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Sandra Brown <br />March 7, 2012 Page 6 <br />approximately perpendicular to contour, and appear to vent the C Seam. These venting features <br />appear to be located near the described location of the Bear Mine No. 3 entry. This observation <br />suggests that a relationship between the entry and the fire exists. BCC has stated that the venting <br />was an indicator of fire occurring in the underlying B Seam, and that combustion gasses migrate <br />to the C Seam and eventually to the former entry location via a ramp that Bear had developed <br />between the seams. This may be possible. It is equally possible that the venting is indicative of <br />pre- combustion heating in the C Seam. Although some logical assumptions and theories have <br />been advanced, the fact is that neither Bear Coal nor the Division are able to make a specific <br />demonstration as to the location of the combustion in the sub - surface. The complex <br />interrelationship of the Bear and Edwards operations only serves to make a specific delineation <br />more difficult without some manner of subsurface investigation, or perhaps a geochemical <br />evaluation of the combustion gasses produced by the various coal seams. <br />Given the low surface heat values, and the relatively limited surface area over which mine fire <br />indicators are observable, significant heating of entrained subsurface water as a result of a low <br />intensity mine fire does not seem to be very likely. The underlying fire does not seem to be large <br />or intensive enough to provide sufficient heat to significantly raise the temperature of nearby <br />groundwater. It is possible that heating of groundwater results from subsurface geothermal <br />activity potentially related to the Tertiary intrusive rocks of the nearby West Elk Mountains. <br />Water Quality Analysis of Seep <br />The Division and the Bear Coal Company have studied the water quality of the seep extensively. <br />The seep has been inspected monthly by the Division since it's occurrence in 1997 and still flows <br />at a relatively constant rate of 5gpm (approximately half of its initial flow in 1997) has a reddish - <br />brown color and elevated temperature. In September 2004 the Division did a full -suite analysis <br />of the spring and the results showed the water as being benign. One item of interest was the <br />possible high- molecular weight organic acids. It was postulated that this might be humic acids. <br />In January 2005 the Division performed further testing in an attempt to further characterize the <br />water. This included sampling the North Fork of the Gunnison River both upstream and <br />downstream to determine what, if any, impacts the discharge was having on the receiving stream. <br />These data are tabulated and provided in Attachment 2. The samples taken in January 2005 have <br />the same concentrations of metals as those taken in September 2004 and both data sets show no <br />really high values for any of the analytes tested. The only metal that is included in the CDPS <br />permit for the Bear No. 3 Mine is iron. The reported level of iron in the "Edwards Portal spring" <br />was 2,500 ug/l which is well below the maximum allowable level of 6,000 ug/1 in their CDPS <br />permit. <br />The main item of interest with regards to the Edwards Portal spring is the reddish -brown color of <br />the water. The color is not coming from the iron or any other metal (iron at the low <br />concentrations observed will not impart that color to the water). A full suite of organic analyses <br />was performed on the water in September 2004 and no organics (volatile or semivolatile) were <br />detected. There was the possibility of high - molecular weight organic acids in the water. It was <br />postulated that these acids could be humic acids and there was some anecdotal evidence to <br />support this theory. The Division sent additional samples to the Colorado State University <br />