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1. A gully 2 to 4 feet deep extends approximately 120 feet downstream <br />from the toe of the steep riprap channel on the outslope of the large No. 1 <br />Mine bench. The toe of the riprap installation is being undercut, and it <br />appears that some riprap from the lower end of the channel has been <br />dislodged. The potential for further damage here appears to be fairly high; it <br />would appear that access for repairs can be achieved with a modest extent of <br />re- disturbance. <br />2. There are minor rills developing along the lower -most segment of the <br />reclaimed road bed. These appear to be associated with steep ephemeral <br />drainage chutes that originate on undisturbed slopes immediately west of the <br />lower road segment. This problem could be addressed by installing a few <br />water bars or dips to convey storm flow from the ephemeral drainage chutes <br />across the reclaimed roadway, rather than allowing it to run down the <br />roadway causing erosion. This lower road segment could be accessed and <br />repairs implemented without causing excessive re- disturbance. <br />3. On the upper No. 1 Mine Bench (the main bench area way up at the <br />end of the reclaimed access road bed), there is erosion along the vegetated <br />permanent channel, extending up the short portal backfill slopes at the upper <br />end of the bench. Unfortunately, when we did the reclamation project back <br />in the spring of 2000, the permanent channel on the relatively gently sloping <br />top of the bench was not riprapped, but rather was vegetated, and a series of <br />rock check structures was installed along the segment. A couple years after <br />construction, the upper two rock checks were blown out by a flow event, and <br />a gully developed which has deepened and migrated up slope in subsequent <br />years. <br />At present, a 50 foot segment of the channel in the vicinity of the portal <br />backfill slope is incised approximately 2 feet deep. The gully headcut <br />extends to within 20 feet of the backfill crest, which butts up against a <br />sandstone outcrop that was immediately over the portal entries. There is a <br />small hole at the point where the backfill meets the outcrop that appears to <br />be piping erosion. It is pretty clear that erosion of the backfill slope will <br />continue and worsen unless remedial /protective measures are implemented. <br />Unfortunately, to access the site with equipment will require tracking all the <br />way back up the extensively roughened and well vegetated road bed, <br />including a couple ephemeral drainage crossings. There would be <br />significant disturbance along the length of the roadbed, as well as on the <br />