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Appendix C Slug TesR Procedures CJ TEST PROCEDURES URS Greiner Woodward Clyde (URSGWC) conducted slug tests on three wells MW-1, MW-6, and MW-11 The purpose of the slug tests was to estimate the transmissivity and hydraulic conductivity of the water-bearing strata screened in the well, and to evaluate the variability of these parameters Slug testing induces a relatively instantaneous stress within the water-bearing unit(s), resulting in an increase or decrease in water level The resulting return in water level to equilibrium conditions enables an estimation to be made of transmsssivity and hydraulic conductivity values These hydraulic parameters are specific to the zone(s) directly adjacent to the tested well because the induced stress occurs over a few feet from the well casing, at most Slug tests were performed on the wells by inserting a solid mandrel (representing a "slug" or volume of water) into the well casing such that the mandrel was immersed in the water The mandrel was constructed of PVC pipe capped at each end and filled with sand to compensate for buoyancy Prior to inserting the slug into the well casing, the depth to static water level was measured using an electronic water level sounding (probe) device The total depth of the well was measured and the height of the water column in the well was calculated A pressure transducer is typically placed into the well near the bottom of the well casing and connected to a data logging device The pressure transducer should be placed at a depth that was both within the range of the transducer's sensitivity and allowed for submersion of the mandrel without damage to the transducer For this project, a pressure transducer was not shipped to the site since rain was anticipated, rain would damage the computer used to record and analyze the slug test data Therefore, slug test data (rising head and falling head) were recorded using a stop watch and electronic water level meter The mandrel was quickly lowered into the well casing to provide an "instantaneous" rise in water level Periodic measurements of the recovery (falling head) of the water level in the well casing were measured using the electronic water level meter, and the measurements were recorded in a field log book After allowing sufficient time for the water level in the well to approach initial static level, the mandrel was quickly extracted from the well casing and recovery (rising head) measurements were made as described for the falling head portion of the test Once a slug test was completed, the data were transferred to a computer for analysis and interpretation purposes T 11 9 99541-040 1 0004 slocktonkWuglestApp-cdoc523 NOV-9958840173A5SNA C-1