What do the Viking mission to Mars and the "scrubber" waste disposal system for CAPCO's Bruce Mansfield Plant have in common?

Both feats were deemed one of the ten outstanding engineering achievements of 1976 by the National Society of Professional Engineers (NSPE).

The Mansfield waste disposal system, designed and developed for the Penn Power-operated plant by the Dravo Corporation of Pittsburgh, handles a resultant sludge removed from the plant's stack gases by its "wet scrubber" air quality control system. At full capacity, over 7,600 tons of sludge, containing fly ash and calcium salts are produced each day for each of the plant's 825,000 kilowatt coal-fired units.

The $90 million waste disposal system is the largest of its kind in the world. Its three principal components are (1) a treatment and pumping facility at the Shippingport, PA plant site; (2) a sevenmile underground pipeline transport system and (3) a 1,330-acre impoundment area that includes the "largest earth and rock-fill embankment dam in the Eastern United States."

At the plant site the "scrubber" sludge is thickened slightly and then treated with a Dravo-developed hardening agent. The

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