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Reporting Period September 2, 1997 -September 7, 1997, <br />3 <br />Main Embankment (F-Walls): Approximately 8 feet of fill was placed from September 2 <br />through September 6. Pore pressures (measured approximately 30 feet below foundation <br />level) have been rising gradually on both sides of the multiplate since August 28. A sharp rise <br />(7 feet of head) in pore pressure was monitored on September 3, but dissipated overnight. <br />Settlement of the multiplate and foundation in the middle of the embankment was measured at <br />12" on September 7, or approximately 50% of the maximum allowable by design. <br />Measurements taken at inclinometers I-9 and I-10 on September 5 both show cumulative <br />movement on the order of 0.15 inch away from the embankment at 28 ft to 38 ft below <br />ground surface, indicating some spreading of the underlying foundation is occurring. <br />Monitoring will continue. <br />Landing #2 Road: The light-use road to Landing #2 was inspected on September 7. Soil <br />cut and fill slopes appeared stable throughout the length of the road, except for some minor <br />cut slope slumping along the first 200 feet of road. This slumping is associated with active <br />springs that are saturating steep cut slopes (approximately 10 feet high) which are awaiting <br />final grading and ditching. The temporary road ditch remains open. <br />Dewatering Borehole Road: The sight lines and slope conditions remain as previously <br />reported. Minor seepage and associated slumping is continues. 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, per Minor Revision 224 (MR224). <br />Substation: Visual observation of the slope above the substation on September 5 and <br />September 7 indicates movement is continuing at a slow and gradual pace. No advancement <br />of the head scarp further upslope and into the Landing #2 road was observed. Survey stakes <br />placed across the head scarp were observed on September 7 and indicate approximately 1/4 to <br />1/2 inch of additional downslope movement since August 29. Survey data confirms additional <br />movement at station SL-3, SL-4, and SL-5. Filling of the midslope ditch across the scarp area <br />(as described in previous reports) was completed on September 4. Continued monitoring will <br />determine the effectiveness of this stabilization measure and whether additional measures are <br />needed. <br />Shaft Site #1 and #2: The compacted soil buttress installed to stabilize the shallow slope <br />failure on the steep cut slope south of Shaft #1 was observed on September 5 and September <br />7. The buttress appears solid and no new movement was visually detected. Slopes to either <br />side of the buttressed area were also observed and appeared stable. Site lines aze straight and <br />intact. Visual monitoring and collection of surface survey data will continue. <br />Electric Borehole Road: No additional springs have been encountered. Road cuts and fills <br />are dry and stable. H-Wall is approximately 50% complete. <br />