Laserfiche WebLink
APR.-I'~951MUN1 15:a0 W'RIGHT WATER TEL:~03 a80 IU?0 P.OU2 <br />RECEIVEp gy Fa y <br />PRIVILEGED <br />AND CONFIDENTIAL <br />MEMORANDUM <br />TO. M~. Kathy Welt, Mountain Coal Company <br />FROM: Jvl;rr Road, Cottsultaat, Wright Water Engineers <br />DATE: April 17, ] 995 <br />AFR 1 7 1985 <br />RE: Subsidence Crack in the Lone Pine Area at West Elk Mine <br />The following memorandum, as per your request, is for a suggested response to the March <br />8, 1995 Icttcr from Ms. Christine E. Johnston of the Office of Mined Land Reclamation vi <br />of the Colorado Division of Minerals and Geology (CDMG). W <br />w <br />2 <br />I accompanied Ms. Johnston of the CDMG and Mr. Norm Every of Mountain Coal V <br />Company (MCC) to inspect the subject crack at West Elk Mine on September 27, 1994. Z <br />'i'bis memo relies on that visit, a review of field notes and photos taken at that time, and ~++ <br />reports of Mr. Norm Every's revisit to the crack on March 2?., 1995. The described crack uce,+. <br />occurs near the midpoi~ of the south line. of Section 17, T135, R90W on a high spur t <br />ridge approximately i001feet topographically above and north of the meadow end the old .2 <br />cabin remnants at the forks of Lone Pine Gulch. The described crack is the largest <br />(widest) of a linear family of smaller cracks which extend easbwest discantinuotuly for <br />approximately ] 50 feet. IThe cracks partially aoss the spur ridge between two prominent l7 <br />cliff forming sendstones,~opographicelly and atratigraphically above and below the crack, 3 <br />The description of the c ck as being "S fcet wide, 50 feet long and 30 feet deep" taken I <br />at face value would be~atming. AI fuller description of the crack puts it in a truer <br />perspective. <br />The 5-foot width pertains to t}tc maximtun width oP the crack. Only a <br />short portion (10~ Jto 15 feet) o that creek extent was 5 feet wido, Much <br />of the crack widest was only 6 to 1 B inches wide. <br />The 30-foot depth of the crack was reported by MCC surveyors who <br />reportedly were able to extend a tape that far down along a portion of the <br />creek. Last fall when we visited the crack, a small portion of the crack <br />(approximately 12 to 18 inches in diameter) in the western corner of the <br />widest part of the crack, was the only portion of the crack more than 2 to <br />5 feet deep. That deep portion of the crack looked almost like a vertical <br />