Process Equivalency Under 503: How to Get There

Over the last several years, there has been a growing interest in using alternative technologies for disinfection of municipal sludge destined for land application. The 503 regulations include provisions for permitting the use of alternative and innovative treatment technologies. Under these provisions, the permitting authority is responsible for determining if a specific sludge treatment process meets equivalency criteria. EPA's Pathogen Equivalency Committee (PEC) is a multidisciplinary group of engineers and scientists who provide regulatory officials with guidance and assistance in making equivalency determinations. Furthermore, the PEC is responsible for making national equivalency recommendations for biosolids treatment processes. Since the inception of the regulation, a number of technologies have been identified as “equivalent” processes based upon demonstrating their consistent effectiveness in reducing the number of bacteria, viruses and viable helminth ova in municipal sludges. In order to ensure that a process can consistently meet equivalency criteria, those desiring to use such technologies must provide adequate documentation supporting process effectiveness. The PEC has updated the criteria it uses to make recommendations of equivalency on innovative or alternative sludge pathogen reduction processes. To assist new applicants through the equivalency recommendation process, the PEC has provided a website. This site clearly presents the criteria used by the PEC for making equivalency recommendations and provides guidance for technology evaluation, testing and documentation. The main steps of the equivalency recommendation process are discussed through the introduction of the website materials. During the presentation we identify technologies that have been designated as “equivalent,” and those which are currently going through this process. Also, we discuss some key points to consider as we go through the equivalency determination/documentation process.