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Peak flows for the surface water sites at Trapper Mine in 2017 were similar to the higher <br />flows in 2016. The precipitation in 2017 was 18.86 inches, or above the 40 -year average for the <br />Trapper Project of 16.6 inches. The previous seven years of annual precipitation to 2005 had been <br />below normal precipitation prior to the larger precipitation in 2005 through 2011, then the very low <br />precipitation in 2012, the near normal in 2013, the slightly above normal precipitation in 2014 and <br />2015, slightly below normal in 2016 and the above normal in 2017. No failures or monitoring site <br />problems were encountered during 2017 and no compliance limits were exceeded in 2017. <br />Values of total suspended solids (TSS) were generally on the low side of ranges observed in <br />previous years. Total dissolved solids (TDS) were generally in an indirect relationship with flow <br />rate when adequate flow occurred at a site to determine the relationship. The TDS of the surface <br />water from the mine area is similar to the TDS from the non -mined area and, therefore, an increase <br />has not been defined, except for an increase in TDS during low flow conditions at NPDES sites 001 <br />and 011. The TDS, conductivity and major constituents varied over expected ranges with an <br />increase in values as ground -water flow to the stream becomes a larger portion of the total flow. The <br />SAR values measured in 2017 were within the natural ranges for this site. Other chemical <br />constituents analyzed from samples collected from the surface water sites showed little change. The <br />variations and magnitude in iron concentration observed in 2017 were typical of natural values for <br />these sites. The total aluminum concentrations observed in 2017 were similar to concentrations <br />observed in previous years. The remainder of the minor constituents measured in 2017 were low <br />and within natural ranges. Monitoring data indicates that Trapper Mine sediment control structures <br />prevented any significant impacts on the surface water systems downgradient of the mine in 2017. <br />Trapper Mining Company 6-6 <br />2017 Annual Report <br />