2018-11-19_PERMIT FILE - C2010089A (6)

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without treatment. Also, these impacts are for the time when the spoil material is leaching salts at a maximum. As described earlier, the TDS levels will drop over time as pyrite is oxidized and other salts are leached out of the spoil which will lessen the impact to the waters downstream over time. Six months prior to NHN Mine startup, monitoring of Spoil Spring #1, 001 discharge site, and SW -N3 (on Tuttle Draw) will be resumed if at that time it has been suspended. The approved "hydrologic monitoring plan" is described in Appendix 2.05.6(3)-3 at the end of this section. Impacts to receiving Waters - Meehan Draw Prior to mining disturbance in the drainage area of Meehan Draw, NHN will collect, for one year, four quarterly (baseline) water samples (for analyses as approved by DRMS) and four quarterly field parameters (flow rate, pH, conductivity, and temperature) from two additional Meehan Draw stream monitoring sites. These two sites are located approximately % mile downstream of the western border of the NHN Permit Boundary. These two sites are adjacent to the permit area and will help assess the impact of mining on the water quality of adjacent area. One of the sites is designated SW -N215 and is located on the unnamed draw just upstream from the confluence with Meehan Draw. The second site is designated SW -N216 and is located just downstream of the unnamed draw and the confluence with Meehan Draw. The locations of these new monitoring sites are shown on Map 2.04.5-1. For a year NHN will also collect samples at both SW -N215 and SW -N216 for four quarters following reclamation and prior to bond release. Additionally, NHN will collect water samples at two sites on the San Miguel River. Prior to disturbance in the Meehan Draw drainage and prior to reclamation bond release, NHN will collect, for a year, four quarterly water samples from SW -N217 which will be located just upstream of the confluence of Calamity Draw (at the bridge) and the San Miguel River and at SW -N218 which will be located just downstream of the confluence of Coal Canyon and the San Miguel River. These two new site locations are shown on Map 2.04.7-10. Surface water information collected at San Miguel River will be the minimum requirement under Rule 2.04.7-2. Instantaneous stream flow data from the USGS gauging stations located at the Brooks Bridge (USGS site 09174600) and at Uravan (USGS site #09177000) will be reported for the times of sample collection. The Brooks Bridge gauge is up stream if site SW -N217 and the Uravan gauge is downstream of SW - N218. 7) Effects Of Mining On The Local Geomorphology Impacts from mining on the local geomorphology will be long term, but appear to be of minimal significance. The reclaimed land will be graded to enhance irrigation and restore similar drainage patterns to those which existed on the area prior to mining. The increased runoff and consequent erosion potential on disturbed basins in the mining area due to the temporary loss of topsoil structure should be of minimal Section 2.05.6(3) Page 26 March 2018 (TR -16)