REP23816 - Laserfiche WebLink

Home Browse Search

Station 15 Station 15 was established for the 1991 surveying year. Station 15 overlies • approximately 700 feet of overburden and is located within the 600 - 800 foot overburden depth Stevens Gulch alluvium protective buffer zone. Panel B was retreat mined with partial floor extraction during May, 1992 in the immediate vicinity of station 15. The 2001 survey results show an elevation gain of 0.13 feet when compazed to the December 2000 elevation. Station 16 Station 16 overlies approximately 950 feet of overburden. Surveys at station 16 were initiated in August, 1982 and continued biannually through 1984. Annual surveys occurred in 1992 - 1994. The 1st North - 3 West panel adjacent to and east of station 16 was retreat mined in October 1981. Panel A, located beneath station 16 was retreat mined in July and August, 1991. The 2001 survey data indicates a 0.39 ft. elevation gain at this site when compazed to readings taken in June of 2000. Station 16 is located within a mapped landslide azea as well and some minor coordinate variability has been recorded. Station DH55 Drill hole 55 is located over Panel Z with approximately 1750 feet of cover. Panel Z was retreated mined in the vicinity of DH 55 in July 1994. The collaz elevation of DH 55 was originally established in 1981 at 8578.57 feet. The monitoring point established at this site was surveyed in January 1994 at elevation 8543.11 (-35.46 feet). An appazent error in survey elevation data exists for this site. The October 1994 survey indicates a minor (0.07 foot) gain in elevation compazed to the • January 1994 survey. The 2001 survey indicates a gain of 0.85 feet when compared to the June 2000 elevation. Station DH65 Drill hole 65 is located over the I East Main in the west thick coal pod with approximately 1380 feet of cover. In May 1994 the I East Mains were advanced under DH 65. During 1995 retreat mining occurred both north and south of DH 65. The October 1994 survey indicates a minor (0.13 foot) gain in elevation compazed to the January 1994 survey. The 2001 survey performed by Cragg Surveying shows a increase of 0.42 feet in elevation when compazed to the June 2000 elevation. Station DH66 Drill hole 66 is located over Panel ZZ- I North in the west thick coal pod with approximately 1290 feet of cover. Advance mining occurred under DH 66 during May 1995 and retreat mining occurred during July or August 1995. The collaz elevation of DH 66 was originally established in 1982 at 8209.89 feet. The monitoring point established at this site was surveyed in January 1994 at elevation 8189.50 (-20.39 feet). An apparent error in survey elevation data exists for this site. The October 1994 survey indicates a,minor (0.07 foot) gain in elevation compared to the January 1994 survey. The 2001 survey performed by Cragg Surveying shows an increase in elevation of 0.74 feet when compared to the June 2000 elevation. -2-