# EDGAR Filing Document

**Accession Number:** 0001710366
**File Stem:** 0001710366-26-000034
**Filing Date:** 2026-5
**Character Count:** 5365
**Document Hash:** cec64e9f632331804022f97f0271a2a6
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001710366-26-000034.hdr.sgml**: 20260504

**ACCESSION NUMBER**: 0001710366-26-000034

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 11

**CONFORMED PERIOD OF REPORT**: 20260429

**ITEM INFORMATION**: Mine Safety - Reporting of Shutdowns and Patterns of Violations

**FILED AS OF DATE**: 20260504

**DATE AS OF CHANGE**: 20260504

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Core Natural Resources, Inc.
- **CENTRAL INDEX KEY:** 0001710366
- **STANDARD INDUSTRIAL CLASSIFICATION:** BITUMINOUS COAL & LIGNITE MINING [1220]
- **ORGANIZATION NAME:** 01 Energy & Transportation
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DC
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38147
- **FILM NUMBER:** 26938294

**BUSINESS ADDRESS:**
- **STREET 1:** 275 TECHNOLOGY DRIVE
- **STREET 2:** SUITE #101
- **CITY:** CANONSBURG
- **STATE:** PA
- **ZIP:** 15317
- **BUSINESS PHONE:** 724-416-8300

**MAIL ADDRESS:**
- **STREET 1:** 275 TECHNOLOGY DRIVE
- **STREET 2:** SUITE #101
- **CITY:** CANONSBURG
- **STATE:** PA
- **ZIP:** 15317

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CONSOL Energy Inc.
- **DATE OF NAME CHANGE:** 20171128

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CONSOL Mining Corp
- **DATE OF NAME CHANGE:** 20170626

?xml version='1.0' encoding='ASCII'? cnr-20260429

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549** 

**FORM 8-K**

**CURRENT REPORT**

**PURSUANT TO SECTION 13 OR 15(d) OF THE**

**SECURITIES EXCHANGE ACT OF 1934**

**Date of Report (Date of earliest event reported): April 29, 2026**

**Core Natural Resources, Inc.**

**(Exact name of registrant as specified in its charter)**

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| | | |
|:---|:---|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;**Delaware** | &nbsp;&nbsp;&nbsp;&nbsp;**001-38147** | &nbsp;&nbsp;&nbsp;&nbsp;**82-1954058** |
| **(State or other jurisdiction of incorporation)** | &nbsp;&nbsp;&nbsp;&nbsp;**(Commission File Number)** | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;**(IRS Employer**<br>**Identification No.)** |

---

**275 Technology Drive Suite 101**

**Canonsburg, Pennsylvania 15317**

**(Address of principal executive offices)**

**(Zip code)**

**Registrant's telephone number, including area code:**

**(724) 416-8300** 

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

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| | | |
|:---|:---|:---|
| **<u>Title of each class</u>** | **<u>Trading Symbol(s)</u>** | **<u>Name of each exchange on which registered</u>** |
| Common Stock, $0.01 par value | CNR | New York Stock Exchange |

---

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

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**Item 1.04 Mine Safety – Reporting of Shutdowns and Patterns of Violations.**

On April 29, 2026, Mingo Logan Coal LLC, a subsidiary of Core Natural Resources, Inc., received an imminent danger order under section 107(a) of the Federal Mine Safety and Health Act of 1977 at the Mountaineer II mine located in Logan County, West Virginia. The order states that an inspector found an accumulation of elevated methane levels at an air intake entry while equipment was energized in the mining section. Methane levels between the intake entry and the stopping line at certain crosscuts were in excess of 5.0%, and methane levels varied in the center of the intake entry from 1.0% to 2.2%. Mine personnel promptly took appropriate actions to alleviate the condition and to restore acceptable methane levels. The Mine Safety and Health Administration terminated the 107(a) order on the same day, and no injuries or illnesses resulted from the temporary condition.

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**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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| | |
|:---|:---|
| &nbsp;&nbsp;&nbsp;&nbsp;**Core Natural Resources, Inc.** | &nbsp;&nbsp;&nbsp;&nbsp;**Core Natural Resources, Inc.** |
| &nbsp;&nbsp;&nbsp;&nbsp;**(Registrant)** | &nbsp;&nbsp;&nbsp;&nbsp;**(Registrant)** |
| &nbsp;&nbsp;&nbsp;&nbsp;By: | /s/ MITESHKUMAR B. THAKKAR |
|  | &nbsp;&nbsp;&nbsp;&nbsp;Miteshkumar B. Thakkar |
|  | &nbsp;&nbsp;&nbsp;&nbsp;President and Chief Financial Officer |

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Dated: May 4, 2026