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The reference to `Footnote 5' (rather than Footnote 4) above is either a <br />typo, or a result of a deleted footnote in a later revision. In any <br />case, Outfall 006 has NOT exceeded 4.6 ug /l for selenium (in any form) <br />in the past SIX years. It is unknown as to why this exceedance occurred, <br />although we suspect it may be due to the record snowfall and rainfall, <br />and near - record snowmelt runoff that occurred in Routt County in winter <br />and spring of 2011. Perhaps that unusually high runoff somehow mobilized <br />the selenium. This excursion was transitory; selenium values since then <br />(as of June 2012) have been below the standard. <br />For NPDESI7, the four excursions of the selenium stream standard noted <br />above sk were not NPDES permit limit excursions. The permit limit for <br />this outfall for selenium is to "Report" only. This outfall has a NPDES <br />Compliance Schedule to meet the selenium limit by December 31, 2015. SCC <br />is currently investigating means of selenium control. SCC is also <br />performing an aquatic life survey in this drainage, and is also <br />investigating the possibility of a site - specific standard. <br />Surface Water Summary. Flow values from all NPDES ponds were above <br />average this year due to near record snowpack runoff. TDS values at <br />NPDES Ponds 005 and 006 are increasing, as are TDS values at downstream <br />surface water Sites WSHF1, WSD5, WSSF3 and all Spoil Springs except 45. <br />The TDS trend is decreasing at NPDES Ponds 009 and 015, and Spoil Spring <br />5. The TDS trend is stable at NPDES Ponds 016 and 017. NPDES discharges <br />are normally suitable for livestock and irrigation, but sometimes exceed <br />water quality standards for aquatic life. <br />In the Probable Hydrological Consequences (PHC, Tab 17, Table 17 -42b) <br />section of the Seneca II -W Mine PAP, predictions were made as to the <br />expected TDS increases to be observed at various surface water sites. <br />The following table outlines these predictions along with this year's <br />observed average values (irrigation season, June - September). <br />Site Predicted TDS values (mg /1) <br />WSHF1 2527 <br />WSD5 2451 <br />23 <br />This yearrs average TDS (m /1) <br />1970 <br />1640 <br />