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f <br />Reporting Period September 22, 1997 -September 29, 1997 <br />Field Observations, Data Collection, and Ongoing Evaluations <br />A complete inspection was performed by MCC on September 29, 1997 to visually observe and evaluate the <br />stability of slopes within the project area. Data collection efforts and evaluation or re-evaluation of <br />specific areas of concern continues. Individual areas are discussed in detail th the following sections. <br />Supporting documentation is attached for your review. <br />Lower Svlvester Gulch Road: Excavation work is 95% complete between Stations 37 and 50, and <br />fill operations in this section are in progress. French drains were completed at the top of the slopes <br />between Stations 25+50 and 33+00. Seven layers of geogrid at MSE Wall E (Station 50+50 to 54) <br />were completed. All slopes between Station 25+50 and 54 (including benched slopes and the locations <br />of French drains) are dry and stable. <br />Between Station 19 and 23 (a former wetland location) numerous seeps have appeared in the top-0f-- <br />slope cut bank which are being caught by the previously installed top-0f--slope V-ditch. There appears <br />to be much more near-surface water on this slope than previously anticipated, and it is apparent that <br />the installed V-ditch will be inadequate to control these flows over the long term. As a result, MCC <br />has decided to replace the V-ditch with a combination trapezoidal ditch and French drain. Construction <br />of this ditch/French drain is underway and will be completed before additional excavation on this slope <br />is performed. Except for the typical mud slumps at seep locations, this slope remains stable both <br />above the cut bank and below the ditch. <br />The latest reading on inclinometer I-2 (on September 25) shows no changes in magnitude or direction <br />from what was previously observed and reported. Inclinometer I-2 will be maintained and monitored <br />during construction and for the long term. <br />Upper Svlvester Gulch Road: The residual failure at approximately Station 63+50 reported two <br />weeks ago remains stable after regrading. Surface surveys continue to indicate no appreciable <br />movement either above the cut slope or below the fill area. Stability analyses and other evaluations of <br />the failed fill azea by Golder Associates and Barr Engineering are due this week. <br />Main Embankment (F-Walls): As reported previously, construction of the F-Walls was finished <br />out at a lower elevation due to concerns over small, but increasing movements at depth observed in <br />inclinometer 1-9 and 1-10 on either side of the embankment. The embankment is now complete except <br />for final base course and guardrail. The weekly measurements at I-9 and i-]0 taken on September 25 <br />show continued incremental increases in cumulative movement in the same directions as previously <br />reported. However, foundation settlement has stopped, and pore pressures are stable or decreasing. <br />MCC will wntinue to monitor the inclinometers and piezometers. <br />Landing #2 Road: The light-use road to Landing #2 was inspected on September 29. Soil cut and <br />fill slopes appeazed stable throughout the length of the road. Road base has been placed up to <br />approximately Station 40. Drainage ditches appeaz to be working properly. <br />DewaterinR Borehole Road: The sight lines and slope conditions remain as previously reported. <br />Minor seepage and associated slumping continues. <br />