Board of Directors

The Board of Directors of our General Partner, MarkWest Energy GP, L.L.C., oversees the management of our partnership and is comprised of nine members. One director is an officer of our General Partner or its affiliates, and eight are non-management, outside directors who meet the "independence" requirements of the New York Stock Exchange.


Frank M. Semple

Mr. Semple joined MarkWest on November 1, 2003. He is a member of the Board of Directors and was elected Chairman of the Board in October 2008. Prior to joining MarkWest he completed a 22-year career with The Williams Companies and WilTel Communications. He served as the Chief Operating Officer of WilTel Communications, Senior Vice President/General Manager of Williams Natural Gas Company, Vice President of Operations and Engineering for Northwest Pipeline Company and Division Manager for Williams Pipeline Company. Prior to joining The Williams Companies, Mr. Semple served in the U.S. Navy aboard the nuclear submarine USS Gurnard (SSN 662). Mr. Semple completed the Program for Management Development at Harvard Business School and a holds a B.S. in Mechanical Engineering degree from the United States Naval Academy.


Keith E. Bailey

Mr. Bailey was elected to the Board of Directors in January 2005. Mr. Bailey serves as Chairman of the Board's Compensation Committee and also serves on the Board's Nominating and Corporate Governance Committee. Mr. Bailey was formerly the Chairman, President and Chief Executive Officer of The Williams Companies, Inc. ("Williams"). Commencing in 1973, Mr. Bailey served in various capacities with Williams and its subsidiaries, including President and Chairman of Williams Pipe Line, Chairman of WilTel Communications, President of Williams Natural Gas, and Executive Vice President and Chief Financial Officer of Williams. Mr. Bailey also sits on the Boards for Integrys Energy, Apco Oil and Gas International, and Aegis Insurance Services Ltd, and is the non-executive Chairman of Cloud Peak Energy.


Michael L. Beatty

Mr. Beatty was elected to the Board of Directors in February 2008 and serves as the Chairman of the Board's Nominating and Corporate Governance Committee and also serves on the Board's Compensation Committee. Mr. Beatty previously served as a member of the Board of Directors of MarkWest Hydrocarbon, Inc. from June 2005 through February 2008. Mr. Beatty is currently Chairman of the law firm of Beatty & Wozniak, P.C. headquartered in Denver, Colorado, with a practice focused exclusively on energy, including oil and gas exploration, regulatory affairs, public lands, litigation and title. A Harvard Law School graduate, Mr. Beatty began his career in the energy industry as in-house counsel for Colorado Interstate Gas Company, and ultimately became Executive Vice President, General Counsel and a Director of The Coastal Corporation. He also served as Chief of Staff to Governor Roy Romer of Colorado. Mr. Beatty is also on the Board of Directors for Denbury Resources, Inc.


Charles K. Dempster

Mr. Dempster was elected to the Board of Directors in December 2002 and serves on the Compensation Committee and the Finance Committee. Mr. Dempster has more than 30 years of experience in the natural gas and power industry. He held various management and executive positions with Enron Corporation and its predecessors between 1969 and 1986, focusing on natural gas supply, transmission and distribution. From 1986 through 1992, Mr. Dempster served as President of Reliance Pipeline Company and Executive Vice President of Nicor Oil and Gas Corporation, oil and natural gas midstream and exploration subsidiaries of Nicor Inc. in Chicago. Prior to retiring, he served as President and Chief Executive Officer of Aquila Energy Company, an energy trading and gas midstream pipeline and processing organization in the US and UK, from 1993 through 2000.


Donald C. Heppermann

Mr. Heppermann has served as a member of the Board of Directors since its inception in May 2002, and was a member of the MarkWest Hydrocarbon's Board of Directors from November 2002 through February 2008. Mr. Heppermann serves as the Chairman of the Board's Finance Committee and also serves on the Board's Audit Committee. Mr. Heppermann joined our General Partner and MarkWest Hydrocarbon in November 2002 as Senior Vice President and Chief Financial Officer, and served as Senior Executive Vice President beginning in January 2003 and as Executive Vice President, Chief Financial Officer and Secretary of our General Partner and of MarkWest Hydrocarbon, Inc. from October 2003 until his retirement in March 2004. Prior to joining MarkWest, Mr. Heppermann was a private investor and a career executive in the energy industry with responsibilities in operations, finance, business development and strategic planning.


Randall J. Larson

Mr. Larson was elected to the Board of Directors in July 2011 and serves on the Board's Audit Committee and Compensation Committee. Mr. Larson was the Chief Executive Officer of the general partner of TransMontaigne Partners L.P. from September 2006 to August 2009. Mr. Larson also served as Chief Financial Officer of the general partner of TransMontaigne Partners L.P. from January 2003 to September 2006, and served as its Controller from May 2002 to January 2003. From July 1994 to May 2002, Mr. Larson was a partner with KPMG LLP in its Silicon Valley and National (New York City) offices. From July 1992 to July 1994, Mr. Larson served as a Professional Accounting Fellow in the Office of Chief Accountant of the Securities and Exchange Commission.


Anne E. Fox Mounsey

Ms. Fox Mounsey was elected to the Board of Directors in February 2008. Ms. Fox Mounsey serves on the Board's Audit Committee and Nominating and Corporate Governance Committee. Ms. Fox Mounsey previously served as a member of the Board of Directors of MarkWest Hydrocarbon, Inc. from October 2004 through February 2008. From 1991 to 2003, Ms. Mounsey held various positions with MarkWest Energy and MarkWest Hydrocarbon, her most recent as Manager of Marketing and Business Development.


William P. Nicoletti

Mr. Nicoletti has served as a member of the Board of Directors since its inception in May 2002. Mr. Nicoletti serves as Chairman of the Board's Audit Committee and also serves on the Board's Finance Committee. Mr. Nicoletti is a Managing Director of Parkman Whaling LLC, a Houston, Texas based energy investment banking firm. Previously, he was Managing Director of Nicoletti & Company Inc. and a Managing Director and head of Energy Investment Banking for PaineWebber Incorporated and E.F Hutton & Company Inc. Mr. Nicoletti was previously a director of Surge Global Energy, Inc. Mr. Nicoletti is a graduate of Seton Hall University and received an MBA from Columbia University Graduate School of Business. Mr. Nicoletti is a director and Chairman of the Audit Committee of Kestrel Heat LLC, the general partner of Star Gas Partners, L.P.


Donald D. Wolf

Mr. Wolf was elected to the Board of Directors in February 2008. He has served as the Lead Director since January 2010. Mr. Wolf previously served as a member of the board of directors of MarkWest Hydrocarbon, Inc. from June 1999 through February 2008. In September 2004, Mr. Wolf joined Aspect Energy, LLC as President and Chief Executive Officer, and currently serves as Vice Chairman. He is also Chairman and a Partner of Quantum Resources, LLC and QR Energy, LP. Mr. Wolf currently serves as a Director of Aspect Energy, Enduring Resources and Laredo Petroleum, Inc. Mr. Wolf previously served as Chairman, Chief Executive Officer and Director of Westport Resources Corporation from July 1996 until Westport's merger with Kerr McGee Corporation in 2004. Mr. Wolf has a diversified 40-year career in the oil and natural gas industry.