A laboratory model (1:10 scale) of an operational field oxidation ditch used in beef cattle production was utilized in survival and detection studies of Leptospira pomona and Salmonella typhimurium. Minnesota summer (20C) and winter (2C) temperatures, pH, and dissolved oxygen of field ditch manure slurry were simulated in laboratory model studies of manure slurry, effluent, and sludge. Maximum leptospiral survival times of 138 days (summer) and 18 days (winter) in the slurry were measured. Salmonella survival of 47 days in slurry and 87 days in sludge (winter), and 17 days in slurry (summer) were measured. Adequate laboratory cultural detection and isolation techniques were developed to measure survival. Findings from simulated studies in a second laboratory model were used to separate materials for recycling.

Prepared for Office of Research and Development, U.S. Environmental Protection Agency, Washington, D.C., under the Grant no. EP-00302, Program element no. ID2063. Project officer: Mirdza L. Peterson, Solid Waste Research Laboratory, National Environmental Research Center, Cincinnati, Ohio. "Report no. EPA-670/2-73-051." "PB-222 337." Includes bibliographical references (pages 83-89). Microfiche.