_INSPECTION - C1994082 (71) - Laserfiche WebLink

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1 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. General Comments This was an aerial inspection of the Seneca II-W Mine. Harry Ranney of the Division took 27 oblique to near vertical digital aerial images during the fly-over of the mine site on May 20, 2010. The images were viewed by Dan Mathews of the Division on 6-01-10. The winter snowpack has largely melted off the reclamation, with only a few scattered snow patches at higher elevations on north and east facing slopes. Roads Only portions of the road network in the reclaimed mine pit areas were covered by the images; most of the length of the mine entrance road was not covered. No problems were apparent from the photos observed, but it is likely that typical spring road maintenance operations will be necessary. Hydrologic Balance Due to recent melt of the snowpack and subsequent precipitation, all sediment ponds covered by the photos contained full pools, as did Stock Pond ST-1. Sediment Ponds 10, 11A, 12, 12A, 13, and 14 were covered by the photos, and appeared to be stable and functional. Backfill and Grading/Slides and Damage The Pond 012 slide area appeared to be unchanged from recent inspections. TR-46(slide remediation plan) was recently approved by the Division. The plan includes grading to cut back the vertical scarp to competent material, installation of trench drains, and modification of the YPM 6-3 drainage along the toe of the slide. The remedial plan is to be implemented this field season. Ground conditions have not dried sufficiently to allow initiation of work at present. Reclamation of adjacent areas of the YPM 6-3 watershed, and the YPM 6-2 channel corridor will be performed in conjunction with the slide repair. A Lesser magnitude slide on a steep slope in the Pond 013 watershed was regraded and the slope reduced last fall. Based on the aerial images, it appeared that minor cracks may have recently developed along the crest of the repaired area, although no such cracks were evident during the April field inspection conducted by the Division. Ground check is warranted to determine if repair measures are warranted. An old settling crack along the reclaimed highwall to the west of Channel PM 1-1 (within and to the north of a large fenced shrub plot) is clearly visible in a couple of the photos, and it appears that further settling may have recently occurred. Ground check is warranted to determine if there has been additional settling, and if repair measures are warranted. Permanent channels and hillslope areas appear to have held up well in general, with few areas apparent from the aerial photos where erosion repair will be necessary(although it must be noted that the photos provide only partial coverage of the reclaimed areas). Certain locations of evident or apparent erosion are noted in photos attached to this report. The lower steep segment of TRM channel YPM-8, which has eroded in recent years, appeared to be in relatively good condition this year. An erosion control surge structure was constructed on the channel upstream of the problem segment, and it appears the structure functioned effectively. Revegetation With snowmelt largely completed, grasses on the reclaimed areas have recently initiated spring growth. Growth is more advanced and green-up more apparent on older reclaimed areas and south facing slopes. 3