"December 1970." "[Prepared] for the Federal Water Quality Administration, Environmental Protection Agency." Includes bibliographical references (pages 61-62). U.S. Environment Protection Agency Grant No. Contract Number: WPD-199-01-67.

A field demonstration lagoon was operated at Virginia Oak Tannery, Inc., Luray, Virginia to evaluate the effectiveness of an anaerobic-aerobic lagoon in treating spent vegetable tannins blended with batepool and soak waste waters. The anaerobic-aerobic lagoon system was used to treat combined waste streams with a BODb5s concentration of approximately 1000 mg/Á. Aeration and volume of the lagoon were fixed and flow to the system was varied. The system load varied by increasing the flow so as to observe five operational phases. Operational phases were designed to cause to system to go from aerobic conditions to anaerobic-aerobic. After reaching anaerobic-aerobic conditions, doubling the BODb5s load did not result in a significant decrease in BODb5s removal efficiency. Efficiency, measured in terms of soluble BODb5s, at a BODb5s load of 17.3 lbs/1000 ftp3s/day (anaerobic-aerobic condition) was 81 percent compared to a 92 percent efficiency for a BODb5s load of 4.5 lbs/1000 ftp3s/day (aerobic conditions). The final load on the system under anaerobic-aerobic conditions was 1.73 lbs of BODb5s/1000 ftp3s/day/B.hp. During this loading condition soluble BODb5s and soluble COD removal efficiencies of 81 and 58 percent, respectively, were observed.