At location 9a, at the west end of the polishing pond, piezometer 

 C728B shows somewhat elevated levels of uranium in the July 5, 1984 

 and October 12, 1984 samplings. These higher than usual values have 

 occurred sporadically in samplings of previous years (for instance 

 October 1982), but are not considered to be representative of any 

 significant trend. Similar variability in uranium concentrations 

 during 1984 is noted for piezometer C728C. Significant concentration 

 trends with respect to uranium or to any other parameters in C728B or 

 C728C are not apparent. 



At location 8a, at the western edge of the ash lagoon No. 1, monitor- 

 ing was discontinued in piezometer C726B after 1983, because of 

 extremely high levels of various ions measured, and because of the 

 extreme variability in concentration observed over time. It was 

 assumed that these high concentrations and extreme variability were 

 of a natural origin. Other piezometers completed in till at location 

 8a (C726A, C726C) display much more moderate hydrochemical variation. 

 No particular trends in water quality have been noted over the period 

 of record for either piezometer. 



In piezometer C534, monitoring was continued in 1984. Iron and zinc 

 analyses were discontinued, due to contamination from the galvanized 

 steel casing. No significant trends were evident in any parameter 

 over the entire period of record. 



Water Quality in the Empress Gravels 



The Empress Gravels form an important aquifer in the East Poplar 

 River Basin. The associated ground waters are of a moderately high 



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