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0 • in an analog model the resulting draw downs are considered to be additive The model indicated that the flow at MW 1 would be great enough to significantly effect the response of the upper aquifer while not significantly effecting the lower It also indicated that the presence of the cross- zonal well would make the de-watering of the upper zone impractical ASSUMPTIONS FROM LITH®LOGY AND GROUNDWATER MEASUREMENTS. Both the A-Zone and the B-Zone are under confined conditions The groundwater head has come to an equilibrium state on-site because of the presence of the cross-zone wells Further away from the site in MW6A and MW6B there is a difference of 0 02 feet between the pressure head in the two zones Examination of the lithology of the two zones indicates that there should be a significant difference in the hydraulic conductivity (K) of the two zones The A-Zone with its silty to clayey sands should have a much lower K than the B-Zone with its clean sands This difference could be up to two orders of magnitude The top of the A-Zone is at an elevation that a high pump rate combined with the lower expected K could cause the aquifer to pass from the confined to the unconfined conditions with the lowering of the groundwater head by approximately 3 feet PLAN FOR PUMP TEST With the proposed destruction of MW1, X W2, and MW3, some modification must be made in the original pump test plan Because of the confined/semi-confined nature of the water bearing zones at this site, it is advisable to collect baseline groundwater head data prior to performing the pump test The zones being in a confined state, the potentiometric head will respond both to changes in the barometnc pressure, tidal influences and surface loading on the adjacent ground surface In order to help determine the possibility of these effects on the system, pressure transducers will be placed in MW6A and MW6B a week prior to the pump test Because of the complex interaction of the two groundwater zones and the interconnecting wells a number of test will be preformed In order to test the possibility of de-watering the A-Zone in the old tank pit area a step draw down test wall be performed in RW 1 A. A step draw down test will be performed in RW01B, to test the possibility of de-watering the area next to old pit into the top of the B-Zone In order to gain some knowledge of the actual aquifer parameters of A and B Zones, constant rate drawdown tests will be performed in MW6A and in MW613 STEP DRAWDOWN TEST RWIA. 40 In order to get some idea of the practicality of de-watering the A-zone sand a step drawdown test will be performed in RW1A. The test will be performed by placing a vanable speed Grundfos 2 Red Pump Test Plan-Appendix A, 1/10102