Martha Z. Carnes

Chair of the Audit Committee

Martha Z. Carnes, age 61, has served as an independent director of the Company since July 2017. Ms. Carnes retired from PricewaterhouseCoopers LLP ("PwC") in June 2016, where she had a thirty-four year career with the firm. She was an assurance partner serving large, publicly traded companies in the energy industry. Ms. Carnes held a number of leadership positions with PwC including the Houston office Managing Partner. She also served as PwC's Energy and Mining leader in the United States where she led the firm's energy and mining assurance, tax, and advisory practices. Ms. Carnes also served as one of PwC's Risk Management Partners and was PwC's United States representative on the firm's Global Communities Board. She also serves on the Supervisory Board of Core Laboratories N.V., a Netherlands company that provides reservoir description and production enhancement services to the oil and gas industry, and is the Chairman of the Audit Committee. Effective September 1, 2017, Ms. Carnes was appointed to the board of directors of SunCoke Energy Partners GP LLC, the general partner of SunCoke Energy Partners LP. She serves on both the audit and conflicts committees. Ms. Carnes is the Chairman of the Governing Board of the Greater Houston Community Foundation, and has chaired their Compensation, Strategy, and Finance & Administration Committees. She is also a member of the Board of Trustees at Texas Children's Hospital where she serves on the Audit and Compliance; Operations, Planning and Development; and Risk Management and Insurance Committees. Ms, Carnes received her B.B.A. in accounting from the University of Texas at Austin and she is a certified public accountant.

The specific experience, qualifications, attributes or skills that led to the conclusion Ms. Carnes should serve as a Director include her extensive expertise in financial oversight, financial reporting and broad accounting knowledge gained from working with and auditing public companies in the energy industry and her operational and leadership experience at PwC.

Independent Director