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Site Observations <br />The winter of 2000 / 2001 was characterized by fairly normal weather patterns, following <br />a dry fall. Spring run off was relatively benign, with snow coming off slowly and evenly. <br />No acute flow events were observed to have occurred in either Coal or Dutch Creeks <br />during the runoff. <br />Reclamation work completed prior to 2000 weathered the runoff well. Excepting a small <br />portion of the Bear Creek Project Area, little, if any, significant erosion was observed on <br />the previously reclaimed areas. A half dozen or so small gullies had developed on the <br />north facing slope. of the Bear Creek portion of the Old Refuse Pile. These gullies, <br />which averaged about 150 feet in length, six inches in depth and ten inches in width, <br />appear to have developed as a result of the failure of some of the hummocks created <br />during reclamation construction. The constructed dips were adequately sized, however <br />a few above the head of the gully overflowed, causing a cascading effect of water <br />downslope, resulting in a concentrated, high velocity flow system. It is thought that the <br />hummocks as constructed were sufficiently sized to prevent this type of flow system <br />from developing. However, the area was heavily grazed in 2000, the first year following <br />reclamation construction. It is theorized that the action of the cattle hooves sufficiently <br />diminished the size of some hummocks in this area resulting in water flow around the <br />sides of the affected hummocks. This lead to the development of water cascading from <br />one hummock to the next, overwhelming each in succession, resulting in gully <br />formation. <br />In 2000, the majority of the sediment ponds on the site were reclaimed by removing the <br />corrugated metal dewatering devices, constructing an open, armored spillway at each, <br />and revegetating the area surrounding each pond from the low water line to <br />approximately ten feet above the high water line with a wetland seed mixture. Willow <br />cuttings were also planted at the water. line near the embankment of each pond. As a <br />result of previous reclamation projects, the contributing area for most ponds has been <br />significantly reduced, so that the volume of water being handled is much less than what <br />the ponds were designed to hold. <br />All of the ponds were observed to be in good condition in the spring and summer of <br />2001. The armored open spillways appear to have functioned as designed, as erosion <br />of the spillways was not observed. The willow plantings were not as successful as was <br />anticipated. It is estimated that less than thirty percent of the willow cuttings survived to <br />produce new growth during the 2001 growing season. <br />Roads B, C, and D which provide access to Mines 1, 2, and 4, were reclaimed in 2000. <br />Reclamation consisted of removing the corrugated metal pipe culverts which pass under <br />the roads at various locations, grading the road surfaces so that the road prism is <br />angled at approximately ten percent from the cut, or inside, margin of the road toward <br />the fill, or outside margin of the road. Numerous drainage dips and low water crossings <br />were constructed to transport surface water across the reclaimed road surface. The <br />2 <br />