GENERAL55763 - Laserfiche WebLink

Home Browse Search

.~ Mountain Coal Company West Elk Mine Post Office Box 591 Somerset, Colorado 81434 Telephone 970 929-5015 Fax 970 929-5595 December 23, 1997 Michael P. Boulay Dr. lames Pendleton Colorado Division of Minerals & Geology Office of Mined Land Reclamation 13 13 Sherman Street, Room 215 Denver, CO 80203 ~II II~II~II~~~~~ II~ 999 R~CEIb~cD QFC ~ 1 199 pivioion of Minor?~it+ b MPHi4Gy Re: Geotechnical Report -Sylvester Gulch Site Development Ref: Permit Revision 07 and Technical Revision 79 to Permit No. C-80-007, West Elk Mine Dear Mr. Boulay and Dr. Pendleton: The following presents Mountain Coal Company's (MCC) final weekly summary of geotechnical issues for the Sylvester Gulch Site Development Project. The following information covers the time period from December 16, 1997 -December 23, 1997. As noted in last weeks report, MCC remains committed to a long term geotechnical monitoring program in Sylvester Gulch, and fully intends to continue to monitor slope conditions, surface survey monuments, and inclinometers on a regular basis. Information on these efforts will be forwarded to CDMG, as applicable, as part of future revision applications, or other corespondence. General Construction Summary and Schedule Construction efforts are essentially complete with the exception of punch list items. Completion of these remaining items will extend into January, with final demobilization expected about mid month. Field Observations, Data Collection, and Ongoing Evaluations A site inspection was performed by MCC on 12/22/97 and 12/23/97 to visually observe and evaluate the stability of slopes within the project area. Weekly surface surveys of the substation slope and dew•atering pad road slope were completed on 12/19/97 and 12!23/97. Inclinometer surveys were also performed at various locations. Individual areas are discussed in detail in the following sections. Supporting documentation is attached for your review. Lower Svlvester Gulch Road: Slopes are generally snow covered and frozen, making it difficult to inspect ground conditions. However, no "breaks" in the snow cover were observed which would indicate new sloughing. Minor ground water seepage appears to have stopped in conjunction with [he frozen ground conditions. Unoer Svlvester Gulch Road: The surficial slide on the steepened cut slope at approximately Station 76+00 reported previously continues to waste a small amount of earth into the roadside ditch. The slope is snow covered and frozen with no discernible cracking or active springs, and appears to have stabilized for the time being. MCC will continue to monitor this slope and will take appropriate actions to maintain the ditch and road should additional sloughage occur.