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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. DMG Inspection Observations of July 20~h Storm Event Effects RSRDA Borrow Area and Light Use Road Inspection began on the morning of July 26 at the RSRDA Borrow Area. The reclaimed soil borrow area is located to the east and up-gradient of the RSRDA Refuse Disposal Area. Drainage from this area flows through a short, steep canyon down to the RSRDA upper diversion. Reclaimed drainage channels in the borrow area all showed evidence (water marks and organic debris deposition) of recent flows bankfull or higher. Upland slopes showed evidence of overland flow, with some areas of concentrated shallow rills. In several locations, steep riprapped segments of the permanent channels were damaged and repairs will be necessary. Maintenance may also be warranted in various flatter channel segments to remove sediment deposition and restore design dimension. Photos 2636 and 2637 show the northern channel; repairs are necessary at lower end of riprap segment, and cleanout along lower flat segment of the channel may be warranted to restore design dimension. Photo 2639 shows the upper segment of the middle reclaimed channel, where riprap cobble was scoured out and repair will be necessary. Photo 2640 shows debris and sediment deposition along the lower segment of the middle channel. Photo 2643 shows the terminal berm/sediment trap at the lower end of the light use road up-gradient of the borrow area. There appeared to have been some piping erosion through the berm at this location, which will need fo be repaired. Water bars along the light use road segment up-gradient to the southeast appear to have functioned well. Photo 2646 is a view down the south permanent channel, showing riprap scoured out and liner exposed along the lower portion of the riprapped segment. Photo 2648 shows the segment of light use road leading from the soil borrow area down to the RSRDA refuse area. There is a series of water bars along this road segment that appeared to have functioned properly, although maintenance will be required due to sediment accumulation. A significant gully formed down the road outslope (visible in Photo 2648) below the outlet of the 3rd water bar from the top. The gully will need to be repaired, and the outlet channel down to the creek will need to be stabilized by rock, or protected by appropriately sized flexible pipe or suitable alternative. RSRDA Refuse Disposal Area Photos 2650 and 2651 show track-hoe repairing low gradient segment of refuse area upper diversion, just downstream along the ditch from the junction of the canyon drainage, which conveyed flows from the borrow area and undisturbed lands in the watershed. There was minor siltation in the upper diversion extending a short distance up-gradient from the junction (due to water backing up from the confluence), but most of the length of the upper diversion up-gradient of the confluence was unaffected by the storm. Below the confluence, low gradient segments of the ditch were silted in, and steep segments along the "B"segment of ditch on the south perimeter of the refuse area were heavily eroded. The ditch had breached along the "B" segment, but interim remedial repairs had been made prior to the inspection to restore the ditch capacity. Erosion repairs and riprap installation had not yet been implemented along the "B" segment. Sediment had been excavated along the upper low gradient "A" segment, and riprap installation was in progress. The ditch had effectively diverted upland flow around the perimeter of the refuse area, but failure along the steep south perimeter resulted in ditch erosion into refuse material beneath the riprap, and breaches along the west perimeter resulted conveyance of sediment, rock, and refuse material off-site. 4