2003-10-24_REVISION - M1986076 (2)

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Tailings IDisposal Bench [Is the depressed azea where all dumped tails will be confined] Yes, when it's full the currently approved site for tails will be re-utilized, as per the current plan. [The stacking or vertical placement of the disposed tailings is not clearly explained. Please describe the configuration of the lifts of tailings material to be placed on the bench, whether they will be placed against the cut wall, and how close to the bench margin (the top of the outer fill slopes) they will be placed] --~ The tails will be placed against the cut wall. The tails will be placed in the cut to a depth of 2', at which time 2' of soil, gravel, (approximately 15%) and larger rocks (approximately 35%) will be placed upon the tails and mixed by compaction, by a backhoe, with a minimum of at least 4 passes and or complete mixing and compaction are obtained. The 2' lifts are approximately the height of a dumped bucket of tails, they will be dumped across the bottom, end to end, until the length of the pond is full, then the soil and rocks, 2' will be added mixed and compacted. Before a new 2' lift is started, the surface will be roughned to assure good bonding. The tails will be stacked up to within 1' of the top of the lowest part of the pond. The last 1' to be compacted topsoil and small waste rack, until the permeablity is 106 cm/sec., or less. Leaving a slight depression across the top, the east and west ends will be sloped lower than the middle section of the pond, to help water to run off of the azea. This will be covered by a 5' cap of waste rock, mostly lazger size, and some soils, until the cover matches the surrounding countures 320-340. Which is the same, as the current reclamation plan calls for. I'm committing to upholding the conditions previously set forth in the file. Tailin~,s Material to be Blended [Ifyou are simply committing to make your tailings conform to the conditions previously set forth in the file (in the DMG letter), please provide a statement clarifying this] I am committing to make the tailings conform to the conditions previously set forth is the file. Permeability of Cap Above Tailings [Please verify whether you intended to state that eazlier permeability rate, or if you intended a different rate.] The permeability rate should be read 106 cm/sec., instead of 10. Tailings Disposal Bench-Phased Expansion [The drowings of the initial tailings disposal bench include a possible expansion to the east. I f the initial tailings area is filled (assuming tailings materaial has been stacked high)and art expansion is needed, how will you gain access to that azea? Please describe how and when an expansion may be constructed. Across section diagram would be valuable in your response.] Access to the proposed exapansion azea will be across the filled pond. The 5' cap would be left off until the exppnsion is filled. The material from the expansion will be placed against the cut wail, of the already filled pond for 4' to 5' outward, thus starting the 5` cover. This will still leave plenty of room for an access road to the expansion azea on the outside of the bench. Once the expansion area is full, then the rest of the 5' cap will be put on. I doubt that the expansion area will be needed so, it would be built at the end of filling the first stage of the pond, perhaps 2-3 yeazs, 2005.