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down gradient movement of spoil water. <br />Wadge overburden well 006-82-74C water levels continue to climb indicating recovery of the Wadge <br />overburden unit in the area of the Foidel Creek mine portal. TDS in [his well has generally declined <br />which could possibly be explained by a flow direction change in [he water [hat is recharging this well. <br />Previous flow direction (NW) caused by underground mining in the Southwest Mine District <br />(SWMD) of the Foidel Creek mine would cause water from the surface mine spoil aquifer to recharge <br />this well. With the SWMD now flooded and mining in the Eastern Mining District (EMD) acting as a <br />dewatering well, flow direction has likely changed to northeast, causing recharge to this well from <br />water moving from an undisturbed area of the Wadge overburden unit. <br />No significant changes in alluvial water levels were noted. Field conductivity values for well 006- <br />AW-2 were measured significantly lower than values the previous year. This may be due to the <br />general lack of mine discharge from the adjacent Foidel Creek mine over the reporting period. <br />Seasonal variations in water level and the timing of those changes are within normal ranges. <br />Surface Water <br />Water quality upstream of the mine is affected by spoil springs, which is predicted in the probable <br />hydrologic consequence section of the permit. Discharge of spoil spring water through the sediment <br />ponds A, D, and F continue to affect the overall quality of surface waters in the immediate area. EC <br />values downstream of the FoideUMiddle Creek confluence on Trout Creek were historically 300-400 <br />umhos/cm but are now 500-600 umhos/cm during low Flow periods. Mean discharge from NPDES <br />outfalls 39, 84, and 87 totaled 1.77 cfs in 1999 as compazed [o Table 1 lA estimates (permit #C-81- <br />071) of 1.72 cfs. Although the TDS of the actual discharge is higher than 3246 mg/1 (more like 3700 <br />mg/I), [he downstream impacts are less than predicted. September TDS upstream was 280 mg/I and <br />downstream was 310 mg/1 resulting in no impact to irrigation or agricultural use. TDS levels do not <br />appear to be increasing or showing any trends towards degradation of quality beyond current levels as <br />a result of mining under this permit(#C-81-071). <br />Mining has no significant affect on the amount of surface water in the area. It is likely [ha[ runoff <br />from the reclaimed areas increases the amount of water to the surface water system below the mine. <br />Seasonal variation from one year [o the next can be dramatic, based mainly on the amount of <br />snowpack each season. Spoil springs have modified Foidel Creek and changed i[ from apre-mine <br />intermittent stream to a post-mine perennial stream. No negative identifiable impact is apparent from <br />review of the data. Surface waters downstream of mining do not show regular or chronic <br />exceedances of the applicable receiving stream standazds established for the system. <br />This concludes my review of the 1999 AHR. Please forward the AHR issues to the operator. <br />CC: Dan Hernandez <br />