Laserfiche WebLink
06/24/2002 15 42 2094671118 AGE STOCKTON PAGE 10 <br /> Ground Water Drawdown Test Calculations <br /> FORMER STOCKTON PLATING FACILITY <br /> 632 South El Dorado Street, Stockton, Calrfoxxaxa <br /> Assumptions <br /> • A constant gi ound water pumping i ate of 5 GPM for tests conducted on 18 October 2001 <br /> • Well EW-I as screened entirely through the uppez water table, 30 to 60 feet bsg <br /> • Homogenous ground water aquifer charactemtxcs at observation wells MW-3 through <br /> MW-5, vapor wells VW-1 to VW 4 and ground water extraction well EW-1 <br /> • The Distance-Drawdown Method was used to calculate transrrossivity(T) and storativlty <br /> (S) and hydraulic conductivity (K) utilizing draw-down versus distance (feet) on serru- <br /> logar ithmic paper fox each well location <br /> • Equations <br /> T= 70Q/ds S = Tt/640 (r,,)2 K=T/b <br /> Where <br /> K=hydi aulxc conductivity <br /> T= transmissivity <br /> S = stoz ativity <br /> Q = constant gx ound water pumping x ate = 5.0. GPM <br /> As = draw-down pet 1-logar-ithrmc cycle (Appendix Id) = 0.92 ft. <br /> t= tune of pump test (Appendix G) = 720 minutes <br /> ro= intercept of best fit line with the distance axis (Appendix H) = 100 feet <br /> b= aquifet thickness (senna penetrated or exposed screen length) <br /> 18 October 2001 <br /> T= 70 (5 gpm) 10 92 Feet= 380 feet' /day ox <br /> 380 feet2/day (1 gal day /ft/0 134 feet' /day) = 2,840 gal day/feet <br /> S = 380 feet'/day(720 minutes) 1640 (100 feet)' = 0 043 <br /> K= 2,840 gal day/feet / 30 feet = 94 feet/day <br /> 1C= 94 feet/day (lcmisec/2835 feet/day) = 0 033 cm/sec <br /> ,4dvanCed GCVEn V9UMent01 lnc <br />