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r Working To Restore Nature Laboratory analyses of groundwater samples (Table 2) detected gasoline constituents above laboratory method detection limits in groundwater samples collected from each site monitoring well Initial groundwater monitoring data (March, 1992)determined groundwater flow direction was to the south. Groundwater monitoring conducted during November 1992 indicated a northerly groundwater flow direction beneath the site Groundwater measurements collected in December 1992, February 1993, May 1993, and June 1993 indicated the groundwater gradient direction had shifted to the southwest. The measured groundwater gradients for the May and June 1993 are depicted on Figures 2 and 3, respectively Floating free product has been observed in well MW2 during fluid level monitoring events in November and December 1992, as well as May and June 1993 However, no free product was observed during the February 1993 monitoring event. Pursuant to PHS/EHD correspondence dated June 11, 1992, the unused onsite well was investigated A video log of the well was produced by Water Well Technology, Inc , on July 16, 1992 Supervision of logging activities was provided by Delta Pump Company personnel. The video log revealed that the 8-inch diameter well was cased to a depth of approximately 102 feet below grade The total depth of the well was approximately 155 feet below grade No casing flaws were evident from the video log The facility well was subsequently destroyed in accordance with State and PHSIEHD guidelines In correspondence dated June 1, 1993, the PHSIEHD requested additional work be performed to further define the extent of documented soil and groundwater contamination at the site PROPOSED SUBSURFACE ASSESSMENT WORKPLAN RESNA proposes a total of eight soil borings be advanced at the site to further characterize subsurface conditions underlying the site Four soil borings will be drilled in the vicinity of the former tank pit to delineate residual soil contamination Four additional soil borings, which will be converted to groundwater monitoring wells, will be placed outward from the existing building to further define the lateral extent of groundwater contamination Proposed bonng/we111ocations are shown on Figure 2. Installation of Soil Borings/Monitoring Wells i Drilling will be conducted using a hollow stem auger drill ng equipped with eight-inch outside diameter continuous flight augers Borings will be advanced to approximately 15 feet below grade, the depth of saturation Four soil borings will be completed as two-inch diameter groundwater monitoring wells by further advancing the boring to approximately 30 feet below grade (fifteen feet below the water table) Actual completion depths will be determined in the field based on hydrogeologic conditions encountered All procedures and protocol for groundwater monitoring well construction will conform to the standards for the construction of groundwater monitoring wells presenter) in the State Water Resources Control Board Leaking 0W05961REP0RTSIWPA-443 FNL