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Exhibit U /Section (10) Comment 2: Have the specifications /processes for the increase in dam <br />height for the Mayflower and Tenmile Dams been certified by a licensed professional engineer? <br />If so, have these designs been reviewed and approved by a qualified independent third party? <br />Response: Design and operating elements for the Mayflower TSF have been reviewed and <br />certified by a third party consultant /P.E. (URS Corporation). <br />Exhibit U /Section (16) Comment: Describe QA /QC program and measures to be employed <br />during construction of EPFs - What QA /QC processes are in place to ensure that the TSF dams <br />and OSF are constructed and maintained according to specifications? See also stability <br />monitoring comment for Rule 6.5(4). <br />Response: QA/QC processes for the Mayflower and Tenmile TSFs are incorporated into the <br />operating, maintenance and monitoring text and procedures of the attached Operations and <br />Maintenance (O &M) Manuals. <br />Rule 6.5 Comment 2: What is the monitoring /documentation program that has been <br />implemented to monitor for stability issues that may occur in the OSF and TSF dams during <br />construction, operation and maintenance (phreatic surface monitoring, permanent <br />inclinometers, etc)? This monitoring /documentation protocol should be clearly specified, and <br />will be included as an enforceable condition of the permit when approved. <br />Response: The monitoring programs for the Mayflower and Tenmile TSFs are described in the <br />attached O &M Manuals. <br />Rule 6.5 Comment 3: The introduction of the Geotechnical Stability Exhibit submitted with AM- <br />06 states that the information submitted is a preliminary overview, and that the design at this <br />time is not considered final. Obviously the long -term stability of the OSF and TSFfeatures is a <br />primary concern of the Division. While the preliminary evaluations appear in order, DRMS does <br />not review /approve 'preliminary designs" and will therefore require final design specification <br />evaluation and approval before the site resumes mining and additional material is placed in the <br />existing TSF or OSF facilities. Please consolidate and provide the CPT and laboratory data <br />protocols and reporting referenced and used in the preliminary design modeling. Also, when <br />submitting the final design specifications and evaluations, complete dynamic loading analysis for <br />the TSFfeatures will be required. These final design specifications and stability evaluations may <br />be subject to third party review as outlined in Rule 7.4.3. <br />Response: The attached Seepage and Stability Analyses report provides site investigation <br />information and third party design and stability analyses for the Mayflower TSF. <br />Specific DRMS comments in the September 9, 2011 DRMS adequacy determination letter for <br />TR -18 addressed by TR -23 are as follows: <br />Tailings Storage Facilities (TSFs) <br />- What types of stability monitoring are done on tailings dams 1, 3 and 5? Is there an approved <br />stability monitoring program with trigger levels and potential corrective actions currently in <br />2 <br />