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I ~ mg/L during the first calendar quarter of 2001. The ammonia concentrations this water yeaz for well 95-1 returned to lower levels, only slightly elevated from historic conditions and remamed consistent through this water yeaz. Bicarbonate Bicarbonate concentrations at the three wells remain within the historic ranges for each well. Well 17-B exhibited an initial rise, followed by a drop in concentrations this water year that is also found in water years 1995, 1997, and 2002 during the first calendaz quarter of the water year. Well 94-1 showed an increase in concentrations during the period from water year 1997 through water yeaz 2000, but that trend reversed during water year 2001 within levels remaining consistent with the water yeaz 2001 levels this yeaz. Bicarbonate concentrations at well 95-1 decreased over the same period and are increasing slowly at this time. This may be indicative of a slowly moving concentration of bicarbonate ions downgradient through the mine over the past several years; however, the concentrations through the azea have not exceeded historic ranges. The seasonal elevation and decrease noted in well 17-$ was also apparent in well 95-1 this water year. Calcium Calcium concentrations were slightly elevated during the dry period during the first quarter and fell during the second quarter this water year within all wells. This may be the ~, result of increased concentrations during the drought and decreased concentrations during the recharge from a significant snow event and corresponding rechazge upgradient. Well ] 7-B continues to exhibit consistent concentrations between 9.2 and 20.4 mg/L. We1194- 1 exhibits historically wide fluctuations in calcium concentrations ranging from 23.9 mg/L (fourth quarter W.Y. 1997) to 160.0 mg/L (first quarter W.Y. 1997), Concentrations are characteristically high during fall and wiener attenuating during the spring and summer months. For the past two water years, well 94-1 concentrations have remained low and consistent. Well 95-1 showed wide fluctuations in calcium concentrations during water yeazs 1997 and 1998, but since then concentrations have become very consistent. Chloride Chloride concentrations in welts 17-B and 94-1 have remained low for the past four water years, near detectable limits. Chloride concentrations were elevated in well 95-1 during water years 1999 and 2000. The last two water years chloride concentrations decreased, though concentrations in well 95-1 remain at 1997-19981evels. L'On Iron concentrations were elevated during the fourth calendar quarter of 2000 and second calendar quarter of 2002, significantly so for wells 17-B and 95-1. During the later half of water year 2002, all wells revealed reduced iron concentrations, leading to the conclusion Gabon Junction Mlro Page tO Mnual HyArologlc ReporC far Water Year 2003