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Statement of BME subsidence predictions. • Results to date. • Comparison between the prediction and results to date. • Half foot subsidence difference contour map and profiles for each survey. • Printout of the elevation data. • Topographic base map. The data derived from subsidence monitoring is expected to enable BME to make accurate predictions of subsidence and strain over subsequent panels. It will be possible to make accurate predictions of the timing and magnitude of any subsidence that may affect the county road, so that BME can take appropriate actions, i.e., repairs and traffic control. Similar predictions will also be possible for panels that may produce subsidence near Red Wash and Scullion Gulch. Upon completion of production mining within room and pillar panel RP-1 and longwall panel LW-1, BME was to prepare analysis of the subsidence monitoring data collected to that date. If the results of that analysis determined that a revision of the mining plan for the remainder of the mine was appropriate, BME was to complete the appropriate revisions and submit them to the regulatory authority for review. Analysis of LW1 subsidence data showed that a revision in the mine ptan was not warranted. BME requested and DMG waived the subsidence monitoring requirements of RP-1 by analytical photogrammetry as long as significant unanticipated ground movement did not occur above RP-1. BME will continue visual • inspection above RP-1 twice a year and complete any required repairs. A report of such inspection shall be submitted annually. The annual report will include description or sketch of the visual inspection route, and description, location, and photographic documentation of any potential expressions of surface subsidence, along with a description of any repairs conducted. If significant ground movement above RP-1 is noticed and if DMG so directs, BME will complete an aerial photogrammetric survey and submit a subsidence map within six months of DMG's request. DMG and OSM have determined that the best mitigation for archaeological sites subject to potential subsidence was to limit access to the area and limit access to the location information. It was determined that subsidence itself did not produce a detrimental impact to the cultural resources. Subsidence is expected to produce no long term impacts on these sites. Subsidence predictions have been approached from a conservative standpoint and actual measured subsidence has always been less than predicted. Depth increases as the mine progresses to the north and as depth increases, subsidence is decreased. As acknowledged by DMG and OSM, subsidence of archaeological sites over LW-2 was found to not cause significant impacts. The sites in lease COC-51551 were predicted to undergo less subsidence than the sites over LW-2 and therefore are not expected to be significantly impacted. However, longwall mining under these sites did not occur since this area became inaccessible when part of the D Seam was sealed due to the fire. Permit Renewal #3 (Rev, 8/99) III-26