2009-05-22_GENERAL DOCUMENTS - C1981044

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elevation measured in the AVF-5 Well in June 2002 and should not be indicative of mining impact. Compliance with the Basic Standards for Ground Water (Regulation 41 of the Colorado Water Quality Control Commission) Section 4.05.13(1) of the Regulations requires the establishment of one or more ground water points of compliance (wells) for an operation which has the potential to negatively impact the quality of ground water. The mine monitors the Middle Sandstone in well TR-7a and the Williams Fork alluvium in well AVF-5. The TR- 7a well is within the expected bedrock flowpath of mine leachate, should the mine discharge leachate to bedrock units. The AVF-5 well is within the expected alluvial flowpath of leachate, should the mine discharge leachate to Williams Fork River alluvium. AVF-5 is also within the expected flow path of pumped mine water, should mine water adversely impact the alluvial water. Both wells meet the qualifications of a compliance point, as those qualifications are listed in Section 4.05.13(1)(b). Monitoring data from both wells indicate the mine has not caused an exceedance of the Basic Standards for Ground Water. Observed Surface Water Impacts Discharges from the 5 and 6 Mines have not caused measurable depletion of stream flows in the mine vicinity. If all of the mine inflows during active mining (approxi- mately 2 cfs) came from the Williams Fork and Yampa Rivers, it would be too small of a depletion to detect in those rivers' 7-day/10-year low flows. Monitoring data in the annual hydrology reports from 1981 through 2008 indicate the Eagle Mines have not significantly impacted the water quality of the Williams Fork River. G. No surface water is proposed to be discharged into, or directed into, underground mine workings. H. BTU EC does not plan to convert any monitoring wells to water supply wells. 1. Stream Buffer Zones - Rule 4.05.18 The Eagle Mine Complex includes several structures which are located within 100 feet of the perennial Williams Fork River. These structures are a coal storage silo, a 48-inch cross country conveyor, waste water ponds, No. 5 Mine dewatering wells and associated substation and access road, haul road bridge, well 259 and pond HR-Pl, and rail road at tail track end. The conveyor is an enclosed structure as it crosses the river and the highway, therefore minimizing disturbance to the stream. The coal storage silo is a concrete structure utilized to load railroad cars. These variances from the 100-foot buffer zone for perennial streams have been granted by the Division upon finding: 1) that the original stream channel will be restored; 2) during and after mining, the water quantity and quality from the stream section from within 100 feet of the surface coal mining operation shall not be adversely affected; and 3) that the operation's reclamation plan provides for the reestablishment of the appropriate riparian vegetation. Locations of these Eagle Mine Complex 26 Permit Renewal 05 C-1981-044 May 22, 2009