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Environmental Protection Plan, Schwartzwalder Mine 15 -2 The potential sources of uranium loading to Ralston Creek that have been identified by DRMS and that will be addressed through the EPP process include alluvial groundwater in contact with fill material, the waste rock piles, and the mine pool. However, the EPP process prescribed in the Colorado Hardrock Mining Rules does not take into consideration the steps for investigation and selection of a remedy that would typically apply to environmental cleanup programs. These steps typically include remedial investigation, identification of potential sources, determination of remedial objectives (or risk -based clean up levels), identification of potential mitigation alternatives, feasibility analysis and selection of alternatives, implementation of mitigation action, and monitoring the effectiveness of the mitigation. (b) Remedial Objectives Cotter, DRMS, MLRB, WQCD, and Denver Water share a common remedial objective at the Schwartzwalder Mine site, which is to effectively and permanently protect water quality in Ralston Creek. Implicit in this objective is a need to achieve this remedial outcome in the shortest time frame possible. Cotter has identified two mitigation options to protect water quality in Ralston Creek as quickly as possible: pumping and treating ground water in the alluvium and isolating the creek from interacting with groundwater in the alluvium. These short-term mitigation options are described in Section 15(c) and 15(d), below. With respect to long -term remedial objectives for the site, site characterization is ongoing and can only be fully achieved once the alluvium and fill area has been temporarily dewatered. The final determination of the most appropriate mitigation strategies for the site should be based on site characterization data and accepted principals for evaluation of remedial alternatives. The selection of long -term mitigation strategies at the site should include optimization of the following fundamental remedial criteria: 1. Quantitative Effectiveness. Consistently and permanently meet all applicable water quality standards in Ralston Creek, with particular emphasis on the uranium standard (0.03 mg/L) as this is the only parameter that exceed applicable water quality standards due to impacts from the mine site. 2. Sustainability. Maximize long -term sustainability through cost - effectiveness and minimization of long -term burdens to future generations and any indirect costs to society. 3. Minimization of Health Risks. Minimize overall potential risks to public health, including those related to water quality in the creek and those directly or indirectly associated with the remedial measure itself. 4. Minimization of Environmental Impacts. Minimize impacts to the environment, including preservation and restoration of local ecosystems and wildlife as appropriate with respect to future land uses deemed most appropriate and beneficial to society. The long -term mitigation strategies that have been identified by Cotter for achieving the stated remedial objective (protection of water quality in Ralston Creek) include source removal (Section 15(e)), plugging and abandonment (Section 15(f)), and mine pool stabilization and detoxification (Section 15(g)). Monitoring the short-term and long -term effectiveness of these remedial actions is critical to optimizing the mitigation program and meeting the stated remedial objectives. Cotter routinely monitors groundwater and surface water in accordance with the approved monitoring plan described in Section 12 of the EPP. Surface water quality is monitored monthly at twelve locations on Ralston Creek, including one upgradient station, six stations in the central mine area, one station at the outfall from the water treatment plant, one station at the property boundary (SW -BPL), and three stations downstream of the property boundary (SW- 4109C.110510 Whetstone Associates •