The Resource Conservation and Recovery Act (RCRA) requires states to adopt and implement permit programs or other systems of prior approval to ensure that municipal solid waste landfills (MSWLFs) and non-municipal, non-hazardous waste disposal units that receive conditionally exempt small quantity generator (CESQG) hazardous waste comply with the federal revised criteria established for these disposal units. RCRA further directs the Environmental Protection Agency (EPA or the Agency) to determine whether state permit programs or other systems of prior approval are adequate to ensure compliance with the federal revised criteria. This final rule provides a flexible framework for modifications of approved programs, establishes procedures for withdrawal of approvals, and confirms the process for future program approvals so that standards that safeguard human health and the environment are maintained.