AbstractA proposal dealing with the Department of Defense's (DOD) counterpart to a municipal sewage treatment plant was one of the concessions sought by the DOD in return for the imposition of punitive civil penalties under the Federal Facilities Compliance Act (FFCA). Municipal sewage treatment plants, or Publicly Owned Treatment Works (POTWs), are usually regulated under the National Pollutant Discharge Elimination System (NPDES) permit system of the Clean Water Act1and not under the Resource Conservation and Recovery Act (RCRA).2This article discusses a key exclusion from and the controversy of RCRA's definition of “solid waste.”3That definition identifies substances and, by implication, activities regulated by RCRA. Though exceptionally broad, this definition specifically excludes “solid or dissolved material in domestic sewage.”4This is commonly called the domestic sewage exclusio