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On 18 September 1990 a preliminary pump test was conducted in well RW 1 to establish a sus- tainable pumping rate for this well. The test lasted about 12 hours and determined that a pump- ing rate of 3 6 gpm should be used for the actual pump test. Wells RW2 and RW3 were moni- tored during the preliminary test, but no significant drawdown (more than 0 01 feet) was ob- served The total drawdown observed in well RW 1 during this initial test was 6.26 feet. On 19 September, a long-term pumping test was conducted in well RW 1: water was pumped from the well to a temporary storage tank with a submersible pump. The test was started at 0804 hours, after all monitoring wells were gauged, and lasted 11 hours During the first nine hours of the test a pumping rate of 3 7 gpm was maintained; after that, because drawdown was significant and did not stabilize, the pumping rate was reduced to 2 7 gpm The test was completed at 1905 ihours Water table recovery measurements were continually recorded for two hours after the pumping was stopped. During this pumping/recovery test, depths to water in three wells (RWI, ' RW2, and RW3) were monitored using two HERMIT SE 1000B electronic data loggers and three pressure transducers These wells, along with wells MWI and MWS, were periodically double-checked using a Solinst water level indicator or oil/water interface probe The flow rate was monitored with an Omega turbine totalizer calibrated to 0 1 gallons Water was discharged into a 10,000-gallon Baker tank, and after testing it was disposed of in the sanitary sewer On 20 September a two-hour pumping test was conducted on well RW2 This well was pumped at the rate of 2 4 gpm, and induced drawdown was monitored in wells RW 1 and RW3. Pump Test Analysis ' To determine the hydraulic properties of the aquifer, recovery data from well RW 1 and draw- down data from well RW3 (while RW1 was pumped) were used Data from well RW2 were not used, because the water level fluctuated, and the total observed drawdown of 0.03 feet may not reflect a real aquifer response to the pumping of RW 1 Recovery data from RW3 were also not used because a 1-foot thickness of LPH the water table apparently affected its return to initial level. the water table there did not move up during the first two hours after pumping was stopped, and it was still about 0 1 feet below the initial static level 20 hours after the test was concluded Because the aquifer thickness is unknown, for interpretation purposes it was assumed to be 20 feet thick, based on well logs RW 1, RW2, and RW3 The aquifer was assumed to be homogene- ous and unconfined, without horizontal boundaries The results of the tests are summarized in Table 3 The values differ from well to well, reflecting either the heterogeneous nature of the alluvial sediments underlying the site or the "well skin" effect that developed during well drilling and development. Theis's equation was used to estimate the radius of influence• R = 1 5(Tt/S)°5 (De Marsily, 1986) ca�.gn3vau�si� 6