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Table 23 <br />CDCR EW-2 Hydraulic Capture Estimation <br />Forward Landfill, Manteca, California <br />Test <br />Pumped <br />Well <br />Pumping Water- <br />Bearing Zone <br />Saturated <br />Thickness1 <br />(ft) <br />Transmissivity <br />(T) <br />(ft2/day) <br />Hydraulic <br />Conductivity <br />(K) <br />(ft/day) <br />Hydraulic <br />Gradient2 <br />(i) <br />Pumping <br />Rate <br />(Q) <br />(gpm) <br />Pumping <br />Rate (gal/d) <br />Pumping <br />Rate (ft3/d) <br />USEPA <br />Radius of <br />Capture3 <br />(Ywell, ±ft) <br />USEPA Well <br />Capture <br />Width <br />(ft) <br />USEPA <br />Maximum <br />Radius of <br />Capture4 <br />(Ymax, ±ft) <br />USEPA <br />Maximum <br />Upgradient <br />Capture Width <br />(ft) <br />USEPA <br />Downgradient <br />Capture <br />(X0 <br />5 ft) <br />24.5 35,280 4,717 107 213 213 426 68 <br />30.0 43,200 5,775 130 261 261 522 83 <br />40.0 57,600 7,701 174 348 348 696 111 <br />50.0 72,000 9,626 217 435 435 870 138 <br />Notes <br />2 - Hydraulic gradient calculated from average groundwater flow, but varies from 0.001 up to 0.003 depending on the season <br />3 - Lateral plume capture from well location per USEPA (2008) capture zone evaluation guidance [Ywell = ±Q/4Ti]. <br />4 - Upgradient maximum lateral plume capture per USEPA (2008) capture zone analysis [Ymax = ±Q/2Ti]. <br />5 - Downgradient maximum plume capture per USEPA (2008) capture zone analysis [Xo = Q/2πTi]. <br />USEPA - United States Environmental Protection Agency <br />ft - feet <br />ft/day - feet per day <br />ft2/day - square feet per day <br />gpm - gallons per minute <br />Capture zone method from USEPA 600/R-08/003 <br />Q - Discharge <br />T - Transmissivity <br />i - Hydraulic gradient <br />y well - width of capture adjacent to the extraction well <br />y max - maximum upgradient capture by the extraction well <br />X0 - Stagnation point downgradient of the extraction well <br />1 - Saturated thickness for shallow zone calculated from thickness of higher permeabillity sands present in the screen interval. <br />CDCR-EW-2 <br />Shallow / <br />Intermediate <br />Groundwater Zone <br />60 5,534 92 0.002 <br />Ti <br />Qywell4= <br />Ti <br />Qy2max= <br />Ti <br />Qx20= <br />Page 1 of 1