Maine
Underground Oil Storage Tanks (UST)
The Underground Oil Storage Tanks (UST) program of the Maine Department of Environmental Protection (DEP) sits in its Bureau of Remediation and Waste Management. DEP says the program aims to protect public health and the environment, groundwater in particular, by preventing oil discharges. Its program page says there are roughly 3,000 registered USTs at approximately 2,000 underground oil storage facilities in Maine; the page gives no date for that count.
In a Phase I ESA
DEP's tank registrations are the Maine form of the state registered storage tank records that ASTM E1527-21 lists as a standard source. The general reading of a registered tank listing is on the UST / AST page. A registration says a tank exists or existed. A leak is a separate record: see Petroleum Clean Up and the Hazardous & Oil Spill System (HOSS). Three Maine details shape the search.
- Removed tanks stay in the database. DEP says its tank database includes all underground tanks registered with DEP since 1986, including tanks that have been removed. A search can therefore show tanks that are no longer in the ground.
- Some aboveground tanks are in it too. The same database includes aboveground tanks permitted by the State Fire Marshal's Office since 2005 or registered with DEP. DEP's UST page says aboveground tanks storing motor fuel that are connected to underground piping must be registered with DEP and inspected annually by a Maine certified underground tank installer or inspector, under the same rules as USTs.
- The forms show the paper a tank leaves. DEP's UST forms include a notice of a temporarily out-of-service tank, a request to return a tank to service, a Notice of Intent to Remove an Underground Oil Storage Facility, a Chapter 691 summary cover sheet for the site assessment of an underground oil storage facility, a certification of inerting or purging of a removed underground gasoline tank, and a change of ownership form, which DEP says a new owner must submit within 10 days of the transfer. For a removed tank, ask DEP whether the notice of intent and the site assessment are in its file. The forms also include a spill log, for spills of less than 10 gallons on concrete or pavement that are properly cleaned up; ask whether one was kept.
DEP lists the program's law as 38 MRSA ยง 561 et seq. and its rules as Chapter 691, Rules for Underground Oil Storage Facilities, with Chapter 692 on siting, Chapter 693 on operator training and Chapter 695 on underground hazardous substance storage facilities. DEP's staff review registration materials for the repair, upgrade, installation and removal of tanks against Chapter 691.
Where to look a site up
- DEP's TankSmart page links its free Oil Storage Tank Search, which DEP says lets anyone search its database of registered oil storage tanks and obtain registration certificates. DEP says the registration information now includes the date of the last annual inspection.
- The UST Forms and Lists page links PDF lists, three marked updated monthly (Active and Out of Service Underground Oil Storage Tanks, Registered Underground Oil Storage Tanks, and Tank Installation Date & Material), and a Non-Conforming Tanks Report, which DEP describes as tanks that cannot have oil delivered to them. DEP's file room page describes the active and out of service list as including tanks that have not been properly abandoned.
- DEP's File Room, Reports and Lists page links the tanks database as a flat text file of owner, operator, site, tank and chamber information, updated monthly in the first week of the month. DEP's GIS Maps and Other Data Files page maps the Registered Petroleum Tanks Database. This handbook did not open the lists, the file or the map.
- For the program, DEP says to call (207) 287-7688 and ask for the appropriate staff person.
Getting the file
DEP's online document portals hold scanned files for underground and aboveground storage tanks, active and out of service; the File Room, Reports and Lists page links them. Not all files have been scanned. Paper Underground Storage Tanks files can be reviewed at the file room by appointment, at (207) 287-7843; the list of files wanted can also be emailed to brwmfileroom.dep@maine.gov. See File Room, Reports and Lists for the hours and DEP's Freedom of Access route.
Sources
Maine Department of Environmental Protection pages, read October 13, 2026, no modified date shown: