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D <br />Appendix E <br />PERMEABILITY TESTING <br />Aquifer tests, consisting of falling- and rising -head slug tests, were conducted in two <br />site monitoring wells (MW -1 and MW -4) to determine the hydraulic conductvity of the <br />deep and shallow water -bearing zones. MW -1 is installed in the deep regional water <br />-bearing zone and MW -4 is installed in the shallow perched water -bearing zone. <br />Hydraulic conductivity values obtained from the slug test represent "point <br />measurements", and provide an evaluation of the aquifer permeability in the vicinity of <br />the well bores. <br />Slug testing involves inserting or removing a "slug" or object of known volume into the <br />well creating an instantaneous change of water level. At this site, a galvenized steel slug <br />10 feet in length and 1.25 inches in diameter was used in the two-inch diameter well. In <br />the deep monitoring well (MW -1) a PVC slug 20 feet in length and 2 inches in diameter <br />was used. In both tests the slug was quickly lowered into the well and the changes in <br />water level were measured while the level returned to static (falling head test). After the <br />water level stabilized, the slug was removed and levels were again monitored as they <br />returned to the original static water level (rising head test). When conducting falling <br />head tests, water is introduced into the unsaturatd zone, and results man not reflect the <br />true properties of the saturated zone. The falling head test is used, however, for <br />comparison with the rising head test. <br />Both falling and rising head tests were conducted at wells MW -1 and MW -4. MW -4 is <br />completed in the first encountered water -bearing zone which is considered to be <br />unconfined. MW -1 is completed in the second encountered water -bearing zone which <br />may be under semi -confined to confined conditions. <br />Slug test were analyzed using a method described in the U.S. Navy Design manual <br />(DM -7), March, 1971. <br />Results of slug testing indicate hydraulic conductivities (k) of 8.11 X 10-5 centimeters <br />per second (cm/sec) and 4.58 X 10-5 cm/sec for monitoring wells MW -4 and MW -1 <br />respectively. Plots of the water level changes during the falling and rising head portions <br />