2009-05-12_GENERAL DOCUMENTS - C1981025

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from reclaimed disturbed areas, discharge from Mine No. 2, flows from springs and seeps, runoff from undisturbed areas of the permit, and areas of watersheds above the permit boundary. Discharges into North Thompson Creek from the mine portals of Mine No. 1 and Mine No. 3, and runoff from disturbed areas of the permit, were subject to the CDPHE Permit No. CO-0029599 (CDPS). This permit placed some limitations, and requires periodic monitoring, for the following parameters: flow, oil and grease, pH, total suspended solids, total dissolved solids, whole effluent toxicity, potentially dissolved cadmium, potentially dissolved iron, and total recoverable iron. One-time analyses were required upon renewal of the CDPS permit for copper, lead, mercury, nickel, selenium and silver. Monitoring of the discharges is not required for parameters that are not identified by the CDPHE as being of concern. Of the water quality standards that were established for North Thompson Creek, there was no testing for dissolved oxygen, fecal coliforms, F. Coli, chlorine, nitrite, asbestos, antimony, beryllium, thallium, and uranium. There was no baseline monitoring for silver. On or around April 20, 2006, The CDPHE Water Quality Control Division (WQCD) terminated the Colorado Discharge Permit No. CO-0029599. WQCD subsequently wrote a letter to MINREC stating that the CDPS permit should not have been terminated and requested that MINREC submit an application for a new CDPS permit. MINREC has submitted an application for a new CDPS Permit. The permit is still under review by WQCD. The reason WQCD requested new permit at the North Thompson Creek Mine is because of the passive water treatment system treating the No. 1 Mine and No. 3 Mine Portal discharges. WQCD requires a discharge permit on all water treatment systems. The issue of concern is that the discharge from the No. 3 Mine Portal has an iron concentration that exceeds the receiving stream standard. However, after the No. 1 Mine and the No. 3 Mine discharges mix and flow through the passive treatment system, the majority of the iron is removed and the resulting discharge is in compliance with receiving stream standards. (a) Runoff from Disturbed Areas Disturbed surface areas from mining operations have been reclaimed. The operator demonstrated in Bond Release SL-04 that contributions of suspended solids from these reclaimed areas are not greater that contributions from adjacent undisturbed areas. There has been no recorded overland surface flow from reclaimed disturbed areas of the permit to North Thompson Creek. All former sediment control structures have been reclaimed, or permitted for retention for other purposes. Reclamation activities associated with the removal of the four water monitoring flume bases are being managed by small area exemption procedures. The determination was thus made in Bond Releases SL-04 and SL-05 that there is no adverse impact to surface waters by surface runoff from the mine site. (b) Flows from Mine Portals North Thompson Creek C-1981-025 Permit Renewal 05 12 May 2009 20