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Probable Effects on Surface Water Quality: Surface water runoff from the loadout azea passes through one of two sedimentation ponds. Discharges from these ponds are subject to effluent limits in the mine's NPDES permit. The existing ponds have performed adequately and no discharges in excess of NPDES effluent limits have been reported to date. Concentrations of total dissolved solids (TDS) are four times higher for water coming from the Rail Loop Pond than from the Truck Loop Pond, however, TDS concentrations coming from the ponds are generally less than ambient concentrations in Dry Creek upstream. Existing water quality in Dry Creek is unsuitable for irrigation and only marginally suitable for livestock. Most runoff from the rail loop, as well as the runoff from the three small area exemptions, is not treated; however, runoff from these sources do not appeaz to be affecting water quality. No adverse impacts from mining operations were projected in the HG Mine permit application and none have been observed to date. Probable Effects on Surface Water Quantity: Runoff from the loadout azea that is not diverted around the area of disturbance is retained in sedimentation ponds for a maximum of 36 hours. Water retained in these two sediment ponds result in some evaporative and seepage losses. The Dry Creek diversion downstream could potentially be impacted by loses of water due to storage in these sediment ponds. The acreage served by these two sediment ponds accounts for less than one- thousandth of the acreage drained by Dry Creek. Since the area to be affected is a fraction of the total watershed, the general watershed will not be significantly affected and runoff from the permit azea will continue to reach Dry Creek. All waters used for dust suppression, showers, and other operations at the loadout aze piped in from a well in the Yampa River alluvium (H-G Shallow Well No, 1), located two miles north of the loadout. HGTI owns the water rights for this well. HGTI owns an additiona190 acre-feet of water rights in the downstream Walker Ditch, which are not being utilized. These water rights can be used to compensate any downstream users for loss of water due to consumption at the loadout. HGTI has also entered into an agreement with the United States Fish and Wildlife Service (USFWS) to mitigate against losses of water to the Yampa River as a result of water consumption at the loadout. Please refer to Volume 2, Tab 21 of the permit application and Item XII of this document. 19