55 



conductivity was around 3000 |is/cm. 



The levels of both vanadium and chromium have been in the 0.1 to 0.4 mg/L range. 

 During the winter of 1990/91 , test results for both parameters decreased sharply below 

 0.1 mg/L but have since increased to near previous levels. From 1 984 to 1 988, a modest 

 increasing trend was noted for molybdenum with steady values of between 3.0 and 4.0 

 mg/L for 1988 to 1990. From late 1990 to mid-1991 , values were declining but by the 

 end of 1991 molybdenum results had returned to pre-1990 levels. 



Fluoride and sodium appear to have followed the same pattern as the other parameters 

 during 1990 and 1991. From 1983 to 1989, fluoride results moved between the 5 and 

 15 mg/L levels with the occasional spike to 25 mg/L. In early 1990, results dropped 

 sharply and remained low to late 1991 when fluoride results started to move up. From 

 1988, sodium results have remained stable at about 600 mg/L. In the second quarter of 

 1991, sodium results dropped to 446 mg/L, but like fluoride, sodium results were 

 increasing by the end of the year. The results for chromium, sodium, vanadium, fluoride 

 and molybdenum do not appear to be strongly influenced by polishing pond water 

 volumes. 



Sulphate results have historically moved between a wide range of 500 to 1500 mg/L. 

 Contrary to what was observed for other parameters, there is a good relationship between 

 sulphate results and polishing pond volumes. 



