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temperatures of the 14 SEHG fault water were a few degrees cooler. Both BEM and 14 SEHG fault waters were pumped to the NETG sump prior to being pumped into the NW Panel sealed sump or discharged to the North Fork of the Gunnison River via existing NPDES discharge points. The NETG sump is located at the southeast end of the lONE longwall panel and had an original capacity of approximately 900,000 gallons. It is believed that the capacity of the sump has been reduced due to sediment deposition. The temperantre of most of the water pumped from the NETG stamp into the NW Panels sealed sump is unknown. However, the data indicate that considerable cooling occurred in the mine prior to pumping to the NW Panels sealed sump. These data include: 1) temperature of 14 SEHG fault water dischazged from the mine portal and 2) recently measured temperature of water in the P1ETG sump, and 3) recently measured temperature of water discharging from the Lone Pine seals. 14 SEHG fault water, which was pumped from the NETG sump to the mine portal between 7anuary 25 and February 7, had cooled from about 89°F at the inflow Iocaiion to 75°F at the mine portal. Because this water was piped from the NETG sump to the mine portal, most of the cooling occurred whoa rho water was standing in the flooded Box Canyon Mains and in the NETG sump. Ia December 1997 the temperature ofNETG sump water, prior to discharge into the NW Panels sealed sump, had cooled to t54°F. The cooler temperature of NETG sump water is December 1997 relative to the mine pornl discharge temperature is early 1997 is attributed to a longer residence time in the NETG sump and as increased percentage of mine process water. A Longer residence time is the result of the lower discharge rate from the 14 SEHG fault in late 1997 relative to eazly 1997. ~. The 64.4°F temperature of a sample from the Lone Piae seal at the outlet of the NW Panels sealed stamp also suggests thaz fault water stored in the NW Panels sealed sump has cooled. However, the chemical data indicates that this water is a mixnue of thermal fault water and other cooler water arch as surfice or process weer. Dtscttssion The temperature data do not support the allegation that NW Panel sealed sump water is the major source of water issuing from the Edwards Mtne portal springs. We base this conclusion on two lines of reasoning. First, based on temperature data in the WEM, we believe that the average temperature of fault water pumped to the NW Panels sealed sump was less than 80 °F and may have been as cool as 75°F. The tempcratucc of water discharging from the Edwards Mine portal spring, 81 to 87 °F, is greater than the likely temperature of water in the NW Panels sealed sump. Second, if water discharging from the Edwards Mine portal spring were NW Panels sealed sump wazer it would have had to cross two coal barriers and then travel on the 2