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Chapter II <br />As recommended by Golder & Assoc. in reviewing the Phase II sediment pond <br />• designs, special care is taken with the cleaning and maintenance of the Sutey area <br />ponds and appurtenant structures. <br />(4) Sutey -Reclamation. <br />Permanent slopes of the pile will be reclaimed by final grading, topsoil placement <br />and revegetation. <br />Varying depths of topsoil will be distributed on the permanent slopes, placed <br />according to aspect, with 12-18 inches on north and east slopes, 18 to 24 inches on <br />west and 24 to 30 inches on the south slopes. <br />Seeding and planting of permanent slopes will be done during the first normal <br />period for favorable planting (normally late fall --October and November). The <br />special Sutey mix will be broadcast seeded at 30 Ibs/acre. <br />Suitable mulch and/or other soil stabilizing practices will be used promptly, with <br />straw mulch broadcast at 1-1/2 to 2 tons per acre on all regraded and topsoiled <br />areas to reduce erosion and promote germination of seeds. <br />b. Old Pile. <br />From 1961 until late in 1984 coal refuse was deposited at a site just east of the <br />preparation plant and adjacent to Coal Creek. By the time it was closed in 1984, <br />approximately 2 million cubic yards of coal waste had been deposited at this site, <br />with a maximum height of approximately 180'. <br />An extensive study of the facility was done in 1977 by Morrison-Knudsen. Another <br />was done in 1984, last year during which it was in active use, by Geo-Hydro (see <br />App. II-B-7). <br />As noted in these studies, characteristics of the refuse pile and construction include: <br />- The M-K study evaluated the coal refuse and its <br />physical properties, and a series of stability analyses <br />was performed to verrfy the stability of the existing <br />piles and to estimate the stability of the future facility <br />extensions or the stability of a new facility. <br />- The coal refuse material can be classfied as <br />well-graded, silty gravel (GM) in accordance with the <br />Unfied Soil Classification System. <br />:~ <br />42 <br />