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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. in disturbed area drainage being routed around the sediment pond and into Scullion Gulch without treatment. One of the eroded ditch segments ("Prep Plant Ditch") and the exposed pipe segment was observed on the morning of July 10. A second eroded ditch segment ("South Silo Ditch") was observed on a follow-up inspection of the location on the afternoon of July 11. The two ditches convey disturbed azea drainage from either side of the wash plant bench, down the steep benchoutslope and into Sediment Pond DP-l, within the D Portal facilities area. The eroded segment of each ditch is on the steep bench outslope segment. Permit Map 25 indicates that the ditches were rip-rapped at the time of initial constmction, although further design details could not be located. The ditches have been eroded for a number of years, but the gully segments remain steep sided with minimal vegetation establishment or other indications that the gullies are stabilizing. The eroded segment of the Prep Plant Ditch was estimated to be approximately 100 fee[ in length, withdowncutting averaging approximately 6 feet deep along the segment, assuming a 2 foot deep initial ditch. The South Silo ditch is routed across a rock outcrop along the upper segment ofhe outslope, with downcutting immediately down-gradient from the outcrop. An upper eroded segment averages approximately 3 feet of down-cut for approximately 15 feet, withdowncutting from 1 to 2 feet deep along the lower 30 to 40 foot segment. The exposed pipe segment referenced in the NOV is a black 6" diameter PVC pipe. The previously buried pipe had appazently been inadvertently cut and exposed by ditch maintenance activity within the Prep Plant Ditch, immediately adjacent to the Rotary Breaker Building on the Prep Plant Bench. BME surface operations foreman Rick Brady indicated that the pipe had been exposed at the ditch location several months previously, when he was asked about the pipe after it was observed on July 10. Mr. Brady was of the opinion that the original purpose of the pipe was to de-water afrench drain installed below the Rotary Breaker Building at the time of original bench construction. The pipe had previously swfaced a short distance down-gradient from the ditch, and extended along the slope to its outlet within thePond DP-1 emergency spillway outlet channel. This location was designated within the CDPS Discharge Permit as Discharge Site 004, the dischazge/sampling location for Wash Plant Processing Pond PP-2. PP-2 has not discharged for many years (water is recycled within the wash plant), and ScottWanstedt of BME was not certain whether the pipe had been connected to PP-2 outlet valve at the time it was exposed and severed, or whether the pipe had been modified at some point, so as not to be connected to PP-2. In any case, the pipe inlet at time of inspection was exposed within the Prep Plant Ditch, angled up such that the pipe opening was approximately 8 to 10 inches above the bottom of the ditch. High flows in the ditch could have resulted in dischazge of untreated disturbed flow through the pipe, bypassing the sediment pond. Inspection of the outlet azea revealed no indication that there had been any discharge through the pipe. Mr. Wanstedt indicated that he had not been awaze of the exposed pipe inlet until it was observed on the inspection. Mr. Brady's comments indicated that he appazently had been previously awaze that the pipe had been exposed. The pipe problem was abated by cutting off the exposed segment of the pipe, capping it and burying the capped end of the pipe within the ditch embankment, prior to lpm, on 7/10/02. The remaining abatement item for this NOV relates to the eroded ditch segments, and requires that the operator install riprap as necessary to stabilize the eroded ditch segments by August 1, 2002.