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Figures 3-4 and 3-5 show the semi-logarithmic plots of drawdown versus time analyzed by the Cooper-Jacob method. These graphs correspond to the aquifer tests conducted by pumping wells MW-DIS-81)and MW-DIS-8S. For discharge, Q, measured in gallons per minute (gpm), transmissivity,T, in gallons per day per foot (gpd/ft) is calculated with the equation: 264 _ Q 1 T Ss where Ss is the drawdown over one log cycle on the time scale. Applying this analysis to the data from MW-DIS-8S yields a transmissivity of 25.6 fe/day. The hydraulic conductivity for the shallow aquifer is 1.28 ft/day, assuming a well screen interval of 20 feet. Storativity could not be calculated because there was no significant drawdown in any of the observation wells. The Cooper-Jacob analysis was also applied to the data from the MW-DIS-8D pumping test.. This analysis reveals a lower transmissivity for the B-Zone aquifer. The estimated transmissivity is 11.3 ftZ/day, and the hydraulic conductivity is 1.33 ft/day, a screen length of 10 feet. Again, storativity of the aquifer was not estimated because there was no observable drawdown in the observation wells. Leaky Aquifer Analysis ( Pump test data were also analyzed using the Hantush method for evaluating leaky semi- confined aquifers. The response of the pumped wells and the historical water level changes indicate that a leaky aquifer model may be appropriate. These models are based on the assumption that the pumped aquifer is bounded either above or below by a semi-permeable bed that permits water to flow vertically into the pumped aquifer. i F' Water level responses in wells located in the pumped zone may be analyzed with either the Hantush r/B solution (Hantush, 1956) or the Hantush B solution (Hantush, 1960)..Initial treatment of the data indicates that the Hantush r/B method, which assumes no storage in the aquitard, is the appropriate technique for evaluating these data. The solution involves curve matching in which a log-log plot of the. drawdown is compared to a family of type curves. Each type curve in the family of curves is associated with a unique r/B value, which determines the amount of leakage through the semi-permeable beds. After matching the data to the correct type curve, the aquifer conductivity, K,- and the specific. storage, Ss, may be ` calculated with: ` K— QW(u,rl B) I 47rbs f 4tKb I Ss= } r2(1/u) I SF010030962.DOC 3-8