When are you supposed to replace gas station-sized double wall tanks?
I work for a certain state in the east regulating USTs. Totally of record, they don’t need to be replaced as long as neither wall is damaged. Steel tanks need cathodic protection – either galvanic anodes (which are at ached to the tanks) or impressed current through anodes that are buried above the tank field. You’ll almost assuredly need to test your cathodic protection every 3 years, it’s the law in this state. Double wall tanks can be steel inner, Fiberglass reinforced plastic (FRP) or both. They obviously don’t need CP. As far as replacing them goes there is no set time limit like I said as long as both walls are sound. The price of removal and new installation varies greatly by the size of the tank(s) and how many. I would guess starting around $30,000 – to well over $100,000.
