# ENBRIDGE ENERGY, LIMITED PARTNERSHIP — Hazardous liquid — incident on 2010-07-28

**Citation:** PHMSA Report 20100184  
**Type / status:** incident / historical  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** 2010-07-28  
**Published:** 2010-08-27

Hazardous liquid incident in CASS LAKE, CASS County, MN. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 0.23 CRUDE OIL released, $18,352 reported property damage. Operator-reported incident data submitted to PHMSA, generally within 30 days. Records may be supplemented or corrected and do not represent final agency causal findings. PHMSA trend classification: not significant, not serious.

## Document text

Hazardous liquid incident in CASS LAKE, CASS County, MN. Reported cause: EQUIPMENT FAILURE. Reported consequences: 0 fatalities, 0 injuries, 0.23 CRUDE OIL released, $18,352 reported property damage. Operator-reported incident data submitted to PHMSA, generally within 30 days. Records may be supplemented or corrected and do not represent final agency causal findings.

Report number: 20100184.

Operator ID: 11169.

Reported incident date: 7/28/2010 7:45.

Location detail: 958.33

Cause detail: NON-THREADED CONNECTION FAILURE

Cause detail: ENBRIDGE FIELD LABORERS WORKING ALONG THE RIGHT-OF-WAY REPORTED SEEING EVIDENCE OF OIL ON THE GROUND AROUND A MAINLINE VALVE AT MP-958.33, WHICH IS LOCATED NORTH OF HWY 2 ON THE EAST SIDE OF CASS LAKE. THE LABORERS CONTACTED THEIR SUPERVISOR WHO CONFIRMED THE RELEASE AND MOBILIZED ENBRIDGE RESPONSE. LINES 1 AND 2 IN THIS ROUTE WERE SHUT DOWN AND VALVES ON EITHER SIDE OF THE LOCATION ISOLATED THE SECTION AS A PRECAUTION. THE PIPELINE MAINTENANCE SUPERVISOR, WHO RESPONDED TO THE SITE, CONFIRMED THE VALVE LEAK ON LINE 1 AND ESTIMATED A SMALL AMOUNT OF OIL HAD BEEN RELEASED ON THE GROUND AROUND THE VALVE. ENBRIDGE MAINTENANCE PERSONNEL EXCAVATED, BY HAND, THE SOIL AROUND THE SITE, EVALUATED THE VALVE CONDITION AND CONFIRMED THAT THE VALVE STEM PACKING WAS LEAKING. ENBRIDGE MAINTENANCE PERSONNEL WERE ABLE TO MAKE ON SITE REPAIRS TO THE VALVE STEM PACKING. ESTIMATED VOLUME RELEASED WAS 10 GALLONS. ONCE THE PACKING WAS REPAIRED, THE LINE WAS RESTARTED AT 17:45 PM LOCAL TIME. ALL AFFECTED SOIL HAS BEEN REMOVED AND DISPOSED AT AN APPROPRIATE OFF-SITE FACILITY. THE INCIDENT WAS REPORTED TO THE MN DUTY OFFICER AND THE NATIONAL RESPONSE CENTER. A REPRESENTATIVE FROM MNOPS VISITED TO INSPECT THE SITE.

PHMSA trend classification: not significant, not serious.

PHMSA standardized cause: EQUIPMENT FAILURE — NON-THREADED CONNECTION FAILURE.

PHMSA indexed costs: $18,352 reported total cost, $10,041.552 in 1984 dollars, $24,729.253 in current-year dollars.

PHMSA trend flags, standardized causes, and indexed costs are analytical fields added to operator-reported incident data. They do not represent final agency causal findings.

## Provenance

- Official: Yes
- Source: <https://data.transportation.gov/api/views/27nc-rsge/files/1d547e17-2be1-4a32-9958-a1d5a946ade9?download=true&filename=Hazardous%20Liquid%20Accident%20Data%20-%20January%202010%20to%20present.zip>
- Source ID: `phmsa-pipeline-incidents`
- SHA-256: `361177ae74895663eb3c2728fab142f259cf0923ac0c2bdc62aa124219aa954b`
- Retrieved: 2026-08-20T03:30:32.010Z
- Exported: 2026-08-24T16:32:51.485Z
- Document slug: `phmsa-incident-9f35e4e01e9b37b9357c540f`

### Source metadata

```json
{
  "recordKind": "pipeline_incident",
  "datasetType": "hazardous_liquid",
  "datasetLabel": "Hazardous liquid",
  "datasetPeriod": "January 2010 to present",
  "report": {
    "number": "20100184",
    "supplementalNumber": "15264",
    "type": "ORIGINAL FINAL",
    "receivedDate": "2010-08-27",
    "receivedDateRaw": "8/27/2010"
  },
  "operator": {
    "id": "11169",
    "name": "ENBRIDGE ENERGY, LIMITED PARTNERSHIP"
  },
  "incident": {
    "date": "2010-07-28",
    "dateRaw": "7/28/2010 7:45"
  },
  "location": {
    "city": "CASS LAKE",
    "county": "CASS",
    "state": "MN",
    "postalCode": "56633",
    "latitude": 47.372103,
    "longitude": -94.57539,
    "type": "PIPELINE RIGHT-OF-WAY",
    "details": {
      "DESIGNATED_NAME": "958.33"
    },
    "facilityName": "LINE 1"
  },
  "cause": {
    "category": "EQUIPMENT FAILURE",
    "details": {
      "CAUSE_DETAILS": "NON-THREADED CONNECTION FAILURE",
      "NARRATIVE": "ENBRIDGE FIELD LABORERS WORKING ALONG THE RIGHT-OF-WAY REPORTED SEEING EVIDENCE OF OIL ON THE GROUND AROUND A MAINLINE VALVE AT MP-958.33, WHICH IS LOCATED NORTH OF HWY 2 ON THE EAST SIDE OF CASS LAKE. THE LABORERS CONTACTED THEIR SUPERVISOR WHO CONFIRMED THE RELEASE AND MOBILIZED ENBRIDGE RESPONSE. LINES 1 AND 2 IN THIS ROUTE WERE SHUT DOWN AND VALVES ON EITHER SIDE OF THE LOCATION ISOLATED THE SECTION AS A PRECAUTION. THE PIPELINE MAINTENANCE SUPERVISOR, WHO RESPONDED TO THE SITE, CONFIRMED THE VALVE LEAK ON LINE 1 AND ESTIMATED A SMALL AMOUNT OF OIL HAD BEEN RELEASED ON THE GROUND AROUND THE VALVE. ENBRIDGE MAINTENANCE PERSONNEL EXCAVATED, BY HAND, THE SOIL AROUND THE SITE, EVALUATED THE VALVE CONDITION AND CONFIRMED THAT THE VALVE STEM PACKING WAS LEAKING. ENBRIDGE MAINTENANCE PERSONNEL WERE ABLE TO MAKE ON SITE REPAIRS TO THE VALVE STEM PACKING. ESTIMATED VOLUME RELEASED WAS 10 GALLONS. ONCE THE PACKING WAS REPAIRED, THE LINE WAS RESTARTED AT 17:45 PM LOCAL TIME. ALL AFFECTED SOIL HAS BEEN REMOVED AND DISPOSED AT AN APPROPRIATE OFF-SITE FACILITY. THE INCIDENT WAS REPORTED TO THE MN DUTY OFFICER AND THE NATIONAL RESPONSE CENTER. A REPRESENTATIVE FROM MNOPS VISITED TO INSPECT THE SITE."
    }
  },
  "consequences": {
    "fatalities": 0,
    "injuries": 0,
    "commodity": "CRUDE OIL",
    "release": "0.23",
    "propertyDamage": 18352,
    "estimatedOperatorCost": null,
    "estimatedEmergencyCost": 3500,
    "estimatedEnvironmentalCost": 14852,
    "ignition": "NO",
    "explosion": "NO",
    "evacuated": null,
    "raw": {
      "FATAL": "0",
      "INJURE": "0",
      "UNINTENTIONAL_RELEASE_BBLS": "0.23",
      "PRPTY": "18352"
    }
  },
  "provenance": {
    "viewId": "27nc-rsge",
    "viewUrl": "https://data.transportation.gov/api/views/27nc-rsge",
    "assetId": "1d547e17-2be1-4a32-9958-a1d5a946ade9",
    "archiveFilename": "Hazardous Liquid Accident Data - January 2010 to present.zip",
    "archiveSha256": "5aaa1a31834a0503acfdfc82172d9ff3483b480019cec1605ebb8e15d0040f0d",
    "memberPath": "accident_hazardous_liquid_jan2010_present.txt",
    "memberSha256": "2af519107224bbd22874e67c65f6aa526073a297b2b30104b711d071680488a4",
    "rowNumber": 5654,
    "rowSha256": "e3c97923410292fa022b7b7aca68119fa0032bf7b4549542beda52b071b6081c"
  },
  "caveat": "Operator-reported incident data submitted to PHMSA, generally within 30 days. Records may be supplemented or corrected and do not represent final agency causal findings.",
  "operatorReported": true,
  "finalAgencyFinding": false,
  "flaggedAnalysis": {
    "dataAsOf": "2026-07-31",
    "flags": {
      "fireFirst": null,
      "significant": false,
      "serious": false
    },
    "standardizedCause": {
      "sevenCategory": "MATERIAL/WELD/EQUIP FAILURE",
      "sevenSubcategory": "NON-THREADED CONNECTION FAILURE",
      "eightCategory": "EQUIPMENT FAILURE",
      "eightSubcategory": "NON-THREADED CONNECTION FAILURE"
    },
    "costs": {
      "reported": 18352,
      "in1984Dollars": 10041.552462081867,
      "currentYearDollars": 24729.253272387276
    },
    "caveat": "PHMSA trend flags, standardized causes, and indexed costs are analytical fields added to operator-reported incident data. They do not represent final agency causal findings.",
    "provenance": {
      "sourceUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/data_statistics/pipeline/PHMSA_Pipeline_Safety_Flagged_Incidents.zip",
      "landingPageUrl": "https://www.phmsa.dot.gov/data-and-statistics/pipeline/pipeline-incident-flagged-files",
      "catalogUrl": "https://data.transportation.gov/Pipelines-and-Hazmat/Pipeline-Incident-Flagged-Files/qdme-9bbm",
      "retrievalMode": "official_live",
      "archivedAt": null,
      "archiveSha256": "317e6a3e16d60b9b677efe391dc40258b5dd7ead83fb8bea74cb553cedfbbdec",
      "workbook": "hl2010toPresent.xlsx",
      "sheet": "hl2010toPresent",
      "rowNumber": 179,
      "rowSha256": "eb8569b59456067b2faabefd818b889f9fe61d93d5ccd2101b4669545d0a8013"
    }
  },
  "jurisdiction": "US",
  "operatorName": "ENBRIDGE ENERGY, LIMITED PARTNERSHIP"
}
```
