Laserfiche WebLink
Working To Restore Nature <br /> The transmissivity calculated according to the theoretical specific capacity/transmissivity <br /> relationship is 13,300 gpd/ft Averaging the transmissivity values derived from the Jacob <br /> equation and from the theoretical specific capacity relationship, the estimated value of formation <br /> transmissivity, based on this pumping test, is approximately 11,300 gpd/ft A review of the log <br /> for pumping well MW-4 indicates an aquifer thickness of approximately 10 feet. The resulting <br /> hydraulic conductivity is approximately 1,130 gpd/W. This value corresponds to the upper to <br /> ' middle range of expected values for sandy aquifers. <br /> Well Efficiency: <br /> Well efficiency, expressed as a percentage, is defined as the ratio of observed specific capacity <br /> to theoretical specific capacity (calculated from transmissivity) Efficiency for the tested well <br /> was determined according to this method <br /> The specific capacity (Q/s) observed from the drawdown data at t=10 minutes is: <br /> MW-4 = 3 gpm/1.074 ft = 2.79 gpm/ft <br /> A specific capacity h (at t = 10 min) was calculated from the theoretical relationship: <br /> ' Q/s = 11,300/{264 log [0.3 (11,300) (0 0069)/(0 52) (0 2)]} = 16.0 gpm/ft <br /> ' Well efficiency = Observed Q/s = 2 79 = 17.4% <br /> Calculated Q/s 16.0 <br /> 1 <br /> These data indicate that the 2-inch diameter, 0 020 inch slot well is quite inefficient. <br /> iApproximately 84% of the total drawdown results from casing storage. For example, of the <br /> total drawdown after 10 minutes of pumping (1 074 ft), 0 891 ft was due to well loss. The step <br /> rtest data indicate that turbulent flow accounted for 36% of the total drawdown of 1 074 ft, or <br /> 0.387 ft. The well loss attributable to laminar flow was approximately 0 504 ft (0 891-0.387), <br /> 1 <br /> 15M8XREPO AC"moa DRF 10 <br /> 1 <br />