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III. COMMENTS -COMPLIANCE <br />Below aze comments on the inspection. The comments include discussion of observations made during the <br />inspection. Comments also describe any enforcement actions taken during the inspection and the facts or <br />evidence supporting the enforcement action. <br />Post-Mine Channel Bottom Width Grade <br />PM-13 u er I 1 feet 29% <br />PM-13 mid 14 feet 26% <br />PM-13 lower 21 feet 28% <br />Avera a ri ra size ~ 6-9 inches <br />PM-10 u r 13 feet 25% <br />PM-10 mid 14 feet 22% <br />PM-10 lower IS feet 18% <br />Avera e ri ra size ~ 12-15 inches <br />PM-9 u er 13 feet 14% <br />PM-9 mid 11 feet 22% <br />PM-9 lower 13 feet 21% <br />Avera e ri ra size _ 7-9 inches <br />Based on the field measurements taken and comparison with design criteria, it was <br />determined that all channels met minimum design specifications except for two locations <br />as described below. All of the channels were overbuilt with regard to size (bottom width <br />and side slopes), and riprap specifications. Channel slopes measured with an <br />inclinometer were all generally consistent with design slope information. The location <br />and density of the reconstructed drainages aze consistent with the pre-mining tributary <br />drainage system. Post-mine drainages PM-9 and PM-10 were constructed at the <br />approximate location ofpre-mining intermittent streams. Additional drainage density <br />was added with PM-13. <br />The entire tributary drainage system within the reclaimed North Pit has been <br />reconstructed and is functional with exception of two locations that will require <br />additional work or repair. These locations include upper to mid PM-13 and upper PM-10 <br />and these portions of these channels will be excluded from the Phase I bond release as <br />described below. <br />At the head of PM-13 erosion is occurring in the form of rills above the start of the <br />channel. Photo No. 3 shows the rills at the head of PM-13. The uppermost portion of <br />PM-13 is void of riprap and erosionally unstable. There is a gully down the center of the <br />channel and fabric is showing through in several areas of the upper channel. At about the <br />mid section of the channel significant bank erosion on the east side is occumng. <br />Photographs of the upper and mid sections of PM-13 are shown in Photograph Numbers <br />4 and 5. Erosion has been repaired above Pond 11A by use of hummocks to slow down <br />runoff. The runoff flows through the roughened azea directly into PM-13 on the <br />southeast side. A gully has eroded through the hummocky area and will likely impact the <br />