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of this standard occurred at the Yoast monitoring points between 2013 and 2018. Both <br /> exceedances occurred at stream point YSG5. Although two of the discharges from Outfall 010 <br /> also had potentially dissolved selenium above the chronic table value standard,both these <br /> samples had total recoverable selenium that was less than < 1 ug/L indicating the elevated <br /> potentially dissolved selenium was related to lab error.None of the discharges from outfall 011 <br /> exceeded the Regulation 33 chronic selenium table value standard. This further suggests that the <br /> elevated concentrations observed in the watershed are unrelated to the runoff from the reclaimed <br /> mine. <br /> Spoil Springs <br /> Four spoil springs are actively monitored at the Yoast Mine. Spoil Spring 2 (YSSPG2), located <br /> above NPDES Outfall 011, is the only spring located within the Grassy Creek Watershed(see <br /> Map 1A and 1B). Analytical water quality data for YSSPG2 is provided in Table 16. The post- <br /> mining land use of the reclaimed parcels in the SL-7 bond release application are designated as <br /> livestock grazing and wildlife habitat. Therefore, the water quality data collected from these <br /> springs are compared to the agricultural use surface water standards as established in CWQCC <br /> Regulation 31. No exceedances of any of the agricultural use surface water quality standard <br /> occurred at YSSPG2 during the five-year monitoring period (2013 —2018). <br /> Sage Creek- Yampa River Segment 13e <br /> Total Recoverable Iron <br /> Total recoverable iron exceeded the Yampa Segment 13e water quality standard twice (n: 15) at <br /> YSS2 between 2014 and 2018 (Table 4).No exceedances of total recoverable iron standard <br /> occurred at YSSF3 during this time (Table 3). Both exceedances at YSS2 occurred in 2014. As <br /> previously described in the total recoverable iron section for Grassy Creek above, elevated total <br /> recoverable iron in the headwaters of these watersheds are often associated with increased <br /> concentrations of total suspended solids that occur in response to natural erosion from <br /> precipitation and snowmelt. A statistical comparison of the total suspended solids and total <br /> recoverable iron concentrations at YSSF3 and YSS2 indicate that they are strongly correlated <br /> (r2: 0.76 - 0.81) (see Figure 2). Total recoverable iron was monitored at upstream point YSSF3 <br /> and NPDES Outfalls 012, 013, and 014 during both sampling events with iron exceedances at <br /> SL-7 - 39 <br />