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Measuremenf and Analysis -The procedure for determining the <br />• transmissivity in the Moffat Area by o drawdown -recovery pump test method was <br />based on obtaining the maximum drawdown possible of o low pumping rate. This <br />insures a well defined cone of depression over a sustained period of time. Water <br />levels in the wells were taken several times previous to the test to obtain a static <br />equilibrium. After the submersible pump was placed in the well the purnp was <br />started briefly to fill the discharge lines and The water level in the well was allowed <br />to equilibrate before the Test was begun. During the drawdown portion of the test, <br />the pump was throttled to obtain a constant flow rate while water levels were <br />recorded at frequent time intervals. After The intended drawdown had been reached <br />the pump was stopped and recovery levels were recorded until recovery was 90 <br />percent complete. If observation wells were present the water level in these wells <br />were recorded during the entire test. A flowmeter on the pump discharge line was <br />used to determine the total amount of water pumped. transmissivity values were <br />calculated from the recovery data developed during the pump test. The procedure <br />takes full account of well bore storage. <br />The auger hole test for determination of the hydraulic conductivity of the <br />alluvium on Trout Creek consisted of quickly evacuating the water from the well and <br />then recording the rate of recovery of water in the well. As in the purnp test <br />procedure, water levels were taken several times previous to the actual test. A <br />portable centrifugal purnp was used to displace the water from the well. The well <br />was pumped so that drawdown was equal to or greater than half the original static <br />water level. The water levels were recorded by an automatic float system. <br />Calculation of the hydraulic conductivity was accomplished by the method developed <br />by Boast and Kirkham, 1971. <br />Flow recorders on the sirearn were used to develop hydrographs for the study <br />period through stage-discharge analyses. The flow recorders on the two ditches were <br />used to develop hydrographs and the total amount of water diverted from Trout <br />Creek through a known stage-discharge relationship. Stage~ischarge relationships <br />were developed for stream flow at each gaging station through o series of flow <br />measurements providing discharge values at different stages. Stream discharge <br />measurements were made with acurrent-meter as described in Book 3, Chapler A6, <br />General Procedure for Gaging Streams, Techniques of Water-Resources Investigations <br />of the United States Geological Survey, 1968. The stage-discharge relationship for <br />a particalar station was determined by a logarithmic least squares linear regression. <br />The relationship was then used to prepare the hydrographs. <br />Four water quality samples were taken from each sample location. Two <br />2.5-109 <br />