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<br /> <br />Reporting Period July 4, 1997 -July 1 1, 1997 <br />2 <br />geotechnical consultants were called in and investigated the site on July 7, July 8, and July 9. <br />All indications aze that the failure is a block-type failure of the foundation material underlying <br />the fill. Construction of this section of road has ceased pending additional monitoring and <br />investigations and redesign efforts. A detailed letter describing the scope and schedule of <br />short-term and long-term actions for this azea is being sent to you under separate cover. <br />The Main Road alignment along the north slope of the shaft site area (Station 85+00 to end) <br />remains dry and stable. The fill slope from Station 54 to 57 is completed to rough finish <br />grade. Fill slopes aze at 2:1 and appear stable. <br />Landing #2 Road: A pioneered light-use road to Landing #2 along a redesigned alignment <br />which avoids blasting through rock bluffs was completed, and rough grading is in progress. <br />Slopes are dry and appear stable. Numerous loose rocks and boulders are present which are <br />being removed as needed. <br />Dewatering Borehole Road: The three sight lines (upper, middle, lower) between Stations <br />15+00 and 19+00 were observed. The upper sight line shows no movement since installed. <br />The middle stake of the middle site line indicates a small (2") downwazd offset in the past <br />week. The lower sight line shows no offset but the middle stake may be showing a slight <br />bulge is occurring since the string line appeazs approximately 6" lower. Seepage associated <br />with sandstone strata along this road has slowed significantly, but is continuing. MCC will <br />continue to monitor these slopes. <br />Substation: The circular slope failure reported in the previous report reappeazed on Monday <br />July 7, with an additional triangulaz failure occurring above the circulaz section and below the <br />Landing #2 light use road. No movement or cracking was observed above the light use road <br />when inspected by MCC and a geotechnical consultant on July 8 and July 9. Observations <br />later in the week (from July 9-July 11) show no additional movement. Excavation work on <br />this slope is complete, therefore no immediate remedial activities for the central portion of this <br />failure are contemplated other than cleaning the slope of rocks. A method to stabilize the <br />current head of the slide, both above and below the Landing #2 road are being investigated. <br />MCC will continue to monitor this slope. <br />Shaft Site #1 and #2: The heavily timbered cut slope to the south of the shafts is currently <br />being cleared and partially excavated. Cut slopes appear stable and no water was observed. <br />Original Ground survey of this slope, received on July 10, indicates the actual ground <br />elevation is lower than indicated by the aerial photography. This means the cut required may <br />be substantially less than designed. <br />