Leadership Team

Board of Directors

Executive Leadership Team

Bruce Fleming


Bruce A. Fleming has served as Executive Vice President — Montana Renewables & Corporate Development of our general partner since February 2021. From March 2016 until the appointment to his current position, Mr. Fleming served as Executive Vice President – Strategy & Growth of our general partner. Prior to joining the Company, Mr. Fleming served as the Vice President of Mergers & Acquisitions at Tesoro Corporation and as an officer of Tesoro Companies Inc. since 2004. From 1997 through 2004, Mr. Fleming served as Managing Director of Hong Kong-based Orient Refining Ltd., and from 1981 through 1996 he held senior operations, business development and planning roles with Amoco Oil and Amoco Corporation where he was most recently Vice President of China business development. Mr. Fleming earned a Ph.D. in chemical engineering from Princeton University and a B.S. in chemical engineering from the University of Delaware. He is a member of the Board of M&A Standards.


Mark Wilson


Mark is responsible for developing and executing external growth strategies for Montana Renewables. He joined Calumet in July of 2023 and assumed the role of Vice President, Mergers, Acquisitions & Commercial Development for Montana Renewables. The prior two years he was supporting Montanan Renewable’s Commercial activity through a consulting arrangement. Mark has over 30 years of industry experience and brings a broad industry background from his time working at Marathon (previously Tesoro) where he spent twenty years on its leadership team. In his last position Mark was responsible for Marathon’s entry into Mexico, serving as Vice President Latin America. Prior to that Mark served as Vice President for several functions including Enterprise Integration, Marine, Commercial Operations, Business Development and Wholesale Marketing. He holds a Bachelor of Science in Management Finance from Park University.


Dan Carlson


Daniel L. Carlson, P.E., joined Montana Renewables in April 2022 as Vice President Strategy and Development. Dan has over 40 years of industry experience. He is responsible for identifying and developing commercial growth and operational enhancements for feedstocks, products and physical assets for Montana Renewables. He previously held roles including Process Engineer, Project Manager, Process Engineering Manager, Technical Manager, Operations Manager, Vice President – Refinery Manager, and Vice President – Planning and Optimization for Tosco, Ultramar Diamond Shamrock, Tesoro Corporation and Andeavor Corporation. Dan earned his BS in Chemical Engineering from the University of California, Berkeley, his MBA from Saint Mary’s College of California, and is a registered Professional Engineering in California.


Michael Wojciechowski


Michael Wojciechowski, or Wojo to his friends and colleagues, joined Calumet in 2018 as Director of Strategy and Growth with over 24 years of experience in the industry. He assumed his current role as Commercial and Compliance Director for Montana Renewables since its inception.  He is responsible for directing the value optimization for the feedstock supply and product offtake arrangements, as well as assuring compliance with the various jurisdictions and programs for renewable fuels.  He previously held roles in Process Engineering, Lab Operations, Optimization Planning, Market Analysis, and Management with Wood Mackenzie, Merrill Lynch Commodities, Tesoro Corporation, and Mustang Engineering.  Wojo earned his BS in Chemical Engineering from Texas A&M University and an MBA from the Kelley School at Indiana University.


Derek Roesener


Derek Roesener joined Calumet in 2014 and has 28 years of experience in finance and accounting. He assumed his current role as Director of Finance – Montana Renewables in 2021. In this role, he is responsible for directing and coordinating the financial functions of MRL. Prior to this role at Calumet, Derek was Director of Strategy where he coordinated several divesture and acquisition transitions at Calumet. Derek has served in various industry roles as CFO, Director of Finance, Assistant Treasurer, Business Unit Controller and Tax Manager for Magnatech Manufacturing, Brightpoint North America and Delco Remy after working 6 years at Arthur Andersen. Derek earned his B.S. degree from Cornell University and M.S. degree from the Krannert School of Management at Purdue University.

Leading the Energy Transformation

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