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III. COMMENTS -COMPLIANCE Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. Hydrologic Balance (cont'd) Remedial measures will need to include dewatering of the sediment pond and removal of the sediment, and repair/maintenance of the primary discharge pipe as necessary. The operator was making preparations to initiate pumping as soon as possible. Discharge will be monitored and reported in conformance with CDPS permit requirements. Minor sediment cleanout at the inlet of the 36" road culvert will need to be completed as described under the previous section of this report. To the extent that sediment clean-out and storage can be completed in conformance with the approved plan within the storage cells on the non-toxic cover soil stockpile, the work can be undertaken with no additional permitting action required. If it is determined that the approved storage cells will not be adequate to accommodate the sediment volume, the Division will need to be contacted and an appropriate minor revision plan will likely be required. Please provide an estimate of the September 9 storm event magnitude within the context of the Technical Revision 19 (TR-19) that is currently under review, based on available documentation regarding the storm and on-site evidence on Munger Creek, as was previously provided for the July 25 storm event There was evidence of overland flow and minor rill erosion in the portal area. Diversions and sediment control measures functioned effectively. There was standing water in the SAE-1 sump area, and sediment had been deposited at the lower end of the sump, to within 18" of the top of the rock check structure. It was evident that there had been flow through the rock check, but it functioned well and remains intact. Minor maintenance is warranted to re-set silt fence installations below the rock check, in a couple locations, and sediment cleanout from in front of the rock check will be necessary when the area dries out. The temporary diversion ditch at the east end of the mine bench disturbance area functioned properly. The large boulder just above the point of diversion at the upstream end has not yet been removed from the channel. The boulder splits the flow coming down the channel, directing a portion of the flow directly toward the diversion berm. It is recommended that the rock be moved to the far left side of the channel, to direct flow toward the center of the channel. This will minimize the potential for a breach at the point of diversion, during future high flow events. Backfilling and Grading There was evidence of overland flow from upland areas on the interim reclamation fill on the mine bench area, and minor rill erosion, but no significant erosion, and no evidence of renewed cracking, caving, or sloughing. The area of the fill outslope subject to the surficial slump early this spring needs to be final graded le.g. clods broken up with a track hoe bucket or other appropriate means, cover soiled and seeded. The seedbed should be roughened to facilitate seed catchment and germination, and minimize erosion. Processinc Waste Drainage structures associated with the waste disposal area functioned well, with the exception of the sediment pond which was inundated by in-flow through the emergency spillway, previously described. Minor maintenance is warranted to remove sediment deposition in some locations along the upper diversion above the cover material stockpile.