Laserfiche WebLink
HydroGeo Consultants <br /> 1 <br />' Corrected drawdown was calculated using the formula <br /> s'= s- s2/2b <br />' Where <br /> s' = corrected drawdown <br /> s = actual drawdown <br />' The velocity of groundwater is determined by the formula <br /> v=Ki/n, <br />' Where <br /> v = velocity (ft/day) <br /> I = groundwater gradient(0 0065, February 13, 2002) <br /> ne = effective porosity (assumed 30% for silt/sand) <br />' The downgradient stagnation point (or distance downgradient that water will be captured <br /> by the pumping well) estimated from the transmisszvity is determined by the formula <br /> R= Q/27rT1 <br />' Where <br /> R = downgradient stagnation point <br />' Q = pump rate (gallons/day) <br /> T = transmissivity (gallons/day/foot) <br />' In addition to the Jacob method described above, the Jacob distance drawdown method <br /> was also used since a drawdown response was observed in most of the wells at the Site <br />' This method plots the maximum drawdown in feet observed at each observation wells in <br /> log scale on the x-axis against the distance in feet from the pumping well to each <br /> observation well on a linear scale on the y-axis The capture zone radius of influence can <br />' also be obtained from this graph by obtaining the distance in feet where drawdown is <br /> equal to zero (ro) or where the best fit line intersects the x-axis Transmissivity and <br /> hydraulic conductivity were then also calculated using the following formulas <br />' T= 70Q/ds <br />' K= T/b <br />' Thrifty Dol TOC#171 Aquifer Test and RAP Rpt Page 7 <br />