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There is not currently an approved stability monitoring program with triggering levels in place for the <br />existing dams. However, piezometric levels are recorded, and field observations are noted and reported <br />as appropriate for corrective actions or engineering review. <br />Climax is developing operational plans for the Tenmile and Mayflower TSF dams, to be implemented as <br />tailing deposition resumes. Analyses are being completed to develop an understanding of the anticipated <br />changes in pore pressure conditions in the operational facilities and will identify key piezometric <br />elevations. These findings will be integrated into ongoing stability analyses. <br />As discussed in the Geotechnical Stability Exhibit presented in Permit Amendment AM -06, slope stability <br />evaluations of the TSF dams were completed in 2007. These analyses were updated in 2009 as part of <br />the feasibility study. The Engineer of Record for Climax is reviewing stability for start-up, and will <br />incorporate these analyses into the operations and monitoring and QA/QC program. The results of these <br />analyses for the Tenmile TSF (3 Dam) are nearing completion and Climax intends to submit a report and <br />monitoring plan to DRMS in January 2012. <br />- There is no mention of phreatic surface monitoring, inclinometers or any structural monument surveys of <br />these tailings dams in the EPP at this time. If this type of stability monitoring is not currently being conducted, <br />this topic will need to be addressed by Climax before full scale mining and processing resumes. Climax will <br />need to commit to submitting, and receiving DRMS approval, of a TSF Design, Operations and Monitoring <br />Plan before these facilities are further enlarged. The TSF plan and the annual report should include at least <br />annual stability monitoring /certification by a qualified engineer as well as the design and QA/QC plans for <br />TSFs. <br />Each of the TSF dams incorporate piezometers. Piezometric elevations are monitored in the inactive <br />dams typically on a weekly basis, with the data reviewed at least semi - annually by a qualified engineer <br />(Engineer of Record URS Corporation). The dams are inspected on an annual basis. The results of this <br />review are used to generate strategies for management of the tailing storage facilities or, in cases where <br />corrective action is needed, development of a corrective action plan. The dams do not include <br />inclinometers or movement monuments since there has been no reason or cause for inclinometers or <br />movement monuments to be installed. If physical observations or piezometric review indicated a <br />movement issue, Climax would evaluate and incorporate additional monitoring instrumentation, as <br />appropriate, in consultation with the Engineer of Record. <br />In addition, in accordance with the AM -06 approval stipulations, the annual hydrologic review to report <br />flood storage capacity will include pond level data for the TSFs and Robinson Lake collected throughout <br />the year to demonstrate that adequate flood storage capacity is maintained. This, along with the results <br />of TSF stability monitoring can be included in the annual report to DRMS. The design and QA/QC plans <br />are addressed in the previous response. <br />- Although obviously not part of the TSFss, what long term stability monitoring plans are in place for the open <br />pit itself? The annual report for this site should include at least an annual long -term stability <br />monitoring /certification by a qualified engineer. <br />Several monitoring systems are being employed to monitor the stability of the open pit, primarily as a <br />safety measure in support of operations. These systems include the following: <br />