both the County and the RWQCB. Ultimately, PHS/EHD will not recommend the closure of the Plant T site unless the responsible party has fully complied with the Tri Regional Guidelines on Site Closure (document dated January 1994). Tri Valley GrowersSECOR` N1130P.rpt 3 June 1,1995