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underground fuel storage tank at the Sebastiani Lodi facility and to provide data necessary for development of a remedial action plan for soil and groundwater cleanup, as requested by the SJLHD and the California ip Regional Water Quality Control Board (RWQCB) i The initial approach taken to achieve this was to Drill three soil borings around the former tank site and take pre-construction, groundwater quality screening samples from the auger flights at each boring These groundwater grab samples were analyzed for total petroleum hydrocarbons as gasoline (TPH- G) and for aromatic volatile organics (VOAs) , • If significant contamination was detected in groundwater screening samples, the borings would be completed as four inch diameter monitoring wells which may be appropriate for groundwater extraction If significant contamination was not detected in groundwater screening samples, borings would be completed as two inch diameter monitoring wells , • Take soil samples from each boring at a minimum of five-foot intervals, and analyze two samples from each boring for TrH-G by Modified EPA Method 8015 and for VOAs by EPA Method 8020, • Develop, allow for equilibration, measure depth to water level, survey top of casing elevations, and sample all monitoring wells for TPH-G by Modified EPA Method 8015 and VOAs by EPA Method 602, upon completion of each individual well, • Based on results of VOC analysis of groundwater samples, sample selected wells for ethylene dibromide and organic lead content, • Drill, construct, and sample an additional seven groundwater monitoring wells, based on water quality data and direction of groundwater movement as derived from the first three wells These additional wells were located laterally and downgradient of the first set of wells to further assess the extent of groundwater contamination • Define to the extent possible, the limits of soil contamination in the area surrounding the former tank site This was accomplished by analyzing selected soil samples collected from . six of the monitor well borings for TPH-G and VOAs and drilling an additional five shallow soil borings directly adjacent to the tank excavation site (SB-1 through SB-5) Soil borings SB-1, - 2, and -3 were drilled approximately 15 feet from the edge of the "inner excavation" (Figure 3) Soil borings SB-4 and -5 were drilled approximately 25 feet from the edge of the inner excavation One soil sample from each boring was analyzed for TPH-G and VOAs 8