This paper outlines the results of a hazardous waste characterization study prepared as part of a Resource Conservation and Recovery Act (RCRA) Delisting Petition for spent granular activated carbon generated by the South Adams County Water and Sanitation District. The study analytically evaluated the spent GAC for numerous characteristics, including contaminant constituent concentrations, toxicity characteristic leaching procedure (TCLP) tests, radiological parameters, and other potential hazardous waste characteristics. The study also empirically and theoretically evaluated the potential for contaminants to be released to the environment if the GAC is improperly managed or if any one of six worst-case accident scenarios occurred. Most importantly, the study used the results to develop a theoretical basis for projecting the increased contamination concentrations that would be necessary for the spent GAC to fail the TCLP test and, thereby, be classified as a hazardous waste.