Class a biosolids production by a low-cost conventional technology

Encouraged by a finding that the pathogen analyses of numerous samples of t he final product of the Metropolitan Water Reclamation District of Greater Chicago, Illinois (District), met the U.S. Environmental Protection Agency (U,S. EPA) Class A criteria, the District optimized and codified the operat ion of its sludge processing trains (SPTs), submitted a petition to the U.S . EPA Pathogen Equivalency Committee for obtaining certification of its SPT s as equivalent to a process to further reduce pathogens, and conducted a 3 -year full-scale study. The objective of the study was to determine whether or not the District's SPTs consistently produced a Class A biosolids final product. The primary conclusion drawn from this optimized and codified ope ration study was that all batches of the final air-dried product complied w ith the Class A criteria as specified by U.S. EPA in the Part 503 regulatio ns.