2011-09-27_REVISION - M1990057 (10)

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The following information regarding, Phase 2 and Phase 3 TSF facilities, is provided as additional information to enhance the reader's understanding of the project. As these future plans are formalized, UMC commits to submitting appropriate documents for approval of Phase 2 and Phase 3 TSF operations. Phase 2 TSF expansion be constructed and operational prior to the Phase 1 TSF elevation reaching 9722 ft. Following reconstruction of the lower access road on the south side of the mill, a portion of this road will have a minimum 12in lift, placed as two -6in lifts, of suitable clay compacted as a pad for the temporary storage of the historic tails and magnetite during construction of the TSF. This existing road will be reconstructed to a level road at elevation 9725ft, which is the crest of the Phase 1 TSF embankment, and the foundation of the mill. The south side of the road will have a berm (Jersey barriers) to prevent vehicles, delivery trucks from driving off the road or onto the TSF embankment. The road will be sloped at 2 to 3% to the south and graded to ensure south road surface water runoff reports to the TSF. The berm (Jersey barriers) will assist in controlling the runoff flow and directing runoff to the TSF. The road will be widened to allow passage around the new thickener at the southeast corner of the mill building. The road, during TSF construction, will be a minimum of 40ft wide with a 25ft turning radius at the southwest corner of the building. The road will built in lifts in accordance with Lake County driveway standards, using both the overburden stockpiled from the previous (existing) TSF construction and the excess cut material generated from the TSF construction. The road is shown on TSF 02. The temporary clay pad, for the temporary storage of the historic tails and magnetite during construction of the TSF, will require an area approximately 30ft by 250ft for a 5ft high storage pile, with 3:1 slopes. This storage area is within the disturbed area, on the reconstructed south road. The pile will be between the new concentrate storage room and the old septic tank, allowing minimal 8 -10ft wide access to the lower portion of the mill on the north side of the road during material storage. The storage pad is shown on TSF 02. In the event construction ceases for an extended period of time (winter shutdown) while the historic tails and magnetite are temporarily stored on the clay pad, the material will be surrounded by silt fence, bermed, and covered with visqueen for the interim construction cessation. M1990 -057 September 27, 2011