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Technical Revision 25, Rev. I Schwartzwalder Mine <br /> 60-mil, high density polyethylene ("HDPE") liner to construct the secondary containment, which is the <br /> same material currently in use at the mine. <br /> 3.2 FACILITIES EVALUATION <br /> This section provides an evaluation of the expected effectiveness <br /> p p of new structures discussed in Section <br /> 3.1. Information presented in this section is required by Hard Rock, Metal, and Designated Mining <br /> Operations Rule 6.4.21(7). In many cases, the information required in this section is found in <br /> Schwartzwalder Mine, Environmental Protection Plan, Revision 1.0 (Revised EPP) (Whetstone 2016). <br /> Therefore, Cotter will not repeat that information here, but will cite the appropriate sections of the latest <br /> EPP. <br /> 3.2.1 Site-Specific Conditions <br /> Sections 1.0 and 2.0 of the Revised EPP present information regarding site-specific conditions <br /> (Whetstone, 2016). <br /> 3.2.2 Designated Chemicals <br /> - The following information is from Section 6.0 of the Revised EPP (Whetstone, 2016). <br /> Rule 6.4.20(6) requires that this section of the EPP fully describe the procedures for the disposal, <br /> decommissioning, detoxification or stabilization for all designated chemicals and toxic or acid-forming <br /> materials. The EPP must describe measures to be taken to prevent any unauthorized release of pollutants <br /> to the environment and must include adequate reclamation and closure practices for such designated <br /> chemicals, toxic or acid-forming materials and describe how unauthorized discharge of acid mine <br /> drainage will be prevented. <br /> No designated chemicals are currently in use or being stored at the Schwartzwalder Mine site. No acid- <br /> forming materials exist onsite. Native rock at the Schwartzwalder Mine is not acid-generating. Instead, it <br /> is classified as having a low potential to generate acidic drainage, and no acidic drainage has occurred <br /> from the mine or waste rock facilities to date. Geochemical characterization of the waste rock piles is <br /> described in Section 14 of the Revised EPP. The water quality of the flooded mine workings is described <br /> in Section 9(b)(iv) of the Revised EPP. The pH of groundwater in the flooded mine is near neutral, and <br /> has been stable (no obvious increasing or decreasing trend) since monitoring of mine water began in <br /> 2000. The mine pool has shown no potential to generate acid. <br /> The flooded mine workings and the alluvium and fill have been identified as toxic-forming materials on <br /> the basis of(1) uranium and radium-226 in groundwater in the underground mine pool and (2)uranium in <br /> groundwater in the alluvium and fill. The hydrogeologic conceptual model is described in Section 8(e) of <br /> the Revised EPP. Water quality in the mine pool is summarized in Table 9-8 and discussed in Section <br /> 9(b)(iv) of the Revised EPP. Water quality in the alluvium and fill is summarized in Table 9-3 and <br /> discussed in Section 9(b)(ii) of the Revised EPP. Potential mitigation options for groundwater are <br /> discussed in Section 15 of the Revised EPP along with a proposed schedule for feasibility investigations, <br /> engineering design, and implementation. <br /> Mine Permit M-1977-300 <br /> Cotter Corporation(N.S.L.) 14 June 2017 <br />