2010-01-13_GENERAL DOCUMENTS - M1983083

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Colorado Division • of Reclamation, Project Mining & Safety Franklin Mine Bond Forfeiture Project, continued... Construction Summary Cont. Concrete associated with the Mill structure was pulverized and buried under 4 feet of fill material. . . , Once the structures were demolished and removed, the site was . ... backfilled and graded to blend in with the surrounding area. Backfilled slopes on the Mill area range from 2.5H:1 (near the historic Franklin waste rock dump) to 4H:1 V on the north end. Pond 4 water was pumped and used for dust suppression for demolition of the Mill. The Pond liner was cut and folded in • pieces and buried with the concrete rubble. The tailings material �`... removed from Pond 4 was amended with 120 tons of portland ;: cement and placed in the 0.6 acre footprint of tailings Pond 5. This was to reduce permeability of cover soils placed over the tailings material and reduce surface water infiltration into the • tailings material. Once the cement was mixed with the cover The upper portion of Gilson Gulch consist of boulder drop material, over two feet of clean overburden material was graded structures. High flow will spill over the concrete spillway into across Pond 5 to create 4H:1 V to 5H:1 V slopes. The Pond 5 the lower drainage channel. embankment slope was buttressed and reduced to 2H:1V. A spillway was constructed to allow storm water to safely • r discharge. ' -a q "t The Gilson Gulch Reconstruction Channel was designed to accommodate large storm events. The drainage plan utilized the existing drainage location to convey storm flows around the mine into existing culverts (C1). The drainage channel was excavated and lined with riprap and fifteen boulder drop structures. At the ; • access road culvert, flows split into two different channels. The . ti low base flows continue down the existing rock excavated . channel adjacent to the access road. High storm flows are s. \ --, . diverted through a concrete spillway constructed in the channel 411 adjacent to culvert Cl. The spillway discharges storm flows into • a newly constructed channel that conveys flows around Tailings Pond 5 where it reconnects with Gilson Gulch. Grading of the lower mine area and Tailings Pond 5. The lower drainage channel is comprised of grouted rip rap where it All disturbed areas were roughened, seeded, fertilized and connects back into Gilson Gulch mulched. The project was completed on October 20,2009. Change Orders Project Data, Change orders were issued to address additional tailings material Franklin Mine Bond Forfeiture Project:Reclamation of the discovered in Pond 4, portland cement material over Pond 5, Franklin Mine and Mill site using the forfeited reclamation bond buttressing Pond 5 and abandoning an illegal well. and State Severance Tax Funds Project Completed:October 20,2009 Future Monitoring and Maintenance The Franklin Mine site will be inspected annually until Total Project Cost: $533,159.95 vegetation has established and until the storm water permit is terminated.