Laserfiche WebLink
West Elk PR-07 Response to Adequacy Comments <br />page 2 <br />contractor's drawings for the construction of the proposed facilities. A reduced version of this <br />RFP package was submitted in duplicate, apparently for inclusion in the record. <br />As detailed here below, MCC's response provides insufficient additional technical information <br />to warrant the Division amending it's earlier adequacy opinion. The RFP package does <br />assist by providing more detail regarding Golder Associates proposed design treatments for <br />some of the slope stabilization challenges identified at the SGFA site. <br />While minor differences of interpretive opinion exist within the various geotechnical reports <br />submitted for the Division's information by MCC, the authors generally agree that Sylvester <br />Gulch is subject to wide spread slope instability problems and that care should be exercised <br />in developing the proposed Sylvester Gulch facilities. Further, every consultant, including <br />Golder Associates, recommends that additional reconnaissance, monitoring, or site specific <br />investigations be conducted in order to complete final design of the various surface facilities. <br />Excerpts from reports submitted for the Division's consideration. <br />"Slope Stability Assessment Sylvester Gulch" by Envirocon, Inc. - 9/93 & 10/94 <br />Envirocon completed a reconnaissance mapping and included a "Sylvester <br />Gulch Risk Assessment" Map in their report. They delineated areas they <br />believed to be subject to "low risk", "medium risk" and "high risk". They <br />included general recommendations for development of facilities within each of <br />these risk zones. Within medium risk zones they recommended; "Any <br />construction activities in this area should be safe-guarded with adequate <br />drainage, retaining wall buttressing, and monitoring to assure minimal slope <br />creep". Within high risk zones they concluded; "Area not safe for construction <br />and should be monitored for movement. Preventive action advised for this <br />area, such as improved drainage, additional buttressing, and additional <br />vegetative cove". Envirocon's risk map included areas immediately upslope <br />from the power substation bench, and immediately upslope from a significant <br />portion of the lower access road within the high risk zone. The map also <br />delineated the slopes immediately surrounding the shaft bench area, the <br />proposed location of the electrical substation, and the majority of the remainder <br />of the slopes immediately upslope from the access road within the medium risk <br />zone. The majority of the light access road alignment along the proposed <br />powerline alignment was apparently not mapped by Envirocon, Inc. <br />"Geology Map" by IntraSearch - 11/94 <br />This aerial photographic reconnaissance geology map of the SGFA is referenced by <br />