Montana Department of Environmental Quality About Us Permitting & Operator Assistance Public Participation

Petroleum Tank Cleanup

Program Overview

The goal of the Petroleum Tank Cleanup Section is to protect human health and the environment from petroleum and hazardous substance releases from both underground and above ground storage tank systems.

  • Directs and oversees reporting, investigation, cleanup, and resolution of petroleum releases.
  • Is the technical resource for tank owners and operators (O/O), consultants, local government officials, and the public to help respond to questions or concerns about the cleanup of petroleum releases.
  • Approves the cleanup efforts of the facility O/O, assesses the potential threat to human health and the environment and provides technical assistance with corrective action.
  • Works with O/O and their identified funding source (often the PTRCB) which provides financial assistance for eligible corrective action remediation.
  • Administers other funding sources:
    o Leaking Underground Storage Tank (LUST) Trust Fund Program 
    o Petroleum Brownfields Program
    o Special Legislative Funding

HOTLINE for Reporting Leaks

Monday through Friday 8:00 a.m. to 5:00 p.m.
call 1-800-457-0568

After hours and holidays call 1-406-324-4777

NOTE: You must report to a live person.

Leaving a message does not constitute a report.


Petroleum Tank Cleanup Contacts

Main Number: (406) 444-6444


Petroleum Tank Cleanup Staff (PDF)


Helena PTCS Office
(406) 444-6444
1225 Cedar St.
Helena, MT 59601

Billings PTCS Office
(406) 444-6444
Airport Business Park IP-9
1371 Rimtop Dr.
Billings, MT 59105-9702

Bozeman PTCS Office
(406) 444-6444
Martel Building Ste 3B, 220 West Lamme St.
Bozeman, MT 59715

Kalispell PTCS Office
(406) 444-6444
655 Timberwolf Pkwy
Kalispell, MT 59901

Risk Based Corrective Action Guidance (RBCA)

Remedial Investigation Guidance
Remedial Alternatives Analysis Guidance
Cleanup Guidance
Groundwater Monitoring Work Plan and Report Guidance
Release Closure Plan (PDF not fillable)
Release Closure Plan (Excel)
Petroleum Brownfields Guidance

draft Montana Quality Assurance Plan for Investigation of Underground Storage Tank Releases-Draft

Electronic Submittals:

Technical Guidance Documents:

The following are links to example field sampling forms that may be of assistance.

APH VI Calculator

*The Air-Phase Petroleum Hydrocarbon Vapor Intrusion (APH VI) Screening Level Calculator is designed as a simple screening tool to determine if vapor intrusion exceeds generic risked-based screening levels at sites with only  petroleum contamination. This calculator is  not meant to be used with solvent sites or mixed waste sites containing a combination of petroleum and other sources. The results from this calculator should be considered one of the multiple lines of evidence in your vapor intrusion investigation.  Below you will find the APH VI Screening Level Calculator as well as the VI APH Calculator Discussion that explains how to use the calculator and the general assumptions used for site-specific vapor intrusion risk assessment/analysis (also found on  DEQ SRS’s FAQs website).

APH VI Calculator

Landfarming Soils: Contact Solid Waste Section for permitting and monitoring requirements at 406-444-5300.

The work plans on this table have been Submitted for Local Government Review or subsequently Approved by DEQ since January 1, 2014. They are organized chronologically by expected completion dates, and entries will be removed following completion. More information regarding implementation and scope of work is available at the links provided in the Work Plan column. If you have further questions or concerns, please contact the associated DEQ Project Manager, either at the linked email address or by calling: (406) 444-6444

Last Updated: February 1, 2023




Project Manager

Work Plan


Completion Date


Great Falls Subaru

Great Falls Chris Herman 34642 Local Gov Review 02/16/2023

Former Stockton Oil Company Bulk Plant

Billings Jay Shearer 34641 Local Gov Review 02/14/2023

MDOT Lost Trail Site

Darby Reed Miner 34651 Local Gov Review 02/10/2023

Former Elmer's Restaurant

Great Falls Donnie McCurry 34607 Local Gov Review 02/08/2023

Vaughn Truck Stop

Vaughn Chris Herman 34522 Local Gov Review 02/07/2023

Holiday Station Store 59

Great Falls Chris Herman 34628 Local Gov Review 02/03/2023

LUST Site List

Click the links below to open, save, or print the Montana Leaking Underground Storage Tank (LUST) list of all sites. 
If you have questions or need further information, please call the program support specialist at 406-444-6444 or submit a records request through the DEQ Public Records Center.

These lists are current through January 2022.

The Spatial (Lat\Long) data is no longer accessible on the LUST List.

The data available from these lists is summary information and should be used for general purposes only. Street addresses are provided as a courtesy and should be verified by the user. 

 February 27, 2023  



Register Here



Petroleum Cleanup Section FAQ

A. Program overview and applicable laws and rules
B. Cleanup Process-Confirmation, Investigation, Release Cleanup, Long-Term Monitoring
C. Resolving or Closing a Petroleum Tank Release

 Program overview and applicable laws and rules

A1. I have a petroleum release from a tank; what do I do now? 

If the petroleum release is from a tank system, either an underground storage tank or an above-ground storage tank, you need to call one of the following numbers within 24-hours of detecting the leak: 

  • 1-800-457-0568 From 8:00 AM – 5:00 PM, Monday through Friday (DEQ)
  • 1-406-324-4777 After-hours and holidays (Disaster and Emergency Services)

If your petroleum release is from a tanker truck that is not connected to a UST or AST system, or any other source, call the DEQ Enforcement Division at (406) 444-0379. 

A2. Who is responsible for notifying the state of a petroleum release from a tank?

An owner/operator, any person who installs or removes an UST, or who performs subsurface investigations for the presence of regulated substances, and any person who performs a tank tightness or line tightness test must notify DEQ or the Disaster and Emergency Services officer available at the phone numbers listed in the response to A1 above. 

A3. What are the most common risks to human health, safety, and the environment at a typical petroleum tank release site? 

For a release regulated under the Montana Underground Storage Tank Act (75-11 Chapter 5, MCA) or the Petroleum Storage Tank statute (75-11 Chapter 3, MCA), the most common risks at petroleum release sites are from: 

  • People potentially drinking contaminated water (either from a contaminated aquifer or permeation of a water pipe);
  • Human exposure to vapors migrating into buildings; and
  • Construction workers contacting petroleum-contaminated soil during excavation work. 

Other risks can include direct human contact with contaminated surface or subsurface soil and contaminated surface water (rivers and lakes) which may impact humans or the environment. For more information on potential risk, select the “Risk Assessment/Analysis” topic at

Cleanup Process-Confirmation, Investigation, Release Cleanup, Long-Term Monitoring

 B1. How do I hire an environmental consultant?

The Petroleum Tank Cleanup section maintains a list of environmental consultants who you can hire to assist you with your petroleum tank release. Please refer to the following webpage for names of consulting firms, phone numbers, and advice for hiring a consultant. Consultant List .

B2. Is there any financial assistance available?

Remedial efforts at petroleum tank releases that have been deemed eligible for reimbursement from the Petroleum Storage Tank Cleanup Fund are reimbursable. For more information, please visit the Petroleum Tank Release Compensation Board website.

The Department of Natural Resources (DNRC) works with DEQ in granting cleanup funds to eligible sites with environmental issues and compelling benefits to the impacted communities. The specific grant program is called Reclamation and Development Grants program and for more information on the grants available through DNRC, please visit their website at: Reclamation and Development Grants Program

DEQ and the US Environmental Protection Agency oversee Brownfields funding for investigation and cleanup to eligible petroleum release sites. For more information regarding the Montana DEQ Brownfields funding or a petroleum release’s potential eligibility for Brownfields, please visit: Montana Brownfields Program.

Resolving or Closing a Petroleum Tank Release

C1. What is required to close a petroleum release regulated by the Montana Underground Storage Tank Act (75-11 Chapter 5, MCA) or the Petroleum Storage Tank statute (75-11 Chapter 3, MCA)?

The term close or closure is synonymous with resolving the release in accordance with Administrative Rules of Montana (ARM 17.56.607(4)).

The technical guidance document for petroleum release closure provides a comprehensive look at closure requirements. Please use the following link to find the Site Closure Evaluation, Including Petroleum Mixing Zones technical guidance document: Petroleum Release Closure Categorization

C2. Does DEQ-7 contain all the chemicals found in gasoline and diesel?

No. Gasoline, diesel, and other refined petroleum products are made up of hundreds of chemicals. Only about a dozen or so of these chemicals have standards listed in DEQ-7. DEQ created and periodically updates its guidance document called Montana Tier 1 Risk Based Corrective Action Guidance for Petroleum Releases (also referred to as RBCA). In its RBCA document, DEQ has defined risk-based screening levels (RBSL) for soil and groundwater at petroleum release sites. For specific chemicals of concern, both DEQ-7 chemicals and those with calculated risk-based screening levels (RBSL), refer to the RBCA Document.

C3. What cleanup levels do petroleum release regulated by the Montana Underground Storage Tank Act (75-11 Chapter 5, MCA) or the Petroleum Storage Tank statute (75-11 Chapter 3, MCA) have to meet?

The DEQ has developed a method published in Montana Tier 1 Risk-based Corrective Action Guidance for Petroleum Releases (RBCA) to address petroleum chemicals not listed in DEQ-7. RBCA identifies concentrations of petroleum chemicals called “risk-based screening levels” or “RBSL” to evaluate risks posed to human health and the environment. Petroleum releases cleaned up to levels below RBSL are determined to be protective of human health and the environment. RBCA has been incorporated by reference into Montana tank rules addressing site closure found at ARM 17.56.608.

C4. Can a petroleum tank release regulated by the Montana Underground Storage Tank Act (75-11 Chapter 5, MCA) or the Petroleum Storage Tank statute (75-11 Chapter 3, MCA) be closed when groundwater exceeds DEQ-7 standards or RBSL, and the contamination is not migrating beyond the property boundaries?

Maybe; all groundwater is state water even that located only under the facility that is the source of the release. DEQ considers all exposure routes and all receptors before making a determination if a petroleum release is ready for closure. If no receptor is exposed to groundwater contaminated by residual petroleum fractions that have only an RBSL, the petroleum tank release could close. However, if a specific chemical listed in DEQ-7 exceeds water quality standards (such as benzene), the release will remain open until the contamination is less than the standard or until petroleum mixing zone has been approved.

C5. What is a petroleum mixing zone closure?

A petroleum mixing zone closure is a category that a petroleum tank releases regulated by the Montana Underground Storage Tank Act (75-11 Chapter 5, MCA) or the Petroleum Storage Tank statute (75-11 Chapter 3, MCA) can be resolved or closed in situations where the groundwater continues to have petroleum chemicals that exceed DEQ-7 water quality standards. A petroleum mixing zone may be granted if the owner/operator demonstrates that the release has been cleaned up to the maximum extent practicable, the groundwater contamination plume is decreasing, and there is no other risk to receptors. A petroleum mixing zone closure will allow a petroleum tank release to be closed that has a groundwater plume that exceeds water quality standards.

The Petroleum Tank Cleanup uses a guidance document to explain a petroleum mixing zone closure and the requirements needed for a petroleum tank release to be considered for such a closure. Please see the Site Closure Evaluation, Including Petroleum Mixing Zones technical guidance document for a full description: Petroleum Release Closure Categorization.

C6. What are the cleanup levels for soil?

DEQ does not have specific soil standards for petroleum contamination but has developed risk-based screening levels (RBSLs) for soil to evaluate risk to human health and the environment. Soil RBSLs are conservatively calculated to represent concentrations of the various chemicals that should not cause unacceptable risks to human health through direct contact (ingestion, inhalation, and dermal contact) and will not leach into groundwater above DEQ-7 standards or groundwater RBSLs anywhere in Montana. Soil RBSLs are available for surface soil (less than two feet deep) and deeper soils and for both residential and commercial purposes. Soil RBSLs can be used as default cleanup levels for soil. DEQ may approve other methods to evaluate risks to human health, safety, and the environment.


*Under Construction

Petroleum Tank Release Compensation Board Forms and Worksheets
The Certificate of Financial Responsibility below is required to be on file at your facility or place of business. Your compliance inspector is required to inspect it for proper record keeping.

Enforcement Spill Report
**If there is an emergency, please dial 911 to alert local services, then fill out our spill/complaint form or call DEQ Enforcement staff at (406) 444-0379.

DEQ UST Montana Certificate of Financial Responsibility Form
Financial Data Request Form for Individuals
Financial Data Request Form for Businesses

Work Plan and Report Templates:


Data Validation Guidelines

Data Validation Summary Form

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