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XMIMM <br /> XV <br /> 10MM <br /> .V- <br /> 1 <br /> will be linear. The storage coefficient and <br /> transmissivity of the aquifer can be determined by the <br /> following equation: <br /> S W 2.2.5 T to/(r2) {6} <br /> where: to = intersection at 0 drawdowr on time axis of <br /> extended straight line portion of the graph <br /> and: <br /> T = 2.3 Q/ (4lTas) . . . (7) <br /> where: As drawdown change over 1 log cycle of the <br /> straight line portion of graph. <br /> si Equation 7 enables the calculation of T, which when <br /> substituted along with to and r in Equation 5 i <br /> �N , yields S. <br /> The Cooper-Jacob solution is valid if u is less or equal <br /> to 0.01. If r is relatively small, the condition will <br /> normally be met after one hour of pumping (Bouwer, 1978) . <br /> - $ate-Of-Ri GP T -c'}�nirn�ac <br /> The in-situ hydraulic conductivity values can be <br /> determined by means of tests performed in a single well or <br /> Piezometer, The test is initiated by causing an <br /> instantaneous change in the water level in a well through <br /> ^fit a sudden introduction or removal of a known water volume. <br /> The recovery of the water level with time is then <br /> observed. When water is removed, the tests are often <br /> m called bail tests; if the water is added, it is known as a ' <br /> slug test. The procedure requires the use of a sensitive <br /> pressure transducer with the probelaced just off h <br /> bottom of the well. Water is then immediately introduced <br /> Ii� or removed from the well, and pressure readings are <br /> recorded versus time. <br /> �.g Bouwer and Rice (1916) developed a procedure for <br /> I estimating the hydraulic conductivity (K) based on the <br /> response of the well to a sudden change in the water <br /> table. The hydraulic conductivity can be calculated as <br /> follows: <br /> K = r•ln(R/r,,) •ln(ro/Yt) I (2L t) (8) <br />