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Mr. Peter V. O'C .nor <br />Page 2 <br />September 23, 19115 <br />removal of this waste rock from these two mines' waste dumps will <br />result in a beneficial reduction in slope gradient, and help to <br />achieve water runoff control and promote voluntary revegetation. <br />The rock capillary barrier will be placed on the sloping sides of the <br />tailings dam within two years after the deposition of mill tailings <br />has ended. This will allow the upper outer edge of the tailings pond <br />to physically stabilize, and permit the use of a small dump truck <br />and conventional tractor to deposit the rock capillary barrier in an <br />even manner. After smoothing out as many surface irregularities es <br />possible, any of the fine overburden material that has been salvaged <br />from the topsoil will be placed over the rock capillary barrier. A <br />wood fiber mulch and appropriate soil amendments and fertilizers <br />may be used to increase potential plant growth medium if sufficient <br />fine overburden material cannot be obtained from the topsoil to <br />provide a 3 or 4 inch layer. Then, the three sloping sides of the <br />tailings retention structure will be covered by a 3 to 4 inch layer <br />of the stockpiled topsoil. Fertilizers will be incorporated into the <br />topsoil by raking and harrowing, which will produce a uniform seed- <br />bed. Nitrogen, phosphorous, and potassium will be applied during <br />this final preparatory work. A seed mixture containing both native <br />grasses and introduced species will then be planted at the rate of <br />around 40 pounds per acre by hydroseeding, or by employing a <br />Brillion grass seeder. Finally, a wood fiber mulch will be spread <br />over the embankment to control wind and water erosion and to <br />assist in retaining moisture during grass seed germination. <br />Once the former tailings pond area has physically stabilized, the <br />surface will be leveled by grading it with a small tractor. A rock <br />capillary barrier will then be installed by using a dump truck to <br />deposit it, and a small tractor to spread the waste rock over the <br />surface to a minimum depth of two feet. As many surface irregu- <br />larities as possible will be smoothed out, and any of the tine over- <br />burden that has been salvaged from the topsoil will be placed over <br />the rock capillary barrier. N order to obtain a 4 or 5 inch layer of <br />material prior to placing the stockpiled topsoil on this area, a mix- <br />ture of organic fertilizer and wood fiber mulch will be added to <br />this fine overburden. The organic fertilizer will supply nutrients and <br />the wood fiber mulch will increase moisture retention capability. A <br />2 to 3 inch layer of topsoil will be placed upon this prepared sur- <br />face, and additional nitrogen, phosphorous, and potassium will be <br />applied and incorporated by raking and harrowing. This preparatory <br />ground work will create a properly conditioned environment for <br />rapid seed germination. The same seed mixture of both native <br />grasses and introduced species that will be planted on the three <br />sloping sides of the tailings embankment will be used on the former <br />tailings pond. The seed mixture will be planted at the rate of about <br />40 pounds per acre by hydroseeding. A Brillion grass seeder may <br />also be used on this part of the tailings impoundment area. A wood <br />fiber mulch will be used to protect the seedbed from wind and <br />water erosion, and to promote better root growth. <br />