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2.05.6(3) Protection of the Hydrologic Balance <br />• The mining operation could impact the flow of water through the ephemeral surface <br />drainages located above the area to be mined. The ephemeral drainages above the Bear <br />No. 3 Mine are very steep. The effect of subsidence would not reverse the grade of the <br />drainages. The flow through the drainages could temporarily be effected by a subsidence <br />crack. However, a subsidence crack would be expected to heal fairly quickly so the surface <br />drainage pattern would be naturally restored. <br />(a)(iv) The portals of the Edwards Mine which are now used for the Bear No. 3 Mine were in <br />place prior to the adoption of the regulations concerning the location of such openings. <br />Furthermore, gravity discharge of water from the portals is not expected. <br />(b)(i) As explained in (a)(i) above, a sedimentation pond has been installed to control the <br />surface water drainage through the surface facilities area. Other surface drainage from the <br />permit area and adjacent areas is allowed to flow though ephemeral channels unimpeded <br />by the mining operation. The Bear No. 3 Mine is sealed. Drain pipes (4-inch diameter) were <br />installed through each seal. <br />(b)(ii) Surtace run-off from the facilities area does not require treatment, other than the <br />detention time provided by the sedimentation pond. A spring emerged from a slide area in <br />. 1997. This water is currented passed through a passive treatment pond prior to its <br />discharge to the North Fork of the Gunnison River. <br />(b)(iii) The Bear No. 3 Mine surface facilities, including a coal stockpile, are constructed on <br />an alluvial deposit located adjacent to the North Fork of the Gunnison River. Alluvial wells <br />AA1 and AA3 are located downstream and upstream of the facilities area respectively. The <br />results of water analyses taken from both wells through 1985 did not indicate any <br />degradation of the water in the alluvial material. In 1986, no samples were sent to the <br />laboratory for analysis but the field tests for the third quarter did indicate an elevated <br />conductivity in the downstream well, AAi, of 2250 uhmos/cm. <br />Beginning in 1987, the field conductivity tests and the laboratory analyses of water samples <br />from AA1 did begin showing some degradation of the quality of water in the alluvial material. <br />Total dissolved solids, measured in ppm, increased from the 400 to 500 range, prior to <br />1986, to a 1000 to 2800 range from 1987 through 1996. The water samples obtained from <br />well AA1, from 1987 through 1996, show elevated levels of magnesium, sodium and sulfate <br />compared to water samples analyzed from AAi prior to 1986 and compared to water <br />samples analyzed from AA3 which is upstream of the facilities area. The water samples <br />from well AAi do not indicate degradation with respect to total recoverable metals. <br />~J <br />2.05-55a <br />Rev. 1/03 <br />/'1 R-a5 <br />(,2N -0 4~ <br />/)/?RoV~ l~/IY~o3 <br />