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West Elk Mine to the longwall panels beneath Gribble Gulch and Lone Pine Gulch. Also, as stated in the October (~ 24, 1994 CDMG Decision Document on the Jumbo Mountain Tract (see page 31), "A direct fracture connection to the mine was not established in Lone Pine Gulch under a cover as low as 120 feet (when F-Seam mining was occurring)." Similazly, mining of the B East Mains beneath Sylvester Gulch did not produce a connection with the surface. The groundwater emanating from the B East Mains fault had, and continues to have temperatures in excess of 80°F. This combined with the lack of tritium, 14C and 180 isotopes, (Mayo 1998) indicates this water is not connected to local surface waters. Additional considerations regarding surface water effects include the following: Mining in the Apache Rocks permit revision area will not measurably impact the surface water hydrologic balance of the Dry Fork of Minnesota reek. Based strictly on surface acreage, this azea contributes only 22 percent of the Dry Fork of Minnesota Creek drainage basin flows as measured above the Lower Dry Fork gage. Because the azea is on a south facing slope, however, the actual percentage of surface runoff will be lower. MCC's 1986 Minnesota Creek Augmentation Plan, Case No. 86CW38 (approved by the Colorado Water Court), provides for total replacement of the annual streamflow generated in the Dry Fork basin. For these reasons, impacts to the Dry Fork of Minnesota Creek will be minimal due to B and/or E-Seam mining. 2. Mining in the Box Canyon permit area will not measureably impact the surface water hydrologic balance of the North Fork. As previously stated, 100 percent of the mining ~, area has a B-Seam overburden thickness of more than 500'feet, thus all but eliminating the possibility of surface water capture by the mine workings. 3. Based on the B-Seam mining plan, in the current permit, which includes the Box Canyon permit revision area, it is not anticipated that there will be duect mining impacts to Sylvester Gulch. In summary, based on the small amount of surface flow that occurs annually, the low probability of surface cracking due to subsidence, and the depth of cover and the character of the overburden materials within the permit azea, the projected mine subsidence will not significantly impact the streams. Springs/Seeps This section addresses PHCs for the springs and seeps in the current and Box Canyon and West Flatiron permit revision azeas. i i Frvgyy~~f'nrrvrranra WWII Natvra ~f CnTO` -There are 69 springs in the current permit area. More than 90 percent of these have at least 270 feet of overburden above the highest seam to be mined. Four springs in the current pemut azea exhibit significant flows: Spring G-26A (peak flow during spring runoff up to 75 gpm) in Lone Pine Gulch; G-24 (up to 120 gpm) in Sylvester Gulch, ', and G-25 (up to 90 gpm); G-31 (up to 45 gpm) in Gribble Gulch; and D-2, J-4 and J-10 (up to 30 gpm) all in the Apache Rocks permit revision area. 1.05-156 November 1004 PRI!