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Connecticut

Residential Home Heating Oil Tanks

Agency Department of Energy and Environmental Protection

The Department of Energy and Environmental Protection (DEEP) keeps a group of pages on residential home heating oil tanks beside its emergency response and spill pages. Its FAQ calls an underground tank residential when the heating oil it holds heats four or fewer residential units. DEEP says a home tank may be in the basement, outdoors above ground near the house, or buried close to it.

In a Phase I ESA

ASTM E1527-21 does not name heating oil tank records among its standard record sources. DEEP's September 2026 pages distinguish residential from nonresidential underground tanks by the number of units heated; notification requirements also depend on capacity. Cleanup paperwork depends on whether the release is covered by the RBCRs and who caused it.

  • Residential underground tanks are outside the tank program. DEEP says it does not regulate residential heating oil underground tanks, which the statute defines by the limit of four units served. Do not rely on Underground Storage Tanks registrations to identify these tanks; ask the owner about past and present tanks and look for fill and vent pipes on the site visit.
  • Five units or more: a regulated tank. DEEP counts an underground tank that heats five or more residential units as nonresidential even though people live in the building, and regulates it under RCSA 22a-449(d)-1; a tank that also fuels an emergency generator is regulated differently. For a sale of such a property, DEEP's page lists giving the buyer all information about the tank, such as its age, construction and location, at least 15 days before closing. For tanks of 2,100 gallons or more, that includes a copy of the annual notification that CGS section 22a-449(e) requires, and DEEP says unprotected steel tanks in that size range are past their life expectancy and must be removed. On an apartment property, ask for the disclosure.
  • No removal deadline for a residential underground tank. DEEP's FAQ says it sets none, but a leaking residential underground tank must be emptied and taken out promptly. DEEP discourages closing a tank in place unless it cannot be reached (under a deck, patio or addition, for example) or digging would put a foundation at risk, and asks for a soil sample under the tank before it is filled with sand or concrete. Ask for that result where a tank was closed in place. DEEP's maintenance page, content last updated October 2021, says a 275 gallon tank buried underground should come out as soon as possible, since tanks of that size are built for use above ground.
  • Leaks are reported and cleaned up. DEEP asks that a leak from any tank or its piping be reported to its Emergency Response and Spill Prevention Division at 866-337-7745. It says the property owner, or the party that caused the pollution, is responsible for the cleanup, including on neighboring land. The UST Clean-Up page notes that DEEP offers no funding for these tanks.
  • The release rules reach home tanks. DEEP's leak guidance, content last updated September 2026, says releases of residential heating fuel from tank systems serving four or fewer units that are discovered after March 1, 2026 come under the Release Based Cleanup Regulations (RBCRs), with time limits for immediate and remedial actions. See Release-Based Cleanup Program.

What the record shows

DEEP's September 2026 leak guidance separates closure reports for releases covered by the RBCRs according to who caused the release. It also describes a letter report for releases that occurred before the RBCRs.

  • Before the RBCRs. DEEP asks the contractor for a letter report on the tank removal and the digging out of contaminated soil, with photos, a sketch marking every sample location and all lab results, and for copies to go to DEEP's Emergency Response Unit and the local Fire Marshal.
  • Under the RBCRs, caused by the homeowner or occupant. The release remediation closure report should show that the immediate actions required under section 22a-134tt-5 were taken and that impacted soil was removed "to the maximum extent prudent", and should identify the nature and extent of the impacted soil that stayed. Read that part of the report: it is where the report should say what impacted soil was left in the ground.
  • Under the RBCRs, caused by someone else, such as a fuel provider. The closure report should show that the soil cleanup meets the RBCRs.

Either RBCR report should also say whether groundwater was affected; if it was, a Licensed Environmental Professional (LEP) must verify the groundwater cleanup under section 22a-134tt-10. A Permitted Environmental Professional (PEP) certifies that the work is complete, or an LEP verifies it, and the reports go to DEEP through REACT.

On sampling, DEEP asks for separate samples from the floor and each wall of the excavation, a water sample where groundwater stands in it, and testing by a lab certified in Connecticut for Extractable Total Petroleum Hydrocarbons (ETPH), with more digging where ETPH is above 500 ppm. It says soil venting can treat staining that cannot be dug out, such as under a footing. If a report mentions a venting system or staining left under a footing or floor, ask what remains. For a residential underground tank removal, DEEP's FAQ says a soil sample from under the tank and piping must be tested for ETPH, suggests photos and a short letter report from the contractor, and says buyers usually want that proof.

Where to look a site up

DEEP's FAQ lists where records of a residential underground tank removal may be found, the likeliest first:

For questions, the FAQ gives the Corrective Action Unit at DEEP.leakingust@ct.gov or 860-424-3376, the Emergency Response and Spill Prevention Division at 860-424-3024 (press 2), and the Storage Tank and PCB Enforcement Unit at 860-424-3374.

Getting the file

The pages read do not say that a report on a home tank removed without a leak goes to DEEP, so ask the owner and the local Fire Marshal for it. For a leak, DEEP's files that are not online are at the Environmental Quality Records Center, and DEEP takes requests under the Freedom of Information Act.

Sources

Department of Energy and Environmental Protection pages, read October 17, 2026:

Maintained by Barrow. General reference only, not legal or professional advice. Barrow is not affiliated with any government agency, and neither Barrow nor the information as presented here is endorsed by any state or government agency. See how Barrow drafts the report