Underground Storage Tank (UST) Program

The purpose of the Underground Storage Tank (UST) program is to protect public health and the environment from UST spills, leaks, emissions, discharges, escapes, leaches or disposals (also known as releases) of petroleum and other regulated hazardous substances into groundwater, surface water or soils.

The program regulates the majority of USTs in Arizona with the exception of those on Indian Country. Nearly all USTs at these sites contain petroleum. These sites include marketers who sell gasoline to the public (such as service stations and convenience stores) and non-marketers who use tanks solely for their own needs (such as fleet service operators and local governments). 

Do you know if your UST is regulated?  | Learn more about regulated USTs >

Program Components

Leak Prevention

The UST program conducts inspections at UST facilities, focusing on verifying leak detection equipment, spill containment, overfill protection and operator training. UST inspectors are available to help UST owners and operators understand the importance of system testing and maintenance activities that prevent releases from their UST systems. The program provides compliance assistance to UST owners and operators about requirements for confirming a suspected release and for the initial response to a confirmed release | Learn More about Leaking USTs >

Corrective Action

The activities necessary to investigate, analyze and conduct cleanup activities are called “corrective actions” (Arizona Revised Statutes § 49-1005). Generally, releases from regulated USTs are overseen by ADEQ's UST Program. The UST Program provides compliance assistance and regulatory oversight for UST owners and operators who have had a release from their UST system. The program also assists property owners who voluntarily undertake corrective actions (these activities are often related to property re-development).

In addition to regulatory and technical support, UST owners, operators and property owners may qualify for financial assistance through either the State Lead Program or the Preapproval Program. 

Learn More about the Preapproval Program >
Learn More About State Lead Corrective Action Program >


If the UST owner and operator fail to conduct adequate corrective action for their UST release within time frames required by federal and state regulations, the UST Program may initiate enforcement actions against them | Learn More About UST Compliance Assistance > 

Not sure what an Underground Storage Tank (UST) is? | Learn More About USTs >