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lines, which were siphoning water out of Pond 002, were capped off on <br />July 7, 2010. Additional ponds (the Upper and Lower Sumps) were <br />constructed above this pond in 2011. Review of the TDS plot indicates an <br />increasing trend, with the peak value occurring in February 2013. <br />Grassy Creek Drainage. Five required monitoring sites lie within the <br />Grassy Creek drainage. They are (from upstream to downstream): YSGF5, <br />SSG1, NPDES Discharge Point 003, (also known as the Shop Reservoir or <br />the Northwest Impoundment, located just north of the mine shop area), <br />SSG2 (located approximately 0.1 mile downstream of where NPDES3 <br />discharges into Grassy Creek) and, finally, YSG5 (the furthest <br />downstream site). <br />- Surface Water Site YSGF5. This site was initially part of the <br />monitoring program for Seneca Coal Company's Yoast Mine, and is now also <br />part of the PSCM program. It is in the upper part of Grassy Creek, just <br />below the confluence of the Yoast NPDES Pond 011 discharges. Review of <br />the TDS plot indicates a slightly increasing trend, with the peak value <br />occurring in August 2013. <br />- Surface Water Site SW -S2 -1 (SSG1). This site monitors Grassy Creek <br />upstream of mining at the Seneca II Mine. Review of the TDS plot <br />indicates a stable trend (SF 0.5). <br />- NPDES Discharge Point 003 (NPDES3). Hydrographs presented in Appendix <br />D show that flow has increased at this site since September 18, 1984, <br />when operation of the truck wash system began. During operation, water <br />was siphoned from the Wadge Impoundment (NPDES2) into a holding pond. <br />Overflow from the holding pond was diverted into the shop ditch, which <br />flows into NPDES3. Water was pumped from the holding pond to the wash <br />rack, drained into a settling pond, and then into the same shop ditch. <br />This operation increased the flow at NPDES3 while decreasing the flow at <br />NPDES2. <br />Other events have affected the long -term hydrograph at NPDES3. They <br />include the diversion away from NPDES3 of the runoff from an inactive <br />13 <br />