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<br />Reporting Period July 12, 1997 -July 20, 1997. <br />2 <br />Sylvester Gulch Main Road: Field investigation reports for the slope failure from Station <br />62+00 to 67+00 were received from both geotechnical consultants. The new inclinometer (I- <br />11) installed at the toe of the failed fill slope was monitored daily from July 14-16, and <br />indicates slip planes at approximately 4' - 6' and 12' - 16' below surface. Movement at 12' - <br />16' was approximately 2.25" in three days on a bearing almost due east. An attempt to obtain <br />a reading on Sunday, July 20, was unsuccessful (the probe would not go down) indicating <br />additional movement has closed the hole. Surface surveys do not indicate measurable (>0.1') <br />movement above the cut slope. <br />The results of the fifth inclinometer survey at Borehole 97-4 (approximately Station 30+00) <br />were received and movement continues at a slow but steady rate. Per MCC's slope stability <br />action plan, reevaluation of design slope stability at this site is in progress. The first bi-weekly <br />inclinometer survey for Borehole 97-2 (approximately Station 16+00) was also received, and <br />no obvious movement was detected. Monitoring will continue. The Main Road alignment <br />along the north slope of the shaft site area (Station 85+00 to end) remains dry and stable. <br />Landine #2 Road: The light-use road to Landing #2 was inspected on July 17 and July 20. <br />Soil cut slopes are dry and appear stable. Rock cuts blasted out of sandstone outcrops appear <br />solid and competent. <br />Dewatering Borehole Road: The three sight lines (upper, middle, lower) between Stations <br />15+00 and 19+00 were observed on July 16 and July 20. The minor movement of the sight <br />lines previously reported does not appear to be increasing. Minor seepage associated with <br />sandstone strata along this road is continuing. MCC will continue to monitor these slopes. <br />Substation: Daily visual observation of the failed slope above the substation appears to <br />show no major additional movement in the slumped area and no advancement of the head <br />scarp below the Landing #2 road. Survey data shows no movement on the lower site, but <br />does indicate minor (0.15') movement above the Landing #2 road. Material from the grading <br />of the Landing #2 road was pushed into the head scarp crack. The scarp has not reappeared. <br />Golder Associates is evaluating methods to stabilize the current head scarp, if needed. MCC <br />will continue to monitor this slope. <br />Shaft Site #1 and #2: Clearing and excavation of the heavily timbered cut slope to the <br />south of the shafts was completed and cut slopes appear stable with no water observed. Per <br />MCC's slope stability action plan, reevaluation of the stability of the cut slope above the intake <br />shaft is in progress. At the southwest comer of the site (start of the Electric Borehole road) <br />five distinct springs flowing approximately 5-15 GPM each were uncovered. French drains <br />have been designed for this site and will be installed the week of July 21. <br />