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<br />Reporting Period August 18, 1997 -August 29, 1997 <br />3 <br />completed, as we expect the road alignment, cut slopes, and drainage to change as <br />construction progresses. <br />Upper Sylvester Gulch Road: No failures, movement, or new cracking was observed at <br />the failed fill azea (Sta 62 to 68) on 8/20 or 8/25. All other pioneered sections of the main <br />road appeared stable, including both approaches to the main crossing (F-walls). Monitoring <br />of inclinometer I-12 at the failed fill area continues to show small movements at <br />approximately 6' to 10' below ground surface (BGS). Surface surveys continue to indicate <br />no appreciable movement either above the cut slope or below the fill area. Three test pits <br />below and north of the toe of [he failure azea were dug on 8/21. Test pits were logged by <br />Golder and videoed by MCC. Notable observations in Test Pit #1 were the presence of water <br />and the same 6" thick soft, saturated clay layer noted in the I-11 Shelby tube opened last <br />week. No notable observations were made in Test Pit #2. In Test Pit #3, a large (10' deep) <br />coal pocket was encountered, with water below the coal but not in it. As previously <br />discussed with CDMG staff, MCC does not plan to re-design and reconstruct this road <br />section until a thorough evaluation of the failure is completed and long term stability can be <br />assured. Analysis and evaluation aze ongoing, however, MCC does not expect to complete <br />this work in time [o allow the road to be rebuilt during this construction season. At this time, <br />MCC plans to either reclaim the current disturbance prior to winter, or submit a minor <br />revision to leave an at-grade light use road in place. <br />Main Embankment (F-Wallsl: Approximately 20 feet of fill was placed from 8/18 through <br />8/29. Pore pressures did not change from 8/18 through 8/25, but increased slightly <br />(approximately 1 foot of head) from 8/25 to 8/28. Settlement of the multiplate and <br />foundation under the embankment is occurring, but was expected. Total differential <br />settlement in the middle of the embankment was measured at 8" on 8/24, or approximately <br />30% of [he maximum allowable by design. Inclinometer I-10 at the south toe of the <br />embankment, and inclinometer I-9 at the north toe of the embankment both showed very <br />slight movement in readings taken 8/24 and 8/25, however, no distinct planes of movement <br />are evident and movement was uphill and westward, or exactly opposite the direction <br />expected. Monitoring will continue. <br />Landine #2 Road: The light-use road to Landing #2 was inspected on 8/25. Soil cut and <br />fill slopes appeared stable throughout the length of the road. Transmission line pole <br />structures adjacent to the road were completed on 8/28. <br />Dewaterin~ Borehole Road: The sight lines and slope conditions remain as previously <br />reported. Minor seepage and associated slumping is continuing. Remediation of the seepage <br />and slumping on this slope will be addressed during conversion of this road to a 24 foot wide <br />haul road. CDMG is in receipt of a minor revision (MR #224) for this work which <br />incorporates french drains at the top and bottom of the new, regraded cut slopes. <br />