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 ASH LAGOON QUANTITY AND QUALITY 



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 1988, the sluiced ash was generally directed to 

 either the north end of Lagoon No . 1 or the southeast corner of 

 Lagoon No. 3. For the former, the operating series sequence is Ash 

 Lagoon No. 1, Ash Lagoon No. 2 and the polishing pond. When ash is 

 directed to Ash Lagoon No. 3, the normal series operation is Ash 

 Lagoon No. 3, Ash Lagoon No. 2 and the polishing pond. Water from 

 the polishing pond is returned to the plant for sluicing. 



During 1988, maximum and minimum water depths were 5.3 and 4.6 m 

 in Ash Lagoon No. 1, 4.6 and 3.2 m in Ash Lagoon No. 2, 1.6 and 1.2 

 m in Ash Lagoon No. 3, and 4.6 and 2.3 m in the Polishing Lagoon. 



Seepage calculations were made in 1988 using the methods developed by 

 T.A. Prickett, 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 6. 



Table 6. Poplar River Power Station Ash System, 1988 Calculated 

 Seepage Rates 



Source Rate (L/s) 



Polishing Lagoon 0.313 



Ash Lagoon No. 1 0.246 



Ash Lagoon No. 2 0.317 



Ash Lagoon No. 3 0.022 



Total Seepage 0.898 



