Few desirable methods exist for disposing of the sludge that is periodically pumped from septic tanks. This report describes the results obtained from a pilot study of one alternative septage treatment method-lime stabilization followed by covered sand-bed dewatering. The study was conducted in two phases. Phase I (4 months) consisted of the general, chemical, and biological characterizations of the incoming septage. Attempts were made to thicken the material via stirring, polyelectrolyte addition, and lime addition. Phase II (9 months) concerned itself with the application of lime septage onto covered sand beds. Four experimental runs were conducted to assess the feasibility of such an approach. The septage was limed to pH 10.5, 11.0, and 11.5 and applied at 8-in (20.3-cm) depths. Underdrainage and cake characteristics were monitored and practical sand-bed application rates were determined. A materials balance of chemical constituents around the system was made. A cost estimate for the treatment of septage at small treatment plants via this method is included.

Includes bibliographical references (pages 51-52).