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Sub -grade Preparation <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 />The sub -grade preparation through 45mi1 line installation for the TSF is as follows: <br />1. Clear cut/log trees. Clear and grub organic matter including tree roots, pine needles, dead <br />wood and other deleterious materials. <br />2. Clear topsoil and place in topsoil stockpile for reclamation. <br />3. Cut and fill to design specifications using contractor selected equipment. Equipment can <br />include track dozer(s), backhoe(s), scraper(s), front end loader(s), road grader(s), sheep <br />foot compactor(s), or excavator(s). <br />4. Fill material will have top size of 6in and contain 50% silt and clay. <br />5. Fill will be placed in 10 -12in level lifts and compacted by a self - propelled sheep foot <br />roller. <br />6. Fill will be placed at 95% of Standard Proctor dry density (ASTM D 698). <br />7. Fill will be scarified between lifts. <br />8. Fill will be moisture conditioned to within 2% of optimum. <br />9. Construction engineer will be on site to provide testing during fill placement. <br />10. Verify compaction of floor of pond by number of tests recommended by CTL Thompson. <br />11. Install 12in of 1 x 10 cm/sec clay liner. Clay liner will be installed in two lifts, 6in each. <br />Clay will be compaction tested at one test per 2,500cy clay placed. <br />12. Install geomembrane wick drain leak detection grid within top layer of clay capable of <br />intercepting liquid within the leak detection zone and conveying the liquid to a collection <br />sump for storage. <br />13. Install leak collection sump and piping in pond comer and connect geomembrane wick <br />drain leak detection grid to the sump. <br />14. Lining contractor to install 45 mil reinforced Polypropylene. <br />15. Liner will be tested at intervals specified by manufacturer and contractor but not less than <br />two tests will be performed. <br />16. Materials or construction not meeting standards and design specifications will be <br />removed and repaired. <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. Fill material will have top size of 6in <br />and contain 50% silt and clay. Fill will be placed in 10 -12in level lifts and compacted by a self - <br />propelled sheep foot roller. Fill will be placed at 95% of Standard Proctor dry density (ASTM D <br />698). Fill will be scarified between lifts. Fill will be moisture conditioned to within 2% of <br />M1990 -057 September 27, 2011 <br />