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The Phase 1 liner in VLF2 will be completed to the HGM pad during the 2016 construction <br /> season. At that point the VLF2 and HGM liners will be welded together into a continuous <br /> collection system. <br /> I have consulted with both our Projects team who is responsible for the construction of the <br /> facilities in question and our Process group who operates the HGM and VLF2 to try and provide <br /> you with a fulsome response. Our conclusion was that the best way to illustrate the points <br /> contained in this letter is to provide you with the relevant design drawings of the HGM liner and <br /> sump and the Phase 1 liner connection to the HGM liner. Enclosed are two design packages <br /> labeled Mill IFC Drawings and 2. <br /> The HGM liner, engineered fill, and sump in the southeast corner of the HGM pad are illustrated <br /> on drawing A-170 in package 1. This design shows how the sump keeps the engineered fill on <br /> top of the liner from collecting water. It also shows the relationship of the top bench which has <br /> the HGM working surface and the second bench of select material that contains the liner. If <br /> water percolates through the top bench into the second it is collected by the sump. The drawing <br /> does not show the equipment berm along the edge of the top berm but it is shown in Drawing <br /> 320 sheet 3 in package 2. The berm will under some conditions also collect small amounts of <br /> surface runoff behind it, which may percolate under the berm and through the surface material on <br /> the top and 2nd benches and express itself on the surface. As you noted there are traces of <br /> oxidation on the surface of some of the upper berm material which is not uncommon with <br /> country rock from the district. <br /> VLF2 is designed with an underdrain system which collects any water that flows under the liner <br /> system. That system has been operational in 2015 and so any water that has come off the edges <br /> of the mill pad since commissioning of the system commenced will have been captured in the cut <br /> off trench below the VLF2 toe berm and pumped back into containment. <br /> The Phase 1 liner tie into the HGM liner is illustrated on Drawing 320 Sheet 3 in package 2. As <br /> indicated above this liner tie in between Phase 1 and the HGM will be made in the summer of <br /> 2016. This installation will complete the VLF2 containment system to the HGM pad, but as <br /> discussed above containment is already being achieved by the underdrain system. <br /> At our meeting on 22°d of February it was also agreed that CC&V would provide you with the <br /> specifications for steel header pipes being used within 15 feet of the edge of liner. Please find <br /> below the requested specifications provided the mechanical engineers in our projects group: <br /> All piping has been constructed in accordance with ASME B31.3 Process Piping Code <br /> requirements and testing procedures. <br /> • Pipeline `D' is 14"-BS-81826-3CB is a 14 inch pipeline that has an operating <br /> pressure of 355 psig and design pressure of 400 psig. <br /> • Pipeline `J' is 30"-BS-88002-3CB is a 30 inch pipeline that has an operating pressure <br /> of 358 psig and a design pressure of 400 psig. <br /> • Pipeline `K' is 30"-BS-88001-3CB is a 30 inch pipeline that has an operating <br /> pressure of 358 psig and a design pressure of 400 psig. <br />