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Seneca 11 Mine <br />SL -6 Phase 111 Bond Release Request <br />June 2014 <br />to 400 feet below the Wadge Coal seam and approximately 60 to 100 feet below the Wolf Creek <br />Coal seam. <br />Instream Numeric Standards (CIQCC Regulation 33) <br />Seneca discharges surface runoff and spoil leachate into Segment 13b (Fish Creek and tributaries) <br />of the Yampa River, Colorado Water Quality Control Commission (CWQCC) Regulation 33. <br />The Seneca II Mine is required to monitor 17 of the parameters in that segment per its CDPS <br />and CDRMS permits, which is provided in Table 3, Attachment E. Table 4 (Attachment E) <br />provides a statistical summary of the water quality for the past three years (2011 to 2013) <br />measured at the mine's NPDES Outfall (designated NPDES8) and Stream Sites SSB12, SSF11 <br />and SSF13. Table 5 provides a comparison of those data with the Segment 13b standards. This <br />Paradox database generated table does not include the units of concentration (mg /l or ug /1) for <br />each parameter. The units used for each parameter are the same as those listed on the standards <br />table (Table 3) and are also the same as those used in the water quality statistical summary <br />reports. The frequency column on Table 5 (Attachment E) indicates, in this order: uncensored, <br />that is, the number of exceedances above the Method Detection Limit (MDL) /the number of <br />exceedances between the MDL and the Practical Quantitation Level (PQL) /censored, that is, the <br />number of sample values below the MDL but the MDL was higher than the standard /the total <br />number of samples. <br />Table 5 indicates that the total recoverable (IR) iron standard, 1.0 mg /1, was exceeded a total of <br />seven times (out of ten samples) at Fish Creek Sites SSF11 and SSF13. High TR iron values are <br />normally associated with high total suspended solids. No excursions of this standard occurred at <br />SSC10 (Cow Camp Creek, NPDES4 basin), SSB12 (Bond Creek, NPDES8 basin), or NPDES <br />discharges (NPDES8 at Seneca and NPDES4 at the PSCM). Therefore, these excursions on Fish <br />Creek are not caused by either mining operation. <br />The nitrite standard, 0.05 mg /1, was exceeded once at Site SSF13 with a value of 0.06 mg /1. Site <br />SSF13 exists on Fish Creek downstream of the confluences of Cow Camp and Bond Creeks. The <br />nitrite value at Site SSF11 (Fish Creek upstream of the confluences of Cow Camp and Bond <br />Creeks) from a sample collected on the same day (6/14/11) was 0.04 mg /1. No excursions of <br />27 <br />