_INSPECTION - C1994082 (7) - Laserfiche WebLink

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May 17,2011 C-1994-082/Yoast Mine SLB A major slide has occurred along Haul Road B. A network of scarps and cracks runs approximately 1,300 feet in length,and has affected an area approximately 300' wide. The slide appeared to be centered at the intersection of Haul Road B with the reclaimed haul road that extended around to Pond 012. The headscarp at this point is approximately 25' high. A slump has occurred in the shrub enclosure adjacent to YPM-22 (planted Fall 2010), and spring water was flowing out of the slump. The scarp is approximately 40' long with a 3' offset. Another slump developed on the north end of this same shrub enclosure,between YPM-22 and YPM-11,that is roughly 25' long and offset by 2'. There was a small slump at the inlet of Pond 014(new),but the slump above Pond 014,between YPM-14 and YPM-3 drainages had not changed. The slump at Pond 013 had expanded considerably. The scarp(200' long in April)on the slide was approximately 500' long, with a 25-30' height. The slide originated in reclaimed ground,cut through undisturbed ground to the north, and then cut back down into the reclaimed area. The toe of the slide extended southwest toward Pond 013, blocking the YPM-4 and YPM-4-1 drainages. The operator will need to clear these drainages as soon as conditions allow. Another small slump had occurred north of YPM-4, in an area where topsoil had been removed. There was considerable water flow from a seep from within the slide draining into Pond 013. The linear east/west crack noted in the April inspection, along the former highwall south of Pond 013 had opened more,and was approximately 12"wide. No vertical movement was observed along the crack. A crack was observed on the northern edge of the north pit,but closer observation was not possible since the road into the pit area was impassible. The observed areas of instability(Road B,Pond 013 drainage) are within areas that have undergone Phase I bond release. Since these areas will require extensive repairs and additional ground disturbance,the operator will need to submit a technical revision to the approved permit application that identifies the areas of disturbance(detailed map)and the proposed plan for repair and long term stability of these areas. Additional performance bond will be required to implement the approved revision. The Division believes these repairs are beyond normal maintenance and therefore,the repairs on these areas will reinitiate the backfilling/grading and stability requirements for Phase I bond release. These areas will be subject to the liability period of Rule 3.02.3 and the bond release criteria and schedule of Rule 3.03.1. Once Seneca and the Division have an opportunity to evaluate the entire mine site,we will determine what areas will be subject to the reinitiating of the liability period. SIGNS AND MARKERS—Rule 4.02: Mine identification and permit boundary markers were observed at the entrance to the site on County Road 27 and at each of the entrances to the ponds along County Road 37. Number of Partial Inspection this Fiscal Year: 9 Number of Complete Inspections this Fiscal Year: 3 Page 4 of 15