Methane issue triggers mine safety order at Core (NYSE: CNR)
Filing Impact
Filing Sentiment
Form Type
8-K
Rhea-AI Filing Summary
Core Natural Resources, Inc. reported a mine safety event involving its subsidiary Mingo Logan Coal LLC at the Mountaineer II mine in Logan County, West Virginia. On April 29, 2026, the mine received an imminent danger order under section 107(a) of the Federal Mine Safety and Health Act of 1977.
The order followed an inspector’s finding of elevated methane levels at an air intake entry while equipment was energized. Methane between the intake entry and the stopping line at certain crosscuts exceeded 5.0%, and levels in the center of the intake entry ranged from 1.0% to 2.2%. Mine personnel promptly acted to reduce methane and restore acceptable levels.
The Mine Safety and Health Administration terminated the 107(a) order the same day, and no injuries or illnesses resulted from this temporary condition.
Positive
- None.
Negative
- None.
8-K Event Classification
Item 1.04 — Mine Safety - Reporting of Shutdowns and Patterns of Violations
1 item
Item 1.04
Mine Safety - Reporting of Shutdowns and Patterns of Violations
Business
Mine safety violations, closure orders, or patterns of safety issues at mining operations.
Key Figures
Methane level maximum: Above 5.0%
Methane range in intake center: 1.0% to 2.2%
Order type: Section 107(a) imminent danger order
+1 more
4 metrics
Methane level maximum
Above 5.0%
Between intake entry and stopping line at certain crosscuts
Methane range in intake center
1.0% to 2.2%
Center of air intake entry
Order type
Section 107(a) imminent danger order
Federal Mine Safety and Health Act of 1977
Order timing
April 29, 2026
Imminent danger order issued and terminated same day
Key Terms
imminent danger order, section 107(a), Federal Mine Safety and Health Act of 1977, Mine Safety and Health Administration, +1 more
5 terms
imminent danger order regulatory
"received an imminent danger order under section 107(a) of the Federal Mine Safety and Health Act of 1977"
section 107(a) regulatory
"received an imminent danger order under section 107(a) of the Federal Mine Safety and Health Act of 1977"
Federal Mine Safety and Health Act of 1977 regulatory
"under section 107(a) of the Federal Mine Safety and Health Act of 1977 at the Mountaineer II mine"
Mine Safety and Health Administration regulatory
"The Mine Safety and Health Administration terminated the 107(a) order on the same day"
The Mine Safety and Health Administration (MSHA) is a U.S. federal agency that sets and enforces safety and health standards for mining operations, conducts inspections, investigates accidents, and issues citations or fines. Its actions matter to investors because safety rules, enforcement actions, or accident findings can increase operating costs, interrupt production, create legal and cleanup liabilities, and damage a miner’s reputation—similar to how building inspections or traffic enforcement affect a company’s ability to operate smoothly.
emerging growth company regulatory
"Emerging growth company"
An emerging growth company is a recently public or smaller public firm that qualifies for temporary, lighter regulatory and disclosure rules to reduce the cost and effort of being public. For investors, it means the company may provide less historical financial detail and face fewer reporting requirements than larger firms, so it can grow more quickly but also carries higher uncertainty—like buying a promising early-stage product with fewer user reviews.
FAQ
What mine safety incident did Core Natural Resources (CNR) report?
Core Natural Resources reported an imminent danger order at its Mountaineer II mine in West Virginia. An inspector found elevated methane levels at an air intake entry while equipment was energized, triggering a section 107(a) order under the Federal Mine Safety and Health Act of 1977.
How high were methane levels in the Core Natural Resources (CNR) mine incident?
Methane levels between the intake entry and the stopping line at certain crosscuts were above 5.0%. In the center of the intake entry, methane ranged from 1.0% to 2.2%, leading to issuance of an imminent danger order until conditions were corrected and levels normalized.
How quickly was the mine safety order at Core Natural Resources (CNR) resolved?
The Mine Safety and Health Administration terminated the section 107(a) imminent danger order the same day it was issued. Mine personnel promptly took actions to reduce methane concentrations and restore acceptable levels, allowing regulators to end the order without ongoing restrictions.
Did the Core Natural Resources (CNR) methane incident cause injuries or illnesses?
No injuries or illnesses resulted from the methane-related condition at the Mountaineer II mine. After elevated methane levels were detected, mine personnel acted promptly to fix the problem, and the Mine Safety and Health Administration terminated the imminent danger order the same day.
Which subsidiary of Core Natural Resources (CNR) was involved in the safety order?
Mingo Logan Coal LLC, a subsidiary of Core Natural Resources, received the imminent danger order at the Mountaineer II mine. The order was issued under section 107(a) after elevated methane levels were found and was later terminated the same day following corrective actions.