Laserfiche WebLink
pond that occurred in the summer of 1996 and the fall of 1997. An <br />upstream presettling pond was added in March 1998. The principle <br />spillway elevation was changed again, and the dewatering orifice <br />removed, in August 1998. In August 2003, an 18-inch riser pipe was <br />installed on the discharge culvert, and the presettling pond was <br />removed. Additional dredging (and dewatering) occurred in the fall of <br />2004. Also affecting discharges from this pond are the pumping of water <br />from this pond for water trucks and the pumping of water into this pond <br />from the mine water supply well (WTC201). <br />Review of the TDS plot indicates an increasing trend due to runoff from <br />mine spoils. Baseline data for this site (WSH6) has been provided in <br />Appendix E1. <br />- Surface Water Site SW-S2W-FG1 (WSHF1). This site is located on <br />Hubberson Gulch downstream of the 006 Gulch confluence. It has been <br />monitored since July 1979. Irrigation ditches were established adjacent <br />this site in July 1999. The TDS plot indicates an increasing trend. <br />Baseline water quality statistics have been provided in Appendix E1. The <br />Seneca II-W PHC, Table 17-42b, predicts an irrigation season (June- <br />September) average TDS value of 2527 mg/l for this site, while a value <br />of 1765 mg/l was observed this year. <br />- NPDES 005 (NPDES5). This sediment pond is located in the north mining <br />area on a tributary to Dry Creek referred to as the 005 Gulch. <br />Constructio n of this pond was completed in July 1992 and the first <br />discharge occurred on April 22, 1993. This pond was dredged in the <br />summers of 1998 and 2001. The water year average flows values since this <br />pond began to discharge are: <br />2008 0.083 cfs (monthly measurements) <br />2007 0.038 cfs (monthly measurements) <br />2006 0.038 cfs (monthly measurements) <br />2005 0.021 cfs (monthly measurements) <br />2004 0.017 cfs (monthly measurements) <br />. 2003 0.026 cfs (monthly measurements) <br />2002 0.016 cfs " <br />15