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AM-02 EPP Adequacy Review 4 14 December 2010 <br />Schwartzwalder Mine File No. M-1977-300 <br />4) Rule 6.4.21(7) - Facilities Evaluation <br />A) Provide the basics of a contingency plan for mitigation of uranium and other constituents being <br />released from the AFA to Ralston Creek in the event the activities being performed under TR-14 do not <br />result in acceptable water quality in Ralston Creek. The specifics of the plan would be provided in a <br />future TR to be submitted as appropriate. <br />B) In accordance with Rule 6.4.21(7)(e), describe any release response procedures, redundancies, and <br />backup measures necessary, appropriate, and economically reasonable, to control, prevent and mitigate <br />releases of toxic materials from the containment facility (defined herein as the underground workings). <br />Response to this adequacy issue parallels and will partially satisfy the adequacy issue 1.B.3. <br />5) Rule 6.4.21(8) - Ground Water Information <br />A) Table 8-11 reports packer test results. Does the borehole number indicate the mine level at which <br />the test was conducted, i.e., borehole 19D-53 indicates a borehole drilled from the 19 level? If that is <br />correct, then it appears that all packer tests were conducted at the 15 level or deeper. Statements are <br />made in various sections of the EPP that the bulk hydraulic conductivity of the bedrock is on the order <br />of 1.0E-07 to 2.8E-07 cm/sec. Is this estimate of the bulk hydraulic conductivity based on the packer <br />test results from mine level 15 and deeper? If so, it excludes the hydraulic properties of the upper two- <br />thirds of the mine workings. Independent assessments suggest that fractures in deeper workings of the <br />mine are less transmissive to ground water flow relative to fractures in shallower workings, and <br />therefore the packer tests at depth may significantly underestimate overall mine hydraulic conductivity. <br />Please provide an assessment of the validity of bulk hydraulic conductivity estimates that are biased <br />toward only the lower one-third of the mine workings. <br />B) Section 8(b)(iii)4, page 8-34. The EPP states that mine pool levels are measured twice daily. As <br />part of environmental protection measures, Cotter must provide the Division daily mine pool elevations <br />on a monthly basis. The data may be provided electronically. <br />6) Rule 6.4.21(9) - Ground Water Quality Data <br />A) Under Rule 6.4.21(9)(b), the operator is required to collect ground water quality data adequate to <br />characterize baseline conditions and sufficient to serve as a basis for the evaluation of reclamation <br />performance standards. Monitoring wells MW-10 and MW-11 are the only monitoring wells available <br />with which to determine baseline bedrock ground water quality and thus serve as a basis for the <br />evaluation of reclamation performance standards for the mine pool. However, both wells appear to be <br />compromised. Therefore, in order to come into compliance with Rule 6.4.21(9)(b), the operator must <br />replace these two wells in locations that will provide the needed data. <br />B) Section 9(b)(iv)2. Evaluation of Chemical Trends in Mine Water as a Function of Time (page 9- <br />43). Uranium is but one of several constituents that are of concern in the mine pool. For example, <br />radium-226 concentrations in the mine pool are significantly elevated above standard and have shown a <br />disturbing long-term increasing trend going back to December 1998. Please provide your assessment as <br />to why the radium-226 concentration has shown such a significant increase in the mine pool.