s 



- 58 - 



North Side of Lagoon 



Location 2a (North of the Polishing Pond) 



Piezometer C712B which is in the intra till sand, shows increasing B 

 levels in Figure 42. TDS results have gradually decreased after signifi- 

 cantly increasing from 1980 to 1983 as shown in Figure 43. CI levels 

 show a decreasing trend in Figure 44. The sample result for zinc (Zn) in 

 1990 decreased to concentrations obtained in 1986 and 1987 as shown in 

 Figure 45. Water levels have been steady as indicated in Figure 46. 



A review of the leachate movement at piezometer C712B was done during the 

 leachate review of the ash lagoons conducted by Clifton Associated Ltd. 

 for Sask Power. The leachate review was combined with the seepage calcu- 

 lation review and forwarded to the Poplar River Bilateral Monitoring Com- 

 mittee members for comments. The leachate review noted that a slug of 

 leachate is probably affecting the sand lens piezometers. 



C712B 



16 



14 

 12 + 



10 

 8 



6 4 

 4 

 2 4- 



5/25/79 10/6/80 2/18/82 7/3/83 11/14/84 3/29/86 8/11/87 12/23/88 5/7/90 9/19/91 



SAMPLE DATE RANGE 



Figure 42. — Boron in intra-till sand piezometer C712B, 



