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TECHNICAL APPROACH The technical approach to this project will be to perform the following work tasks: • Perform a document review of the PHS-EHD file for this site and nearby sites. • Perform a 2,000-foot radius well survey to ascertain proximity of registered wells to the site. • Review the on-site well log and construction details to ascertain sanitary seal depth and sample the well. • Perform a reconnaissance, preliminary site vertical and horizontal subsurface investigation to collect soil and groundwater samples in the former tank pit areas and in the assumed groundwater downgradient flow direction(to the uppermost aquifer and top of the underlying aquitard). • Prepare a site preliminary site investigation report. WORKPLAN State Fund Application Wright will assist property owner with application to the Fund for reimbursement of clean up costs, consistent with Fund requirements. Well Survey Wright will conduct a well survey of available regulatory (State, County, City databases or files) for known registered well locations. In addition, review databases for listed sites within %z mile and review readily available records within 2000 feet which may contain well location information. The survey will present the results of those file searches; please note that agency files may contain incompletely filled logs or forms depending upon the completeness of the water well drillers forms at the time of those forms' preparation. On-site Well Samplin¢ The on-site water well will be sampled using the existing pumping equipment in the well. Depth to groundwater measurements will be attempted in the sounding port and measured to the nearest one-one hundredth of one foot. The well will be purged to clear the lines and draw aquifer water. As the purge volume is removed,a measurement of pH,electrical conductivity and temperature will be recorded prior to sampling. The sample will be carefully collected and poured into the appropriate laboratory prepared containers with minimum cavitation. The water sample will be labeled, logged onto a chain-of-custody form, and placed in a chilled ice chest on crushed ice. Wright will request a copy of the well log and construciton detail from the owner. Exploratory Borings Up to six exploratory borings will be drilled at the site (Figure 2). Drilling and well installation permits will be secured from PHS-EHD, and all utilities will be cleared prior to doing the fieldwork. The exploratory boreholes will be positioned in the former tank pits, and in the assumed downgradient flow directions as shown on Figure 1. The boreholes will be advanced to locate the capillary fringe vicinity, upper contact of the uppermost water bearing strata (aquifer) and continued to the lower contact of the aquifer(upper contact of the aquitard)J Borehole total depths are estimated to be about 20-25-feet deep for this study, however, the boreholes will be advanced to the upper aquitard contact. The boreholes are positioned to assess contaminant presence in the former tank pits and potential downgradient extent of contaminant movement from the two tank sources. The boreholes for this reconnaissance assessment will be drilled with truck mounted direct push drilling equipment. It is anticipated that a GeoProbe rig will be used to collect soil and groundwater samples since the site has limited access within the low ceiling storage canopy. The Geoprobe can push soil sample collection tools to discrete depths as desired.