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borings beneath the existing service station building, as illustrated in Figure 2 They were drilled at an angle of 20° from vertical, and bottomed approximately 10 feet from the surface location (Figure 3) Borings JLM-7, JLM-8, JLM-9, and JLM-10 were drilled with the Geoprobe®, and soil samples were collected continuously from the surface to the bottom of each boring The samples were collected in a clear plastic sample tube, and were examined by a geologist for evidence of petroleum contamination as well as lithologic information The tubes were sawed at selected intervals and short lengths of the core were screened for organic vapors with a portable photo-ionization detector (PID) and then covered with plastic end caps and preserved in an ice chest for later transport to the analytical laboratory The remainder of the sample tube was then described on the boring log (Appendix A) Drilling was terminated when the borings reached the water table The drill rods were removed and a string of 1-inch diameter PVC pipe was lowered to the bottom of the boring The lower portion of the pipe was slotted to allow water to enter The driller then inserted plastic tubing through the PVC to collect a water sample In all four borings, water was encountered at a vertical depth of between 26 and 28 feet JLM-8, JLM-9 and JLM-10 produced sufficient water to fill three 40-m1 glass vials and a 1-liter amber bottle, but JLM-7 yielded only enough water to fill two or three vials The samples were preserved in the ice chest Borings JLM-6 and JLM-11 were drilled by the BK-81 rig, and samples were collected at . 5-foot intervals beginning at a depth of 10 feet The samples were screened for hydrocarbon odors and described on the boring log, aria selected samples were preserved for laboratory analysis When groundwater was encountered at approximately 25 feet, both borings were advanced an additional foot and a disposable plastic bailer was lowered through the augers to collect a water sample A liter bottle and three 40-m1 vials were collected from each boring Both borings were then advanced to the base of the aquifer, which was known from previous drilling and the original excavation to be at a depth of 40 feet In JLM-11, samples were collected at 5-foot intervals, but no additional soil samples were collected from JLM-6 When these borings reached a depth of 35 feet, a Simulprobe® sampling device was attached and inserted through the augers to collect a discrete water sample at the target depth of 3 6-3 8 feet,dust above the base of the first aquifer The samples were handled in the same manner as those collected at the water table The purpose of these samples was to determine whether groundwater contamination extended to the base of the first aquifer, as requested by CVRWQCB After all borings had been sampled, they were backfilled by pumping cement-bentonite grout through a tremmie pipe Drill cuttings were stored in 55-gallon drums behind the station building Eighteen soil samples and eight water samples were shipped to McCarnpbell Analytical Laboratory in Pacheco, where they were analyzed by EPA methods 8015m for Total 4