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<br />Reporting Period Lune 23, 1997 -July 3, 1997, <br />2 <br />Sylvester Gulch Main Road: Groundwater seepage in the pioneered Main Road from <br />Station 61+50 to 72+00 is continuing. Water is being controlled with a surface ditch at the <br />toe of the cut. Cut slopes have been flattened to 2:1 and appear stable. Fill slopes are being <br />brought up in lifts at 1.5:1, compaction is meeting specifications and fill slopes appear stable. <br />The Main Road alignment along the north slope of the shaft site azea (Station 85+00 to end) <br />remains dry and stable. The fill slope from Station 54 to 57 is being brought up at 2:1 and <br />appears stable. <br />Landing #2 Road: Pioneered light-use road to Landing #2 through Station 47+00 remains <br />stable. Completion of the pioneered road along a redesigned alignment which avoids blasting <br />through rock bluffs will be completed next week. <br />Dewaterinp Borehole Road: Three sight lines (upper, middle, lower) were established <br />between Stations 15+00 and 19+00 on June 26. Upper and lower sight lines show no <br />movement since installed. Middle section may be bulging slightly. Seepage associated with <br />sandstone strata along this road has slowed significantly, but is continuing. MCC will <br />continue to monitor these slopes. <br />Substation: Cutting of the slope began on June 24 with excavation of a bench at the top <br />limit of the cut. Sight lines were established at the top of the cut slope on June 27. On June <br />29, with the bench highwall at approximately 15 feet, a dozer operator noticed cracking above <br />the highwall and ceased operations. When inspected on June 30 and again on July 1 with a <br />geotechnical consultant from Golder Associates, multiple 1' wide cracks in the cut slope above <br />the highwall were observed paralleling the contours. Additional smaller cracks were also <br />observed in the undisturbed ground above the top of the cut slope. These cracks were <br />relatively shallow (4-6') and limited to the center portion of the cut slope. Both east and west <br />ends of the substation cut were unaffected and remain stable. No springs or soft ground was <br />observed. The Contractor was directed to strip additional area above the top of cut so as to <br />flatten the cut slope to 2:1 within the cracked area. The cracked areas were excavated to the <br />new slope, and additional cracking has not occurred as of July 3. Of note, over excavation of <br />the area of worst cracking uncovered a large (25' wide by 20' high) boulder, and it appears the <br />worst cracking was probably the result of loose soil peeling off from in front of it as the <br />highwall excavation removed downslope soil. MCC will continue to monitor this slope. <br />Data Collection <br />No additional data was received. Laboratory analysis of soils collected at Geotechnical Holes <br />#97-7, 12, 13, 14, and 15 aze still in progress. Additional drilling for locations #97-2 <br />(inclinometer and piezometer) and #97-3 (piezometer only) are scheduled for July 6 and 7. <br />