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Surface Water <br />A summary of surface water sites is provided in Table 9. Stream monitoring <br />occurs on Sage Creek at Sites YSSF3 and YSS2, and on Grassy Creek at Sites <br />YSGFS and YSGS. These surface water sites are monitored biannually for <br />flow and field parameters (pH, temperature, and electrical conductivity <br />[EC]). All five NPDES sites are monitored monthly for NPDES parameters <br />and field parameters. Samples obtained at the stream sites are analyzed <br />for one of the new surface water parameter lists during spring runoff and <br />summer baseflow. Spring sites are monitored in the spring season. The <br />current surface water and spring monitoring program is presented in Table <br />15-9 of the Yoast Mine PAP. <br />All surface water data collected during this reporting period are provided <br />in Appendix D. Data for each site begin with a flow hydrograph of all <br />historic data (plus an annual hydrograph for NPDES sites), followed by a <br />listing of individual water quality and quantity data for the current <br />water year, followed by an instantaneous flow measurement report, and <br />followed by remarks, if present. This is followed by a TDS regression <br />plot using the LOWESS method (see the Ground Water Quality section). <br />A statistical report representing baseline (i.e., premining) data for <br />each site downstream of mining (when available) is provided in Appendix <br />D1 of the 2010 AHR. On this statistics report, "censored data" refers to <br />analytical values that were below the detection limit, which were censored <br />from the min/max/mean calculations. The time frame for baseline conditions <br />is listed under "conditions specified" at the bottom of each page. <br />Sage Creek <br />Site YSSF3. <br />This site exists on Sage Creek upstream of all potential Yoast Mine <br />discharges. It displays a decreasing TDS trend. <br />E <br />