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Surface Water Ouality Data <br />The water quality data presented in the EPP for Ralston Creek demonstrates an impairment of the water <br />supply use of Ralston Creek due to uranium concentrations exceeding the water quality standard'. The <br />EPP does clearly show that the increased uranium concentrations in Ralston Creek occur as the creek <br />passes through the Schwartzwalder Mine. Therefore, the EPP should state that an impairment of the <br />water supply use of Ralston Creek (WQCC Regulation No. 38) is occurring due to the creek passing <br />through the mine property. <br />Groundwater Oualitv Standards <br />On page 9-3, the EPP states: "The drinking water standards listed in Table 9-1 are not considered to be <br />directly applicable to the alluvial monitoring wells or to groundwater in the underground void, because <br />these are not direct sources of drinking water supply." The WQCD disagrees with this statement and the <br />implications of this statement in the EPP. The Interim Narrative in Regulation No. 41 applies in this <br />instance, meaning that all the standards, including uranium, listed in Tables 1 through 4 in Regulation No. <br />41 apply at the point of compliance for the mine. For the Schartzwalder Mine, the groundwater point of <br />compliance, which has been determined by DRMS, is Ralston Creek at the lower property boundary. <br />Thus, the EPP needs to reflect that the domestic use groundwater standard for uranium of 30 ug/l does <br />apply the point of compliance. DRMS is obligated to implement that standard through their mine <br />reclamation permit. <br />Mitisation Options and Construction Schedule <br />Cotter presented three mitigation options in the EPP: constructed wetlands, a permeable reactive barrier, <br />and partial source removal. <br />The constructed wetlands and reactive permeable barrier are both passive treatment systems. The EPP <br />does not indicate that either of the treatment systems would result in water quality achieving the uranium <br />standard at a groundwater point of compliance or in surface water. The EPP should be revised to show <br />how the proposed mitigation options detailed in the EPP attain applicable water quality standards. <br />The EPP mitigation options include a discussion on page 15-10 of a partial source removal based upon <br />the decommissioning plan for the Radioactive Materials License (RML) termination. The EPP should <br />discuss this source removal in more detail. <br />The WQCD recommends that the EPP should include a mitigation option that contemplates complete <br />removal of the alluvial fill material coupled with active water collection and treatment of seeps, springs <br />and groundwater to assure attainment of water quality standards in Ralston Creek and at the groundwater <br />point of compliance. <br />The construction schedule for implementing a mitigation option in the EPP is vague. The construction <br />schedule should be revised to be more specific. Also, the implementation of a mitigation option must <br />attain water quality standards as soon as possible. <br />Drinking Water Concerns <br />Ralston Creek flows directly to Ralston Reservoir along with significant water flows from other sources. <br />Ralston Reservoir is a raw water supply for three public drinking water systems that serve large <br />populations. The uranium concentration in Ralston Creek significantly exceeds the water quality standard <br />for uranium. The three water treatment plants that use this water supply are capable of removing <br />uranium, however they are not specifically designed to do so. Additionally, the uranium level in the <br />material filtered out of the raw water will increase. The higher radioactivity level in this material could