Waste is regulated at the federal and state levels. In general, state regulations supersede federal regulations in that they may be more stringent. The following resources provide state-based information about solid waste disposal.
State-based EPA Resources
Looking for your state's regulations regarding animal disposal?
The Cornell Waste Management Institute's U.S. Butcher Waste and Mortality Disposal Laws resource may help you find the answers you need.
Environmental Compliance Assistance Platform (EnvCAP) – this is a "clearing house" of industry-specific resources to help members of those industries comply with regulations.
Veterinary Compliance Assistance (VetCA) – a subsection of EnvCAP with resources relevant to veterinary practices
2015 American Veterinary Medical Association