Underground Storage Tank Clean-Up
Residential Home Heating Oil Tanks
The installation and use of residential home heating oil tanks serving four or fewer units are not regulated by DEEP. However, any contamination resulting from these tanks, including the clean-up of such contamination is regulated. There is no DEEP funding for residential home heating oil tank removal or replacement, or clean-up with a leaking tank. Any costs associated with maintenance and eventual removal of residential heating oil tanks, including costs for remediation, should be considered when purchasing residential real estate. A permitted spill cleanup contactor must perform the necessary remedial actions.
Guidance for Residential Home Heating Oil Tank Leaks
Other Underground Storage Tanks
Non-residential underground storage tanks (“UST”), including those for oil, petroleum and chemical liquids, are regulated by DEEP. Releases from such tanks must be reported to DEEP and remediation must be performed pursuant Section 22-449(d)-1(i) and 22a-449(d)-106 of the Underground Storage Tank Regulations. A permitted spill cleanup contactor must perform the necessary remedial actions. UST owners and operators are responsible for maintenance, testing, and eventual removal of their USTs and must demonstrate financial responsibility for releases from their USTs. Documentation, including the forms and in some cases reports, of the investigation and cleanup actions taken for releases from regulated UST systems should be submitted to DEEP.
Releases requiring cleanup pursuant Section 22a-449(d)-106, also require information on the investigation and cleanup of the releases to be submitted on the forms prescribed by the Commissioner. The forms prescribed by the Commissioner include:
- Initial site characterization form, as required by 22a-449(d)-106(f)(2);
- NAPL action form, as required by 22a-449(d)-106(g)(3);
- Completion-of-investigation form, as required by 22a-449(d)-106(h)(2)(B);
- Remedial action plan form, as required by 22a-449(d)-106(i)(1)(B);
- Completion of remedial action form, as required by 22a-449(d)-106(i)(3)(B);
- Monitoring and progress status form, as required by 22a-449(d)-106(i)(4)(B), 22a-449(d)-106(k)(4)(B) and 22a-449(d)-106(l); and
- Non-compliance form, as required by 22a-449(d)-106(h)(1).
The forms are compiled into one “form” where specific Parts are required based on the form type being submitted. The instructions for the form provide more details on how the form should be filled out and what should be included with the form.
For releases discovered on or after May 7, 2025, to comply with the requirements 22a-449(d)-106, the prescribed forms are required.
For releases discovered prior to May 7, 2025, that are not currently proceeding in compliance with the UST regulations effective July 28, 1994, to comply with the requirements 22a-449(d)-106, the prescribed forms are required.
For release response already underway as of May 7, 2025, and proceeding in compliance with the UST regulations effective July 28, 1994, the UST Facility’s owner and operator can either proceed in accordance with those regulatory requirements effective July 28, 1994, or submit cleanup progress on the prescribe forms. In either case, compliance must be documented by submittal of a Monitoring and Progress Status form.
Please note for release regulated under Section 22a-449(d)-106, fees will accrue if investigation and corrective actions are not completed, and if post-remedial groundwater monitoring does not demonstrate compliance within timeframes specified in the regulations. These fees will accrue for releases reported after May 7, 2025, and also for releases reported prior to May 7, 2025. To prevent the accrual of a fee please complete the required investigation and corrective actions within one year of the discovery date and demonstrate cleanup compliance within two years of the date of the Completion of Remedial Action form submittal. For releases reported/discovered prior to May 7, 2025, compliance must be demonstrated by May 7, 2027, to prevent accrual fees. Compliance must be documented by submittal of a Monitoring and Progress Status Form.
The prescribed form must be signed by the appropriate parties and mailed with wet signatures to the DEEP:
Department of Energy and Environmental Protection
Bureau of Materials Management and Compliance Assurance
Emergency Response and Spill Prevention Division
Corrective Action Unit
79 Elm Street
Hartford, CT 06106-5127
Flow Chart of forms for required by 22a-449(d)-106
Form for Leaking Underground Storage Tank Systems
Instructions for Form for Leaking Underground Storage Tank Systems
Emergency Response and Spill Prevention Division's Complaint Intake System
Sampling and Analytical Methods for Underground Storage Tank Closure
Remediation Standard Regulations
General Site Clean-up Information
DEEP Document Online Search Portal
The UST Petroleum Clean-up Program has ended on June 23, 2025. All appropriated amounts were transferred to the general fund and all pending applications are deemed cancelled. See Sections 165 and 166 in the State Budget For The Biennium Ending June 30, 2027
List of UST Petroleum Clean-up Program Sites
For further information on UST cleanup please contact the DEEP Corrective Action Unit at DEEP.LeakingUST@ct.gov or (860-424-3376), or write to:
Department of Energy and Environmental Protection
Bureau of Materials Management and Compliance Assurance
Emergency Response and Spill Prevention Division
DEEP Corrective Action Unit
79 Elm Street
Hartford, CT 06106-5127
Content last updated June 27, 2025