What are the Portland Fire Department Oil Tank Permits?
Have you been on PortlandMaps.com and noticed that some houses have a permit for an ‘underground storage tank’? Those permits were for the installation of Heating Oil Tanks. If you’re a new real estate agent you might notice that while many houses have oil tanks only some of them have permits. Only houses in a certain area got a UST permit. Not every house with a tank in this ‘Permit Zone’ (see below) as a permit, for one reason or another.
Which houses have permits for ‘underground storage tanks’?
The permits shown on PortlandMaps are by the Portland Fire Department from 1936-1990. And only for homes that were within the city limits of Portland-proper at the time the house was built. Installation of heating oil tanks, both above ground and underground, as well as replacement oil burning furnaces, and underground gasoline tanks all got permits.
Look at the below map which shows Portland city limits annexations by decade. The ‘Permit Zone’ I have outlined shows where you might expect to find a permit. You will never find a permit outside the permit zone. However a house within the zone can still have one (or more) tanks and no permits.
How to read the PortlandMaps.com permit
There are a few styles of permits as they evolved over the years. The permits usually show: a date, a furnace model, a selection field for where a heating oil tank is, and sometimes a place to indicate the size of the tank.
Read our article, the history of heating oil tanks in Portland, to better understand oil tanks in general. The presence of a permit in the underground storage tank field doesn’t necessarily mean there is a tank present. The permit could be for a replacement furnace. However it might instead signify a replacement tank, meaning the house might still have one or more underground storage tanks. If the age on the permit is the same as the year the house was constructed (or a year before) then you won’t see the ‘oil supply trench’ like on our ‘signs of oil tanks‘ page.
On later permits there is a area to indicate the size in gallons of the tank along with the location. Tanks marked ‘exposed’ are classified as above-ground tanks and are not subject to the same soil sample regulations from the DEQ. ‘Integral‘ tanks are similar to space-heaters, they hold 5 gallons of diesel fuel and sit inside the home. 
The permits listed on portlandmaps.com are created by the Oregon Environmental Service.
Underground tanks are much more likely in homes that used oil heat in the past, so get an Oil Tank Search if there is an oil tank permit for the home you or your clients are looking to buy.
