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Minnesota Creek Protection Plan -Addenda The Minnesota Creek Protection Plan occurs in two specific Exhibits within the permit application package: Exhibits 52 and 58. MCC recognizes that technological changes over the past 14 years, i.e. mining techniques, at the West Elk Mine have caused some portions of the Minnesota Creek Protection Plan to become invalid while others remain in effect. For example, mining in the South of Divide permit azea will be performed using a state of the art technique, longwall mining, which allows for controlled subsidence, that is substantially different from room and pillar methods described in the original protection plan. In the 25 yeazs since the protection plan was created, the subsidence phenomenon at West Elk Mine are now more clearly understood and key elements of the protection plan have been incorporated in the permit application package. Three of these elements include the subsidence, hydrologic, and mitigation plans. Detailed subsidence monitoring was conducted over the initial longwall panels in the B Seam. In addition, Rich Dunned has performed annual field studies over the past decade. Mining in the SOD permit area will occur in the E Senn, the overburden of which is a subset to that of the B Seam. Additional subsidence monitoring is proposed in the SOD permit area to confmn the subsidence parameters in Exhibit 60B. The hydrologic monitoring plan (Exhibit 71) in the SOD permit application goes beyond the plan contemplated in the Protection Plan. In addition to the Upper and Lower Dry Fork stations, gages are proposed for the Deep Creek Ditch prior to dumping into Dry Fork and for Dry Fork at the inlet to Minnesota Reservov. The mitigation plan in the permit application incorporates the two main components included in the Protection Plan. Disruption of flow as a result of mining activities will be mitigated using culverts to convey flows across the impacted channel section in the short term, until more long-term measures, such as sealing the channel with bentonite, can be implemented. In the unlikely scenario that surface flows enter the mine workings, water maybe pumped to the surface and discharged above Minnesota Reservoir in accordance with the Mountain Coal Company, LLC (MCC) discharge pemrit. Water quality, primarily total dissolved solids, will be monitored to ensure suitability for the downstream irrigation use. In summary, these mitigation measures in concert with the hydrology monitoring and subsidence monitoring, and protection measures selected in the permit application protection plan continue to support the adjudicated augmentation plan for Dry Fork and the Protection Plan.