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runoff from these sources passes through a vegetative filter and does not <br />appear to affect water quality. No adverse impacts from mining operations <br />were projected in the HGT permit application and none have been observed <br />to date. <br />Runoff from the Loadout area that is not diverted around the area of <br />disturbance is retained in sedimentation ponds for a maximum of 36 hours. <br />Water retained in the two sedimentation ponds experiences some losses <br />through evaporation and seepage. The Dry Creek diversion downstream <br />could potentially be impacted by loses of water due to storage in the sediment <br />ponds. <br />The acreage served by the two sediment ponds accounts for less than one - <br />thousandth of the acreage drained by Dry Creek. Since the area to be <br />affected is a fraction of the total watershed, the watershed will not be <br />significantly affected and runoff from the permit area will continue to reach <br />Dry Creek. <br />All waters utilized for dust suppression, showers, and other operations at the <br />Loadout were piped in from a well in the Yampa River alluvium (H -G <br />Shallow Well No. 1), located two miles north of the Loadout. H -G Shallow <br />Well No. 1 was sealed in 2011. HGT owns an additional 90 acre -feet of <br />water rights in the downstream Walker Ditch, which are not currently being <br />utilized. Facilities have been dismantled in 2011, and the remaining office <br />trailers were in the process of being removed from the site in 2013. <br />Plumbing to the trailer was dismantled during the removal of the office <br />trailers. <br />These water rights can be utilized to compensate any downstream users for <br />loss of water due to consumption at the Loadout. In addition, HGT has an <br />agreement with the United States Fish and Wildlife Service (USFWS) to <br />mitigate against losses of water to the Yampa River as a result of water <br />consumption at the Loadout. Please refer to Volume 3, Tab 21 of the permit <br />application and Item XII of this document. <br />2. Ground Water Impacts <br />The Lewis shale has low conductivity values and is generally considered to <br />be an aquitard that retards transmission of surface water to the Twentymile <br />Sandstone, the underlying regional aquifer. This low conductivity unit <br />results in low well yields that preclude the use of waters from the Lewis shale <br />for other than stock watering (See Seneca II -W Permit, C- 1982 -057, Tab 7). <br />Water samples from the two existing alluvial wells at the Loadout, which are <br />completed in part in the underlying Lewis shale, often exceed water quality <br />standards for stock watering. Operations at the Loadout should not impact <br />this ground water. <br />Hayden Gulch 26 February 11, 2014 <br />