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ASH LAGOON QUALITY AND QUANTIiy 



The ash lagoon system at the Poplar River Power Station continues 

 to be operated on a closed system basis with no discharges to 

 surface waters. During 1987, most of the sluiced ash was directed 

 to the north end of Ash Lagoon No. 1, The normal operation has 

 been the use of Ash Lagoon No. 1, Ash Lagoon No. 2 and the 

 Polishing Lagoon in series operation. Water from the Polishing 

 Lagoon is returned to the plant for ash sluicing. During 1987, 

 maximum and minimum water depths in Ash Lagoon No . 1 and 2 and the 

 Polishing Lagoon ranged between 6.2 and 5.2, 5.6 and 4.4, and 5.2 

 and 4.2 m, respectively. 



Ash Lagoon No. 3 North was put into service for approximately three 

 weeks during September, 1987. The maximum water depth in Ash 

 Lagoon No. 3 North was 1.8 m during 1987. 



Seepage calculations were made in 1987 using the methods developed 

 by T.A. Priekett, P.E., of Urbana, Illinois. Results of the 

 calculations for Ash Lagoons No. 1, 2 and 3 and the Polishing 

 Lagoon are shown in Table 7. In 1987, seepage calculations were 

 included for Ash Lagoon No. 3 for the first time. 



Table 7 . SPC-PRPSS Ash System, 1987 Calculated Seepage Rates 



Source Rate (L/s) 



Polishing Lagoon 0.278 



Ash Lagoon No. 1 0.172 



Ash Lagoon No. 2 0.299 



Ash Lagoon No. 3 0.002 



Total Seepage 0.751 



