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• 3.2.2 Springs <br />There is one active spring on the mine site area, known as the No. 1 Strip Pit Discharge, or 1SP. There are a <br />few other springs and local permanent "damp spots" in the area; however, their combined flow is normally <br />less than 10 gpm and is therefore not significant. 1SP Discharge is a CDPS monitoring point (Outfall 022). <br />There is no sediment pond associated with this spring. Spring water runs down a narrow path through a <br />vegetative filter and discharges directly to the Williams Fork River. The POR discharges for the 1SP are <br />presented in Figure 23 and the 2006 discharge measurements are presented on Figure 24, respectively. The <br />discharge from 1SP increased significantly back in 1989. This may have been due to seepage from the ditch <br />that conveys the 7 North Angle discharge (measured at site 9P3, a.k.a. CDPS Outfall 024)). Site 9P3 <br />discharge began in January of 1989, and has been sporadic. Site 9P3 Discharge rates from 1990 through <br />2003 are lower. 9P3 has not discharge since 2003. Nevertheless, snowmelt and ditch seepage both appear to <br />have some influence on 1SP discharge, as the discharge typically drops to just a few gpm from January <br />through May with a small peak typically in March coinciding with spring runoff. 1SP is typically dry from <br />July through November. <br />Summaries of the water quality data for this spring are presented in Tables 31 and 32. A plot of POR total <br />dissolved solids for 1SP is presented in Figure 25 and POR iron concentrations are presented on Figure 26. <br />Figure 25 indicates TDS concentrations that are consistent with historic concentrations. Figure 26 illustrates <br />• the variable nature of total recoverable iron concentrations in ISP discharge. Since 2002 there has been a <br />gentle upward trend in iron concentrations, however these levels are still within historic ranges seen for this <br />site. BTU EC will continue to monitor this trend. <br />3.2.3 Ponds <br />With the exception of Outfall 003 (discussed under section 3.1.2), there was no recorded discharge from [he <br />other on-site sediment ponds in 2006. <br />4.0 SUMMARY AND CONCLUSIONS <br />The subject mine site ceased active mining operations in 1995. The mine was subsequently placed in <br />Temporary Cessation. The mine has been inactive from 1995 to date, thus total mined acreage has no[ <br />changed. The Temporary Cessation status ended in the second quarter of 2006, when BTU EC re-activated <br />full water monitoring activities in anticipation of future re-activation of the mine site, and because a bond <br />release application was also being contemplated for the Utah Tract and Williams Fork Strip Pit portions of the <br />mine property. No significant, unpredicted, or adverse environmental impacts were noted during hydrologic <br />monitoring for 2006. DRMS monitoring requirements were met. <br />Page 7 <br />. I: \Env\Empire\AHR\2006\Tes[\Empire2006AHR.doc <br />