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The static hydraulic heads measured in the drill holes are given in Table 2. The <br />measured hydraulic heads represent mix of heads over the length of the boreholes and <br />it is not possible to precisely relate the hydraulic head to distance from the American <br />Tunnel. However, it is clear that the hydraulic head in the vicinity of the tests is <br />generally approximately 300 feet higher than the American Tunnel. <br />The area of the test is relatively highly fractured and serves to drain water from the <br />fractured bedrock into the mine. Hence, the measured hydraulic heads do not <br />represent the static equilibrium that would exist without the mine workings, but, <br />rather, a cone of depression induced by the presence of the mine. <br />5.4 Estimate of Hydrau/ic Conductivity <br />Both log-log and semi-log plots of the rate of pressure change with time during the <br />flow periods for holes 700, 702, and 704 (first test) and hole 781 (second test) are <br />given in Appendix A, Semi-fog recovery plots of pressure build-up versus t/t' (time <br />since flow began divided by the time since flow was terminated) also are included. <br />The drawdown plots for the first test do not provide for simple analysis by the Theis <br />or Cooper-Jacob (1946) methods. This is probably due to turbulent flow within the <br />small-diameter, uncased longhole thole 700) and boundary effects along the highly <br />transmissive fractures. Hole 700 drawdown data shows a more atypical plot than the <br />drawdown data from holes 702 and 704. <br />sunnylwpltraci122511Mar1993.Rpt 31 <br />N~! SIiT10f1 HYDRO-SEARCH <br />