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!} rya 1 y hthology from grade to 75 feet bgs consists of varying degrees of sandy silt and silty sand grading at depth to poorly graded course grained sand and gravelly sand, with interbedded silt layers throughout The boring logs from SB-1 and SB-2 (Attachment 3) indicate several intervals of poor recovery, due mostly to refusal in the shoe of the 5-foot core barrel when larger gravels were encountered Analytical Results All available soil and groundwater analytical data for samples collected at the four GeoprobeTM and two continuous core borings are presented as Attachment 4 Tables 2 and 3 (Attachment 2) summarize histoncal soil and groundwater data, respectively In addition, hydrocarbon impacted soils were observed in PID readings from the GeoprobeTm and continuous borings to a depth of approximately 30 feet bgs, then dropping off as groundwater was encountered as shown on the boring logs (Attachment 3) No hydrocarbon impacted soils were observed in the core from SB-1 or SB-2 at depths below where first water was encountered PROPOSED ADDITIONAL WORK Monitoring Well Installation The screen intervals for the six proposed wells are presented as Table 1, Attachment 4 The screened intervals were selected based on information obtained from boring logs of the GeoprobeTm and continuous core borings Due to the proximity to the proposed well locations, boring logs for GP-4, SB-1, and SB-2 were used and are included as Attachment 3 Minor changes have taken place in the spotting of the wells since the April 25, 2000 work plan, based on accessibility and utility clearance problems identified in the field As shown on the attached Site Plan (Figure 2, Attachment 1), MW-7 and MW-9 have been shifted approximately 20 feet to the east and 40 feet to the south, respectively The placement of all six wells should provide the information needed to adequately assess site conditions File R Wetinsl ltr