Although PCBs technically qualify as hazardous waste under the Resource Conservation and Recovery Act’s (RCRA’s) definition, they’re specifically excluded from RCRA regulation as hazardous waste because PCBs are regulated under the Toxic Substances Control Act (TSCA) in 40 CFR Part 761.
However, it’s possible that PCBs may be incidental contaminants in listed hazardous waste (e.g., solvent used to remove PCBs from transformers) or may be present in characteristically hazardous wastes. In these cases, wastes that otherwise meet a listing criterion or are characteristically hazardous are still subject to RCRA regulation regardless of PCB content.
Note that states may have more stringent regulations. Many have expanded their universe of regulated wastes to cover additional waste, such as PCBs, that aren’t defined as hazardous under the federal program.