Clean Water Act discharge permit · NPDES MTR000511
STILLWATER MINING COMPANY, Nye, MT: NPDES MTR000511 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MinorDischarger class
- 15Pollutants under a numeric limit
- 0Pollutants with an effluent exceedance
STILLWATER MINING COMPANY holds NPDES permit MTR000511, which discharges to Un-Named Tributary To Little Rocky Creek. EPA’s file records it issued May 16, 2018 and expiring January 31, 2023. The status and dates are as EPA’s permit file stood when Velarion loaded it (September 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
Identity
| Facility as filed | STILLWATER MINING COMPANY |
|---|---|
| Permittee as filed | STILLWATER MINING COMPANY |
| NPDES ID | MTR000511 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Coverage under a general permit |
| Discharger class | Minor discharger |
| Facility type | Not a publicly owned treatment works |
| Program | Industrial stormwater |
| Issued | May 16, 2018 |
| Expiration date | January 31, 2023 |
| Address | Nye, MT 59061 |
| Receiving water | Un-named tributary to Little Rocky Creek |
| Receiving water impaired | 303(D) Listed |
| Subwatershed | Stillwater River-Mountain View Creek (HUC 100700050204) |
Cited to the EPA ICIS-NPDES permit file (ECHO download).
Effluent limits and exceedances
- 15Pollutants on file
- 15Under a numeric limit
- 15With a violation of any kind
- 0With an effluent exceedance
An effluent exceedance is a discharge monitoring report value over the permit’s numeric limit (EPA’s violation code E90). A violation of any kind also counts a report not filed. Each row is EPA’s own count for that pollutant.
| Pollutant or measure | Limits | Violations, any kind | Effluent exceedances | Latest exceedance | Largest exceedance, as filed |
|---|---|---|---|---|---|
| Beryllium, total [as Be] | 5 | 22 | 0 | ||
| Cadmium, total [as Cd] | 5 | 21 | 0 | ||
| Silver, total [as Ag] | 5 | 20 | 0 | ||
| Antimony, total [as Sb] | 5 | 20 | 0 | ||
| pH | 10 | 19 | 0 | ||
| Arsenic, total [as As] | 5 | 19 | 0 | ||
| Selenium, total [as Se] | 5 | 19 | 0 | ||
| Nickel, total [as Ni] | 5 | 18 | 0 | ||
| Mercury, total [as Hg] | 5 | 18 | 0 | ||
| Iron, total [as Fe] | 5 | 17 | 0 | ||
| Lead, total [as Pb] | 5 | 17 | 0 | ||
| Solids, total suspended | 5 | 16 | 0 | ||
| Copper, total [as Cu] | 5 | 16 | 0 | ||
| Zinc, total [as Zn] | 5 | 16 | 0 | ||
| Hardness, total [as CaCO3] | 5 | 11 | 0 |
EPA’s effluent violation file records no exceedance of a numeric limit for NPDES MTR000511.
Cited to the EPA ICIS-NPDES limits and effluent violations files (ECHO download); up to 60 rows shown, most exceedances first.
Inspections, violations and enforcement
- 6Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| March 5, 2025 | Management Practice Violations - Failure to Maintain Records | ST6 |
| March 5, 2025 | Effluent Violations - Unapproved Bypass | ST6 |
| March 5, 2025 | Permit Violations - Application Incomplete | ST6 |
| March 5, 2025 | Monitoring Violations - Invalid/Unrepresentative Sample | ST6 |
| March 5, 2025 | Permit Violations - Violation Specified in Comment | ST6 |
| March 5, 2025 | Reporting Violations - Improper/ Incorrect Reporting | ST6 |
Velarion’s copy of EPA’s ICIS-NPDES files does not include the inspections, formal enforcement actions and informal enforcement actions files, so this page shows none of them. EPA’s free Detailed Facility Report on ECHO lists this permit’s inspections, enforcement actions and penalties.
Cited to the EPA ICIS-NPDES violation, inspection and enforcement files (ECHO download); up to 50 rows of each shown, newest first.
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EPA publishes a free Detailed Facility Report for every permit on ECHO: its compliance status quarter by quarter, its inspections, and its enforcement actions and penalties. EPA also sends free notices of new inspections and enforcement actions through ECHO Notify; enter NPDES ID MTR000511 there.
Nearby on the register
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- Every permit record in Montana, A to Z
Figures from EPA’s ICIS-NPDES download, loaded September 14, 2026.