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drawdown of 0 15 feet and is located 168 feet from RW-1A Well MW-2, located 122 feet from RW-IA had a maximum observed drawdown of 0 12 feet during the constant-discharge test Ground water samples collected at the beginning of the step-discharge test and at the end of the constant-discharge test were analyzed for TPPH, BTEX, and MTBE A total of approximately 7,600 gallons of water was pumped from RW-IA during the step-discharge and constant-discharge tests The results of this analysis are presented in Table 5 and summarized below At the start of the step-discharge test TPPH was detected at a concentration of 120,000 ppb, benzene at 11,000 ppb, and MTBE at 310,000 ppb At the conclusion of the constant-discharge test TPPH was detected at 56,000 ppb, benzene at 6,100 ppb, and MTBE at 220,000 ppb Well MW-2 During the constant-discharge test performed in Well MW-2 the pumping rate was maintained at 1 5 gpm for 360 minutes (6 hours) This flow rate produced a drawdown in MW-2 of approximately 2 feet within 30 minutes of pumping Drawdown steadily increased during the test and reached a maximum drawdown of 3 7 feet below static water level The closest observation well, MW-7, is located 63 feet from the pumping well (MW-2) and did not show any discernible drawdown as a result of pumping from MW-2 Wells MW-5 and MW-8, located 99 and 110 feet, respectively, from MW-2 showed negligible drawdown during the constant-discharge test in MW-2 Analysis Water level recovery data was collected from the pumping wells (RW-IA and MW-2) after the pump was shut off in each test The recovery data was used to approximate the aquifer's transmissivity using the Jacob straight line method The recovery data for each well is shown in graphical format on Plates 4 and 5 The transmissivity value calculated for RW-IA was 447 gallons per day per foot (gpd/ft) or 64 square feet per day (ft2/day) The hydraulic conductivity (K) value was calculated by dividing the transmissivity by the aquifer thickness The aquifer was assumed to be approximately 10 feet thick which yields a K value of 6 4 feet per day (ft/day) or 2 3 x 10.3 centimeters per second (cm/s) This value of K is typical of a silty sand aquifer, which is the predominant soil type found in the saturated zone at this site The transmissivity value calculated for MW-2 was 325 gpd/ft or 43 6 ftz/day Assuming an aquifer thickness of 7 5 feet in the vicinity of MW-2, the K value was calculated to be 5 8 May or 2 1 x 10-3 cm/s As with RW-1 A, this K value is consistent with the properties of a silty sand aquifer as has been found beneath the subject site 240-0783 9