2018-05-11_REVISION - M1977493 (2)

Home Browse Search

Water Quality Monitonng Plan Climax Molybdenum Company Version:R4 Permit No. M-1977-493 Table 3-1 -Summary of Field Hydraulic Conductivity Tests Hydraulic Conductivity Range Unit (ft/yr) Alluvium 2,595—88,378 Glacial Till 22—1,238 Paleozoic Sedimentary Bedrock 0—596 Tertiary Quartz Monzonite Bedrock 18—54 These field hydraulic conductivity test data indicate that the alluvium and glacial till in the Tenmile drainage are significantly more permeable than the bedrock units. By comparison, the bedrock units are of relatively low permeability and are not capable of transporting significant quantities of groundwater. 3.3.5 Groundwater Monitoring Sites 3.3.5.1 POC Groundwater Monitoring Site Climax uses well GW#2 as a shallow POC monitoring well for the Tenmile basin. This well is completed in the Tenmile Creek Alluvium and is considered representative of shallow groundwater downgradient of the tailing facilities that may ultimately recharge Tenmile Creek. GW#2 was constructed in 1987 and its location is illustrated on Figure 4. Climax also constructed bedrock well TM-MW-002D adjacent to GW#2 in 2012 as a second, deeper POC well, to monitor both shallow and deeper hydro-stratigraphic units. The well logs for GW#2 and TM-MW-002D are in Appendix A. Monitoring parameters and schedule are in Section 4 and data evaluation procedures are described in Section 5 of this WQMP. Water quality monitoring data which have been submitted in Annual Reports to DRMS are included in Appendix B-3. 3.3.5.2 Internal Groundwater Monitoring Site Climax uses well GW#1 as an internal monitoring site downgradient of the Mayflower TSF and upgradient of the POC wells(Figure 4). Climax constructed bedrock well TM-MW-001 D adjacent to GW#1 during 2012 to monitor both shallow and deeper hydrostratigraphic units. Monitoring parameters and schedule are in Section 4 and data evaluation procedures related to these internal monitoring sites are described in Section 5 of this WQMP. Water quality monitoring data which have been submitted in Annual Reports to DRMS are included in Appendix B-3. 3.3.6 Surface Water Monitoring Sites 3.3.6.1 Tenmile Creek Surface Water Monitoring Site The Climax water management and treatment system discharges treated water into Tenmile Creek at Outfalls 001A and 002A under CDPS permit. C00000248. Surface water sampling at the outfalls is performed in accordance with this permit, and is not included in this WQMP. Historical and current compliance with CDPS permit discharge requirements demonstrates the overall effectiveness of the collection and treatment facilities. 3.3.6.2 Internal Surface Water Monitoring Sites As discussed in Section 6.1, Climax has two internal surface water monitoring locations above Clinton Reservoir. The first monitoring site is located in upper Clinton Creek (CC-SW1) above its confluence with EPP-Appendix C May 2018 10