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feet below grade in the bore hole, indicating that the water is <br /> confined The static water level appears to be at a depth of 37 feet <br /> below grade The thickness of the water-bearing layer appears to <br /> vary from less than 1 foot to more than 10 feet in the vicinity of the <br /> excavation <br /> Six of the bonngs were converted to 4-inch-diameter monitoring wells <br /> (Figure 1-2) Elevations of the well casings for wells MPW-1, MPW-2 <br /> and MPW-3 were surveyed in the field using benchmarks of known <br />' elevation Subsequent measurement of depth to groundwater in the <br /> three surveyed wells showed a northerly groundwater gradient with <br /> a slope of 1 foot per 1000 feet (0 00 1) <br /> MPW-1, MPW-2, and MPW-3 were developed and sampled <br /> November 19, 1990 Well recharge rates were estimated during <br />' development and appear below <br /> • MPW-1 20 gallons per hour <br /> MPW-2 60 gallons per hour <br /> • MPW-3 20 gallons per hour <br /> 1 <br /> f Sail hn <br /> Analytical results of all soil samples are shown in Table <br /> samples were taken in all of the borings except MP-9, MP17 , MPs 91 <br /> and MP-22 through MP-25 (These borings were installed to obtain <br /> groundwater samples with a hydropunch ) <br />' Results of soil analyses from borings MP-1 though MP-8, installed <br /> during No,,ember, show diesel and gasoline contamination in <br /> varying degrees on the west side and around the eastern perimeter of <br /> the excavation (Figure 3-3) Although no soil samples were taken <br /> from boring MP-9 on the north side of the excavation, diesel and <br /> gasoline odors were noted in this boring The highest concentration <br /> of diesel was found in boring M13-2 at a depth of 40 5 feet Gasoline <br /> was also found at the highest concentrations in this area This <br /> correlates with the October findings of diesel at a depth of 33 feet at <br /> slot 6 <br />' Diesel and gasoline contamination <br /> depthsof 41 to 46feet below <br /> in <br /> substantial concentrations at d <br /> p grade in <br /> boring MP-7 These samples were not submitted for laboratory <br /> analysis since contamination was evident It should be noted that <br /> previous sampling of slot 3 encountered very little contaminated soil <br />' at a depth of 33-35 feet below grade <br />' 3-2 <br />