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.i ~~ Reporting Period September 2, 1997 -September 7, 1997. Main Crossing (Wall F-1 and F-2) In Progress Complete 9/19 Wall G Begin 8/20 Complete 9/19 Pond SG-1 and Culvert CCW-1B In Progress Complete 9/15 Wall H Begin 8/22 Complete 9/12 Water Tank Extension Indefinite Hold Lower Sylvester Gulch Road Begin 8/27 Complete 10/3 Field Observations, Data Collection, and Ongoing Evaluations 2 A complete inspection was performed by MCC on September 5, 1997 and September 7, 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: Clearing and topsoil stripping was completed on approximately 80% of the lower Sylvester Gulch Road. Observation of the cleared slopes showed no failures or slumping on September 5 or September 7, and no previously undiscovered springs were exposed. Removal of the heavy underbrush has allowed MCC to better evaluate water and slope conditions, and finalize the design features of this road. The finalized design includes: installation of five additional culverts under the road in the locations of natural drainage paths; benched cut slopes from Station 17 to 19+50 and Station 25+50 to 33 which will also incorporate French drains into the bench design; addition of a Clearwater diversion ditch at the top of a smooth cut slope from Station 21+60 to 25+50; and extension of the road ditch French drain approximately 400 feet to Station 34. As built drawings of the final road configuration will be forwarded to CDMG when the road is completed, as MCC expects some changes in the road alignment, cut slopes, and drainage will occur as construction progresses. UoDer Sylvester Gulch Road: No failures, movement, or new cracking was observed at the failed fill area (Station 62 to 68) on September 5 or September 8. All other pioneered sections of the main road appeared stable, including both approaches to the main crossing (F- walls). Inclinometer I-12 has ceased providing useful information at the failed fill area and was abandoned in order to allow the contractor to remove the remaining fill material from this slope. Surface surveys continue to indicate no appreciable movement either above the cut slope or below the fill area. Analysis, evaluation, and potential redesign of this section of road continue to be worked on by Golder Associates and Barr Engineering. As reported previously, 3 test pits were excavated at and below the toe of the failed slopes, within previously disturbed areas. The location of each test pit is noted on the test pit log sent with last weeks report. Each test pit was approximately 5 CY, and was back-filled immediately upon completion. MCC does not expect to complete redesign in time to allow the road to be rebuilt during this construction season. MCC plans to either reclaim the current disturbance prior to winter, or submit a minor revision to leave an at-grade light-use road in place.