Clean Water Act discharge permit · NPDES MO0000299
MEMC, LLC, St. Peters, MO: NPDES MO0000299 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MajorDischarger class
- 21Pollutants under a numeric limit
- 10Pollutants with an effluent exceedance
MEMC, LLC, held by SunEdison Semiconductor, holds NPDES permit MO0000299, which discharges to Tributary To Belleau Creek. EPA’s file records it issued February 8, 2017 and expiring December 31, 2019. The status and dates are as EPA’s permit file stood when Velarion loaded it (October 14, 2026); EPA’s free Detailed Facility Report on ECHO carries the permit’s current standing.
Identity
| Facility as filed | MEMC, LLC |
|---|---|
| Permittee as filed | SunEdison Semiconductor |
| NPDES ID | MO0000299 |
| Permit status | Administratively continued (past its expiration date and still in force until reissued) |
| Permit type | Individual permit |
| Discharger class | Major discharger |
| Facility type | Not a publicly owned treatment works |
| Program | Industrial stormwater |
| Issued | February 8, 2017 |
| Expiration date | December 31, 2019 |
| Address | St. Peters, MO 63376 |
| Receiving water | Tributary to Belleau Creek |
| Subwatershed | Lower Dardenne Creek (HUC 071100090105) |
| NAICS | 334413 – Semiconductor and Related Device Manufacturing |
| SIC | 3674 – Semiconductors And Related Devices |
| Other EPA IDs (FRS) | RCRA handler MOD001700673; ICIS-AIR source MO0000002918300027 |
Cited to the EPA ICIS-NPDES permit file (ECHO download) and EPA’s NAICS/SIC and component files, the same download; cross-program IDs from EPA’s FRS facility-registry crosswalk.
Effluent limits and exceedances
- 30Pollutants on file
- 21Under a numeric limit
- 22With a violation of any kind
- 10With 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 |
|---|---|---|---|---|---|
| Chloride | 6 | 61 | 59 | June 30, 2026 | 251% over the limit |
| Fluoride, total [as F] | 6 | 12 | 8 | March 31, 2022 | 139% over the limit |
| BOD, 5-day, 20 deg. C | 0 | 8 | 8 | May 31, 2010 | 121% over the limit |
| Oil and grease [soxhlet extr.] tot. | 6 | 15 | 7 | December 31, 2018 | 69% over the limit |
| Solids, total suspended | 6 | 8 | 6 | June 30, 2010 | 313% over the limit |
| Chromium, total [as Cr] | 0 | 6 | 6 | June 30, 2010 | 315% over the limit |
| Trichloroethylene | 6 | 92 | 2 | June 30, 2010 | 1,100% over the limit |
| pH | 6 | 8 | 2 | July 31, 2026 | |
| Chromium, hexavalent dissolved [as Cr] | 6 | 6 | 2 | March 31, 2022 | 178% over the limit |
| Copper, total recoverable | 6 | 4 | 2 | June 30, 2022 | 76% over the limit |
| Flow, in conduit or thru treatment plant | 6 | 13 | 0 | ||
| Toxicity [chronic], Ceriodaphnia dubia | 1 | 10 | 0 | ||
| Toxicity [chronic], Pimephales promelas [Fathead Minnow] | 1 | 10 | 0 | ||
| Pass/Fail Static 48Hr Acute Ceriodaphnia dubia | 0 | 5 | 0 | ||
| LC50 Static 48Hr Acute Pimephales promelas | 0 | 5 | 0 | ||
| Sulfate [as S] | 6 | 2 | 0 | ||
| Chlorides + Sulfates | 6 | 2 | 0 | ||
| Nitrogen, total [as N] | 0 | 2 | 0 | ||
| Nitrogen, ammonia total [as N] | 0 | 2 | 0 | ||
| Nitrogen, Kjeldahl, total [as N] | 0 | 2 | 0 | ||
| Nitrite + Nitrate total [as N] | 0 | 2 | 0 | ||
| Toxicity [acute], Ceriodaphnia dubia | 0 | 1 | 0 | ||
| Solids, settleable | 6 | 0 | 0 | ||
| Arsenic, total recoverable | 6 | 0 | 0 | ||
| Precipitation volume | 6 | 0 | 0 | ||
| Silver total recoverable | 4 | 0 | 0 | ||
| Zinc, total recoverable | 4 | 0 | 0 | ||
| Temperature, water deg. fahrenheit | 2 | 0 | 0 | ||
| Silver, total [as Ag] | 2 | 0 | 0 | ||
| Zinc, total [as Zn] | 2 | 0 | 0 |
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
- 3Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| August 25, 2026 | Reporting Violations - Improper/ Incorrect Reporting | ST6 |
| May 24, 2024 | Effluent Violations - Numeric effluent violation | ST6 |
| April 3, 2024 | Effluent Violations - Numeric effluent violation | 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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Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.