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'am,WWI • Working To Restore Nature design and construction, including the utilization of a larger slot size should improve well performance This, however, might result in the production of some silt during pumping which could require surface filtration Test Results: Long-Duration Constant Rate Test Because a large component of the drawdown in well PTW-1 during the long-term test was due to well loss, the actual drawdown in the formation away from the production well was relatively small This is clear from the observation well drawdown versus time plots (Plates 4-PT and 5-PT),which showed total drawdown ranging from 0 12 foot in well MW-6 (85 feet from well PTW-1) and 0 39 foot in well MW-7 (13 feet from well PTW-1) Well drawdown versus time plots (both log-log and semilog plots) were prepared for observation wells MW-6 and MW-7 (Plates 4-PT, 5-PT, 9-PT, and 10-PT) Plate 8-PT presents the drawdown in wells MW-6, MW-7, and MW-11 after 980 minutes of pumping versus their respective distances from the pumping well (PTW-1) Table E1 shows the transmissivity and storage coefficient values calculated from these plots using the methods of Copper and Jacob (1946), and Neuman (1972) Transmissivity value calculated from production well PTW-1 drawdown are probably not representative due to the effects of partial penetration The calculated transmisstvity values • from the observation well data may differ due to actual variations within the water-bearing zone Well logs support this interpretation of heterogeneity and anisotropy The calculated early time storativity and specific yield values also vary somewhat but are clearly indicative of unconfined conditions No identifiable boundary conditions were detected in the test data There is, however, a noticeable decrease in the rate of drawdown in observations wells MW-6 and MW-7 after approximately 20 - 40 minutes (Plates 4-PT and 5-PT) This slope change is probably due to the effect of dewatering which results in a small amount of delayed drainage in the unconfined aquifer This effect is common in unconfined, vertically stratified aquifers and is accounted for in the Neuman type curve analysis depicted in Plates 9-PT and 10-PT The early time storativity (S) calculated from this analysis (Table E1) is applicable to the early pumping time prior to significant dewatering of the aquifer The Sy (specific yield) value shown on the plates and on Table E1 is representative of the longterm volume of water released from storage per unit surface area per unit decline in the water table The calculated values of 5 percent and 9 percent are consistent with unconfined silty and well- graded sands • 38032-10