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REPORT OF RECLAMATION ACTIVITIES, COAL BASIN MINE <br />1999 <br />The winter of 1998 / 1999 was characterized by relatively warm and dry conditions. <br />During a site visit in late February, 1999, only two feet of snow was observed at the Mine <br />1 area (elevation 10,000 feet). Heavy snows occurred during the spring , bringing the <br />total annual snow fall to near normal by early May. Rain occurred on a daily basis from <br />mid-July through early September, delaying construction activities. Little precipitation <br />occurred between mid-September and late November. This unusually extended dry <br />period may have a negative impact on fall seeding efforts. <br />GENERAL <br />The road from Redstone to Coal Basin was opened by April 5. About a foot of snow <br />covered the facilities area at that time. By April 29, most of the areas below the Rock <br />Tunnel area were snow free and accessible. <br />The Huntsman Project, completed in the fall of 1998, was the first reclaimed area to be <br />investigated in 1999. During reclamation construction, due to the length of the reclaimed <br />slope, it was apparent that a slope break was desirable. The reclamation contract <br />specified the construction of a ten feet wide, slightly inclined bench to address the slope <br />break concern. However, upon reflection, it was realized that snow accumulation and <br />differential melting of snow on bench slope breaks generally lead to their failure, <br />resulting in large gully development. This seems to be most prevalent on north facing <br />slopes. Therefore, dozer dips were created to act as slope breaks. <br />Hundreds of dozer dips were created by placing a light dozer at the toe of the reclaimed <br />fill slope. The dozer backed up the slope about ten to fifteen feet, dropped its blade and <br />pushed forward (downhill) until a mound of topsoil six to eight inches tall accumulated at <br />the blade. The dozer would then lift its blade and back up and repeat the process until it <br />reached the crest of the slope, where it would move to the side and proceed to the base of <br />the slope to start the process all over again. This occurred until the entire slope was <br />covered by these dips. <br />Observations made in early- to mid-May indicated that, for the most part, the dips <br />functioned as intended. In some areas where the vertical spacing was too great, the dips <br />had a tendency to drain at the edges, periodically forming small rills at these locations. <br />Overall, the height and horizontal spacing of the dips appeared to be adequate to prevent <br />significant gully formation. <br />One small slope failure was observed near the base of the slope. The topsoil and the <br />immediately underlying coal refuse apparently became super-saturated, and a small <br />rotational failure occurred. The failure is less than five feet across at its head, and less <br />than eighteen inches in depth. No drainage was observed from the failure zone, but it is <br />suspected that drainage from within the coal refuse was the primary contributing factor to <br />2