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Creek are not monitored. An impact to surface water quality was anticipated in Trout Creek. The amount was anticipated to vary significantly, and is greatly dependent upon flows (seasonal and irrigation calls) in Trout Creek as variations in spoil spring flows are more moderated. TDS values were expected to rise as high as ],186 mg/1 at some time during the mining and postmining era at the Edna Mine (PAP, page 2.SA-7). Sulfate concentrations were expected to reach an upper limit of approximately 842 mg/1 (PAP page 2.SB-3) in Trout Creek. Monitoring station TR-D is below mining activity on Trout Creek. TDS values reported for TR-D ranged from 940 to 160 mg/1 during the 2006 water yeaz. Sulfate concentration ranged from 560 to 100 mg/1 at this surface water-monitoring site. A summary statement that all values for TDS in Trout Creek are consistent with the probable hydrologic consequences projections is made on page 11 of the AHR. This review validates this statement, and also finds that sulfate concentrations were within the anticipated range. An impact to alluvial groundwater of Trout Creek was anticipated. TDS in alluvial materials was expected to rise to 2000 - 3000 mg/1(PAP page 2.5-97). Alluvial groundwater is monitored at three stations, TR-1.5 above mining, TR-3 at the northern limit of mining (downstream), and TR- 4approximately amile below mining. TDS values in alluvial monitoring well TR-1.5 ranged from 4370 to 4600 during the 2006 water year. TDS values in TR-1.5 have risen from 1020 in 09/23/99 to as high as 4800 in July of 2005, but appear to be leveling off in the mid - to -upper 4000s. There is only speculation (in the PAP) for high and rising TDS values in TR-1.5. TDS values in TR-3 ranged from 400 to 550 mg/1, and in TR-4 from 710 to 780 mg/1. Impacts to alluvial groundwater of Trout Creek are within those predicted. No impact to alluvial groundwater in Oak Creek was anticipated (PAP page 2.5-95b), and no groundwater monitoring was conducted. No probable hydrologic consequence was predicted in the PAP for bedrock groundwater. Bedrock aquifers that abut spoil backfill probably aze too impermeable to transmit any significant amount of leachate. Those bedrock units in close proximity to the floor of the pit are exposed (or covered with a shallow mantle) below the pit and above Trout Creek. However, a monitoring station (an existing, privately-owned well) was established in the Trout Creek Sandstone (a unit some 150 feet or more below the pit floor) directly downdip of mining activity. Monitoring from 1995 indicates that TDS values have remained consistent in a range from 440 to 930 mg/l, with no apparent rising trend. Monitoring at this station was not (due to equipment problems - no power) accomplished during the 2004 water year. Repairs were made, and a single measurement in 2005 was 900 mg/1. Page 6