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<br />temperatures of the 14 SEHG fault water were a few degrees cooler. Both BEM and 14 <br />SEHG fault waters were pumped to the NETG sump prior to being pumped into the NW <br />Panel sealed sump or discharged to the North Fork of the Gunnison River via existing <br />NPDES dischazge points. The NETG sump is located at the southeast end of the LONE <br />longwall panel and had an original capacity of approximately 900,000 gallons. It is <br />believed that the capacity of the sump has been reduced due to sediment deposition. <br />The temperature of most of the water pumped from the NETG sump into the NW Panels <br />sealed sump is unknown. However, the data indicate that considerable cooling occurred <br />in the mine prior to pumping to the NW Panels sealed sump. These data include: <br />I) temperature of 14 SEHG fault water discharged from the mine portal, and <br />2) recently measured temperature of water in the NETG sump, and <br />3) recently measured temperature of water discharging from the Lone Pine seals. <br />14 SEHG fault water, which was pumped from the NETG sump to the mine portal <br />between Januazy 25 and February 7, had cooled from about 89°F at the inflow location to <br />75°F at the mine portal. Because this water was piped from the NETG sump to the mine <br />portal, most of the cooling occurred when the water was standing in the flooded Box <br />Canyon Mains and in the NETG sump. <br />In December 1997 the temperature of NETG sump water, prior to dischazge into the NW <br />Panels sealed sump, had cooled to 64°F. The cooler temperature of NETG sump water in <br />December 1997 relative to the mine portal discharge temperature in early 1997 is <br />attributed to a longer residence time in the NETG sump and an increased percentage of <br />mine process water. A longer residence time is the result of the lower discharge rate <br />from the 14 SEHG fault in late 1997 relative to early 1997. <br />The 64.4°F temperature of a sample from the Lone Pine seal at the outlet of the NW <br />Panels sealed sump also suggests that fault water stored in the NW Panels sealed sump <br />has cooled. However, the chemical data indicates that this water is a mixture of thermal <br />fault water and other cooler water such as surface or process water. <br />Discussion <br />The temperature data do not support the allegation that NW Panel sealed sump water is <br />the major source of water issuing from the Edwards Mine portal springs. We base this <br />conclusion on two lines of reasoning. <br />First, based on temperature data in the WEM, we believe that the average temperature of <br />fault water pumped to the NW Panels sealed sump was less than 80 °F and may have <br />been as cool as 75°F. The temperature of water discharging from the Edwards Mine <br />portal spring, 81 to 87 °F, is greater than the likely temperature of water in the NW <br />Panels sealed sump. <br />Second, if water discharging from the Edwards Mine portal spring were NW Panels <br />sealed sump water it would have had to cross two coal barriers and then travel on the <br />2 <br />