UST Check → counties → Colorado → Boulder
Underground storage tanks & leak sites in Boulder County, CO
Every figure below is from EPA UST Finder — the EPA-compiled national registry of state-reported underground storage tanks — county aggregates as published by EPA.
417registered tank facilities
273open tanks
887closed tanks
368leak incidents on record
18cleanups still open
18 leak cleanups in
Boulder County are still open — the state has not closed the case.
An open cleanup near a property you're buying or lending on is a findable, checkable fact: it appears in a
per-address screen with distance and the registry record.
Largest registered facilities
By open-tank count, from the facility-level registry. Every fact is attributed to the EPA record (linked ID); something wrong — use the correction path in the footer and we'll fix or remove it promptly.
| Facility | City | Open / closed tanks | Status | EPA record |
|---|---|---|---|---|
| RTD Boulder | Boulder | 6 / 3 | Open UST(s) | CO9499 |
| Chans Foreign Cars | Boulder | 4 / 2 | Open UST(s) | CO2550 |
| Alta #6129 | Longmont | 4 / 1 | Open UST(s) | CO6262 |
| AJ Investments LLP Shortstop Gunbarrel | Boulder | 4 / 1 | Open UST(s) | CO6694 |
| CST Metro LLC DBA Corner Store #1110 | Boulder | 4 / 0 | Open UST(s) | CO4082 |
| McLane Western | Longmont | 4 / 0 | Open UST(s) | CO5241 |
| Costco Gasoline #480 | Superior | 4 / 0 | Open UST(s) | CO14880 |
| Twin Star Energy #536 | Boulder | 4 / 0 | Open UST(s) | CO6438 |
Open leak cleanups — most recently reported
| Site | City | Reported | Substance | EPA record |
|---|---|---|---|---|
| Puddle Corp DBA Puddle Car Wash | Boulder | 2018-08-17 | — | CO13111 |
| Centaur Food And Fuel | Lafayette | 2018-07-12 | — | CO13081 |
| Stinker Store #302 | Longmont | 2018-06-07 | — | CO13051 |
| All American Gas | Lafayette | 2018-02-09 | — | CO12951 |
| T3 Gas And Food | Lafayette | 2017-12-04 | — | CO12904 |
| AJ Investments LLP Shortstop Gunbarrel | Boulder | 2016-02-19 | — | CO12455 |
What this means if you're buying or lending here
- "Closed" ≠ clean. A closed tank was taken out of service per the registry — many were closed without soil testing, especially before the late 1990s.
- The registry is incomplete by design. Tanks removed before 1986 and most residential heating-oil tanks were never registered. A county with 417 registered facilities has an unknown number of unregistered ones.
- Open cleanups are the headline. 18 cases in this county are still open; contamination may still be under investigation or remediation — distance from a specific parcel is what matters, and that's a per-address question.
Screen a specific property
This page covers the county. A purchase or loan decision needs the registry around one address: registered tanks at the parcel, every facility within 500 and 1,500 ft, leak cleanups with status and distance — each line cited to the official record.
Screen an address — $49 How it worksThis is a screen of EPA-registered tank and leak records, not an environmental site assessment. State registries are incomplete by design: tanks removed before 1986 and most residential heating-oil tanks were never registered, so a clean screen cannot prove the absence of a tank. "Closed" means a tank was taken out of service per the registry — it does not certify that no contamination remains.
source: EPA UST Finder EPA data vintage 2024-12-04 computed 2026-06-12