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4-9 for observation points Nf-W-1 VfW-2 and PZ-1 It can be seen that the data deviate from the Neuman type curves at early times on the plots for PZ-1 and MW-1, which is characteristic of wells experiencing casing storage effects Values of T and S, were also calculated using the drawdown versus distance method of Cooper and Jacob (1946) from the data shown on Figure 10 Table E1 shows the transmissivity and storage coefficient values calculated from each of these plots along with the early time elastic storativity (S) and beta values obtained from the Neuman plots (Figure 5, 7 and 9) The transmissivity value calculated from production well RW-1 drawdown (Figure 3) are not valid due to the effects of partial penetration and are not shown on the table The calculated transmissivity values from the observation well data ( 09 - 24 ft2/min) differ somewhat which may be due to actual variations within the water-bearing zone. Well logs at the site 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 the pumping well RW-I after approximately 20 - 40 minutes (Figure 3) 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 analyses depicted in Figures 5,7 and 9 The early time storativity (S) calculated from this analyses (Table E1) is applicable to the early pumping time prior to significant dewatering of the aquifer. The Sy (specific yield) value shown on the figures and on Table E1 is representative of the long-term volume of water released from storage per unit surface area per unit decline in the water table The calculated values of 1 to 3 percent are consistent with the unconfined silts encountered in site borings Some irregular fluctuations in the water table responses were noted during testing,particularly in well RW-1 at approximately 100 -300 minutes and 1100 - 1400 minutes. These changes may be due to variations in the pumping rate, but may also reflect response to tidal/river stage changes and/or nearby production well pumping The lack of strong correlation between these water elevation changes in RW-1 and the observation well responses suggests pumping rate variation is largely responsible The Neuman type curve analysis computes a beta value (B) which is equal to B = r'k„ where DZk.1, r = distance of observation well to pumping site d — saturated thickness of water-bearing zone k, = vertical hydraulic conductivity kh — horizontal hydraulic conductivity The data from piezometers PZ-I and wells MW-1 and MW-3 yielded B values of 0 03,0 2 and . 3 0, respectively Using the previously stated equation, this indicates ratios of horizontal to