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P~~ e s <br />III. COMMENTS -COMPLIANCE <br />Below are comments on the inspection. The comments include discussion of observations made <br />during the inspection. Comments also describe any enforcement actions taken during the inspection <br />and the facts or evidence supporting the enforcement action. <br />outflow of the diversion above PM-8, east of the fence and directly through a portion of the <br />unfenced shrub study area. Significant rills are also forming west of the start of PM-8. A <br />representative slope of 29% was measured in the upper portion of PM-8, the design for this <br />channel indicates that the slope in the upper portion range from 15-22%. Erosion is occumng <br />above PM-8 and depositing sediment in the riprap portion at the start of PM-8. A portion of the <br />channel bank above the intersection with PM-8a is exposed without armoring and is eroding. <br />PM-8a is a meandering roughened spoil design. This channel is not stable with down cutting <br />through the spoil. There is a large gully south of PM-8a that begins as high up as the diversion <br />above the shrub study area. Upper PM-8b is a vegetated channel that drains into lower PM-8b. <br />Lower PM-8b is a roughened spoil meandering channel that was designed to drain into PM-8. <br />The instability and erosion at the lower end of the former East Wadge Pit and the final dozer pit <br />locations have been the focus of several previous inspections. In June 2004 the DRMS <br />recommended that SCC revise the drainage design for this azea by incorporating two additional <br />channels and also indicated in this report that the diversion ditch above the shrub <br />establishmenUelk fence be incorporated into the drainage design as a permanent post mine <br />feature (see inspection report issued 07/02/04). The drainage control was redesigned with TR-36 <br />including a meandering flow path design for Post-Mine Channels 8a and 8b and this was <br />subsequently approved in January 2005. Following this years spring runoff, SCC has done <br />substantial remediation grading and roughening above the junction of PM-8b upper and PM-8b <br />lower and has constructed a new diversion from the junction down to PM-8. An aerial photo <br />overview of this azea is shown in Photograph No. 7 which was taken on August 22, 2006 <br />following this inspection. Photographs of the gullies in the vicinity of the shrub plot and of the <br />PM-8, PM-8a, and PM-8b drainages are shown in Photograph Numbers 8 through 13. <br />Based on the observations made during this inspection it is appazent that the design is no longer <br />functional. The East Wadge Pit area beginning above the shrub plot study area all the way down <br />to the South Road will need to be reevaluated to provide stable slopes and effective post-mine <br />drainage control. One problem that has been noted in the past is that the temporary diversions <br />constructed to divert water away for the shrub plot have concentrated the flow of water elsewhere <br />resulting in significant gully formation. SCC will need to reevaluate the surface water runoff <br />control plan for the entire location described above. This azea will require reconstruction <br />grading. If major disturbance of the azea is caused by the regrading work, SCC should consider <br />reseeding the azea. SCC was notified during the Phase I bond release inspection that the East <br />Wadge Pit azea is not functional or stable, and therefore not eligible for Phase I bond release. <br />