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C b. Back-pressure valves are suggested for inclusion as a safety feature in the solution pipelines. c. It is unclear whether the barren solution pipeline will run from the mill to the barren pond or if the pipeline will run from the mill directly to the top of the heap. Please clarify. 32. The pad solution collection trench shown on Exhibit C-8 does not appear to be the same as the series of collection trenches constructed through Stages 1-6 as illustrated in this section. Please clarify. 33. It will be necessary to provide a statement certifying that each particular phase of the leach pad (including primary and secondary liners) was constructed to the specifications approved by the Board. This statement must be submitted at the completion of each corstruction stage. In particular, test results on liner seaming and collection channel connections between stages should be presented after completion. Please commit to these submittals. 34. Figure C-9 and Figure C-10, Detail 11, specify that a facility pipeline corridor exists along the south and east heap perimeter, but does not identify the extent of the corridor. Please address whether it extends around the entire heap perimeter; where the pregnant delivery pipe and barren return pipes are routed; where these pipes enter the mill facility; etc. 35. Sections E-E'and F-F'illustrated on Figure C-9 do not illustrate the inclusion of the facility pipeline corridor to/from the pond/mill facilities. Please include. 36. The Typical Section of Perimeter Berm and facility pipeline corridor, Detail 11, Figure C-10, does not illustrate a secondary recovery layer on the heap side of the berm. Please include. 37. Figure C-10, Detail 6, illustrates the Plan of Secondary Recov?ry/Leak Detection System and Riser Pipe for Secondary Recovery/Leak Detection Sumps. Please discuss whether this system networks under the entire heap, or whether it is centralized within the heap, and whethe• there is more than one Leak Detection Sump. Section D.7.4.2 Process Solution Ponds 38. The design parameters for sizing the pond capacity as stated a~•e appropriate. A comparison to the water balance simulation provided in Appendix G shows the 52 acre-feet capacity to be exceeded at times by the combination of draindown (varies from 24 to 28 ac-ft) and 100-year storm (varies from 24 to 41 ac-ft). In order to support the design principal for containment, please submit either a revised pond capacity volume or model documentation which indicates sufficient pond capacity will be provided. -6-