By law, the parties responsible for the use, transportation, storage, and disposal of hazardous substances and oil are liable for costs. This liability applies to the cost of containment, cleanup, and damages resulting from a release related to their own activities. EPA's goal is to identify the responsible parties and ensure that they pay these costs.
https://www.epa.gov/emergency-response/who-pays#:~:text=By%20law%2C%20the%20parties%20responsible,related%20to%20their%20own%20activities.