ASH LAGOON QUALITY AND QUANTITY 



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 1985, most of the sluiced ash was directed into Ash Lagoon No. 2. 

 The normal operation has been using Ash Lagoon No. 2 and the polishing 

 pond in series. Water from the polishing pond is returned to the plant 

 for ash sluicing. End of quarter water depths in Ash Lagoons No. 1 and 2 

 were in the 3.2 - 6.1 m and 3.2 - 4.2 m ranges respectively. A small 

 amount of ash and water were slurried to Ash Lagoon No. 3 to increase 

 water levels and, to protect its lining while this lagoon was not in use. 



Seepage calculations were carried out in 1985 using the methods developed 

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

 calculations for Ash Lagoons No. 1 and 2 and the polishing pond are as 

 follows: 



Table 7 

 Calculated Seepage Rates 



Source Rate (L/s) 



Polishing Pond 0.239 



Ash Lagoon No. 1 0.172 



Ash Lagoon No. 2 0.339 



Total Seepage 0.750 



- 28 



