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' Appendix C Slug Test Procedures C I TEST PROCEDURES ' URS Greiner Woodward Clyde (URSGWC) conducted slug tests on three wells NIW-1. NIW-b, and NIW-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 vanabiliry 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 trarismissivity 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 iri the water The mandrel was constructed of PVC pipe capped at each end and tilled with sand to compensate for buovancv 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 istYP ically placed into the Weil near the bottom of the well casing and connected to a _ data lovains? device The pressure transducer should be placed at a depth that was both within ' the range of the transducers sensitivity and allo«ed 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 fading head) ,-,ere recorded using a stop watch and electronic water level meter ' The mandrel vas quickly to-,tiered into the «ell caging to provide an 'instantaneous rise in water le.el Periodic measurements of the reco,,erg (falling head) of the water level in the tivell casing v.ere measured using the electronic water level meter and the measurements were recorded in a field log book -�fte: allmving, sufficient time for the «ater level in the well to approach initial static level the mandrel «as quickly emractea frorr; the «ell casing and reco,,er, (rising head) measurements *,%ere made as descnbed for the failing dead portion of the test _ �,� :t:�ed t�� a coin uter for anaks�s and ' Ong. „ s1La teat «a� comcietec. the Baia � ti-an_ P zz;7:re,,acior: purposes