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drilled in and close to it. The embankment crest elevation is 6795 <br />• feet, and maximum water level is 6786 feet, the principal spillway <br />elevation. An emergency spillway elevation has been established at <br />6788.3 feet. Figure 2 also includes a fence diagram projection of <br />subsurface conditions interpreted from three test holes, TH-22, <br />TH-24 and TH-25; TH-23 is not shown in this illustration. This <br />projection shows a subsurface sandstone which appears to be <br />restricted to the western and northern parts of the pond area. The <br />sandstone is found in TH-22 and TH-24, but apparently pinches out <br />between these two holes and TH-25 since it was not found in the <br />latter hole. The sandstone also pinches out between TH-24 and -23 <br />(Fig. 3). This relationship of the sandstone is also shown in <br />cross sections B-B' (Fiq. 3) and in cross sections C-C' and D-D' <br />(Fig. 4). Excavation for the left abutment of the embankment <br />• likely will encounter sandstone, and(or) sandier material than is <br />found in the right abutment. <br />The right abutment of the embankment should be in weathered <br />shale and clay; the left abutment is shown on the map to be in <br />Alluvium, but it likely is close to weathered shale bedrock and <br />possibly detrital sand or sandstone. It is not likely that a <br />design incorporating a bedrock keyway in the abutments could be <br />fulfilled. This assumption is based on the projection of test-hole <br />data from the four test holes shown on Figure 2, and in Cross <br />Sections in Figures 3 and 4. <br />4.4 Topsoil Stockpile Areas <br />Eight (A-H) topsoil stockpile areas have been designated <br />• within the vicinity of the mine. Locations of stockpile areas had <br />27 <br />