Clean Water Act discharge permit · NPDES OK0000256
PHILLIPS 66 COMPANY-PONCA CITY REFINERY, Ponca City, OK: NPDES OK0000256 discharge permit, effluent exceedances, inspections, penalties
- Administratively continuedPermit status
- MajorDischarger class
- 28Pollutants under a numeric limit
- 7Pollutants with an effluent exceedance
- 0Inspections on file
- 1Formal enforcement actions
PHILLIPS 66 COMPANY-PONCA CITY REFINERY, held by Phillips 66 Company-Ponca City Refinery, holds NPDES permit OK0000256, which discharges to 621200 Arkansas-001/Omaha Ck-002/ Hoover Ditch-003. EPA’s file records it issued December 16, 2016 and expiring December 31, 2021.
PHILLIPS 66 COMPANY-PONCA CITY REFINERY, Ponca City, Oklahoma: Individual permit OK0000256, held by Phillips 66 Company-Ponca City Refinery; Administratively continued (past its expiration date and still in force until reissued); issued December 16, 2016, term to December 31, 2021, by ODEQ; discharges to 621200 Arkansas-001/Omaha Ck-002/ Hoover Ditch-003; Petroleum Refineries.
- pH: 12 limits, 55 violations of any kind, 27 effluent exceedances, latest July 31, 2025.
- Sulfide, total [as S]: 4 limits, 24 violations of any kind, 12 effluent exceedances, latest September 30, 2025, largest 358% over the limit.
- Oxygen demand, chem. [high level] [COD]: 8 limits, 28 violations of any kind, 10 effluent exceedances, latest March 31, 2021, largest 94% over the limit.
- Oil and grease, hexane extr method: 8 limits, 26 violations of any kind, 8 effluent exceedances, latest June 30, 2026, largest 99,999% over the limit.
- BOD, 5-day, 20 deg. C: 4 limits, 17 violations of any kind, 5 effluent exceedances, latest March 31, 2021, largest 93% over the limit.
- Nitrogen, ammonia total [as N]: 8 limits, 22 violations of any kind, 2 effluent exceedances, latest March 31, 2005, largest 136% over the limit.
- Solids, total suspended: 9 limits, 23 violations of any kind, 1 effluent exceedance, latest June 30, 2019, largest 39% over the limit.
- Flow, in conduit or thru treatment plant: 8 limits, 18 violations of any kind, 0 effluent exceedances.
- Solids, total dissolved- 180 deg. C: 5 limits, 18 violations of any kind, 0 effluent exceedances.
- Phenolics, total recoverable: 4 limits, 14 violations of any kind, 0 effluent exceedances.
- Chromium, total [as Cr]: 4 limits, 12 violations of any kind, 0 effluent exceedances.
- Chromium, hexavalent [as Cr]: 4 limits, 8 violations of any kind, 0 effluent exceedances.
- Selenium, total [as Se]: 4 limits, 8 violations of any kind, 0 effluent exceedances.
- LC50 Static Renewal 48Hr Acute Pimephales promelas: 2 limits, 5 violations of any kind, 0 effluent exceedances.
- LC50 Static Renewal 48Hr Acute Pimephales promelas: 2 limits, 5 violations of any kind, 0 effluent exceedances.
- % Mortality Static Renewal 48 Hr Pimephales promelas or use TJA6C: 2 limits, 5 violations of any kind, 0 effluent exceedances.
- Oil & Grease: 1 limit, 4 violations of any kind, 0 effluent exceedances.
- Benzene: 1 limit, 4 violations of any kind, 0 effluent exceedances.
- Carbon, tot organic [TOC]: 0 limits, 4 violations of any kind, 0 effluent exceedances.
- pH range excursions, > 60 minutes: 0 limits, 4 violations of any kind, 0 effluent exceedances.
- pH range excursions, monthly total accum: 0 limits, 4 violations of any kind, 0 effluent exceedances.
- LC50 Static Renewal 48Hr Acute Daphnia pulex: 0 limits, 4 violations of any kind, 0 effluent exceedances.
- LC50 Static Renewal 48Hr Acute Daphnia magna: 1 limit, 3 violations of any kind, 0 effluent exceedances.
- LF Pass/Fail Static Renewal 48Hr Acute Daphnia magna: 1 limit, 3 violations of any kind, 0 effluent exceedances.
- Daphnia Magna % Mortality 48 Hr Acute: 1 limit, 3 violations of any kind, 0 effluent exceedances.
- BTEX: 1 limit, 2 violations of any kind, 0 effluent exceedances.
- Chlorine, total residual: 1 limit, 2 violations of any kind, 0 effluent exceedances.
- Total Petroleum Hydrocarbons - Diesel: 1 limit, 2 violations of any kind, 0 effluent exceedances.
- Total Petroleum Hydrocarbons - Gasoline: 1 limit, 2 violations of any kind, 0 effluent exceedances.
- Toluene: 0 limits, 2 violations of any kind, 0 effluent exceedances.
- LC50 Pass/Fail Static Renewal 48Hr Acute Daphnia Pulex: 0 limits, 2 violations of any kind, 0 effluent exceedances.
- %Mortality Static Renewal 48Hr Acute Daphnia Pulex: 0 limits, 2 violations of any kind, 0 effluent exceedances.
- Whole effluent toxicity: 1 limit, 1 violation of any kind, 0 effluent exceedances.
- Whole effluent toxicity - retest #1: 2 limits, 0 violations of any kind, 0 effluent exceedances.
- Whole effluent toxicity - retest #2: 2 limits, 0 violations of any kind, 0 effluent exceedances.
- August 28, 2026: State CWA Non Penalty AO (State).
- June 26, 2026: Effluent Violations - Unapproved Bypass (ST6).
- June 19, 2019: Permit Violations - Violation Specified in Comment (ST6).
- February 14, 2018: Permit Violations - Violation Specified in Comment (ST6).
PHILLIPS 66 COMPANY-PONCA CITY REFINERY among its neighbors
EPA’s permit file holds 1 discharge permits in the City of Ponca City-Arkansas River subwatershed (HUC 110600010504), OK0000256 among them. Its county holds 5, 1 of them major permits; OK0000256 is a major permit.
Identity
| Facility as filed | PHILLIPS 66 COMPANY-PONCA CITY REFINERY |
|---|---|
| Permittee as filed | Phillips 66 Company-Ponca City Refinery |
| NPDES ID | OK0000256 |
| 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 |
| Issued | December 16, 2016 |
| Expiration date | December 31, 2021 |
| Issuing agency | ODEQ |
| Address | Ponca City, OK 74601 |
| Receiving water | 621200 Arkansas-001/Omaha Ck-002/ Hoover Ditch-003 |
| Subwatershed | City of Ponca City-Arkansas River (HUC 110600010504) |
| NAICS | 324110 – Petroleum Refineries |
| SIC | 2911 – Petroleum Refining |
| Other EPA IDs (FRS) | RCRA handler OKR000027789; ICIS-AIR source OK0000004007100010 |
Effluent limits and exceedances
- 35Pollutants on file
- 28Under a numeric limit
- 33With a violation of any kind
- 7With 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 |
|---|---|---|---|---|---|
| pH | 12 | 55 | 27 | July 31, 2025 | |
| Sulfide, total [as S] | 4 | 24 | 12 | September 30, 2025 | 358% over the limit |
| Oxygen demand, chem. [high level] [COD] | 8 | 28 | 10 | March 31, 2021 | 94% over the limit |
| Oil and grease, hexane extr method | 8 | 26 | 8 | June 30, 2026 | 99,999% over the limit |
| BOD, 5-day, 20 deg. C | 4 | 17 | 5 | March 31, 2021 | 93% over the limit |
| Nitrogen, ammonia total [as N] | 8 | 22 | 2 | March 31, 2005 | 136% over the limit |
| Solids, total suspended | 9 | 23 | 1 | June 30, 2019 | 39% over the limit |
| Flow, in conduit or thru treatment plant | 8 | 18 | 0 | ||
| Solids, total dissolved- 180 deg. C | 5 | 18 | 0 | ||
| Phenolics, total recoverable | 4 | 14 | 0 | ||
| Chromium, total [as Cr] | 4 | 12 | 0 | ||
| Chromium, hexavalent [as Cr] | 4 | 8 | 0 | ||
| Selenium, total [as Se] | 4 | 8 | 0 | ||
| LC50 Static Renewal 48Hr Acute Pimephales promelas | 2 | 5 | 0 | ||
| LC50 Static Renewal 48Hr Acute Pimephales promelas | 2 | 5 | 0 | ||
| % Mortality Static Renewal 48 Hr Pimephales promelas or use TJA6C | 2 | 5 | 0 | ||
| Oil & Grease | 1 | 4 | 0 | ||
| Benzene | 1 | 4 | 0 | ||
| Carbon, tot organic [TOC] | 0 | 4 | 0 | ||
| pH range excursions, > 60 minutes | 0 | 4 | 0 | ||
| pH range excursions, monthly total accum | 0 | 4 | 0 | ||
| LC50 Static Renewal 48Hr Acute Daphnia pulex | 0 | 4 | 0 | ||
| LC50 Static Renewal 48Hr Acute Daphnia magna | 1 | 3 | 0 | ||
| LF Pass/Fail Static Renewal 48Hr Acute Daphnia magna | 1 | 3 | 0 | ||
| Daphnia Magna % Mortality 48 Hr Acute | 1 | 3 | 0 | ||
| BTEX | 1 | 2 | 0 | ||
| Chlorine, total residual | 1 | 2 | 0 | ||
| Total Petroleum Hydrocarbons - Diesel | 1 | 2 | 0 | ||
| Total Petroleum Hydrocarbons - Gasoline | 1 | 2 | 0 | ||
| Toluene | 0 | 2 | 0 | ||
| LC50 Pass/Fail Static Renewal 48Hr Acute Daphnia Pulex | 0 | 2 | 0 | ||
| %Mortality Static Renewal 48Hr Acute Daphnia Pulex | 0 | 2 | 0 | ||
| Whole effluent toxicity | 1 | 1 | 0 | ||
| Whole effluent toxicity - retest #1 | 2 | 0 | 0 | ||
| Whole effluent toxicity - retest #2 | 2 | 0 | 0 |
Inspections, violations and enforcement
- 3Single-event violations
| Date | What EPA recorded | Agency |
|---|---|---|
| June 26, 2026 | Effluent Violations - Unapproved Bypass | ST6 |
| June 19, 2019 | Permit Violations - Violation Specified in Comment | ST6 |
| February 14, 2018 | Permit Violations - Violation Specified in Comment | ST6 |
Inspections
EPA’s inspection file holds no inspection for NPDES OK0000256.
Formal enforcement and penalties
1 formal actions, 0 of them with a penalty assessed. Federal and state penalties are separate figures from separate authorities and are shown as each was filed, never added together.
| Date | What EPA recorded | Agency | Federal penalty | State or local penalty |
|---|---|---|---|---|
| August 28, 2026 | State CWA Non Penalty AO | State |
Informal enforcement
EPA’s informal enforcement file holds no action for NPDES OK0000256.
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Figures from EPA’s ICIS-NPDES download, loaded October 14, 2026.