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04-03-1996 14:00 303 447 2999 P.03 <br />Description of the Project - Reclamation Procedure <br />Regrading took take place using on-site materials. This <br />required excavation of the existing quarry floor to v2~.rying <br />degrees to produce enough loose material for grading. The bulk <br />of regrading was accomplished using Lyons and Fountain <br />formation rock from the pit floor. Slope was returned to near <br />its original angle (approx. 2(h): 1(v)). Following rough grading, <br />clay from the Lykins shale formation in the eastern side of the <br />pit was placed over the coarse rock surface as a subsoil <br />material (Figure 2). Since topsoil per se had not been salvaged <br />during mining, a substitute in the form of filter fines from the <br />City of Boulder Betasso Water Treatment Plant was examined. <br />This material was favorable in organic content (3%) and texture <br />(sandy loam), but, as a result of being filtered/flocculated and <br />dropped in .settling ponds, had no structure. A layer of filter <br />fines 3 to 6 inches thick was placed over the clay subsoil <br />material prior-to seeding (Figure 3). <br />In late November and early December, 1994, the buttrE:ss slope <br />area was seeded by hand and raked. Weyerhauser Soil (guard TM <br />bonded fiber matrix was then applied at the rate of 35()0 Ibs /ac. <br />Some of the material was applied over approximately one inch <br />of fresh snow. Some of the areas less steep than the 2 :1 <br />buttress slope that had been topsoiled were also seeded and <br />treated with conventional hydromulch in 1994. The rernainder of <br />the quarry area not seeded in 1994 was seeded in fall 1995. <br />