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Cyprus orchard Valley Coal Corporation ca~leted advance development and pillar • extraction of Panel A+, advance development, partial floor, and full pillar extraction of Panel B, advance development of Panel C, and the continued advance development of the western II West Sutmains (32 crosscuts) in 1992. Subsidence survey monitoring of selected wide-spaced monuments in the vicinity of active mine workings was conducted during September of 1992. Surveying of these selec,-ted stations was conducted in accror<iance with the projected monitoring addressed in the 1991 Annual Subsidence Report with the exception that stations 94 and 96 were not monitored. Station 95 was monitored in conjunction with a land survey used to establish section corner and lease boundary locations. Selected subsidence monitoring stations established over the Pitkin Mesa Pipeline were monitored in January arcs September, 1992. A visual walkover inspection of recently pillared areas (Panels A and A+) was conducted in wnjunction with subsidence monitoring in the area during September, 1992. Wide-Spaced Monitoring Grid Station Summary Eight wide-spaced monitoring grid stations were surveyed for the 1992 reporting year. Stations 6, 7, 8, 14, 15, 16, 88, and 95 as depicted on Map No. 2-5 were surveyed. The following discussions present a station by station assessment of survey results generated for 1992. Monitoring station data sheets are appended to this report for reference. Station 6: Surveys were initiated in August 1982 and continued biannually through July 1984. Surveys were reinitiated in 1987 and conducted annually through 1992. Station 6 is located on • approximately 350 feet of overburden and lies approximately ~~,y 300 feet north of the 1st North, 2 1/2 West panel retreat I _.,,(1.1 mined from May through June, 1983. Station 6 lies adjacent to ~,JIS~ s'' the II West Submain development advanced in 1987. 1992 survey data indicates an elevation gain of 0.34 feet, within the previously established normal range of measurement docwnented at this site. Station 7: Surveys were initiated in August 1982 and continued biannually through July 1984. Surveys were conducted again in November, 1987, January, 1992, and September 1992. Station 7 overlies approximately 750 feet of overburden. The station showed no I~ sly consistent indication of subsidence effects through 1987. ~ ~ 1992 survey results show an elevation gain of 0.28 feet evident since the last survey (January 1992). Reference to Permit No. C-81-038, Map No. 2-2 shows that station 7 lies in the general vicinity of a large mapped landslide area. An evident change in northing and Basting coordinate positions may be indicative of natural landslide movement resulting in surficial material movement. The II West 5~lanains were advanced in the vicinity of station 7 during October, 1990. The 1st North, 2 1/2 West area approximately 300 feet south of station 7 was retreat mined from May through June, 1983. Mining activity took place north of station 7 during 1992 in Panel B. • Station 8: Surveys were initiated in Auqust 1982 and continued biannually