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monitoring requirement was discontinued in 1993 (although field , <br />parameters were occasionally collected in 1994 to 1997). A statistical <br />summary of baseline chemistry data is provided in Appendix D1. Its TDS <br />plot indicates a slightly increasing trend. <br />Grassy Creek / Annand Draw <br />- NPDES10. This sediment pond on Annand Draw was completed in August <br />1996. Flow was observed at this site for the first time ever on February <br />24, 1997. Flow at this pond is continuous. Average flow this year was <br />0.227 cfs, which is 39% above its historic (1997-2008) average, 0.163 <br />cfs. This pond was dredged out in 2002. Baseline data for this site, <br />both downstream (Site YSA4) and upstream (Site YSAF4) of the pond, have <br />been provided in Appendix D1. NPDES10 exhibits a recently stable TDS <br />trend (SF=0.5), peaking in 2002. <br />- NPDESII. This pond exists on a Grassy Creek tributary and was <br />completed in October 1997. Flow was first observed at this site in 1998. <br />No discharge occurred in 1999 or 2000. This year, this pond started <br />flowing in April and stopped flowing in July. This year's average flow, <br />0.095 cfs, is over three times its historic (1998-2008) average, 0.025 <br />cfs. Due to high sediment level, this pond was dredged out in the fall <br />of 2003. TDS values exhibit an increasing trend. <br />- Site YSGF5. This site exists on Grassy Creek below the NPDESII pond. <br />A statistical summary of baseline chemistry data is provided in Appendix <br />D1. Its TDS plot indicates a recently decreasing trend (SF = 0.5), with <br />the peak value occurring in 2002. <br />- Site YSG5. This site exists on Grassy Creek below all discharges from <br />both the Yoast and Seneca II Mines. It became part of the required <br />monitoring program in October 1995. TDS values here are affected more by <br />the Seneca II Mine than the Yoast Mine. TDS values exhibit a decreasing <br />trend (SF 0.5). <br /> 10