On October 19, 2021, the board of directors (the ?Board?) of Montrose Environmental Group, Inc. (the ?Company?) increased the size of the Board to nine members and appointed Ms. Janet Risi Field as a director to fill the newly created vacancy. Ms. Risi will serve as a Class II director until the company?s 2022 Annual Meeting of Stockholders or until her successor is duly elected and qualified. The Board affirmatively determined that Ms. Risi is an independent director within the meaning of the New York Stock Exchange listing standards. There are no arrangements or understandings between Ms. Risi and any other persons pursuant to which she was elected as a director of the Company. There are no family relationships between Ms. Risi and any director or executive officer of the Company, and she has no direct or indirect material interest in any transaction required to be disclosed pursuant to Item 404(a) of Regulation S-K.