_GENERAL DOCUMENTS - C1981017 (231)

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JUL-27-19910 13:23 ROPERT DELANEY 970 945 2303 P. 12 97-CV-131-3 07/21/98 Page 3 At the switchbacks below the Mine #3 bench (Figure 8), the material on the outslopes and cut slopes was observed to be very rocky, The surface material on the slopes is comprised of sandstone and shale material, best described as gravelly with cobbles. Very little plant growth was observed along these slopes, and the chances of establishing vegetation on these slopes are low. Road surfaces have vegetation growing, but even with heavy mulching and seeding, areas remain where growth is sparse. Along the north side of the Mine # 3 bench, there is fair revegetation on the bench and areas with gentle slopes (Figure 9). The dominant plant species on the bench was orchardgrass (85% relative cover). Kentucky bluegrass, western yarrow, and penstemon were also present on the bench. Plant growth on the backfill at the portals illustrates the same distribution as plants found on the native slopes. Plants are found on the moderate toe of the slope, and plant growth thins with increasing slope, until there are no plants found near the angle of repose slopes which comprise approximately the upper one-third of the slope. The north bench outslope of Mine # 3 is very steep and is composed of large rock material, iron, trommel screenings, coal, and waste (Figure 10). As can be seen in Figure 11, CDMG has established vegetation on the moderate bench at the top of the slope. Seeding and mulching occurred downslope with little success. No vegetation ,was established on the angle of repose slope at the top of the outslope. Some vegetation grew on the slightly moderated mid-slope, while no vegetation grew on the lower slope. The probability of successfully revegetating this entire slope is low. Silt fence installed at the bottom of the slope has been destroyed, presumably by soil creep and material flow. Above the lower bench cut slope of Mine #3, a number of aspen trees have been knocked down, possibly by snowslides or rockfall. This may indicate problems with tree establishment on these slopes. Mine #4 In 1997 CDMG conducted revegetation activities at the mine bench, outslopes, bin bench, toe of the mine bench outslope, and upper access road below the mine benches. Revegetation at the mine benches and cut and outslopes below the mine bench consisted s of mulching, seeding, and fertilizing. Plant growth along the road slopes was sparse and consisted of groundsel, curly dock, and a few wild strawberries. These are native species typical of disturbed areas. At the bin bench area CDMG has mulched and seeded approximately 75 feet down slope below the bench to the native trees. Growth from seeded plants was not evident on the outslope. As with other bench outslopes, the likelihood of satisfactorily revegetating this outslope is very low. The bin bench has revegetated fairly well. The dominant species is orchardgrass. Other species present include; American vetch, timothy, Lewis flax, Kentucky blue-grass, and Rocky Mountain penstemon.