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I. SURVEY DATA • The coordinate locations of subsidence monuments that are currently being monitored are tabulated in Appendix A. First quarter monitoring was not performed because of inaccessible monuments. II. MAPS A. Plan View The attached map (drawing FC-14-8601) shows a plan view of the existing underground workings (updated to January 1, 1988), future mining projections, surface topography and structures, and subsidence monument locations. B. Cross Section The attached cross section (drawing FC-14-8402) shows the three monuments installed in the location of Foidel Creek. These monuments are designated FC-2, FC-3, and FC-4. The attached cross section (drawing FC-14-8602) shows the surface subsidence monuments installed to monitor surface movement associated with underground mining of 1st Panel South. Note that this cross section map is drawn showing each monument elevation referenced at ground level equals zero. This allows a more useful vertical scale to be used which will better illustrate the relative subsidence. These monuments are designated SM-7 through SM-24 (transverse section), • and SM-19, SM-25 through SM-41 (longitudinal section). Underground mining continued to progress beneath some of these monuments in January, June, and July, 1987, while no mining occurred from February through May, and August through December, 1987. No cross sections are included for the spoils stability monuments because only one monument is installed along the slope dip at each location. These monuments are designated SP-2, SP-3, and SP-4. III. HYDROLOGY The underground mine is dewatering the adjacent Wadge overburden aquifer. Water monitoring data will be included in the annual hydrology report. IV. STRUCTURES Coal production has occurzed in 1st Main North, 1st Panel South, 1st Headgate West, and 1st Tailgate West. In 1st Panel South, partial extraction of pillars continued through January, 1987, and discontinued from February through May, 1987; partial and full pillar extraction resumed again in June, and July, 1987. Several surface structures associated with the underground section of 1st Panel South have been surveyed. These structures are shown on drawing FC-14-8601 and include two buried water tanks, CYCC office • building, and a gas storage tank. Also, monitoring of the CYCC training building began in March, 1987, and monitoring of two new buried water tank locations began in December, 1987, and will be monitored on a quarterly basis.