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' TABLE 4 <br /> 1 .3 <br /> PUMP TEST RESULTS AND INTERPRETATIONS <br /> .IAMAR <br /> 4075 E MAIN STREET <br /> STOCKTON,CA 95212 <br /> Limited Step Drawdown Test on EW-I was conducted on 5/22/03. The 3 gallons per minute portion of the test <br /> was used for evaluation. From the step test it appears that 2.5 gallons per minute will be an optimal pumping rate. <br /> A standard time drawdown semi-log plot was prepared and a transmissivity was calculated to be about 147 ft2/d or 1099 gal./day/ft <br /> using the Theis non-equilibrium equation as modified by Cooper and Jacob. <br /> For purposes of evaluating drawdown awayfrom the pumping well,—tliis method wasconsidered-the most accurate. <br /> The formula: s=264Q/T x log(.3Tt/r2S),where <br /> S = drawdown in feet <br /> Q= well yield in gallons per minute <br /> T= Transmissivity in gallons per day per foot <br /> t= Time in days <br /> r= Radius in feet <br /> S= Storativity <br /> A value of 0.1 or 10 percent was used for the Specific Yield/Storativity value. The material that the groundwater was being pumped <br /> from was assumed to be the unconsolidated silt to silty sands described from boring logs of EW-1. A Storativity/Specific Yield <br /> of 0.1 from an unconfined aquifer was considered reasonable for the purpose used. <br />-- Drawdown-calculations•were performed-for,radii-of-10,-50•and-100-feet-from•the pumping-well These-calculations essentially-include--- <br /> the entire JAMAR site. The durations of pumping were 30, 60, 100 and 365 days. These times were considered to be adequate to <br /> demonstrate how pumping at this site could effect the movement and containment of any impacted groundwater beneath the site. <br /> DISTANCE DRAWDOWN CALCULATIONS <br /> (feet) <br /> TIME RADIUS(feet) <br /> (days) 10 50 100 <br /> 30 2.16 1.15 _ 0.72 <br /> 60 2.38 1.37 0.93 - <br /> . <br /> 100 2.54 1.53 _ TA9. <br /> 365 2.94 = 1.93 .. =::1:50 <br /> Extrapolated drawdown values are reasonable;during one hour of testing at 3 GPM on EW-1,groundwater influence was shown in <br /> MW-4(30 feet away) 0.2 feet of influence; MW-1 (35 feet away)0,04 feet of influence;MW-2 (85 feet away)0.01 feet of influence. �l <br /> There was no influence in MW-3 (147 feet away). <br /> G:1Data151871Distance Drawdown Calculations <br />