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With regard to the Trout Creek drainage, spring and seep flows increase with snow melt and <br />then taper off, indicating that backfilled areas have become spoil aquifers in equilibrium with <br />charge and discharge cycles. As revegetation of reclaimed areas become more and more <br />representative of pre-mining vegetation cover, and as reclaimed surfaces are similar in <br />topography to pre-mining conditions, surface run-off likely approaches pre-mining levels. The <br />difference at this time is that surface runoff is collected and directed to sedimentation ponds <br />with point discharges. For most of the site, these point discharges are representative of pre- <br />mining drainage discharges, and the ponds have been permitted as permanent features. As <br />noted during on the ground inspection and through monthly monitoring reports, ponds are <br />generally full with inflow a relatively close equivalent to discharge. Any infiltration of <br />precipitation over and above pre-mining conditions is likely recovered in the spoil spring <br />discharges. <br />Disturbed areas of the Oak Creek drainage have been reclaimed to the requirements of the <br />reclamation plan and sedimentation ponds have been removed. There is no post-mining <br />condition that would deplete runoff from these areas from pre-mining conditions. Flows in <br />Oak Creek are not monitored. <br />The streamflow during 2009 increased compared with previous years with a slight decline from <br />2008. The flow record shows a peak flow occurred in May 2009. The runoff was higher than <br />previous years due to more snowpack and the onset of warmer temperatures occurring later in <br />the springs. <br />2. PHC: Sulfate concentrations were expected to reach an upper limit of approximately 842 <br />mg/l (PAP page 2.513-3). <br />Sulfate concentrations were monitored at sites TR-A, TR-B, TR-C and TR-D for the period of <br />record. The lowest sulfate concentration in 2009 was recorded at monitoring site TR-A <br />numerous times during the reporting year with a value of <10 mg/L and the high were recorded <br />at monitoring site TR-C and TR-D in April with a value of 400 mg/L. The report finds that <br />sulfate concentrations were within the anticipated range. <br />3. PHC: TDS in alluvial materials was expected to rise to 2000-3000 mg/l (PAP page 2.5-97). <br />Alluvial groundwater is monitored at three stations, TR-1.5 above mining, TR-3 at the northern <br />limit of mining (downstream), and TR-4 approximately a mile below mining. TDS <br />concentrations exhibited the same tends in 2009 as found during the previous years of <br />monitoring. The lowest TDS concentration in 2009 was recorded at monitoring well TR-3 in <br />June with a value of 520 mg/L and the high was recorded at monitoring well TR-1.5 in May <br />with a value of 4100 mg/L. TDS values have risen from 1020 in 1999 to as high as 4920 in <br />September of 2008, but appear to be leveling off in the mid-to-upper 4000s. Page 11 of the <br />AHR gives the possibility that the alluvium in the area is reflecting upstream alluvial water <br />containing high levels of TDS, possibly from an old abandon underground mine up the Little <br />Trout Creek Drainage. Impacts to alluvial groundwater of Trout Creek are within those <br />predicted.