_INSPECTION - C1994082 (66) - Laserfiche WebLink

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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. Roads The primary permanent access road (former Haul Roads"A"and "B") had only recently melted off, but the travel surface was generally well maintained. Beyond the upper end of Road "B", Light Use Road 3A travel surface became increasingly soft. Due to muddy conditions we did not attempt to travel further south than the fenced shrub plot adjacent to LU-3A. Drainage maintenance work will be warranted at various locations along the mine entrance access roads and LU-3A, to repair minor erosion and re-set, replace, or install additional straw wattles, TRM liner material, and rock checks, as soon as ground conditions allow. Minor road outlet erosion was observed in various locations along the roads, and downcutting was noted along the segment of LU-3A adjacent to the fenced shrub plot. One significant gully, which resulted in sediment deposition outside the permit boundary along the Scotchman's Gulch channel near Culvert Installation YA-6 was observed, and NOV CV- 2009-002 (described above)was issued as a result. Hydrologic Balance Snowmelt at the site had recently begun in earnest, and permanent channels in the accessible watersheds were flowing. Interior portions of the reclaimed mine site still contained significant snow cover on north and east facing slopes, and roads were too muddy to access upper portions of the reclaimed watersheds. Permanent Channels Upper watershed channels could not be accessed. Lower watershed channels that could be accessed were carrying significant turbid flow. Segments of Channels YPM 6-2 and 5-1, upstream of Pond 12A were observed rather closely. These channels were carrying heavy flow; but it appeared that maintenance grading and TRM liner or riprap replacement would be warranted in some locations, where flow had escaped to the outside of the liner and resulted in side scour. Sediment Ponds Sediment Ponds 10, 11, 12, 12A, 13, and 14 were accessible and were inspected. All of the ponds contained open water and all were discharging. Pond 10 was inspected in the morning and was discharging clear flow; discharge was through weep hole, as water level was several inches below top of riser. Remaining ponds were inspected in the afternoon, and all of the ponds were discharging significant flow. Ponds 12 and 12A form a two pond system, with the compliance point under the CDPS discharge permit being the outflow from Pond 12. Discharge from Pond 12 was somewhat turbid, and a sample was obtained and split with the operator. There was heavy runoff of highly turbid snowmelt runoff into Pond 12 at the time the sample was obtained. Settleable Solids was analyzed by Grand Junction Laboratories on 4/24/09, and the reported value was 0.3 ml/I, which is below the CDPS permit standard of 0.5 ml/I. Inflow was discharging through the weep hole on the spillway riser at the time of the sample, with water level within one inch of the top of the riser. Pond 12A was discharging turbid flow, but because the pond is in series with Pond 12 and is not a CDPS discharge point, the discharge was not sampled. It was noted that a spoil spring has developed and was discharging clear flow of approximately 20 gpm from a point very near the downstream toe of Pond 12A. The operator will need to initiate monitoring of this spring and be watchful for impacts of the spring on stability of the Pond 12A embankment(apparent affect on stability to be noted in quarterly pond reports and annual impoundment certifications). At the time of the inspection, no cracks, slumps, or other indications of embankment instability were evident. 4