---
schema_version: "secwatch.filing_event.v1"
accession: "0001710366-26-000002"
form_type: "8-K"
ticker: "CNR"
cik: "0001710366"
company_name: "Core Natural Resources, Inc."
filed_at: "2026-01-12T23:59:59+00:00"
generated_at: "2026-05-16T10:54:06.382587+00:00"
event_type: "regulatory"
sentiment: "negative"
materiality_score: 0.4
confidence: "high"
source: SEC EDGAR
---

# Core Natural Resources subsidiary receives imminent danger order at Mountaineer II mine due to elevated methane

## Summary
- Mingo Logan Coal LLC received a 107(a) order on January 8, 2026 at the Mountaineer II mine in Logan County, West Virginia.
- An inspector found elevated methane levels in an isolated section; mine personnel restored acceptable levels promptly.
- The Mine Safety and Health Administration terminated the order, and no injuries or illnesses resulted.
- Core Natural Resources, Inc. (NYSE: CNR) is the parent company of Mingo Logan Coal LLC.

## SEC filing metadata
- accession: 0001710366-26-000002
- form_type: 8-K
- ticker: CNR
- cik: 0001710366
- company_name: Core Natural Resources, Inc.
- filed_at: 2026-01-12T23:59:59+00:00
- event_type: regulatory
- sentiment: negative
- materiality_score: 0.4
- confidence: high
- sec_items: 1.04
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1710366/000171036626000002/0001710366-26-000002-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1710366/000171036626000002/cnr-20260108.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001710366-26-000002
- JSON: https://secwatch.observer/filing/0001710366-26-000002.json
- Plain text: https://secwatch.observer/filing/0001710366-26-000002.txt

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.