2014-05-12_PERMIT FILE - C2010089 (3)

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the quality and quantity of the water in Coal Canyon. The two sites are referred to as South Coal Canyon (SCC) and North Coal Canyon (NCC). These two sites are shown on Map 2.04.5 -1. SCC is located about half a mile north of the confluence with the San Miguel River and NCC is located where Z26 Road crossed Coal Canyon. These two sites were monitored on 3/11/2011 and the results (sample analyses and physical properties) have been added to Appendix 2.04.7 -2 of this application. The results show that NCC had a flow of 0.06 ft /sec (about 27 gpm) and a TDS (calculated) of 2640 mg /1. At SCC, the flow was 1.296 ft /sec (about 582 gpm) and the TDS (calculated) was 2940 mg /1. The New Horizon 1 Permit contains historic flow and water quality data that was collected from four additional sites in the immediate permit area. Two of these sites on Nygren Draw, SW -N6 and SW -N7 monitor Nygren Draw. Two sites in Tuttle, one upstream of NH 1 Mine and one downstream from the old Peabody Mine, provide information for Tuttle Draw. The two sites were monitored during 1986 and 1987 following the cessation of mining but prior to NH 1 reclamation, (see Map 2.04.7 -1 for location). Data is also available for 2 sites in Tuttle Draw, SW -N1 and SW -N3, (see Maps 2.04.5 -1 and 2.04.7 -1, respectively, for locations). These two sites are currently included in the New Horizon 2 Hydrological Monitoring Program and this data is presented as baseline data for New Horizon North. The monitoring data for these 4 sites is included in Appendix 2.04.7 -2 of this application. SW -N213 and SW -N214 (formerly SW -N6 and SW -N7) on Nygren Draw resumed monitoring in 2011. Surface Water Flow The average annual precipitation in the NHN permit area (Uravan Site, 1960 -2009) is 12.5 inches per year (see Section 2.04.8 of this permit application). The permit area is semi -arid. Surface flow at NHN is dependent on irrigation water from the 2nd Park Lateral ditch system. Map 2.04.7 -1 shows the location of the surface water monitoring sites and the location of the 2 Park Lateral. Monthly monitoring of the surface water flow began on October 17, 2008 when flows occurred at the nine new surface water monitoring stations and will continue on that schedule for the foreseeable future. The irrigation season (ditch flowing) during this current period of monitoring ended on 10/5/2008, began again on 4/23/09 and ended on 10/5/09. Two ditch runs (6 days to 8 days) were conducted (one in November and one in March) during the off season to fill cisterns and stock - ponds. The Colorado Cooperative Company records show that during 2009 that 19.20 cfs was delivered to the lower end of the ditch. About 10.5 cfs of the total flow was diverted above the NHN permit area leaving about 8.7 cfs to flow into the NHN permit area in the lower 2 Park Lateral. The flow data and hydrographs of flow from the 17 (16 remaining after SW -N206 was destroyed) new surface water monitoring sites are contained in Appendix 2.04.7 -2. The results of the new monitoring are summarized in Table 2.04.7 -5 which also includes data from monitoring at the old Nucla Mine. The data in this table indicate that the average annual mean surface water flow onto the NHN permit area is on the order of about 3,949 acre -feet (ac -ft) and the flow out of the NHN area is about 2,742 ac -ft per year. The difference is about 1207 ac -ft per year. Some of this difference is the result of evapotranspiration which as discussed previously is on the order of 2.1 ac -ft per acre per year. The permit area including the haulage corridor is about 320 acres. Evapotranspiration could account for about 672 ac -ft per year. Therefore, about 535 ac -ft is still not accounted for. Flow in Nygren Draw and seepage from the toe of the old mine backfill accounts for an additional 243 ac -ft. The remaining 292 ac -ft either leaves the permit area as higher than estimated evapotranspiration or infiltrates into the bedrock zones. The baseline Section 2.04.7 Page 18 January 2012