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exceedences out of the total number of samples (i.e., 1/2 indicates one . exceedence out of two samples). Below is a summary of standards that were exceeded. Given in parenthesis is the source and use of each standard. Parameter Number of Wells boron (CDOH, irrigation). 1 pH (CDOH, irrigation) 1 i irons, (CDOH, irrigation) 2 manganese (CDOH, irrigation) 12 ~ - In addiaion,~ a. total of five samples ,(from three wells), had cadmium _ values that were less than an. elevated detection limit (20 ug/1~ vs. a_ normal detection limit of 3 ugLl), which was higher than the CDOH standard of 10 ug/1. Likewise, three samples from the same wells had.. lead! values that were less than an elevated detection limit (200 ug/1 f- vs. ;a normal detection limit of 20 ug/1), which was higher than the cDOH ~ standard of 100 ug/1. The cause of these elevated detection limits was ~ ; I a decision by the laboratory to dilute ihe_samples prior to analyses in j order to reduce the effects of interferences primarily, high salinity). i Elevated levels of iron may be attributed to natural (i: e., not mining related) conditions, since elevated levels for that parameter are not normally found in spoil wells at the adjacent Seneca II Mine. The two bedrock wells (WW19 and WTC201) that often exhibit high levels may have higher than usual concentrations of iron pyrite in the rock. Well WTCZOI (Trout Creek Sandstone, shop well) often displays high iron values, but does not display an increasing trend. Wadge coal well WW14 started displaying high iron values in 1998 and displays an increasing trend. The high Ie vels of iron displayed in the one alluvial well (WHAL7-2) may be the result of organic matter and plant debris present in the alluvium (Hem, 1989, pg. 77) . All wells with high iron values exist within the Seneca II-W permit boundary. High manganese values may, in part, be due to recharge from the spoil . aquifer, although high values are often common, especially in alluvial 10