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September 15,2020 C-1981-025/North Thompson Creek Mine RDZ <br /> The following ponds were inspected: the Long Pond,Treatment Pond T-1, Treatment Pond T-2,the Polishing <br /> Pond(Pond P-9), and the Refuse Pond. All but the Refuse Pond were discharging. At the upper end of the <br /> treatment system, orange precipitate was visible,indicating iron in the water. The water discharging from Pond 9 <br /> was relatively clear,with no mineral staining or odor. The flow through the ponds appeared to be approximately <br /> the same at the upper end(pipe from mine above the Long Pond) and out of Pond 9. The flow also appeared to be <br /> similar to the flow during previous inspections. No problems were identified with the ponds, although the amount <br /> of biomass in some of the ponds is significant, and this material may need to be removed in the next couple years <br /> to assure proper functioning of the pond treatment system. <br /> No problems were identified with most channels between the ponds or the aeration ditch above the Long Pond. <br /> (An exception is described below.)At the outlet to Pond P-9, the diversion of discharge to the Refuse Pond <br /> (performed as a result of a violation in 2014)is functioning well, and there was no discharge to the creek(Outfall <br /> 01). The old channel out of Pond T-2(with a pipe spillway)was dry; discharge from Pond T-2 flows directly to <br /> Pond P-9. <br /> The ditch into the Refuse Pond(from Pond 9)was not functioning. Water was flowing over a breach in the berm <br /> and into the wooded area adjacent to the mine site. This was approximately 100 feet west of the Refuse Pond. The <br /> source of the problem appeared to be a buildup of sediment and vegetation in the channel. The water was <br /> infiltrating before reaching North Thompson Creek. Rob Zuber notified Jim Stover of this problem after the <br /> inspection on September 15. Rob returned to the site on September 17, and the problem was fixed. Sediment and <br /> vegetation had been removed from the ditch,the berm had been built-up, and water was flowing to the Refuse <br /> Pond. However, this channel has other reaches where this same issue could happen in the future. It is <br /> recommended that this ditch be cleared of sediment and/or vegetation to prevent more breaches. <br /> SIGNS AND MARKERS—Rule 4.02: <br /> Stream buffer signs were seen between the ponds and North Thompson Creek. Entrance signs were in place. <br /> DOCUMENTS RECEIVED-none <br /> OTHER(SPECIFY)—none <br /> ENFORCEMENT ACTIONS/COMPLIANCE <br /> No enforcement actions were initiated as a result of this inspection,nor are any pending. <br /> Number of Partial Inspection this Fiscal Year: 0 <br /> Number of Complete Inspections this Fiscal Year: I <br /> Page 3 of 7 <br />