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GROUND WATER MONITORING WELL INSTALLATION <br /> ' On 13 and 14 August 2002, five ground water monitoring wells were installed near the UST area <br /> (MW-1 though MW-5)to quantify the hydrocarbon concentration in ground water and determine the <br /> direction of ground water flow Field work was preformed as described in the AGE-prepared <br /> ' Monitoring Well Installation Work Plan,dated 08 July 2002, as amended and approved by the San <br /> Joaquin Country Environmental Health Department (EHD)by letter dated 18 July 2002 <br /> ' MW-1 through MW- were completed as ground water monitoring wells with slotted screen <br /> installed from approximately 15 to 35 feet bsg in borings MW-1 through MW-4 and from <br /> approximately 69 to 74 feet bsg in boring MW-5 Locations of the monitoring wells are illustrated <br /> ' on Figure 2 <br /> Results of the well installation and subsequent sampling delineated the dissolved hydrocarbons and <br /> ' indicated direction of ground water flow generally towards the northeast Ground water monitoring <br /> enabled delineation of the dissolved hydrocarbon plume The vertical assessment of the dissolved <br /> hydrocarbon plume Analytical data is presented on the attached tables <br /> 1 <br /> STRATIGRAPHY AND DEPTH TO GROUND WATER <br /> Silt, with a tan, brown or gray color, apparently depending on hydrocarbon impact, was generally <br /> encountered from a depth of approximately 5 feet to 35 feet bsg in the shallow well borings, the <br /> coarsest material was silty sand, collected at a depth of 25 feet bsg in boring MW-2 Silty sand was <br /> generally encountered to a depth approximately of 40 feet to 45 feet bsg Generally poorly graded <br /> ' sand and silty sand was encountered between 60 and 75 feet bsg in boring MW-5 Ground water was <br /> encountered at a depth of 30 feet bsg during drilling <br /> I <br /> 1 <br />