| Violation ID |
Occurred Date |
Violation Type |
(-) Violation Description |
Corrective Action |
Status |
Classification |
Source |
| 1152913 |
02/11/2026 |
DMON |
During the week of Feb 8 our sump transfer pumps were broken at our D2 sanitary sewer, so the sewage had to be vacuumed out of the sump with a vacuum truck. Historically whenever this happened, we would offload the sewage in the vacuum truck at the other sanitary sewer sump (D1). In those cases, we would only sample at D1 since that one sample would be representative of the sewage from both locations. During that time, instead of offloading at the D1 sanitary sewer sump, the vacuum trucks offloaded at our pump station 1 oily sewer sump instead due to miscommunication. Because we thought that the D2 sewage was being offloaded at the D1 sanitary sewer sump, we only collected a sample at D1 that week and did not collect a sample at D2. We had full bleach injection flowing that whole week at the D2 sanitary sewer, and site staff noted that the bleach in the sump was 10mg/L using test strips, so we expect that the enterococcus was non-detect as usual during the week that we did not sample. |
We are creating a sanitary sewer vacuum truck offload instruction that states sewage from one sanitary sewer can only be offloaded into the opposite sanitary sewer (D1 to D2, or D2 to D1). |
Violation |
U |
eSMR |
| 1150153 |
11/13/2025 |
CAT1 |
Total Organic Carbon (TOC) Maximum Daily (MDEL) limit is 110 mg/L and reported value was 150 mg/L at E-005-T2NW. |
Performed extra cleaning at and around the discharge location. |
Violation |
U |
eSMR |
| 1147855 |
08/01/2025 |
CAT2 |
TCDD Equivalents Daily Maximum limit is 0.028 pg/L and reported value was 0.0339 pg/L at E-001. |
We are still investigating the cause of the dioxin exceedance. We have no evidence that we are generating dioxins in our renewable fuels processes or in our current wastewater streams. Wastewater leaving our wastewater treatment plant produces non-detect results for dioxins. |
Violation |
U |
eSMR |
| 1147831 |
07/31/2025 |
CAT2 |
TCDD Equivalents Monthly Average limit is 0.014 pg/L and reported value was 0.038 pg/L at E-001. |
We are still investigating what may be causing the exceedances. We have no evidence that we are generating dioxins in our renewable fuels processes or in our current wastewater streams. Wastewater leaving our wastewater treatment plant produces non-detect results for dioxins. |
Violation |
U |
eSMR |
| 1147830 |
07/28/2025 |
CAT2 |
TCDD Equivalents Maximum Daily (MDEL) limit is 0.028 pg/L and reported value was 0.0478 pg/L at E-001. |
We are still investigating what may be causing the exceedances. We have no evidence that we are generating dioxins in our renewable fuels processes or in our current wastewater streams. Wastewater leaving our wastewater treatment plant produces non-detect results for dioxins. |
Violation |
U |
eSMR |
| 1147829 |
07/25/2025 |
CAT2 |
TCDD Equivalents Maximum Daily (MDEL) limit is 0.028 pg/L and reported value was 0.051 pg/L at E-001. |
We are still investigating what may be causing the exceedances. We have no evidence that we are generating dioxins in our renewable fuels processes or in our current wastewater streams. Wastewater leaving our wastewater treatment plant produces non-detect results for dioxins. |
Violation |
U |
eSMR |
| 1147832 |
07/16/2025 |
CAT2 |
TCDD Equivalents Maximum Daily (MDEL) limit is 0.028 pg/L and reported value was 0.074 pg/L at E-001. |
We are still investigating what may be causing the exceedances. We have no evidence that we are generating dioxins in our renewable fuels processes or in our current wastewater streams. Wastewater leaving our wastewater treatment plant produces non-detect results for dioxins. |
Violation |
U |
eSMR |
| 1138785 |
12/31/2024 |
LREP |
Monthly SMR ( MONNPDES ) report for November 2024 (2585521) was due on 30-DEC-24 |
|
Violation |
B |
Report |
| 1125317 |
01/31/2024 |
DMON |
The BOD sample collected on January 31st was submitted to the analytical laboratory 5 hours outside of its 48-hour hold time. Although analyzed outside of hold time, the results showed that the sample was in the normal range for our E-001 BOD (3.95 mg/L), and was an order of magnitude below our average weekly NPDES permit limit (45 mg/L). |
The wastewater compliance contract staff used on site to collect and submit our NPDES compliance samples was retrained on the importance of meeting hold times for compliance samples. NPDES samples must now be submitted to the analytical laboratory the same day as collected, unless there is permission from Marathon environmental staff to do otherwise. |
Violation |
U |
eSMR |
| 1123441 |
12/31/2023 |
CAT2 |
TCDD Equivalents Daily Maximum limit is 0.028 pg/L and reported value was 0.056 pg/L at E-001. |
Investigatory dioxin sampling was completed throughout our WWTP system to track and understand any dioxins that may exist in the wastewater. These samples showed that dioxins in our wastewater settle out as they make their way through our ponds, and are completely removed by the combination of clarifier, filter, and GAC treatment. An investigation is underway to determine why dioxins were found in our E-001 final effluent. |
Violation |
U |
eSMR |
| 1123444 |
12/31/2023 |
CAT2 |
TCDD Equivalents Monthly Average limit is .014 pg/L and reported value was 0.039 pg/L at E-001. |
Investigatory dioxin sampling was completed throughout our WWTP system to track and understand any dioxins that may exist in the wastewater. These samples showed that dioxins in our wastewater settle out as they make their way through our ponds, and are completely removed by the combination of clarifier, filter, and GAC treatment. An investigation is underway to determine why dioxins were found in our E-001 final effluent. |
Violation |
U |
eSMR |
| 1123440 |
12/30/2023 |
CAT2 |
TCDD Equivalents Daily Maximum limit is 0.028 pg/L and reported value was 0.070 pg/L at E-001. |
Investigatory dioxin sampling was completed throughout our WWTP system to track and understand any dioxins that may exist in the wastewater. These samples showed that dioxins in our wastewater settle out as they make their way through our ponds, and are completely removed by the combination of clarifier, filter, and GAC treatment. An investigation is underway to determine why dioxins were found in our E-001 final effluent. |
Violation |
U |
eSMR |
| 1123443 |
12/29/2023 |
CAT2 |
TCDD Equivalents Daily Maximum limit is 0.028 pg/L and reported value was 0.044 pg/L at E-001. |
Investigatory dioxin sampling was completed throughout our WWTP system to track and understand any dioxins that may exist in the wastewater. These samples showed that dioxins in our wastewater settle out as they make their way through our ponds, and are completely removed by the combination of clarifier, filter, and GAC treatment. An investigation is underway to determine why dioxins were found in our E-001 final effluent. |
Violation |
U |
eSMR |
| 1123439 |
12/27/2023 |
CAT2 |
TCDD Equivalents Daily Maximum limit is 0.028 pg/L and reported value was 0.049 pg/L at E-001. |
Investigatory dioxin sampling was completed throughout our WWTP system to track and understand any dioxins that may exist in the wastewater. These samples showed that dioxins in our wastewater settle out as they make their way through our ponds, and are completely removed by the combination of clarifier, filter, and GAC treatment. An investigation is underway to determine why dioxins were found in our E-001 final effluent. |
Violation |
B |
eSMR |
| 1123438 |
12/26/2023 |
CAT2 |
TCDD Equivalents Daily Maximum limit is 0.028 pg/L and reported value was 0.031 pg/L at E-001. |
Investigatory dioxin sampling was completed throughout our WWTP system to track and understand any dioxins that may exist in the wastewater. These samples showed that dioxins in our wastewater settle out as they make their way through our ponds, and are completely removed by the combination of clarifier, filter, and GAC treatment. An investigation is underway to determine why dioxins were found in our E-001 final effluent. |
Violation |
U |
eSMR |
| 1123442 |
12/07/2023 |
CAT2 |
TCDD Equivalents Daily Maximum limit is 0.028 pg/L and reported value was 0.029 pg/L at E-001. |
Investigatory dioxin sampling was completed throughout our WWTP system to track and understand any dioxins that may exist in the wastewater. These samples showed that dioxins in our wastewater settle out as they make their way through our ponds, and are completely removed by the combination of clarifier, filter, and GAC treatment. An investigation is underway to determine why dioxins were found in our E-001 final effluent.
|
Violation |
U |
eSMR |
| 1106372 |
02/28/2022 |
DMON |
Per cover letter, "the monthly sample for biological oxygen demand (BOD) was not analyzed at the laboratory due to dissolved oxygen (DO) results. It is believed that the invalid dissolved oxygen results were the result of algae in the wastewater indicating that the BOD should be non-detect. The BOD results in the DMR were coded as NODI P = Laboratory Error or Invalid Test. The Refinery will continue to work with the lab to
resolve this issue either be reissuing the report with the corrected analysis or submitting a retain sample for BOD." |
|
Violation |
B |
Report |
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Report displays most recent five years of violations. Refer to the Interactive Violation Report for more data.
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