# NORTHWESTERN CORPORATION — Liberty County, MT

**Citation:** NPMS FIPS 30051 / OPID 31632  
**Type / status:** inspection / current  
**Agency:** Pipeline and Hazardous Materials Safety Administration  
**Effective:** Not stated  
**Published:** 2026-07-16

27.351934 active Natural Gas pipeline miles in Liberty County, MT; public NPMS snapshot 2026-07-16.

## Document text

NORTHWESTERN CORPORATION (PHMSA OPID 31632) reported 27.351934 active Natural Gas pipeline miles in Liberty County, MT (county FIPS 30051) in the public NPMS summary snapshot dated 2026-07-16. The snapshot includes active assets only and excludes permanently abandoned assets. Exact pipeline locations and restricted NPMS GIS data are not included.

## Provenance

- Official: Yes
- Source: <https://www.npms.phmsa.dot.gov/Documents/NPMS_Active_Pipe_County_Mileage.xlsx>
- Source ID: `npms-public-summaries`
- SHA-256: `b3a4b28762d531da8f0a90f7cd2dc0351e5a6d3862033b11e4af3bae4f9ae2a4`
- Retrieved: 2026-08-20T04:38:11.081Z
- Exported: 2026-08-25T17:38:37.703Z
- Document slug: `npms-mileage-9b49a627a313752973fa30ce`

### Source metadata

```json
{
  "materialSubtype": "pipeline_mileage",
  "dataAsOf": "2026-07-16",
  "dateBasis": "data_as_of_not_publication_date",
  "fips": "30051",
  "stateFips": "30",
  "state": "MT",
  "county": "Liberty County",
  "region": "Liberty County, MT",
  "operator": {
    "id": "31632",
    "name": "NORTHWESTERN CORPORATION"
  },
  "commodity": "Natural Gas",
  "mileage": 27.35193372,
  "plantCount": null,
  "snapshotScope": "active_assets_only",
  "personalContactDataExcluded": true,
  "restrictedGisExcluded": true,
  "provenance": {
    "workbook": "pipeline_mileage",
    "sheet": "Summary - Cnty, Oper, Commodity",
    "rowNumber": 7121,
    "rowSha256": "93d31483c1640b0001ccf0c9618d9f4e58fdfc193f56228ebaeff15cb83d20ee"
  },
  "citedSections": [
    "191.29"
  ],
  "caveat": "Public aggregate snapshot only. It is not a complete representation of exact pipeline locations, may be updated, and is not an agency finding about facility condition.",
  "jurisdiction": "US",
  "operatorName": "NORTHWESTERN CORPORATION"
}
```