Revised On: Aug. 26th, 2026 - 04:17 pm
Owners of an underground storage tank (UST) must notify ADEQ about their UST(s) using the UST Notification Form application in myDEQ, ADEQ's online portal. myDEQ must be used to:
- Register USTs
- Inform ADEQ of any tank system modifications
- Update the status of the UST, such as temporary or permanent closure of the tank(s)
- Notify ADEQ of ownership or operator changes that occur
- Notify ADEQ of any product storage changes
UST owners or operators are required to notify ADEQ of a newly installed UST system at least 30 days before it is brought into operation. UST owners are generally required to notify ADEQ of other changes relating to an UST system within 30 days of that change.1
New Owners
When there is a transfer of UST ownership, the seller must notify ADEQ that they have transferred their interest in the UST system, including the contact information of the purchaser. The seller must also advise the purchaser of the UST notification requirements. The seller can meet these requirements by using the UST Ownership Transfer Notice form | View Forms >
After the transfer is effective, state regulation requires new owners and operators to submit a Change of Ownership Notification Form to ADEQ within 30 days1 | Visit myDEQ Portal >
To begin the transfer process, contact the UST Program | 602-771-2000 | Email >
Change of Substance
UST owners and operators must notify ADEQ and prove their equipment is compatible at least 30 days prior to switching to a fuel blend containing greater than 10% ethanol, greater than 20% biodiesel, or any blend of isobutanol. UST owners and operators should submit this notice and supporting documents using the UST Change of Substance Reporting Form | View Forms >
If ADEQ determines the information proves the equipment is compatible with the new fuel blend, the UST owner or operator must then submit an updated UST Notification Form to report the change in the stored product.
Submit UST Notification Form information in myDEQ | Visit myDEQ Portal >
1 A.R.S. § 49-1002(G) & (H), and A.A.C. R18-12-222(H)(2)
