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All five NPDES sites are monitored monthly for NPDES parameters and <br />field parameters. Samples obtained at these stream and NPDES sites are <br />analyzed for the surface water parameter list, Table 8, during April, <br />May or June, and September. Spring sites are monitored in the spring and <br />fall seasons. The current surface water and spring monitoring program is <br />presented in Table 15-9 of the Yoast Mine PAP. <br />A11 surface water data collected during this reporting period are <br />provided in Appendix D. Data for each site begins with a flow hydrograph <br />of all historic data (plus an annual hydrograph for NPDES sites), <br />followed by a listing of individual water quality and quantity data for <br />the current water year, followed by remarks if present. This is followed <br />by a TDS regression plot using the LOWESS method (see the Ground Water <br />Quality section), and a listing of historic percent milliequivalent <br />values for major ions and TDS values. A statistical report representing <br />baseline (i.e., premining) data for each site downstream of mining (when <br />available) is provided in Appendix D1. On this statistics report, <br />• ^censored data" refers to analytical values that were below the <br />detection limit, which were censored from the min/max/mean calculations. <br />The time frame for baseline conditions is listed under "conditions <br />specified" at the bottom of each page. <br />Sage Creek <br />- Site YSSF3. This site exists on Sage Creek upstream of all potential <br />Yoast Mine discharges. This year, no flow was observed in September. It <br />displays a decreasing TDS trend. <br />- NPDESI2. Mining in this basin began in 2000. Reconstruction of the <br />water augmentation Pond Y1 (Site YSSF2) was completed on September 13, <br />1999. It is now referred to as Pond 012 (NPDESI2). This pond began to <br />flow again (after reconstruction) in April 2000. The average flow value <br />for this year is 0.028 cfs, which is 45$ of the historic (2000-2005) <br />average for Pond 012, 0.062 cfs, but only 22~ of Pond Yl's historic <br />(1991-1999) flow value, 0.129 cfs. The low flow average this year may <br />have been a result of surface water runoff being intercepted by an <br />10 <br />