#1 The restricted stock units were acquired pursuant to the PDC Energy, Inc. Amended and Restated 2010 Long-Term Equity Compensation Plan and will vest on May 24, 2024.

#1 Pursuant to that certain Agreement and Plan of Merger dated August 20, 2024 (the "Merger Agreement") by and among the Issuer, CONSOL Energy Inc. ("CONSOL"), and Mountain Range Merger Sub Inc., a wholly owned subsidiary of CONSOL ("Merger Sub"), Merger Sub merged with and into the Issuer (the "Merger"), with the Issuer continuing as the surviving corporation and a direct, wholly owned subsidiary of CONSOL. At the effective time of the Merger (the "Effective Time"), each share of common stock the Issuer (the "Arch Common Stock") issued and outstanding immediately prior to the Effective Time (other than certain excluded shares) was converted into the right to receive 1.326 shares of common stock of CONSOL ("CONSOL Common Stock") (such number of shares, the "Per-Share Merger Consideration").