What tanks are regulated by the Storage Tank Program?
A regulated underground storage tank (UST) is a tank and the piping that is connected to it that is used to store regulated substances. To be an UST, at least 10% of the tank must be beneath the ground surface. The following USTs are exempt: a) farm or residential UST of 1,100 gallons or less used for storing motor fuel for agricultural or non-commercial use; b) a UST used to store heating oil only for consumptive use on the premises; c) septic tanks; d) pipeline facilities, including gathering lines; e) surface impoundments, pits, ponds or lagoons; f) storm water or wastewater collection systems such as oil water separator at oil production facilities; g) flow through process tanks; h) liquid traps or associated gathering lines directly related to oil or gas production and gathering operations; i) storage tanks situated in an underground area, if the storage tank is situated upon or above the surface of the floor (vaulted); j) USTs with a capacity of 110 gallons or less; k) USTs conta
