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Ground Water Quality. Table 3 provides a summary of ground water <br />monitoring sites at the Yoast Mine. Table 4a and 4b show the new (2010) <br />ground water parameter lists. Appendix C provides all ground water <br />quality data collected during this year, along with sampling remarks. <br />This is followed by a plot of TDS versus time for the entire period of <br />record. The regression line on this plot is generated by a method known <br />as LOWESS which is an acronym from Locally Weighted Scatter plot <br />Smoothing (Cleveland, 1979) . Unless otherwise noted, smoothness factor <br />(SF) of 1 (on a scale of 0 to 1) was used, which gives maximum <br />smoothing. <br />A statistical report representing baseline (i.e., premining) data for <br />each well (when available) is presented in Appendix C1 of the 2010 AHR. <br />On this statistics report, "censored data" refers to analytical values <br />that were below the detection limit, which were censored from the <br />min/max/mean calculations. The time frame for baseline conditions is <br />listed under "conditions specified" at the bottom of each page. <br />- Alluvium. One well, YAAL14, monitors water quality in the Annand Draw <br />alluvium. TDS values for this well display an increasing trend. However, <br />the peak value occurred in May 2008. <br />One well, YGAL16, monitors water quality in the Grassy Creek alluvium. <br />This well is located immediately below NPDES11 on a Grassy Creek <br />tributary. It displays an increasing TDS trend. However, the peak value <br />occurred in May 2011. <br />Two wells, YSAL1 and 3, monitor water quality in the Sage Creek <br />alluvium. Well 1 is the furthest downstream well for the Yoast Mine. It <br />displays an increasing TDS trend, with the peak value occurring in <br />October 2007. Well 3 is upstream of Well 1, and is located along Sage <br />Creek, just below the discharge from NPDESI2. It displays an increasing <br />TDS. However, the peak value occurred in May 2011. <br />- Wadge Overburden. Well YOV30 displays an increasing TDS trend. <br />However, the peak values occurred in September 1992 and June 2011. <br />3 <br />