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Reporting Period November 1 I, 1997 -November 18, 1997 Field Observations, Data Collection, and Ongoing Evaluations 2 A complete inspection was performed by MCC on November l8, 1997 to visually observe and evaluate the stability of slopes within the project area. Data collection efforts continue and evaluation or recvaluation of specific areas of concern is being performed as needed. individual areas are discussed in detail in the following sections. Supporting documentation is attached for your review. Lower Sylvester Gulch Road: Final installation of culverts and road ditch french drains are in progress. The topof--slope french drains described in previous reports appear to working effectively. Slopes below the drains are remaining stable, with the exception of some minor sloughing. Inclinometer 1-2 is no longer readable. The probe was unable to pass the shear zone at approximately 30 feet below ground surface. The benched slopes below i-2 were inspected daily and no movement, cracking, or slumping was observed, although some minor seepage is evident. The french drain in this area continues to flow at a moderate rate. A replacement inclinometer for this slope is planned, and will be installed when access and weather allow. Visual monitoring of this slope will continue. As reported last week, inclinometer I-4B is also unreadable. A replacement inclinometer at this location is also planned, horizontal drains in hvo locations north of 1-4B are being considered, and a 600 foot long rock buttress is partially complete for this slope. Inspection of the slopes above I-48 does not indicate significant new movement. Slopes below I-4B were inspected daily, and no movement, cracking, or slumping was observed, although some minor seepage and bench sloughage continues to occur approximately 200 feet north of I-4B. Observations of these slopes will continue. Upper Sylvester Gulch Road: No stability issues to report. Main Embankment (F-Wallsl: Weekly measurement at I-9 and I-10 were taken on November l3. Velocities decreased in both inclinometers. The reading on I-9 was highly suspect, however, since the probe became partially stuck at the shear zone approximately 35 feet below ground surface. Further monitoring of 1-9 will not be attempted. Replacement of I-9 is planned, but is dependent on weather and drill rig access. Pore pressures continue to remain stable, although piezometer VW-3 now reads zero, indicating the probe or cable has been damaged. MCC will continue to monitor the inclinometers and piezometers. DewaterinQ Borehole Road: Minor water seepage continues on the east side cut slope as reported previously. Survey monuments installed above the cut slope and french drain continue to show a very minor northward creep. To control potential erosion, and to provide some buttressing for this slope, 12" rip rap is being placed in the seepage areas. Monitoring will continue. Substation Sloae: Visual observations and survey data for the slope above the substation indicates surface movement is continuing at a slow and gradual pace, with incremental movements decreasing over time. No advancement of the head scarp further upslope and into the Landing #2 road was observed. The completed mid-slope french drain appears to be functioning effectively. The midslope inclinometer (Inclinometer I-26) indicates the velocity of movement at approximately 20 feet below ground surface is also decreasing. The first comparative survey of the inclinometer placed in the Landing #2 Road (directly above the slide area) shows no movement. MCC will continue to monitor this slope.