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1 <br />' Ground Water Drawdown Test Calculations <br /> JIMCO TRUCK PLAZA <br />' 22502 South Highway 99, Ripon, California <br />' Assumptions <br />' 0 A constant ground water pumping rate of 6 GPM for tests conducted in June 2002 <br /> • Well EW-1 is screened entirely through the upper water table of 21 feet fioml6 to 36 feet <br />' a Homogenous ground water aquifer characteristics at observation wells MW-1 through <br /> MW-9 <br /> • The Distance-Drawdown Method was used to calculate transmissivity (T) and storativity <br />' (S) and hydr aulrc conductivity (K) utilizing draw-down versus distance (feet) on semi- <br /> loganthrruc paper for each well location <br />' 0 Equations <br />' T = 70Q/ds S = Tt/640 (ro)2 K= T/b <br /> Where <br />'• K=hydraulic conductivity <br /> T =transmissivity <br /> S = storativity <br />' Q = constant ground water pumping rate = 6.0. GPM. <br /> As = draw-down per 1-logarithrruc cycle (Appendix *) = 0.42 ft <br /> t =time of pump test (Appendix #) = 2,880 minutes <br />' ro =Intel cept of best fit line with the distance axis (Appendix#) W 160 feet <br /> b= aquifer thickness 15 feet (semi penetrated or exposed screen length) <br />' 14 June 2002 <br /> T = 70 (6 gpm) / 0 42 feet = 1000 feet'/day or <br />' 1,000 feet2 /day (1 gal day/ft/0 134 feet2/day) = 7,462 gal day/feet <br /> S = 1,00 feet' /day(2880 minutes) /640 (160 feet)2 = 0 175 <br /> K= 7,462 gal day/feet / 15 feet = 497.5 feet/day <br />' K= 497 5 feet/day (1 cm/sec/2835 feet/day) = 0 175 cm/sec <br /> I <br />' Advanced GcoEm ironmental,Inc <br /> I <br />