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1 <br />t MEMORANDUM <br />' TO: Kathy Welt <br />Mountain Coal Company <br /> <br />' FROM: Wright Water Engineers, Inc. <br />Jonathan Kelly and Jon Jones <br /> <br />' DATE: July 20, 1998 <br /> RE: Minutes from June 30 Meeting at CDMG Regarding Hydrologic and <br /> Hydraulic Issues Associated with MCC's Water Management Activities <br />' And Bear Mine Inflows <br />' Jon Jones and Jonathan Kelly joined Kathy Welt and Phil Schmidt on June 30, 1998 al the <br /> offices of the Colorado Division of Minerals and Geology (CDMG) for a meeting with Dave <br /> Berry, Mike Boulay, Susan McCannon, and Larry Routten. The purpose of the meeting was <br />' to present new information and refined analyses regazding hydrologic and hydraulic issues <br /> associated with Mountain Coal Company's (MCC) water management activities and Bear <br /> Mine inflows. <br /> Phil began the meeting by noting that this meeting represented the third in a series of <br /> meetings geared toward presenting new information relevant to the violation issued by <br />' CDMG concerning the water discharge and landslide near the Bear No. 3 Mine. The <br /> previous meetings addressed the issues of water quality and geologic/geotechnical issues <br /> related to the Bear landslide. This final meeting was to complete the evaluation by <br /> addressing the hydrologic and hydraulic issues. <br /> Next, Kathy provided a detailed review of the progression of mining at and associated water <br />' management activities at the West Elk Mine. Key points made by Kathy during her <br /> presentation included: <br />' • Began mining in longwall panel 1NW in 1992. Operations water used for cooling and <br /> dust suppression on the longwall face was allowed to flow down dip to an operational <br /> sump at the northeast comer of 1NW. The water was then pumped to the slope sump and <br />' out of the mine to the sedimentation ponds. This practice continued during mining of <br /> longwall panels 2NW and 3NW. <br /> • The water management changed slightly while mining 4NW and SNW. Since all water <br /> would not flow via gravity along the dip to the northeast comer of 1NW, water was <br /> pumped with air-powered pumps from the northeast comers of 4NW and SNW to the <br />' north end of 3NW where it would flow to the northeast comer of INW and then was <br /> pumped out of the mine, as above. In addition, process water from the continuous miners <br /> in the Jumbo North Mains and small inflows below Gribble Gulch were pumped into the <br />' southwest corner of 3NW at crosscut 29 while longwall mining 4NW and SNW. Water <br /> from this location flowed via gravity through the caved panels along the dip to the <br />vi <br />W <br />W <br />u <br />Z <br />W <br />OC <br />W <br />Q <br />3 <br />2 <br />oe <br />3 <br />