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Anomalous Conditions: Small seeps fran both roof aryl floor sources were <br />• encountered in the first four crosscuts. <br />II West Submains• <br />Mined Length: 1400 feet of submain advance development west of South III <br />Submains. <br />Mining Height: 8.5-9.5 feet. SubmalRC developed In upper' "D" seam only. <br />Roof: Comprised of muddtones and sandstones with a high conoPS~tration of pots <br />and slickensides. Roof coal was not left in place. Develoiaoent was <br />meshed on roof thnxx>h entire section to ensure roof stability. <br />Ribs: Rib sloughage was minimal with ribs standing well. <br />Floor: Interburtien between upper and lower "D" seams was used as floor and <br />provided oon~etent conditions. <br />Anomalous Conditions: [Jpper "D" coal seam tended to thin with westwani <br />development; roof instability required steel mesh <br />installationthrax~routdevelopmPnt. Development advanced <br />under dry conditions. <br />• Subsidence Impacts 1991 <br />Cyprus Orchard Valley Coal Corporation crng~leted advance development and pillar <br />extraction of Panel A, the initial advance development of Panel B (4 crosscuts), <br />and initiated the western II West SUbmain Development (11 crosscuts) in 1991. <br />Subsidence survey monitoring of selected wide-spaced mornmients in the vicinity <br />of active mine workings was conducted during January of 1992. Surveying of these <br />selected stations was conducted in accordance the proposal included in technical <br />revision 16, approved by CMLRD in February, 1992. A visual walkover inspection <br />of recently pillared areas (Panels H aryl G) was conducted in May, 1991. <br />Wide-Spaced Monitoring Grid Station Surtunary <br />Six wide-spaced monitoring grid stations were surveyed for the 1991 reporting <br />year. Stations 6, 7, 14, 15, 16, and 88 as depicted on Map No. 2-5 were <br />surveyed. 'Ihe following discussions present a station by station accacGrrw.,t of <br />survey results generated for 1991. Monitoring station data sheets are apperxled <br />to this report for reference. <br />Station 6: Surveys were initiated in August 1982 aryl continued biannually <br />through July 1984. Surveys were reinitiated in 1987 and <br />conducted annually throtrc~ 1991. Station 6 is located on <br />approximately 350 feet of overburden and lies approximately <br />300 feet north of the 1st North, 2 1/2 West panel retreat <br />. mined from May through June, 1983. Station 6 lies adjacent to <br />the II West Submain development advanced in 1987. 1991 survey <br />data indicates an elevation loss of 0.10 feet, within the <br />2 <br />