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TSF Construction Preparation <br />Construction of the Phase 1 TSF impoundment requires the removal and replacement of <br />approximately 1,000st of historic tailings and approximately 100 tons of magnetite, both <br />currently contained within the unlined facility. The TSF OB stockpile to the east of the existing <br />impoundment will also be removed, incorporated into the fill construction of the lower access <br />road to the concentrate storage, fill for the Phase 1 impoundment and suitable clay underliner <br />material used for the Phase 1 pond bottom. <br />Following construction of the lower access road on the south side of the mill, a portion of this <br />road will have a 6 -8inch lift of suitable clay compacted as a pad for the temporary storage of the <br />historic tails and magnetite during construction of the TSF. Following pond construction, liner <br />installation, and overliner installation, the historic tails, magnetite, and clay pad will be placed <br />back in the Phase 1 TSF. <br />Timbering, stump removal, and topsoil removal will occur prior to disturbing additional lands. <br />The timbering and stump removal will be performed by local contractor with the timber removed <br />from the site. The topsoil will be removed in accordance with the topsoil plan and stored in the <br />existing topsoil storage pile. <br />TSF Stability Analysis and TSF Design <br />The existing tailings embankment will be removed and the Phase 1 TSF embankment will be <br />reconstructed as shown in Exhibit TSF -02. The compacted fill embankment has a 2.5:1 <br />(horizontal to vertical) outside face, and a 2:1 interior face. A 6 -8in clay under liner is placed on <br />the interior slopes and impoundment bottom, compacted as one lift with a sheepsfoot roller. The <br />clay material is selected from available onsite impermeable soils borrowed from the tailings <br />disposal area. <br />Following installation of the clay liner, a seepage /leak detection system between the clay layer <br />and the synthetic liner with the collection system located in the northwest corner of the <br />impoundment, and the impoundment bottom sloping at 1% slope to the northwest. <br />Following installation of the seepage /leak detection system, a synthetic pond liner of 45 -mil <br />Polypropylene Geomembrane or equivalent will be installed as shown in Exhibit TSF -04. <br />The impoundment liner will be held in place with material from the ore stockpiles discussed in <br />the ORE STOCKPILES section. The material may be directly placed as an approximate 6 -inch <br />overliner to hold and protect the Polypropylene Geomembrane liner, or placed in sand bags and <br />placed on the liner. Additionally, the existing on -site stockpiles will also be initial feed stock for <br />mill startup with the tailings reporting to the tailings facility. <br />CTL/Thompson, Inc. is currently conducting slope stability analysis on the TSF embankments as <br />shown in Exhibit TSF -02 and TSF -03. Samples have been collected from drilling two (2) <br />additional holes to verify and confirm the 1990 permeability test hole data and additionally <br />confirm the embankment materials and underlying soils. Additionally, a sample of tailings <br />materials generated from laboratory testing is being analyzed. The embankment materials, <br />native oils and tailings materials are being tested for strength and classification, using direct <br />shear tests for use in analyzing slope stability of the embankment. The results of the <br />CTL/Thompson study will be incorporated into the construction of the impoundments. <br />Phase 1 TSF reconstruction and Phase 2 new construction will use similar construction <br />techniques and methods. The Phase 3 expansion lifts, will additionally use typical cyclone <br />M1990 -057 June 6, 2011 <br />