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Rule 4.09.1(5) Slope protection shall be provided to minimize surface erosion at the site. Diversion <br />design shall conform with the requirements of 4.05.4. All disturbed areas, including diversion <br />ditches that are not riprapped, shall be vegetated upon completion of construction. <br />A suggested comment to the applicant is: Please include a detailed design of the fill structures. <br />Terraces are recommended (Colowyo has had success with this construction technique). If <br />terraces (benches) are utilized [see rule 4.14.2(2)], please consider no more than 50-foot rise in <br />elevation between benches to keep overland flow distances within reason, but Colowyo bas <br />successfully vegetated higher lifts in the Streeter fill. Please include description of any terraces <br />(back-slope, cross-slope, width, etc.). <br />Please include a design of upland diversion ditches (perhaps sequential). <br />Please include a design of perimeter relief drains (will almost certainly require riprap). <br />A description of sequential grading, placement of topsoil and seeding is recommended (a 50- <br />footlift protected before the addition of the next 50-foot lift). Included a schedule of work in <br />this design if a sequential schedule is proposed. For example, is there to be sequential stripping <br />of topsoil up the slope as the fill is constructed from the toe up? Is there to be sequential <br />construction of the valley fill drain? Is there to be sequential construction of perimeter relief <br />drains? <br />Rule 4.09.1(6) The disposal areas shall be located on the most moderately sloping and naturally <br />stable areas available as approved by the Division. Ifsuch placement provides additional stability <br />and prevents mass movement, fill materials suitable for disposal shall be placed upon or above a <br />natural terrace, bench, or berm. <br />The disposal azeas are not located on the most moderately sloping azeas, but the valley-fill option is <br />selected. <br />Rule 4.09.1(7) The excess spoil shall be transported and placed in horizontal lifts in a controlled <br />manner, concurrently compacted as necessary to ensure mass stability and prevent mass movement, <br />covered with topsoil or substitute material in accordance with 4.06, and graded to allow surface and <br />subsurface drainage to be compatible with the natural surroundings and ensure along-term static <br />safety factor of I.S. <br />The plan is for end-dump lifts, graded back to 3 horizontal to 1 vertical. The proposed work is <br />similar, and has been successful, at Streeter Fill (see Exhibit 12 of the PAP). A suggested comment <br />to the applicant is: Please include a description of crowns or cross-slopes, and back-slopes, <br />needed to manage surface drainage. Note that the application needs to demonstrate a factor of <br />safety of 1.5. Rule 4.09.1(7) Rule 4.09.2 (1) <br />Rule 4.09.1(8) The final configuration ofthe fill shall be suitable for postmining land uses approved <br />in accordance with 4.16, except that no impoundments shall be allowed on the completedfill. Small <br />depressions may be allowed by the Division ifthey are needed to retain moisture, minimize erosion, <br />4 <br />