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wells in the Arkansas River Watershed and proximate to the Overburden Storage Facilities, in particular <br />the McNulty Gulch area, has also been addressed in the revised WQMP. <br />- There is a strong connection between alluvial groundwater and surface water on this site, with alluvial <br />groundwater certainly discharging directly to surface water in these three drainage basins via the groundwater <br />to surface water pathway. The surface water in these basins is classified as "Aquatic Life Cold 1" among other <br />uses. The Division acknowledges that Tenmile surface water drainage is managed by a CDPHE Colorado <br />Discharge Permit System (CDPS) permit; however this is not the case for the Arkansas River and East Fork <br />Eagle River drainages at this time. As required by 6.4.21(11)(a) in the Hard Rock/Metal Mining Rule, please <br />provide the receiving stream standards and any existing surface water quality and flow data for the Eagle and <br />Arkansas drainages upstream and downstream of site activities. The rule requires "a minimum of 5 <br />successive quarters and such other additional data, or a period specified by the Office, as may be necessary <br />to adequately characterize baseline conditions." Please review sections 6.4.21(11)(a), (b) and (c) and address <br />as appropriate. <br />As referenced in previous responses, surface water quality data in the Arkansas River and in the East <br />Fork Eagle River (upstream and downstream of site activities) are available, and baseline conditions have <br />already been established. These data are included in Appendix A to the revised WQMP. Section T -7 <br />(Surface Water) of the EPP has been revised to reference this data and to incorporate a discussion of <br />stream standards. <br />The Division believes that surface water monitoring both up- gradient of mining activity (background) and near <br />the permit boundary down - gradient of the site should be conducted in the Eagle River and Arkansas River <br />Basins. This will enable Climax and the Division to establish background conditions for these drainages, <br />monitor for changes over time, and help determine if any observed changes may be attributable to site activity <br />or groundwater to surface water discharge. It will need to be determined what "background/baseline" <br />concentrations are in these drainages for analytes of concern (such as zinc and copper), and how this <br />compares to data from downstream of the site. Analytical methods used for surface water analysis will need <br />to be able to report sufficiently low detection levels to compare to surface water aquatic life standards. Please <br />address. <br />Climax has incorporated surface water monitoring at previously established monitoring locations in the <br />Arkansas and East Fork Eagle River in the revised WQMP. <br />- The Division will require for all monitoring points at least 5 quarters of full Target Analyte List (TAL) dissolved <br />metals (including Hg), total and WAD cyanide, SO4, HCO3, NO3 +NO2, F, CI, TOC, hardness, and total <br />alkalinity. Please update Section 6.0 accordingly. This list may be evaluated and reduced after at least 5 full <br />quarters of data have been collected and evaluated for all monitoring points. <br />Climax has expanded the analytical parameter list for baseline monitoring in the revised WQMP. <br />- NPL for WAD cyanide will be 0.2 mg/L or less for all groundwater monitoring points. <br />WAD cyanide has been included in the analytical list for baseline monitoring. As discussed in the WQMP, <br />Climax has not identified cyanide as an indicator parameter for which an NPL would be required, based <br />11 <br />