Montana Underground Storage Tank Program

tank installation in progress

The goal of the Montana Underground Storage Tank (UST) Leak Prevention Program is to protect human health and the environment by preventing releases of petroleum and hazardous substances from UST systems. The release of these regulated products into the environment threatens groundwater resources and can cause explosive vapors to seep into confined spaces and occupied dwellings.

 The objectives of the UST Leak Prevention Program are to ensure that:

  • UST systems are properly constructed and designed using recognized industry standards;
  • Installations, repairs and removals are conducted and inspected by qualified, trained and licensed individuals;
  • Active USTs are properly operated and monitored for releases;
  • Upon closure, USTs are properly decommissioned and sites assessed for contamination.

Do Not Fill Report:  It is a substantial violation to fill these UST systems


Owner Change Forms:

  • State rule requires owners of UST facilities to inform DEQ of any changes to their facility (e.g., new facility name, change of owner, inactivation of tanks, financial responsibility, etc) within 30 days of the change
  •  Forms for this purpose are located at  

Information Requests:

To request information regarding an  underground storage tank facility, please click HERE  and click Submit Records Request.


EPA Proposes to Finalize its Reauthorization of Montana’s UST Program on August 15, 2019 

Summary of 2018 UST Regulations PowerPoint

  • The EPA has requested approval of the Montana Department of Environmental Quality Underground Storage Tank (UST) program. EPA has published in the federal register both a Proposed Rule and a Direct Final Rule Federal Register (FR) notice on August 15, 2019. The purpose of these FR notices is to propose and then finalize the EPA’s reauthorization of the state of Montana’s UST Program. Both FR notices can be reviewed and commented on by the public at or going to and then searching for docket EPA-R08-UST-2018-0827
    • TIMING: The Proposed Rule provides a 30-day comment period from the date of publication. Unless the EPA receives relevant adverse comment within this comment period, the rule will become effective 60-days after the publication of the Direct Final Rule. If the EPA receives any relevant adverse comments, the EPA will publish, on or before the Direct Final Rule’s effective date (60-days from publication), a notice in the FR withdrawing the Direct Final Rule and informing the public that the rule will not take effect. Subsequently, the EPA will address the public comments and republish a final authorization. 
    • BACKGROUND: Subtitle I of the Resource Conservation and Recovery Act (RCRA) of 1976, 42 U.S.C. § 6901 et seq., which amended the Solid Waste Disposal Act (SWDA), revisions were effective October 13, 2015. The implementing regulations found at 40 CFR Part 280 set minimum standards for new tanks and require owners and operators of existing tanks to upgrade, replace, or close them. The UST regulations also require owners and operators to monitor their UST systems for releases and maintain financial assurance for petroleum USTs. In accordance with 40 CFR Part 281, a state may apply for SPA any time after the promulgation of new federal rules. In 2015, the EPA published substantial revisions to the federal UST regulations. These revisions strengthened the 1988 federal UST regulations by increasing emphasis on properly operating and maintaining UST equipment, among other things. The EPA originally authorized Montana’s UST program, based on the State’s November 23, 1989 regulations, on February 1, 1996 (61 FR 3599; effective March 4, 1996). Montana submitted revisions to its UST program based on the federal EPAct regulatory revisions in an official authorization package dated November 13, 2018 and received by EPA on December 3, 2018.
  • EPA publishes compliance advisory to remind owners and operators of their compatibility regulatory requirements on allowing sales of gasoline blended with up to 15% ethanol year round.   The document is located at  
  • Montana Underground Storage Tank Rules 2018 brochure - This brochure highlights the rule changes adopted by UST in October 2018 and when these changes (walkthrough inspections, fuel compatibility, release detection requirements, out-of-tank detection, testing requirements, and major provisions adopted by Montana UST Program) will need to be implemented at your facility, along with leak reporting and resources and forms links and information.
  • UST Monthly and Annual Walkthrough Inspection Form - Final.  Starting in October 2021, owner or operators will be required to do monthly and annual walkthrough inspections of their underground storage tank systems to make sure your equipment is working properly and catch problems early. The form showing you what you will be required to inspect is now available.  The form is now finalized, so you can start doing your inspections. This inspection is required by the EPA rule revision of 2015
  • EPA publishes new publication on corrosion study of steel and steel components of USTs storing diesel fuel.  For UST owners and operators who store diesel fuel, the Montana DEQ Underground Storage Tank Program highly recommends reading the EPA notice using the link below. 


Other Information: