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14. There is no discussion of the method of sealing against leaks at the points where the <br />conveyance pipes enter the mine water pond or the outlet pipes exits the pond. Please <br />provide that information and show on a diagram if needed. <br />As stated above, the installation of the Pipe Boots will be conducted by a technician from <br />Colorado Lining International or a qualified person on site. Appendix 12 also discusses <br />the installation of the Pipe Boot seals. <br />15. Please provide details about the bedding materials to be used in the trench for the pipes <br />running between the leach field and the mine water pond. <br />The bedding material (sand) has been discussed in Appendix 12 and also is shown in <br />detail on Map G -12. <br />16. The later phases of the operation will include disposal of waste rock above the initial <br />rock cap of the leach field. Map C -3 indicates that an additional vertical 17 feet of rock <br />may be placed on it, and Map C -4 depicts topsoil storage on the western end of the <br />leach field. Please describe how the weight of additional material and the equipment to <br />move it will not destabilize or damage the integrity of the liner or rock layers. <br />The subsection titled "HPDE Pipe Stability" in Appendix 12 addresses the pipe stability. <br />The stability of the liners has been addressed by adding a geocomposite layer on both <br />sides of the reinforced polypropylene liner. <br />17. Please discuss how potential leaks in the liners and /or pipes will be detected, and how <br />they will be repaired. If leak detection is not a concern, please explain why. <br />A leak detection company will be hired to evaluate the liners after installation. Additional <br />measures to be taken are described in Appendix 12 - Leach Field Design. Any leaks <br />detected will be repaired immediately using the heat fusion procedures by a certified <br />technician. Flow measuring devices are also installed at the portal and at the discharge <br />of the water to Sneffels Creek. If these measurements show a 15% difference and they <br />cannot be accounted for through evaporation or other means, a dye based test will be <br />used, as described in Appendix 12. Any leaks identified will be evaluated in consultation <br />with the Division. <br />18. As the mine water pond fills, which of the outlet structures will be the primary one to be <br />used: the buried pipe or the surface channel? <br />The surface channel is the only outlet structure. The buried pipe will only be used <br />for dewatering the pond for maintenance purposes. The spillway is discussed in <br />Appendix 12 - Mine Water Pond Hydrology. <br />19. The inlet and outlet pipes of the mine water pond will be installed at the bottom of the <br />pond, yet both include valves to be operated presumably from above the water surface. <br />Please provide additional details about the (submerged) valves on the inlet and outlet <br />pipes of the mine water pond. <br />Submerged /buried valves will be located at the dewatering pipe and gathering pipe <br />entrance into the mine water pond. These valves will have valve controls located above <br />5 <br />