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to reduce measured methane, it would seem logical that both the gas wells and the coal <br />workings were a source of the methane in the soil profile. However, additional data did <br />not support that conclusion, as documented in the Division report titled "Findings of the <br />Division of Minerals and Geology, Methane Assessment, Golden Eagle Mine (with <br />addendum July 2007)" also incorporated by reference. These data indicated that no <br />clear trend could be determined related to the timing of the sealing of the gas wells and <br />the flooding of the mine workings as previously concluded. The Division's conclusion <br />based on analysis of additional data collected since 2003 is that "it seems unlikely that <br />any clear conclusions can be reached regarding the source and cause of methane in <br />the soil profile east of the Golden Eagle mine. Methane remains in the soil profile, it <br />does not appear to be spreading, and poses no hazard at this time other than dead to <br />limited areas of vegetation." <br />Methane is known to be present in the overburden between the surface and the <br />Maxwell coal seam mined at the Golden Eagle Mine. Factors such as mining, gas <br />drilling and development, along with the sub-surface dewatering associated with both of <br />these activities, could be the catalyst for liberation of methane to the surface given the <br />local geologic environment. However, without additional research, including monitoring, <br />data collection, and analysis, defining the source and cause of these methane seeps is <br />not possible at this time. While the Division acknowledges the issue identified by the <br />objector Mr. Toupal, it is not possible to positively identify the mine as the source and <br />cause of the methane in the soil profile. <br />Minimization of Hydrologic Impacts <br />Surface and ground water resources in the permit and adjacent area were thoroughly <br />described through baseline studies conducted as a result of a stipulation to the original <br />mine permit approval. Mining activities were planned and conducted to minimize the <br />impact to the hydrologic balance within the permit area and prevent impacts outside the <br />permit area. <br />Surface and ground water resources were monitored during active mining and <br />throughout the ten year revegetation liability period. The operator followed the mindful <br />approach of requesting and receiving approval for reductions in hydrologic monitoring <br />over the liability period. <br />Reclamation of the area subject to this bond release occurred in 1996 and early 1997. <br />In January 1997, Technical Revision No. 44 was approved which reduced the <br />frequency of monitoring commensurate with the probable hydrologic consequences of a <br />reclaimed mine. Water quality sampling of deep wells was also eliminated since a <br />gradient reversal toward the mine workings would preclude any potential impact to <br />bedrock water quality. <br />Although subsidence has the potential to impact surface and ground water in and <br />around the area undermined and subsided, hydrologic monitoring and subsidence <br />monitoring did not identify impacts during or after the cessation of mining. Technical <br />Revision No. 46 was approved in October 1997 and eliminated subsidence monitoring.