_INSPECTION - C1982057 (40) - 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. General Comments This was an aerial inspection of the Seneca II-W Mine. The site was flown on the morning of 10/28/08, and Harry Ranney of the Division took 22 oblique and near vertical digital image photos. The images were viewed by Dan Mathews of the Division on 11/07/08. The images covered most portions of the mine disturbed areas. Site conditions appeared to be dry, although in a few locations there appeared to be a light dusting of snow or frost. Stock ponds T-20, T-18, T-5, T-26, T-27, and T-25 were observed; all except T-20 appeared to contain pooled water. Sediment Ponds 006, 016, 016A, and 017 were observed; all appeared to be full or nearly full, with no problems evident. Roads Road segments observed included most of the Ridgeline Access Road, Oil Well Access Road, the South Extension Light Use Road, fully reclaimed and reduced width sections of Road K, and portions of the reduced width sections of Road J. In general, the roads and reclaimed road segments appeared stable and well maintained. One exception is the slide damaged area along the Road J segment in the vicinity of Pond 016 and 016A, which appears largely as described in previous reports (refer to discussion under"Slides and Damage", below). Slides and Damage In a July 29, 2008 addendum to the 2008 Rill and Gully Repair Plan, the operator outlined a plan for geotechnical assessment and monitoring of the"Pond 016 Slide", along the segment of Road J adjacent to Pond 016, which was implemented in August(including installation of piezometers). In addition to the Pond 016 area slide along Road J (described above), there was renewed cracking and settling in spring 2008 immediatelyseXV the fenced shrub planting area up-slope from Pond 016. A evaluation plan to allow for assessment and development of remedial measures for the"shrub plot slide"was also included in the July 29, 2008 addendum. Although some grading to maintain the road through the"Pond 016 Slide"area has been performed, slide remediation is pending results of the geotechnical assessment. The extent of any grading in the vicinity of the "Shrub Plot Slide" could not be determined from the photos. The operator is asked to provide a written report by the end of 2008, addressing both the"Pond 016 Slide and the"Shrub Plot Slide". If a final report cannot be provided by 12/31/08, an interim report addressing the reasons for further extension,summary of results obtained to date, and a schedule for any further monitoring, as well as a deadline for submittal of a final report and implementation of the remedial plan should be submitted by that date. Hydrologic Balance Stock ponds T-25, T-26, and T-27 appear have been completed or largely completed during 2008. P.E. construction certifications will need to be provided for these ponds, and the ponds will need to be included in the quarterly pond inspection reports and future annual P.E. impoundment certification reports. One item of note is that it appears that T-25 embankment construction, topsoiling, and seeding has been completed, but the spillway outflow channel may not have been riprapped (although it is possible that riprap was obscured due to the photo angle). Permit Table 13-11A.3 specifies that the T-25 spillway outslope is to be lined with 12" D-50 riprap. Pond T-26 and T-27 specifications are for spillway outflow channel to be lined with 9" D-50 riprap. Photo angle and resolution did not allow for determination of riprap installation on the T-26 and T-27 spillway channels. Please ensure that the stock pond spillways are riprap lined in accordance with the approved plan. 3