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regraded roads were then severely ripped using a dozer, followed by fertilizer, seed and <br />mulch. <br />The roads weathered the spring runoff fairly well. Road C, which provides access from <br />Dutch Creek to Mine 4, suffered virtually no erosion damage. The dips and low water <br />crossings were spaced appropriately, and were adequately sized to accommodate the <br />snow melt runoff. Dip spacing was very tight at the upper portion of the road as it <br />approaches Mine 4. The close spacing was necessary as the road switchbacks steeply <br />in this area, thus concentrating drainage at the lower portions of the switchbacks. This <br />tight spacing worked extremely well in effectively handling the volume of water crossing <br />the road surfaces. <br />Road D accesses Mines 1 and 2 from the bottom of Road C near Dutch Creek, <br />approximately one mile west of the Lamphouse. The upper portion of Road D, <br />approximately one mile in length, did- not suffer any erosion damage. The middle to <br />lower portions of the road suffered minor erosion damage, primarily as a result of <br />constructing slightly undersized drainage dips in 2000. It was observed that the dips <br />had sufficient capacity to convey the volume of flow, but the base of some of the dips <br />was not wide enough to accommodate the velocity of the flow. The narrow base of <br />these dips tended to concentrate energy, allowing the flows to slightly incise themselves <br />at these locations. In two instances, it was observed that additional drainage dips were <br />needed, as a result of unforeseen water contributions from upslope areas. <br />Road B is an approximately one mile long road segment which provides access from <br />the Lamphouse to the intersection of Roads C and D. Road B suffered the most <br />damage during the spring runoff. Although minor in extent, erosion was more <br />pronounced on this road. This occurred because the road is situated at the base of a <br />south facing slope at about the elevation of Dutch Creek. As a result, it has a very <br />significant contributing area. Further, the cut slope of the road is host to many seasonal <br />springs and seeps. In some areas, the density of drainage dips was insufficient to <br />accommodate the number of seasonal cross flow sources which develop during the <br />spring. In another area, the dips were undersized to handle the velocity of the flow. <br />This resulted in down cutting of the base of the drains, and subsequent deposition of <br />sediment below the dip outlets. <br />Approximately 18,000 trees were planted in Coal Basin in 2000. All but about 1,500 <br />were planted by a contractor at previously reclaimed areas. The remaining trees were <br />planted by middle school students on Forest System property in the vicinity of the Dutch <br />Creek Diversion. Casual observation indicates that overall, about fifty percent of the <br />trees survived. The survival rate appears to be higher in shaded or sheltered areas <br />than in more exposed areas. Two hundred trees were planted on the lower third of the <br />Mine 1 Mine Bench Outslope. Of these two hundred trees, half were protected with tree <br />shelters, and the other half were planted unprotected. The overall survival rate of these <br />trees was also fifty percent. The survivors were almost evenly split between sheltered <br />and unsheltered trees. However, the trees protected by shelters appeared to be <br />healthier and more vigorous than the unprotected trees. <br />3 <br />