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. Just discovered a tank on your property? Review the Discovered Tanks requirements.

Please visit Permitting and Operator Assistance for owner and operator information, facility summary sheets, UST forms, permitting, and licensing information. Resources hosts a range of guidance and mapping material, technical resources for licensees, and the Laws and Regulations pertaining to Underground Storage Tanks. Can't find the data you are looking for? Use our Records Request button to submit a records request. 

Objectives

• 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

• Maintain an updated Do Not Fill Report: it is a substantial violation to fill these UST systems.

Underground Storage Tank Program | Rule adoption notice regarding MAR Notice 2025-205.2 | Public Notice

• December 19 2025

The Department of Environmental Quality (DEQ) has adopted amendments to Title 17, chapter 56 of the Administrative Rules of Montana, pertaining to the Montana Underground Storage Tank Installer and Inspector Licensing and Permitting Act at Title 75, chapter 11, part 1, MCA. DEQ has amended ARM 17.56.1001 and ARM 17.56.1404 as proposed in MAR Notice 2025-205.1: Issue 16 on August 22, 2025. No comments or testimony were received.

The effective date of these changes will be December 20, 2025.

Associated Materials:

• MAR Notice No. 2025-205.2 within MAR Issue 24   MAR Notice 2025-205.2

Send Questions/Comments to:

• DEQUSTPROGRAM@MT.GOV

Or call (406) 444-5300