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Reporting Period September 8, 1997 -September 15, 1997 <br />3 <br />appreciable movement either above the cut slope or below the fill area. As reported <br />previously, analysis, evaluation, and potential redesign of this section of road continues to be <br />worked on by Golder Associates and Barr Engineering. <br />Main Embankment (F-Walls): Approximately 8 feet of fill was placed from September 8 <br />through September 15. Pore pressures (measured approximately 30 feet below foundation <br />level) have been rising gradually on both sides of the multiplate since August 28. No sharp <br />rises in pore pressure were monitored. Settlement of the multiplate and foundation in the <br />middle of the embankment was measured at 1.2 ft. on September 15, or approximately 60% of <br />the maximum allowable by design. Measurements taken at inclinometer I-9 on September 12 <br />showed a sharp increase in incremental displacement at 28 ft to 38 ft below ground surface, as <br />well as an increase in velocity, although cumulative movement away from the embankment <br />remains small (0.5 inch). As a precautionary measure, work on the F-Walls was halted for the <br />weekend pending additional monitoring on Monday, September 15. The September 5 reading <br />showed an additional 0.1 inch movement and increased velocity away from the embankment. <br />Conversely, measurements taken at inclinometer I-10 on September 12 and September 15 <br />show a slight uniform bulging (also away from the embankment) but with no sharp peaks in <br />incremental displacement or velocity. We believe this is indicative of normal settlement and <br />local redistribution of soil stresses within the vicinity of the embankment rather than a large <br />scale mass movement of the underlying foundation material. Work on the F-Walls will remain <br />on hold, and additional inclinometer readings will be taken on Wednesday September 17. <br />Landing #2 Road: The light-use road to Landing #2 was inspected on September 13. Soil <br />cut and fill slopes appeared stable throughout the length of the road. Final drainage ditches <br />are being established. <br />Dewaterinr~ Borehole Road: The sight lines and slope conditions remain as previously <br />reported. Minor seepage and associated slumping continues. Remediation of the seepage and <br />slumping on this slope will be addressed during re-construction of this road to a 24 foot wide <br />haul road, per Minor Revision (MR) 224. Also, per MR 224, sight lines will be established on <br />this slope to monitor the stability of the as-built configuration. Work on this road is planned <br />to begin in approximately two weeks. <br />Substation: Visual observation of the slope above the substation on September 13 and <br />September 15 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 13 and indicate approximately 1/8 <br />to 1/4 inch of additional downslope movement since September 7. Survey data confirms <br />movement has slowed at stations SL-3, SL-4, and SL-5 after completion of the rock filled <br />ditch. Monitoring will continue. <br />