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1 <br /> <br />1 <br /> <br /> <br />t <br />t <br />1 <br />1 <br /> <br />1 <br />t <br /> <br />1 <br /> <br /> <br />1 <br />1 <br /> <br />Following well construction, a 4-hour constant dischazge pumping test was performed. During the <br />test, the well was pumped at a constant discharge rate of about 1.02 gpm. Water levels were <br />measured in the pumping well and in the observation well at specified time periods during the test. <br />A pumping rate of 1.02 gpm was chosen because of well yield and pump constraints. Because of <br />the drilling method used, the well was probably never fully developed (cleaned of fine materials), <br />and was consequently slightly plugged. The inefficiency of the pumping well, how~:ver, did not <br />prevent measurable water level changes in the observation well, which were used to determine <br />aquifer characteristics. <br />The water level drawdown data for the pumping and observation wells are sttrnmarized in <br />Appendices D and E, respectively; and Appendices F and G present drawdown versus lime plots for <br />the pumping and observations wells. The drawdown data were analyzed using stand;trd, accepted <br />methods, including the Theis equation and the Theis type-curve matching technique. This method <br />indicated that the transmissivity of the alluvial aquifer at this location is about 10,627 gallons per <br />day per foot (gpd/ft), and the storage coefficient is about 0.005. The low storage coefficient is <br />expected given the semi-confined nature of the aquifer. The hydraulic conductivity ~~f the aquifer <br />was estimated based on the calculated transmissivity and the aquifer thickness of .bout 10 feet, <br />indicating that the hydraulic conductivity of the aquifer is about 1,063 gallons per day per foot <br />squared (gpd/ft'}. <br />Additional pumping test data from a nearby well, permit number 123108-A (the Shupe well, Well <br />No. 13 on Figure 2), were also analyzed using the Theis type curve method. The data from that test <br />are presented in Appendices H and I. Permit number 123108-A was constructed with the intent of <br />providing along-term reliable water supply for the Shupe residence; accordingly. the well was <br />completed with stainless steel well screen and a gravel pack, which is much more efficient than other <br />types of well construction. An observation well was not used in this pumping test, gut because of <br />the efficient welt construction, the data are reliable for the purposes of calculat ng an aquifer <br />transmissivity. Anal}~sis of the data indicate an aquifer transmissivity of about 8,996 gpd/fr and a <br />storage coefficient, representative of conditions in the pumping well, of about 0.0003. The satwated <br />12- <br />lli,./rr~~lSir~Zr$'u .l.~~n/ire/i ,, l//~. <br />