2011-11-02_REVISION - M1980244 (7)

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Mr. Berhan Keffelew, DRMS August 30, 2011 Page 2 small, pregnant solution head tank ( "Preg Tank ") ahead of the ADR in separate lines; the combined pregnant solution mixture then flows through the ADR. Barren solution exiting the ADR is pumped back to the VLF. The PSE circuit is being added to the processing circuit at CC &V to remove a persistent accumulation of precipitate solids in process solution from the VLF operations and improve targeted flow rates through the ADR and improve gold recovery from the process solution. A portion of the process solution from the VLF will be directed to the PSE circuit and then through the ADR facilities as currently designed and approved under Amendment No.9. The PSE circuit has been conceptually developed as a method, using basic coagulation/sedimentation processes, that stabilizes and clarifies the barren solution. Once operational, in addition to increasing gold recovery, the PSE circuit will allow for more sustainable and even distribution of barren solution on the VLF. The PSE circuit liner containment system will be installed per specifications outlined in Amendment No. 9 for clay and geosynthetic liner installation as an area for ore storage on the VLF. AMEC has prepared a design for the PSE circuit liner containment system (attached), that describes a geosynthetic component that will overlay a one (1) foot layer of Soil Liner Fill ( "SLF "), and be overlain by a two (2) foot layer of Drain Cover Fill ( "DCF "). The geosynthetic component consists of 80 mil, single- sided, textured, Linear Low Density Polyethylene ( "LLDPE ") with the textured side placed down, installed by a qualified liner contractor under the same specifications used on the VLF. Please also refer to the following attached AMEC drawings for additional details: • Drawing # A100 — Proposed Liner Grading Plan • Drawing # A105 — Proposed Liner Grading Isopach • Drawing # A110 - Proposed Final Grading Plan • Drawing # A115 — Proposed Final Grading Isopach • Drawing # Al20 — Typical Sections • Drawing # Al25 — Typical Details. Construction quality assurance will be provided by AMEC. An as -built and certification report will be submitted to DRMS in a timely manner upon completion of the project. Please note that the above -grade features generically depicted in Drawing # A110 are not necessarily in final form or position. Additionally, as depicted in Drawing # Al20 and Al25, spent ore will be placed above the DCF at varying depths to bring elevations to final grades as shown in Drawing #A110. CC &V is providing an updated Drawing C -4 (Proposed Facilities Overburden and Mines) to address the location of the PSE circuit lined facility within the Amendment No. 9 permitted area. The location of the PSE circuit lined facility within the disturbance area of the ADR facilities and comprises approximately 3.1 acre.