UST / LUST Glossary | Region 10 | US EPA

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UST / LUST Glossary

This program is managed by

the Groundwater Unit of the Office of Compliance and Enforcement.

Definitions on this page:
Change-In-Service Modifications

Modifications to an UST system such that a non-regulated material will be stored in a tank that held a petroleum product or hazardous substance. If such modifications are to be made, owner/operators must follow federal UST regulation 40 CFR 280.71(d) by emptying and cleaning the tank by removing all liquid and accumulated sludge and by conducting a site assessment.

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Currently in Use

A tank that contains a regulated substance and is being used to dispense product.

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Hazardous Substance

As defined in section 101(14) of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of 1980, but not including any substance regulated as a hazardous waste under subtitle C), “hazardous substance” means the following:

The term does not include petroleum, including crude oil or any fraction thereof which is not otherwise specifically listed or designated as a hazardous substance under subparagraphs (A) through (F) of this paragraph, and the term does not include natural gas, natural gas liquids, liquefied natural gas, or synthetic gas usable for fuel (or mixtures of natural gas and such synthetic gas).”

For a list of hazardous substances regulated under Subtitle I of RCRA for USTs, visit OUST. For more information on hazardous substance USTs, visit OUST’s site on hazardous substance UST requirements.

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Indian Lands

Any land defined below that has underground storage tank systems are regulated by EPA:

Indian Lands / Indian Country: Title 18, U.S. Code, section 1151, identifies three areas as Indian country.

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Indian Reservation: An Indian reservation is an area of land "reserved" for Indian use, usually under the terms of a formal treaty. Most reservations today also have non-Indian residents and non-Indian landowners.

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Trust Lands: Lands that are held in trust by the United States government for Indian tribes and individuals. No law permits a tribe to sell its land, although an individual Indian may do so with the approval of the Secretary of the Interior.

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Tribal Lands: Lands that are either held in trust by the Bureau of Indian Affairs (BIA) or other lands under the direct ownership of a Tribe. Most tribal lands are in trust status and within a reservation, but these lands also can be outside of a reservation.

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Fee patent: Indians who wish to be given ownership of their trust land can request the Secretary of the Interior (BIA) to approve a "fee patent" for the land. If approved, the "fee patent" is actually issued by the Bureau of Land Management, removing the land from trust status.

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Fee simple land: Fee simple land is owned outright by an entity, such as a corporation, an individual or an Indian tribe and is subject to property taxes. Ownership can be Indian or non-Indian and can even exist within a reservation. Fee simple land carries no restrictions by the BIA for its use or sale.

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Regulated Substance

According to Subpart A of 40 CFR 280.10, a “regulated substance” means:

(a) any substance defined in 101(14) of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) of 1980 (but not including any substance regulated as a hazardous waste under subtitle C), and

(b) Petroleum, including crude oil or any fraction thereof that is liquid at standard conditions of temperature and pressure (60 degrees Fahrenheit and 14.7 pounds per square inch absolute). The term “regulated substance” includes but is not limited to petroleum and petroleum-based substances comprised of a complex blend of hydrocarbons derived from crude oil through processes of separation, conversion, upgrading, and finishing, such as motor fuels, jet fuels, distillate fuel oils, residual fuel oils, lubricants, petroleum solvents, and used oils.”

Substances in section (a) above are “hazardous substances”.

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Temporarily Out of Use

A tank that is empty or contains product and/or abandoned but not currently in use. (Note: There are release detection, corrosion protection and financial responsibility requirements that may apply to these tanks.) According to federal UST regulation 40 CFR 280.70,

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UST systems that are federally regulated

According to Section 9001 of RCRA’s Subtitle I, federally regulated UST systems are defined as “any one or combination of tanks (including underground pipes connected thereto) which is used to contain an accumulation of regulated substances, and the volume of which (including the volume of the underground pipes connected thereto) is 10 percent or more beneath the surface of the ground.” They do NOT include:

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URL: http://yosemite.epa.gov/R10/WATER.NSF/UST/UST+Glossary

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