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I <br /> 12 December ecember 2001 <br /> AGE-NC Project No 98-0452 <br /> Page 2 of 4 <br /> The purpose of this investigation was to locate a source for the recurring concentrations of MTBE <br /> in ground water samples collected during quarterly monitoring activities <br /> 2 1 GROUND WATER DEPTH AND FLOW DIRECTION <br /> The depth to ground water was at approximately 4 feet bsg during the November 2001 site <br /> investigation During the seven ground water monitoring events, ground water flow direction has <br /> varied from the east-northeast to the south-southwest It appears that ground water flow at the site <br />' is influenced by seasonal hydrogeologic changes <br />' 3.0. PROCEDURES <br /> On 10 October 2001, four soil probe borings (P-1 through P-4) were advanced at the site as part of <br /> the site assessment related to former USTs The field work was conducted as outlined in the AGE- <br /> prepared,Additional Site Assessment Work Plan, dated 25 July 2001 <br />� s <br /> 3 1 GRAB GROUND WATER SAMPLING ACTIVITIES <br /> Probe borings P-1 through P-4 were advanced utilizing a truck-mounted Geoprobe 5400 equipped <br /> with 1 125-inch diameter probe rods using"direct push"technology Probe borings P-1 through P-4 <br /> were advanced vertically to a depth of 15 feet bsg for collection of grab ground water samples <br /> 3 1 1 Ground Water Sample Collection <br /> A grab ground water sample was collected from each probe boring using a temporary PVC screen <br /> The probe rods were advanced to a depth approximately four feet below the water table The hollow <br /> steel rods were then removed, and a screened casing was inserted into the saturated zone Ground <br /> I water was allowed to enter the casing, and samples were retrieved using a modified PVC tubing <br /> bailer Sufficient sample was collected to fill three 40-m1 EPA-approved VOA vials containing 0 5 <br /> ml 18% hydrochloric acid as a preservative Ground water sample containers were labeled with <br /> probe boring designation, date, time, and samplers initials and then placed in a chilled container <br /> 3 1 2 Equipment Decontamination <br /> Geoprobe rods were thoroughly cleaned prior to soil probe boring advancement <br /> Advanced GeoEnvironmental,Inc <br />