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• 2004 Production and Geologic Conditions The Bowie No. 1 Mine suspended operations during December, 1997 and remained idle throughout the 2004 calendar year. Operation Unit Descriptions Bowie No. 1 Mine has no operating units to report on during the 2004 calendaz year Subsidence Impacts - 2004 Subsidence survey monitoring of selected wide-spaced monuments in the vicinity of active mine workings was conducted during August and December, 2004. Surveying of these selected stations was conducted in accordance with the projected monitoring addressed in the 2003 Annual Subsidence Report. Selected subsidence monitoring stations established over the Pitkin Mesa pipeline were monitored also in August and December of 2004. Wide-Spaced Monitoring Grid Station Summary Thirteen wide-spaced monitoring grid stations were surveyed for the 2004 reporting yeaz. The station locations aze shown on Map No. 2-5. The following discussions present a station by station assessment of survey results generated for 2004. Monitoring station data sheets aze appended to this report for reference. Please note the change from historical stations to new GPS stations has created a change in all elevation reporting. This summary compazes only November 2001 through December 2004 for movement for the seven Pitkin Mesa Pipeline and November • 2001 to August or December 2004 for the wide spaces monitoring grid stations. Station 6 Surveys were initiated in August 1982 and continued biannually through July 1984. Surveys were re-initiated in 1987 and conducted annually through 1991 and biannually 1992 - 1994. Station 6 is located on approximately 350 feet of overburden and lies approximately 300 feet north of the 1st North, 2'/z West Panel retreat mined from May through June, 1983. Station 61ies adjacent to the II West Submain development advanced in 1987. The December 2004 survey data indicates a 0.05 foot increase in elevation when compazed to the November 2001 elevation. Station 6 is located within a mapped landslide azea. No mining anticipated to produce subsidence has occurred in the vicinity of Station 6 since 1983. Station 14 Station 14 is located in the Stevens Gulch alluvium protective buffer zone over approximately 750 feet of overburden. The station was initially surveyed in June, 1982. Subsequent surveys have been conducted annually since 1988. Panel G was advanced under this station in September, 1988. Retreat mining occurred outside the buffer zone in the vicinity of this site in February, 1989. Panel C was advanced adjacent to this site in December, 1992. An elevation adjustment of - 0.55 feet was detected at this site in October 1989 but was perhaps influenced by control station coordinates being redefined. January 1991 data indicated 0.31 feet were subsequently gained but again, new control point coordinates were