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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. 02242 02245 - A couple hillslope gullies extend into the permanent channel along reach upstream of the oil well road culvert, and have contributed to erosion within the channel. 02246 02247 02248 -Steep channel segment (21 % grade) below oil well road culvert (lower segment of JJ-BB). Riprap size appears marginal; scour evident with liner exposed in some locations. Convex channel cross-section (high in middle) with erosion along edges of riprap. 02249 -Non-riprapped segment at base of steep reach downstream from Oil well road culvert. Eroded upper segment and silted in lower segment. Channel needs to be shaped to conform with design, riprap extended through eroded segment, and vegetated segment reseeded. A short riprapped segment immediately upstream from the Haul Road "A" culvert inlet appears stable with adequate capacity. Drainage Channel Summary Maintenance is necessary in a number of locations along the inspected channels, where riprap has been washed out, or where flow has scoured along the edge of the riprap. Channel shape (wide and shallow, or convex) with inadequate armoring of channel sides appears to have contributed to erosion within the channels in a number of segments, and regrading to establish design configuration wilh properly armored sideslopes is warranted. Other concerns include channel scour associated with erosion from hillslope gullies in a couple locations, possibly undersized riprap in at least one steep channel segment, and apparent piping erosion under the rock check structures in the upper 005 Gulch. Operator needs to perform maintenance including regrading, riprap installation, and revegetation as necessary to stabilize the channels and comply with approved design specifications. , Roads The Road "G" reclamation project to reduce the road to post-mine conditions was in progress and dirt-work was nearing completion. The road shoulders and slopes will be seeded this fall. The project appears to be on schedule. The Ridgeline post-mine access road is largely completed. Remaining work appears to be limited to seeding of cuts and fills in some locations and gravel surfacing of a few segments. This project appears to be on schedule. Drainage maintenance work is necessary in a few locations, due to recent storm runoff. Specifically, it was noted that Culvert PM-4 at the crossing of the 005 Gulch channel was partially obstructed and needs clean-out. Also, there was erosion observed at a road ditch outlet location further to the east. Grading and riprap installation is warranted. Maintenance was noted to be necessary on at least two locations along the Mine Entrance Haul Road. Specifically, storm runoff had largely silted in the stock tank/sediment trap T-1, upstream from the inlet to culvert ME-2. In addition, a significant quantity of road gravel had been deposited at the outlet of Culvert ME-5. This culvert is at the lower end of Ditch HRD-A2-ME-5. T-1 Sediment Trap needs to be cleaned out, gravel accumulation at ME-5 outlet needs to be removed and the disturbed area seeded. There appears to have been a silt fence installed in the vicinity of the ME-5 outlet at one time (as indicated on the Exhibit 13-12.2 "As- Built"). Concentrated flow from the culvert in this location may not be compatible with a typical silt fence installation, however measures to minimize sedimentation to the adjacent ephemeral drainage appear to be warranted. Silt fence with a rock check protective barrier or an appropriate alternative measure to minimize sedimentation needs to be installed. The oil well road ditch down-drain to the OW-1 culvert inlet has eroded and needs to be riprapped