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rate exceed the rate of water entry into the well This indicated that recharge to the well was less than 14 gpm and the 24 hour constant rate test would need to be less than 14 gpm The 24 hour constant pump rate was set at 0 725 gpm During the constant pump test it was noted that both the A and B zones were effected, indicating that the clay separating the two zones is a leaky aqurtard Using Cooper and Jacobs straight line method the transmxssivity (T) for the A zone calculated to be 28 fl/ day The A zone is approximately 5 5 feet thick which would calculate hydraulic conductivity (K) at 5 1 ft / day Using the gradient information obtained prior to any pumping MW2 to MW6A on January 21, 2003 ("7 79 ft--7 87 ft/91 ft = 0 00087 ft/ft) and an effective porosity of 20% (silt/fine sand) calculates a groundwater velocity (v) of 022 ft/day or 8 03 ft/year ZONE B The Step Drawdown tests were performed on the two separate water bearing zones to determine at what rate to conduct the 24 hours Constant Pump Rate tests Well RW1B is screened across the B zone and the step drawdown test was initiated at a pump rate of 0 8 gallons per minute (gpm) and was increased in 0 5 increments At 5 0 gpm field data indicated that enough information was available to determine the pump rate for the 24 hours constant rate test The 24 hour constant pump rate was set at 4 11 gpm During the constant pump test it was noted that both the A and B zones were effected Drawdowns where first seen in piezometer PZ1B and then in piezometer PZ2B and piezometer PZIA and then at RW 1A After which vertical leakage became the dominant observation r� Again indicating that the clay separating the two zones is a leaky aqumtard Using Cooper and Jacobs straight line method the transmmssmvmty (T) for the B zone calculated to be 1317 ft2 / day The B zone is approximately 8 feet thick which would calculate hydraulic conductivity (K) at 16 4 ft/day Using the gradient information obtained prior to any pumping MW2 to MW613 on January 21, 2003 (-7 79 ft--7 88 ft/92 ft = 0 00097 ft/ft and an o } effective porosity of 30/o (fine - medium clean sand) calculates a groundwater velocity(v) of 0 055 ft/day or19 95 ft/year AQUA TARD BETWEENA AND B ZONE SANDS As discussed above, the 3-4 foot thick aquatard separating the A and B zone sands is considered a leaky aquitard Core investigations of this zone showed the clay to have abundant silty content and at piezometer PZ213 to also have very fine sand associated with it The constant drawdown test on RW1B suggests that this zone impends flows in some areas and in other areas does not form a significant barrier for vertical leakage RESULTS OF OVER-EXCAVATION OF GASOLINE CONTAMINATED SOILS As shown on Figures 4A, 4B and 4C the excavation of gasoline contaminated soils occurred in stages Using a 15 foot reach backhoe, the first stage of excavating occurred, removing relatively clean over-burden to the 10 foot depth Gasoline impacted soils in the upper 10 feet were associated with the southern most pump island and the former UST area Once the area was excavated to the 10 foot depth a ramp was constructed at the eastern edge of the excavation area to access areas that would need to be excavated deeper The area containing piezometers PZ2A and PZ213 was then excavated to the 14 9 Update Status March 2003