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monitoring wells were gauged,and lasted 11 hours. During the first 9 hours of the test,a pump- ing rate of 3.7 gpm was maintained;after that because gdrawdown ile dest Was completed significant and did not stabilize, the pumping rate was reduced to 2.7 gpm. Water table recovery measurements were continually recorded for�'_hours after the pumping was stopped. During this pumping/recovery test,depths to water in three wells tWIltrce pressure RW3) were monitored using two HERMIT SB 1000) electronic data loggers a transducers. These wells,along with wells MWI. and MW 8,were periodically double-checxcd 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 gallon. Water was discharged into a 10,000- gallon Baker tank and later disposed of into the sanitary sewer. On 20 September 1990 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. Also on 20 September,an injection test was conducted in well MW7, in order to properly size an injection trench or to establish that a series of injection wells located along die western property line would be sufficient to generate a hydrogeologic mound or barrier,to prevent hydrocarbons from an upgradient source(identified in MW$from being pulled under the site). Tap water was injected into well MW7 at the rate of 7.5 gpm for 155 minutes (2-112 hours). Water level meas- urements were recorded every 15 minutes during the test. The results of well gauging in MW I (drawdown vs. time) were used to determine transmissivity of the saturated and unsaturated zones under the site. The computer program WHIP(Welt Hydraulic Interpretation Program; Hydro Geo Chem., inc. $)was used to interpret the data from both pumping and injection tests. This program uses 198 the 8)wa Cooper method for initial estimation of transmissivity and storativity; these values are then refined by iterative automatic parameter estimations(IPE). In the IPI:,mean aqui.or param- n of Newton's nonlinear iterative eters are refined by using the Levenberg-Marquardt versio optimization algorithm. Values of transmissivity estimated in this manner ranged from 150 (RW2)to 300 fO/day(RW3)(Table S). 5 c6y.a4I137�T11^91M