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:'fr Mountain Coal Company West Elk Mice Annual Subsidence Monitoring Repoli Year-end Report 1994 The mole current subsidence suety for the Went Elk Mme was performed in October 1994, by Measengw and Associates. The survey wen conducted using radial and level loop survey methods. The inatrumente used wwe a Wild, T-1, theodolite; aNikon-ND 20 distance meter; and an unspecified level. The following tables rofiect the northinga, castings, average pro-mining elevations, the previous report elevations (June, July, August 1994), the current survey elevations, subsidence dnce the Mid-year Semi-Annual Monitoring 1994 Report end total aubeidence. These tables indicate that the maximum total subsidence to date is 8.53 feet and occur ovw both the F- and B-Seams at point No. 61, which u over the eentw of the 1st Northwest Longwell Pond. The subsidence measured is well within the range of the predicted subsidence (Exhibit 60). In this area of two-seam mining, wmplete msrdmum subsidence can be calculated by simple addition of the maximum predicted subsidence for both the F and B Soma. The total predicted subsidence for the 2-eeem mining ie 10.22 feet. There were no additional visual effects of aubaldence reported during thin period of monitoring. There was, howevw, a recent follow-up invaeigation and discussion submitted to the Division regarding the cracks that wwe observed and reported in the 1994 Mid-year Report (Semi-Annual Subsidence Monitoring Report 1994), Monitoring of awood-framed structuro conswcted in 1994 over the pillar between the BS and B6 Northwest LongwaU panels (NWLW), after mining the BS NWLW panel resulted in an overall lowering of the Bite by an average of 1.52 fat and an average esstwly horizontal shift of 1.71 feet. No damage to the building has ocwtted. A photo panel wntrol point located nearby over the approximate middle of the BS panel lowered appmximately 4.17 fat. Mining edvence wan limited to the B-Seam development in the B-West Maine, Jumbo Maine, and the Sixth, end Seventh Northwest Hoadgates, i}om July 1994 to October 1994. The longwatl retreated in the B4 and BS Northwest Longwell Panob (NWLW) since July 1994. The longwall is currently (April 1995) retreat mining in the B6 NVi-LW Panel. aub1994,doc.