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EPP Adequacy Review No. 2 6 19 March 2010 <br />Schwartzwalder Mine File No. M-1977-300 <br />premise that any passive treatment technology could be zero-maintenance. Please provide a plan <br />for long-term maintenance and bonding of the facility as needed. <br />22) On page 15-6 Operator proposes installation of a permeable reactive barrier (PRB). Please <br />describe in detail the composition and construction of the PRB, the proposed loading rates, the <br />expected geochemical attenuation processes, and the expected water quality that will ultimately <br />be discharged from the PRB at the down gradient terminus. Bonding for installation will also be <br />required. <br />23) On page 15-6, Operator presents a chemical reaction for immobilization of uranium in a PRB <br />composed of ZVI. One of the products of the reaction is Fee+, resulting from the oxidation of <br />Fe°. What is the fate of the ferrous iron; is it mobilized to the aqueous phase and transported <br />downgradient, or is it left behind on the PRB? Provide a prediction of the concentration of any <br />mobilized iron in solution downgradient of the PRB. <br />24) The EPP still contains no provision for management of the mine pool. Under Hard Rock Rule <br />6.4.20(6)(a), the Operator must specifically describe measures to be taken to prevent any <br />unauthorized release of pollutants to the environment, including adequate reclamation and <br />closure practices for toxic or acid-forming materials. The mine pool has been designated as an <br />Environmental Protection Facility for containment of toxic-.forming materials under the <br />provisions of Hard Rock Rule 1.1(15). The Division is very concerned about the possibility of <br />mine pool water migrating downgradient along ground water conduits and discharging to Ralston <br />Creek. The Division rejects the Operator's assertion that, since no chemical anomalies are <br />measurable in the creek at present there is no communication with the mine pool. The cone of <br />depression that has been in existence around the underground mine workings needs sufficient <br />time to recover before a hydraulic communication can be established. Operator must include <br />long term plans in the EPP to respond to the possibility of mine pool contaminant migration. <br />This requirement is in addition to the short term directive indicated at item number 2 under the <br />section labeled "Corrective Action - Technical Revision" <br />25) On page 15-10 in the discussion of source removal, Operator states that the alluvium disposal <br />plan that was approved by the CDPHE Radiation Management Unit includes a provision to <br />dispose of contaminated alluvium in the underground workings of the Schwartzwalder Mine. <br />This proposed activity represents a change to the approved Reclamation Plan. Therefore, <br />operator cannot proceed with this activity until it has been approved by the DRMS. Detailed <br />plans must be provided to DRMS with the amendment. <br />Underground disposal of any material that may contain radionuclides or other potentially acid- or <br />toxic-forming material must be preceded by geochemical testing to evaluate the potential <br />leaching behavior of the material. The locations of the samples collected for these tests must be <br />documented as to location (by GPS coordinate), physical description of the material, quantity of <br />material, plus photographs of the material sampled. The testing methodology must be approved <br />in advance by DRMS, and should consist of a standardized accelerated weathering test such as <br />EPA method 1312 or equivalent methodology similar to that employed for TR-10. <br />26) Ground water is likely to be encountered during the alluvial extraction activities, and the water <br />will likely contain radionuclides, molybdenum and other constituents. Describe the management