2011-12-15_REVISION - M1977493 (2)

Home Browse Search

Technical Revision (TR -18) Climax Molybdenum Company Environmental Protection Plan Permit No. M- 1977 -493 Eagle River basin is classified as Aquatic Life Cold 1, Recreation E, Water Supply, and Agriculture. Tenmile Creek, which begins a the CPDES permitted outfall for the Site is designated by the Water Quality Control Commission (WQCC Regulation 33) as Segment 13 of the Blue River basin; the mainstem of Tenmile Creek from the Climax Parshall Flume (Outfall 001) to the point immediately above the confluence of West Tenmile Creek. Segment 13 of the Blue River basin is classified as Aquatic Life Cold 1, Recreation P, and Agriculture. Water Quality Standards for each of these stream segments, as identified in the current versions of the above referenced WQCC Regulations, are presented in Table T -4. Before Climax implemented its current water treatment/management system, there was a near complete absence of stream life in Tenmile Creek upstream of its confluence with West Fork Tenmile Creek near Copper Mountain. These conditions were attributable primarily to acid mine drainage from historic mining activity within the headwaters area of Tenmile Creek. Over the past 40 years, Climax has implemented a water treatment/management system in the Tenmile headwaters area, which has included reclamation of many historic mining sites, and capture and treatment of impacted waters from many inactive mines in the drainage area. Since Climax has implemented its water treatment/management scheme, Tenmile Creek has recovered to support a viable and reproducing fishery downstream from the point of the Climax outfall. The complete responsibility accepted by Climax for water treatment/management within the headwaters area of Tenmile Creek is reflected in the Water Quality Control Commission's 1987 rulemaking regarding the Climax outfall, in which the Commission stated: The evidence in these proceedings on Ten Mile Creek have shown that Ten Mile Creek for all intents and purposes begins at the Climax property boundary at a place designated as the Parshall Flume." It is at this point that the natural flows that are intercepted by Climax in the Ten Mile Creek Basin are channeled together and form the source of Ten Mile Creek. Hence the Commission believes Parshall Flume to be the source of the mainstem of Ten Mile Creek. Also included in this segment are all tributaries to Ten Mile Creek including those natural tributaries intercepted by Climax. (5 CCR 1002 -33.11 & 33.16) Storm water management information for the Climax Mine site is discussed throughout this EPP. Storm water is managed in accordance with Storm Water Permit COR- 040178. T -8 Water Quality Monitoring Plan As discussed previously, a Groundwater Monitoring Plan for the Climax Mine was previously submitted to DRMS as TR -08 in September 1995. That plan included monitoring locations and a monitoring schedule, which has been followed since that time. An updated Water Quality Monitoring Plan is included in the Environmental Protection Plan as Appendix T -C. This current plan expands upon the previous plan and includes additional points of compliance, identifies appropriate standards, and includes intemal monitoring locations upgradient of Clinton Reservoir and Eagle Park Reservoir. This monitoring program is intended to provide data for: (1) demonstrating that EPP requirements are being met; and (2) evaluating changes in water quality that may be related to mining and milling operations at the site. It also provides a process for identifying when changes may be occurring so that appropriate actions can be taken to prevent adverse off -site impacts. EPP: Version R2 T -35 December 2011