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At locations 2b (piezometer C718) and 2c (piezometer C719), near the 

 north end of the Polishing Pond, there have been no consistent 

 water quality trends during the period of record. Although these two 

 sites are close to each other, and are both screened in till, there 

 are large differences in the chemical makeup of their waters. Most 

 notable is the sulphate concentration in C719, which is some 18 times 

 larger than that in C718. The uranium level in C719 peaked in April 

 1986 at 460 Ug/L; no long term trend in the uranium values from 

 that piezometer is apparent. 



At location 8a, west of cell No. 1 of the Ash Lagoon, piezometers 

 C726A and C726C are completed in till. Although there are consistent 

 differences in the quality of water from these two piezometers, no 

 trends are evident. 



At location 9a at the west end of the Pollstilng Pond, piezometer 

 C728A has remained dry since 1980. Piezometers C728B and C728C show 

 no consistent trends during the period of record. The uranium concen- 

 trations in both piezometers were fairly stable during 1986. At the 

 end of 1984, an increasing trend in uranium concentration appeared 

 to be developing in C728C, after showing an increase in the dissolved 

 constituents. However, the 1985 and 1986 data show that the uranium 

 levels have stabilized within the range 20 to 40 Ug/L. Piezometer 

 C728D has remained dry. 



Piezometer C534 Is screened in till to the south of the Ash Lagoon. 

 Ground-water quality is inferior in comparison with locations 8a and 

 9a. Total dissolved solids concentrations are near 4,500 mg/L. 

 There is no evidence of long-term trends in water quality. 



