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Wesr Elk Mine <br />• low permeability. As MCC has included rock drains and a HDPE liner (for Phase 1 and 2) into <br />the construction of the RPE, and will build future phases in an area that has clay subsoil with low <br />permeability, it is very unlikely that there will be a negative impact on the quality and quantity of <br />groundwater in the vicinity of the IZPE. <br />Table 64 <br />Avera a Acid-Base Potential for Overburden Samples <br /> <br />Location of Samples Sulfur Form Used for <br />Calculating <br />Acid-Base Potential Weighted-Average <br />Acid-Base Potential <br />(t CaCOa eq./1000 t material) <br />F Seam Roof ritic +6.3 <br />F Seam Floor ritic -2.2 <br />F Seam Total ritic +1.9 <br />E Seam Roof total +75.7 <br />E Seam Floor total +16.5 <br />E Seam Total total +54.4 <br />B Seam Roof total +g4.3 <br />B Seam Floor total +12.3 <br />B Seam Total total +66.0 <br />g + E Total total +61.2 <br />g + F Total +19.5 <br />Total of All Strata +25.3 <br />Monitoring, Protection, and Mitigation ofPro6able HydroloQic Consequences - 2.05.6 (3)(a&b) <br />Surface Water <br />Despite the fact that MCC's findings indicate that there will not be significant hydrologic <br />consequences to downstream water users, wetlands, other aquatic resources, etc., MCC currently <br />has in place and will expand, as necessary, its comprehensive monitoring and mitigation program. <br />For example, the Colorado Water Court decree for the Dry Fork Augmentation Plan (included as <br />Exhibit 52) provides a detailed description of those stream gages that will be utilized to determine <br />whether hydrologic changes are occurring in the Dry Fork basin as a consequence of subsidence. <br />The same Decree, and proposed mitigation plan, offers protection in the event that monitoring <br />reveals hydrologic changes. For example, as a last resort, MCC will maintain materials onsite to <br />convey streamflows over cracks that might develop in stream channels. Pumps and discharge pipe <br />will be kept onsite to lift water from the mine workings to the Dry Fork if losses are observed. If <br />these measures aze not adequate, MCC will cease diverting its senior water rights on Minnesota <br />Creek neaz Paonia, thereby leaving the water in the stream to satisfy water users. MCC has <br />extensive portfolios of water rights on both the Dry Fork and North Fork. <br />MCC is prepared to implement and conduct its augmentation plan commitments on the "time-step" <br />basis specified by the Colorado State Engineers Office, whether it be daily, montlily, by season or <br />annually. MCC is prepared to utilize its North Fork rights in the same manner as described in the <br />Water Rights section of this text. <br />. MCC collects mine water inflows and operational runoff water in the mine, and pumps it duectly to <br />Lone Pine Gulch, Sylvester Gulch and/or the North Fork per NPDES dischazge requirements, to <br />2.05-193 RevrsedJune 1005 PRIO; Rev. Minch 7006; Rev. May 2006 PRIO <br />