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1994 Subsidence Report Page 4 indicated 0.31 feet were subsequently gained but again, new control point coozdinates were generated. No Honing activity took place in the vicinity of station 14 during 1994 prior to the subsidence survey. The May and September 1994 measurements were within the historic max;imim and mininnnn elevation values for this station. 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. September 1994 data indicates a minor (0.14 feet) elevation gain oonq~ared to October 1993 survey results. Station 16: Station 16 overlies approximately 950 feet of overburden. Surveys at station 16 were initiated in August, 1962 and continued bi-annually 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. 1994 survey data indicates a 0.74 feet • elevation loss at this site. Station 16 is located within a mapped landslide area as well and some minor coordinate variability has been recorded. Station DH 55: 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 collar 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 apparent error in survey elevation data exists for this site. The October 1994 survey indicates a minor ( 0.07 foot ) gain in elevation conq~ared to the January 1994 survey. Station DH 65: Drill hole 65 is located over the 1st East Main in the west thick coal pod with approximately 1380 feet of cover. In May 1994 the 1st East Mains were advanced under DH 65. The October 1994 survey indicates a minor ( 0.13 foot ) gain in elevation cca:g~ared to the January 1994 survey. Station DH 66: Drill hole 66 is located over Panel ZZ in the west thick coal pod with approximately 1290 feet of cover. No mining occurred in the vicinity of DH 66 during 1994. The collar 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