2009-08-06_INSPECTION - C1996083

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III. COMMENTS -COMPLIANCE Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. Background The purpose of this inspection was to examine the success of Bowie Resources LLC in preventing material damage and diminution of reasonably foreseeable use of structures and renewable resource lands due to subsidence at the Bowie No. 2 Mine. The inspection was oversighted by the Office of Surface Mining (OSM) as part of their Special Focus Topic review. Present were Bill Bear and consultant Jim Stover, representing Bowie Resources LLC (BRL), Howard Strand and Elizabeth Schaeffer, representing the OSM oversight team and Joe Dudash, representing the Colorado Division of Reclamation, Mining and Safety (Division). On July 6, 2009, the Division met with the OSM oversight team at the Division's offices in order to review permit application information that was pertinent to subsidence. Examined were the Bowie No. 2 mine plan, the inventory of structures and renewable resource lands, the approved subsidence monitoring program and the last two subsidence monitoring reports. The review concentrated on subsidence effects from mining that had occurred in the last 24 months. In the office review, it was determined that the mining that had occurred in the last 24 months involved the B-seam longwall panels B-6 and B-7, which are located beneath Freeman Gulch. The B-seam coal mining in this area, however, had occurred underneath the previously mined D-seam coal, so subsidence due to the coal extraction of two overlying coal seams, or double seam mining, had occurred. This permit application information was also put onto a compact disc and sent to OSM for their further review. The field inspection concentrated on verification of structures, renewable resource lands and subsidence monuments over longwall panels B-6 and B-7 in Freeman Gulch. Since subsidence could cause seismic events, BRL had prepared geotechnical studies and set up a geotechnical and seismic monitoring program to monitor the Bruce Park Dam and the adjacent landslide. Although the seismic monitoring program was not included in the Special Topic Oversight, the Bruce Park Dam area was visited during the field inspection. Subsidence Special Focus Topic Inspection Using a map provided by BRL's consultant, Jim Stover, the subsidence inspection began in Freeman Gulch with subsidence monuments 8-A, 8-13, 8-C and 8-D. These monuments are located over a section of the B-6 longwall panel which had been mined in about December of 2007. These monuments are also positioned over a section of D-seam longwall panel D-3, which had been mined back in April of 2001. The total subsidence at each of the four monuments averaged about 10 feet in drop. This fairly large magnitude in subsidence was the result of double seam mining and had been predicted in BRL's subsidence analysis. Just to the south of these four subsidence monuments lies stock pond P-2. The stock pond was dry. There were no visual observations of subsidence in the area of these four subsidence monuments and stock pond P-2. The vegetation was very dense and obscured any evidence of cracks in rock strata. There was no evidence of any cracking in the P-2 stock pond embankment or pond bottom. There also was no evidence of subsidence cracks in the dirt road. Any such cracking would have healed naturally in the approximately 18 months since mining had ceased in this location.