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<br />Reporting Period June 8, 1997 -lunc ?2, 1997 <br />2 <br />Sylvester Gulch Main Road: Groundwater seepage and localized slumping of cut faces in <br />the pioneered Main Road from Station 61+50 to 72+00 is continuing. Additional clearing has <br />been conducted, but no other road work in this area. Cleared ground is slightly hummocky. <br />Natural slopes, and design cut and fill slopes in this section are 1.5:1 or steeper. MCC is <br />considering flattening these slopes to 2:l or 2.5:1 to improve stability. The Main Road <br />alignment along the north slope of the shaft site area (Station 85+00 to end) was pioneered on <br />June 11 and June 12, and inspected on June 13. Cut slopes are stable and no water <br />encountered <br />Landing #2 Road: Pioneered fight-use road to Landing #2 inspected on June 14 and June <br />19. No water encountered. Cut slopes standing nearly vertical and appear stable. From <br />Station 45+00 to Station 51+00 the current alignment would require extensive blasting, so a <br />redesign of this road is being implemented. Redesigned alignment will stay below the rock <br />bluffs (and above slide area C-6) and contour into Landing #2. Anew section of light-use <br />road, running southward approximately 1000 feet at a flat grade, will be necessary at the top <br />of the rock bluffs to access power pole locations. <br />Dewatering Borehole Road: Minor, localized slumping of the cut slope in various locations <br />between Station 16+00 and 18+00 was noted on June 14, and is probably associated with the <br />wet weather the previous week. The lazgest slump measured 12' wide by 6' high, with <br />approximately 3' of downhill movement. Seepage associated with sandstone strata along this <br />road, as reported in the last report, has slowed significantly and slumping is not continuing. <br />Seepage from beneath the road fill at Station 15+00 has discontinued, and the fill slope is dry <br />and stable. An attempt to install a French drain at this location was unsuccessful because the <br />trench excavation at the inside edge of road encountered no water to a depth of 8 feet before <br />hitting solid sandstone. MCC will continue to monitor these slopes. <br />Substation. Topsoil stripping operations were completed for the substation and cut slope on <br />June 21 and the site was inspected on June 22. Some groundwater seepage observed on the <br />lower west end of the site, but none up slope. Sight lines will be established before <br />commencing excavation next week. <br />Data Collection <br />Results of the fourth inclinometer survey at Borehole #97-4 were received. Movement was less <br />than the previous biweekly reading, but continues at generally the same magnitude and direction. <br />A fifth inclinometer survey was conducted on June 18. <br />Laboratory analysis of soils collected at Geotechnical Holes #97-7, l2, 13, 14, and 15 are in <br />progress. Additional drilling has been postponed to approximately July 6, due to wet soil <br />conditions at locations #97-2 and #97-3, and access problems at other holes due to construction <br />activities. <br />