St. Charles County contains 272 EPA-regulated facilities, 3 of which are currently flagged for significant noncompliance. The county also hosts 2 Superfund sites and 15 TRI chemical reporters. EPA has assessed $28.1k in lifetime penalties and TRI reporters disclosed roughly 1.1M lb of on-site releases. That facility count is well above the Missouri state average of 61 per county.
| Site | City | Status |
|---|---|---|
| Weldon Spring Quarry Plant Pits Usdoe Army | St. Charles | Ready for anticipated reuse |
| Weldon Spring Former Army Ordnance Works | St. Charles | Ready for anticipated reuse |
| Facility | City | On-site (lb) | Status |
|---|---|---|---|
| Ameren Missouri Sioux Energy Center | West Alton | 596.7k | Compliant |
| General Motors Llc Wentzville Assembly | Wentzville | 462.8k | Penalties |
| Superior Home Products Inc | Wentzville | 14.3k | Penalties |
| Modineer Plant 7 | Saint Peters | 5.0k | Compliant |
| Zoltek Corporation | Saint Peters | 2.4k | Compliant |
| Woodbridge Corporation - St. Peters | St. Peters | 414 | Compliant |
| Missouri Metals | Wentzville | 11 | Compliant |
| Facility | City | Penalties | Last Inspected |
|---|---|---|---|
| Quarry Wine Garden | New Melle | $0 | |
| Fred Weber Inc-O'fallon Stone Plant | O'fallon | $0 | 2025-05-16 |
| Safety-Kleen System | Saint Charles | $0 | 2025-04-24 |