An automatic tank gauge, or ATG, is an electronic system that watches an underground fuel tank around the clock. It reports how much fuel is inside and warns you early if the tank is leaking.
Inside the tank sits a probe that floats on the fuel and senses the level continuously. It feeds a console in the store or office, so anyone can see how many gallons are in each tank without dropping a measuring stick down the fill pipe by hand.
Its bigger job is catching leaks. The ATG runs quiet tests, often overnight when no fuel is moving, to see whether the level drops on its own. A leak from an underground tank can poison soil and groundwater and bring heavy fines, so the law in most places requires this kind of monitoring.
For an operator the ATG is both a safety device and a money tool. The same readings that prove the tank is sound also let you reconcile, meaning compare the fuel the tank says you have against what your sales say you sold. A steady gap points to a leak, theft, or a bad meter while it is still small.
In useThe ATG flagged a slow drop overnight on the premium tank, so the operator pulled it from service and called for a leak test before it became a spill.
Where the word comes from
The name is plain description: a gauge that measures the tank automatically, kept on at all times instead of read by hand.
See also Underground storage tank (UST), Wet stock, Reconciliation