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water table to be present or no significant piezometric <br />• pressure). This assumption would appear to be consistent with <br />information provided by test borings on-site as all the holes <br />within permit boundaries were reported to be dry. Obviously, <br />this assumption has a substantial effect on the calculated <br />numerical values for factors of safety. However, of concern in <br />this study is not so much the actual value of factor of safety, <br />so much as the relative change in factor of safety between pre- <br />and post-subsidence conditions. The dry state of the bedrock <br />above the mine level would also seem to be supported by <br />observations within the mine. Seepage within the mine is limited <br />to a 200- to 300-foot thick zone near the surface. Within this <br />region, only a short distance in from the portal area, seepage is <br />relatively common and directly related to precipitation events on <br />• the surface. Below this level mine conditions are dry. In order <br />to examine the effect of this zone on stability of the near- <br />surface bedrock, stability analyses were performed assuming this <br />300-foot thick zone to be fully saturated to the surface. <br />Circular search routines disclosed a factor of safety of 1.53 for <br />typical strength parameters, or for the worst case, 1.11 using <br />conservative strength parameters (see Table 2). <br />In addition to analysis of the overall stability of the hillside, <br />cross-sections CC' and DD' (Figure B6) were utilized to analyze <br />stability conditions in known areas of instability. The results <br />of these calculations can be found in Table 3. For the <br />. calculations performed, shear strength values for slide debris in <br />the vicinity of the Bear Mine No. 3 portal obtained in earlier <br />22 <br />