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modified type curves. No good matches could be achieved. The • technique assumes radial inflow into the well bores. Recovery plots for aquifer tests of wells GW-N9 and N15 suggest that fracture flow may be significant. The first few recovery measurements for the GW-N13 aquifer test appear to have been measured wrong as their extension would intersect the y axis at a S~So ratio of 0.9 rather than approximately 1. The test data were then analyzed using the alternate method described (successive approximations) and values of 58 ftz day-1 , 4.6 ft2 day-1 and 13.4 ft2 day-1 for transmissivity were calculated for monitor wells GW-N9, N13, and N15, respectively. Tables 24, 25, and 26 present the incremental afterflows, time and water level values for monitor wells GW-N9, N13, and N15, respectively. Because the successive approximation technique yields more accurate transmissivity results when there is at least 70 • percent aquifer contribution and the above-mentioned tests involved less than 70 percent aquifer contribution, another attempt was made to compute a transmissivity value for well GW-N13 using the curve matching technique which is designed for tests where less than 70 percent aquifer contribution is achieved. Electric tape reading errors were assumed to have caused the discrepancy on the early recovery portion of this test; as a result, the first five drawdown values were adjusted by one foot. A very good match with curve was made and a transmissivity determined for well GW-N13. This "T" v. of "T" values determined using the approach and strongly suggests that aquifer test values. the 10-5, Tto/rc2 = 250, value of 52 ftz/day was slue falls within the range successive approximation these are representative The low yielding and discontinuous nature of the shallow ground water system at the Nucla mine are not conducive to textbook-style • aquifer tests. The results of the tests performed to date support 83