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b) In accordance with Rule 6.4.20(10)(iii), capture and/or retain surface water <br />run-off from areas affected by the Designated Mining Operation prior to its <br />release from the mine- site into the natural water drainage system. <br />c) Remove the alluvium and replace with inert fill. <br />d) Pump and treat the pore water in the alluvium. <br />e) Isolate the creek from the alluvium. <br />7) Because the alluvium is containing toxic-forming materials, DRMS contends that the alluvium <br />should also be designated as an Environmental Protection Facility and therefore subject to the <br />provisions of Rule 6.4.20(7)(e). Operator must describe any release response procedures, <br />redundancies, and "backup" measures necessary, appropriate, and economically reasonable, to <br />control, prevent and mitigate releases of the toxic-forming materials from the containment facility <br />(i.e., the alluvium) outside the permit area. <br />8) Operator must continue to monitor the water quality of all existing monitoring wells at the same <br />locations, frequency, and with the same analytes, as has been done historically. Any modification <br />to the ground water monitoring plan must be approved in advance by DRMS. <br />9) Operator must continue to monitor surface water quality at the same locations, frequency, and <br />with the same analytes, as has been done historically. Any modification to the surface water <br />monitoring plan must be approved in advance by DRMS. <br />10) Pg 9-3: The statement is presented that the alluvial ground water is not subject to drinking water <br />standards because the water is not a drinking water source. DRMS contends that the alluvial <br />ground water is in direct communication with Ralston Creek which terminates in Ralston <br />Reservoir, a drinking water storage facility. Therefore, the alluvial ground water is ultimately a <br />drinking water source. Additionally, the CDPHE discharge permit criterion was a risk-based <br />value that targeted the ultimate concentration in Ralston Reservoir in the context of usage as <br />drinking water. <br />11) Pg. 8-37: Was the methodology for collecting the underground Tritium samples the same as that <br />described in Section 9.b.(iv).3 on page 9-48 for the other underground water samples? If not, <br />please provide the procedure describing how the Tritium samples were collected. <br />12) Table 9-7: Was the Fe 3+ analyzed from a filtered or an unfiltered sample? <br />13) Table 8-5 and Figure 8-11 indicate that MW-11 is a bedrock monitoring well, but MW-11 data <br />are included in Table 9-2 for alluvial monitoring wells. Please clarify. <br />14) The most recent data in the EPP only includes through October 2008. Please provide current data. <br />15) Please provide a copy of the Yang and Edwards (1984) publication that reported that the upstream <br />U concentration in Ralston Creek was 4.0 mg/L.