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Sandra Brown <br />March 7, 2012 Page 2 <br />Underground mining in the mine area began in 1934 with an underground mine operated by the <br />Clark Coal Company. The operation changed ownership several times and is referred to as the <br />Clark/Edwards Mine, for this document I will refer to it as the Edwards Mine. The Edwards <br />Mine located in the immediate vicinity of the Bear Mine No. 3 Mine began mining in the B -seam <br />sometime in the early 1950's. Underground combustion problems began in 1954 and there is <br />documentation of coal mine combustion events in 1954 and 1958. Due to the combustion <br />problems, the operator was forced to move mining operations to the C -Seam. Portals to the C- <br />seam were constructed at the outcrop of the C -Seam, which is higher up the hill slope from the <br />B -seam outcrop. The Edwards Mine closed in 1964. <br />Bear Coal Company (BCC) states in the permit document that no water was present in the <br />abandoned workings of the old Edwards Mine at the time Bear Mine was established in <br />approximately late 1982. However, later in 2000 Bear Coal presented evidence to the Division <br />that subsurface water was accumulating in the hillside by 1989 as evidenced from conductivity <br />measurements taken in alluvial monitoring wells. BCC used the C -seam portals for access to <br />their Bear Mine No. 3 mining operations after they had cleaned up the old Edwards Mine. Once <br />all the reserves from the C seam were mined, a shaft and slopes were developed into the <br />underlying B seam. The shaft and slopes were installed approximately 2500 feet inby the portal <br />areas, with a 300 foot unmined coal barrier left in place between the Bear Mine and Edwards <br />Mine B -seam workings. Mining continued in the B seam with no problems of a mine fire or <br />elevated carbon monoxide readings. With most of the B -seam coal reserves already mined, BCC <br />decided to close the Bear No. 3 Mine when a large cave -in made further mining uneconomical. <br />Permanent seals were installed at various points in the Bear No. 3 Mine B -seam mine workings. <br />Upon completion of mining at the Bear No. 3 Mine, the C -seam portals were sealed in January <br />1997 in accordance with MSHA and the Division's requirements. Pipes were installed through <br />each of the portal seals so that water would not build up behind the seals. The pipes lead to <br />French drains that were installed on the hill slope. The locations of the three portal seal pipes are <br />documented in the BCC permit document. Although they are difficult to find in the field, the <br />Division has never seen any water in the general area of these French drains. <br />Up gradient from the Bear No. 3 Mine is the West Elk Mine at the time operated by Mountain <br />Coal Company (MCC). West Elk is a large underground mining operation that had mined out a <br />significant section of B -seam coal immediately adjacent to and up dip from the Bear No. 3 Mine. <br />Available maps indicate that the B -seam coal barrier between the West Elk and Bear Mines may <br />be as narrow as 200 feet in certain areas of the mine workings. <br />Prior to sealing the C -seam portals the Bear Mine reportedly experienced mine inflows in the <br />underlying B -seam workings in 1995 and 1996. During spring and early summer of 1996, the <br />Division learned that a large quantity of fault - related mine discharge water was being pumped <br />from an active area of the West Elk Mine to the west side of the mine (NW Panels sealed sump). <br />This storage sump was in the B -seam at a location up gradient of the Bear No. 3 Mine. The <br />inflow observed at the Bear No. 3 Mine, 3` west section, during 1995 and 1996 appeared to <br />correlate well with the use and sealing of underground sumps within the NW Panels at the West <br />Elk Mine. It is our understanding that about 385 acre -feet of fault discharge water was stored in <br />the NW Sump in 1995 through 1997. The Division worked with MCC to get a mine water <br />