2013-10-07_REVISION - C1981025 (8)

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ponds have been reclaimed. Thus any such impacts to these alluvium materials are likely to diminish with time. The water used at the loadout site was pumped from wells completed in the Roaring Fork alluvium. The withdrawal of this ground water was small and was covered under a plan of augmentation that minimized impact to the quantity of alluvial ground water. All such withdrawals were suspended with reclamation of the site. Alluvial groundwater regimes have likely been reestablished in these highly permeable materials. Flood irrigation has been reestablished on the alluvial valley floor. There has been no evidence of any adverse impacts to the ground water quality at the loadout site. 2) Surface Water The determination has been made that there is no impact to Middle Thompson Creek. Surface disturbances in the Middle Thompson Creek drainage included two flow monitoring flumes, a portal, an air shaft, and roads. The roads have been stabilized, and have been permitted for retention. All of the other disturbances were small, and have been reclaimed. There has been no mine water discharged to Middle Thompson Creek. Except for flow measurements, there has been no monitoring of surface waters in the Middle Thompson Creek drainage. The determination has been made that there is no impact to the Roaring Fork River from disturbances at the loadout site. The loadout site has been reclaimed. Surface water inflows to North Thompson Creek within the permit area include the discharges from the portals of both Mine No. 1 and Mine No. 3, surface water runoff 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. C0-0029599 (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. (a) Runoff from Disturbed Areas 16