Two NI 320 underground storage tanks in the process of being installed

An underground storage tank, also called a UST, is defined as a tank and any underground piping connected to the tank, that has at least 10 percent of its combined volume underground. Depending on what is or was stored in the UST and the USTs purpose, the UST may be regulated under Missouri's Underground and Petroleum Storage Tank Law, found in Missouri Revised Statues, sections 319.100 to 319.139, RSMo. The Underground Storage Tank Regulations are found in Code of State Regulations 10 CSR 26-2. For information about installation, inspection and compliance requirements, visit the department's Underground Storage Tank Requirements webpage.

Contamination, even from small UST releases, can threaten the health and safety of people and the environment. Tank owners and operators are responsible for cleaning up spills and releases from their tanks, which can become very expensive, very quickly. In Missouri, petroleum UST owners and operators are required to have funds set aside to pay for the cleanup and other damages that may occur from a release from their UST systems. This requirement is known as financial responsibility.

Both owners and operators of operating petroleum USTs are responsible for complying with the financial responsibility requirement, although only one party needs to obtain financial responsibility. The department requires proof of financial responsibility from all applicable owners and operators: 

  • After a release or suspected release from a UST system
  • When a new UST system is installed
  • During a site inspection

Financial Responsibility Amounts

Financial responsibility must cover cleanups and compensate third parties for bodily injury or property damage resulting from a release. The required amount of financial responsibility is typically $1 million per occurrence and $1 million annual aggregate, but there are some exceptions: 

  • Non-marketers with less than 10,000 gallons per month throughput need only obtain $500,000 per occurrence 
  • Owners of more than 100 UST systems nationwide must obtain $2 million annual aggregate coverage

Financial Responsibility Methods

The following methods may be used, either singly or in combination, to demonstrate financial responsibility. Specific requirements for each mechanism can be found in 10 CSR 26-3. Examples and required wording for each are included in the appendices to the regulations, beginning on page 5.

The following additional methods are for use by local governments:

  • Local government financial test
  • Local government bond rating test

Additional Information