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i Reporting Period October 28, 1997 -November 3, 1997 Field Observations, Data Collection, and Ongoing Evaluations 2 A complete inspection was performed by MCC on November 3, 1997 to visually observe and evaluate the stability of slopes within the project area. Data collection efforts and evaluation or re-evaluation of specific areas of concern continues. Individual areas are discussed in detail in the following sections. Supporting documentation is attached for your review. Lower Sylvester Gulch Road: Excavation of cut slopes and benches along the alignment of the Lower Sylvester Gulch road remain at approximately 98% complete. Final completion is pending culvert and road ditch french drain installations, which are in progress. The top-0f--slope french drains described in previous reports appear to working effectively th that water is being captured at all locations where installed and slopes below the drains are remaining stable, with the exception of some minor sloughing. Inclinometer I-2 was read on October 29. The movement reported last week at 24' to 32' depth is continues. The benched slopes below i-2 were inspected on October 30 and November 3 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 water level 13' below surface was measured in the piezometer adjacent to 1-2. Golder Associates is working on new stability analyses of the current slope geometry using back calculated strength values and known groundwater elevations. Inclinometer 1-2 ++~II continue to be monitored. The first comparative survey of new inclinometer I-4B was taken on October 29. A relatively large deflection was noted between 19' and 27' below ground surface. Slopes above and below I-4B were inspected on October 30 and November 3 were dry, and no movement, cracking, or slumping was observed. Some minor seepage and bench sloughage was noted approximately 200' north of I-4B. Golder Associates ++~II prepare new stability analyses for this area, as well. Based on the movement we are seeing at I-2 and 1-4B, MCC is inspecting the slopes below these inclinometers on a daily basis and is shortening the time period between inclinometer readings. Upper Sylvester Gulch Road: As reported last week, weekly monitoring of survey monuments above and below the failed fill area have been discontinued. Anew monitoring program may be initiated after reclamation. Nevv inclinometer I-13, installed at the top of the ridge above the failed area, shows some surface movement, but no movement at depth. Main Embankment (F-Walls): Weekly measurement at I-9 and 1-10 were taken on October 30. 1- 10 appears to have stabilized and is not moving. A small increase in velocity at I-9 was detected, but is less than half the velocities measured in September. Pore pressures also continue to decrease. MCC will continue to monitor the inclinometers and piezometers. Landin¢ #2 Road: The light-use road to Landing #2 was inspected on November 3. Soil cut and fill slopes appeared stable throughout the length of the road and hydroseeding of these slopes is in progress. Drainage ditches and berms are in place and functional.