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! FLAG CITY CHEVRON Ground Water Pump Test Calculations w � Assumptions: r • Pump Test No.`1: extraction from EW-2 at constant ground water pumping rate of 4.0 GPM �- • Pump Test No. 2: extraction from EW-2 at constant ground water pumping rate of 6.6 GPM • ground water Pump Pump Test No.3: extraction from EW-2 at constant Pumping rate of 10.0 GPM • Pump Test No.4: extraction from EW-3 at constant ground water pumping rate of.10.0 GPM • The Jacobs Straight Line Method (Distance-Drawdown Method) can be utilized to calculate transmissivity(T) and specific yield utilizing draw-down versus distance on semi- F: logarithmic paper for each well location(Appendix F). T=transmissivity; S =specific yield Q=constant ground water pumping rate. 4s=draw-down per I-logarithmic cycle. t=time of pump test Fr9=intercept of best fit line with the distance axis FPump Test No. 1: Q = 4.0 GPM; As = 2.7 ft.; t= 60 minute• r — 1 f� © 7 ft. 1 T=70Q=Q s -4 70(4.0 GPM) �2.7 ft=104 fe/day r T= 104 ff2/day x I gpd/ft_ 0.134 fl/day=774 gpd/ft S = T(t)� 640 (ro)2 = (104 ft2/da 60 min — 640 17 2 — Y){ ) � ( ){ ) —0.034 Pum — Pump Test No. 2. Q = 6.6 GPM; As = 4.8 ft.; t= 600 minute; ro = 20.5 ft. T=70Q-as -+ 70(6.6 GPM) 4.8 ft=96.25 ft/day T =96.25 ft/day x 1 gpd/ft 0.134 ftz/day-=718 gpd/ft S =T(t) -640 (ro)2= (96.25 fl/day)(600 min)=(640)(20.5)2 =0.21 i Pum Test No. 3: } P Q = 10.0 GPM, As = 6.3 ft., t= 1.00 minute; ro = 24 ft. T=70Q--As -4 70(10.0 GPM) �6.3 ft= I11 ft2/day T= Ill ftz/day x 1 gpd/ft-0.134 fl/day=829 gpd/ft S =T(t) _640 (ro)2= (111 ft /day)(100 Iain) (640)(24)2 =0.03 w { Pump Test No. 4: Q = 10.0 GPM; As = 3.8 ft.; t= 400 minute; ro = 33 ft. T= 70Q=0s -+ 70(10.0 GPM) � 3.8 ft= 184 ftZ/day �. T= 184 ft2/day x 1 gpd/ft_ 0.134 ft/day= 1;375 gpd/ft S = T(t) _ 640 (ro)2 = (184 ft2/day)(400 min)_ (640)(33)2 Advanced GeoEnvironmental,Inc.