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Water Quality in the Empress Gravels 



Figure 13 shows that there are no significant trends in total 

 dissolved solids in the Empress Gravels. Piezometer C726E, located 

 at the west side of Ash Lagoon No. 1, displays a greater 

 variability in TDS concentration than the other Empress 

 piezometers , possibly due to variable recharge from the overlying 

 tills under certain conditions. 



Ground water quality characteristics of the Empress gravels, 

 located to the north Ash Lagoon No. 2 (C726) are generally similar 

 to C728E, west of the Polishing Lagoon. Boron remains consistently 

 higher in C728E (1.2 mg/L) than in C726E (0.7 mg/L) . At location 

 C533, south of Ash Lagoon No. 1, there are no trends evident in any 

 of the water quality parameters monitored. 



In C741, to the southwest of Morrison Dam, dissolved aluminum has 

 decreased from more than 1 mg/L in 1981 to the detection limit 

 (0.01 mg/L) in 1987. In C742, one kilometre south, it has 

 decreased from 0.46 over the same time period. In C742 Boron has 

 decreased from 0.99 mg/L in 1983 to 0.56 mg/L in July, 1987. 



The trends in the concentration of aluminum and other species over 

 time are not observed over short intervals because fluctuations in 

 concentrations occur from year to year that may mask the long-term 

 trends . 



