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hF� KLEINFELDER petroleum hydrocarbons were not found in MW-2. It appears that the eastern "zero-line" of the plume lies somewhere near, but to the west of MW-2. The southern, western, and northern extent of the plume cannot be defined from the existing data. Based on the conclusions outlined above, the following recommendation/workplan was also detailed in our April 13, 1994 report: We recommended driven Geoprobes similar to those performed during implementation of the current workplan, but accompanied by a mobile laboratory to provide real-time data for location of probes during fieldwork. Initially, or an estimated six Geoprobes (one day) will be performed focusing on portions of the site north, west, and south of the formerly- repaired pipeline away from MW-2, GP-7 and GP-8 where very low to non-detect concentrations of diesel-range hydrocarbons were encountered in groundwater. Each of these six Geoprobes will not only be sampled for groundwater but soil samples will be collected at depths of 2, 5, and 10 feet above the equilibriated groundwater surface rather than first encountered groundwater and will be analyzed for moisture content to assess the thickness of the capillary fringe. Groundwater samples should be analyzed by a State Certified mobile laboratory onsite and the location of Geoprobes to be performed on the second day will be based upon the results from the first day results. Another six Geoprobes to complete characterization on the second day may be necessary. Groundwater samples should analyzed only for diesel-range hydrocarbons by the onsite mobile laboratory since previous Geoprobe and monitoring well samples analyses identified very low to non-detect concentrations of gasoline-range hydrocarbons and/or BTEX despite otherwise high concentrations of diesel hydrocarbons. Soil samples will be similarly analyzed at a State Certified stationary laboratory. On May 27, 1994, a letter was sent to Leprino Foods from Ms. Wendy L. Cohen of the Central Valley Office of the State of California Regional Water Quality Control Board. Attached to the letter was a draft Clean up and Abatement Order. Those documents requested a formal workplan and time schedule for a third phase of the groundwater assessment and results of samples collected from the oil/water separator among several items. The workplan and time schedule for the proposed Phase 3 Groundwater Assessment is outlined in this document. �I 24-220176-FO1/CR43-8 (1994) Page 6 of 13 June 3, 1994 Copyright 1994 Kleinfelder, Inc.