State file — AZ
Underground storage tanks in Arizona
10,121 registered facilities · 6,023 tanks in service · 9,330 leak records · 469 open cleanup cases (EPA UST Finder snapshot, 2018–2021 state data).
Arizona runs 8.6 tanks in service per 10,000 residents (population 7,031,568). 8,663 of its 9,330 reported releases have reached No Further Action. The regulator of record is the ADEQ UST Program, which holds the live registration and case files.
Check any Arizona address
Free screening of every registered tank and reported leak within a mile of any address.
Screen an addressBy county
| County | Facilities | Tanks in service | Leak records | Open cases |
|---|---|---|---|---|
| Apache County | 249 | 137 | 176 | 17 |
| Cochise County | 337 | 144 | 299 | 15 |
| Coconino County | 486 | 290 | 492 | 39 |
| Gila County | 208 | 94 | 197 | 4 |
| Graham County | 107 | 37 | 71 | 4 |
| Greenlee County | 38 | 11 | 42 | 5 |
| La Paz County | 141 | 66 | 143 | 27 |
| Maricopa County | 4,903 | 3,082 | 4,557 | 133 |
| Mohave County | 448 | 336 | 431 | 19 |
| Navajo County | 381 | 212 | 383 | 69 |
| Pima County | 1,514 | 794 | 1,346 | 44 |
| Pinal County | 487 | 301 | 451 | 22 |
| Santa Cruz County | 82 | 55 | 66 | 6 |
| Yavapai County | 406 | 261 | 329 | 35 |
| Yuma County | 334 | 203 | 347 | 30 |
Frequently asked questions
How many underground storage tanks are in Arizona?
The EPA UST Finder snapshot lists 10,121 registered UST facilities in Arizona, with 6,023 tanks in service and 23,841 closed or removed tanks across 15 countys.
How many tank leaks have been reported in Arizona?
9,330 releases are on record statewide. 8,663 (93%) were closed with No Further Action; 469 cleanup cases remained open in the snapshot.
Which Arizona county has the most underground storage tanks?
By facility count: Maricopa (4,903), Pima (1,514), Pinal (487), Coconino (486), Mohave (448). Use the county pages for tank and leak detail, or screen any specific address free at https://tankcheckusa.site/.