Clean Fuels Alliance Staff
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Officers

Donnell Rehagen
Chief Executive Officer
With more than 115 member companies, Clean Fuels Alliance America is the leading U.S. organization representing the biodiesel, renewable diesel and sustainable aviation fuel industries. As Chief Executive Officer, Donnell works closely with Clean Fuels Alliance America’s board of directors to ensure the industry has a clear, sharp vision of the future – full of growth and opportunity for the members it serves. Donnell provides leadership to Clean Fuels’ passionate staff made up of advocacy, technical, environmental science and communications professionals with a dedicated drive to see the industry reach its vision of six billion gallons of demand by 2030.
Donnell joined Clean Fuels Alliance America in 2004 as its Chief Operating Officer and assumed the role of Chief Executive Officer in 2016. Donnell has master’s in public administration from the University of Missouri – Columbia and a bachelor’s degree in Computer Information Systems from Missouri State University.

Doug Whitehead
Chief Operating Officer
As Chief Operating Officer, Doug ensures that Clean Fuels Alliance America’s strategic plan, fund development, programs and procedures support the needs of our growing industry. Doug works continuously to improve operations for the company and the Clean Fuels team has the resources and tools they need to execute materials for our valued members. Doug stays closely tuned in to Clean Fuels’ operations and staff, ensuring each team member is best utilized to enhance the clean fuels industry.
Doug has over 18 years of experience in the biodiesel space and 15 years in local elected office. He also spent time managing Clean Fuels Alliance America’s work in Washington D.C., supporting the reinstatement of the biodiesel tax credit, defending the Renewable Fuel Standard Program and fighting against trade cases on illegally traded biodiesel imports.
In 2002, Doug became Clean Fuels Alliance America’s first in-house State Regulatory Director. He served as Director of Operations & Membership from 2008-2017 and assumed the role of Chief Operating Officer in 2017. Born and raised in Missouri, Doug graduated from Kansas State University and currently lives in Jefferson City, MO, where Clean Fuels Alliance America is headquartered.

April Yaeger
Chief Financial Officer
April serves as the Chief Financial Officer for Clean Fuels Alliance America, managing all aspects of financial operations for our organization. April serves as liaison to the board’s finance and investment committee, as well as the audit committee. She works to develop policies for financial accountant matters and manages resources to maintain a smooth operation of the organizations Clean Fuels Alliance America represents. In addition to her vast financial role, April also oversees human resources for Clean Fuels, communicating all benefits and policies to our employees.
With April’s rich finance background, Clean Fuels Alliance America also called upon her to assist with the Clean Fuels Foundation and Clean Fuels PAC.
April graduated from Southwest Missouri State University with a Bachelor of Science in Accounting. April joined the Clean Fuels Alliance America in 2006. Prior to joining Clean Fuels Alliance America, she was the CFO for a not-for-profit service organization for 10 years.
Accounting

Desiree Hale
Accounting Specialist
Desiree serves as an Accounting Specialist for Clean Fuels Alliance America. Desiree is responsible for processing accounts payable, payroll and other reimbursement projects. She also serves as the Staff Liaison for the BQ-9000 Program, a quality systems program that includes storage, sampling, testing, blending, shipping, distribution and fuel management practices.
Desiree joined Clean Fuels Alliance America in 2005 with a diverse background in Long Term Care business management and Municipal Government financial services.

Anne Klempke
Accounting Specialist
Anne serves as an Accounting Specialist for Clean Fuels Alliance America. Anne is responsible for processing Accounts Receivable, Fixed Assets and other reimbursement projects. She also maintains the Clean Fuels Alliance America membership database.
Anne graduated from Columbia College with a Bachelor of Science in Business Administration, with a major in Accounting. Prior to joining Clean Fuels Alliance America, she served 20 years in the US Army.
Communications

Heather Buechter
Director of Communications
Heather serves as Director of Communications for Clean Fuels Alliance America, responsible for supporting efforts to continue to grow the biodiesel, renewable diesel and sustainable aviation fuel industry and share our vision, leading efforts to craft and share messages on the industry’s plans to move from 3 to 6 billion gallons by 2030, as well as promoting Clean Fuels Alliance America and the members it serves.
Before joining Clean Fuels Alliance America, Heather was the Director of Communications for the Missouri Catholic Conference. After earning a B.A. in Communication from the University of Arkansas, she spent 12 years as a broadcast journalist. Heather, an Arkansas native, brings extensive experience crafting stories that invoke change, building community relationships and adapting to changing demands.

Katherine Reed
Senior Communications Manager
Katherine serves as the Senior Communications Manager for Clean Fuels Alliance America. In this role, she supports the implementation of the association’s communications plan, educates stakeholders on the industry’s mission, manages Clean Fuels’ social media channels and coordinates with partner organizations to ensure consistent messaging.
Reed earned her Bachelor of Science in Business Administration with a focus in Marketing and Management from Columbia College. With over 10 years of marketing and communications experience, she most recently served as Director of Communications for Friends of the Missouri Governor’s Mansion. Katherine brings to Clean Fuels a wealth of experience in creative marketing strategies and public relations.
Economics and Market Analytics

Jonathan Martin
Director of Economics and Market Analytics
Jonathan Martin serves as Director of Economics and Market Analytics for Clean Fuels Alliance America, responsible for monitoring market data and current events to provide in-depth market intelligence and forecasts on the direction of the market. Jonathan leads a team focused on modeling and forecasting the direction of liquid fuels, energy markets, and feedstock markets. Jonathan also supports state and federal affairs staff on economic inquiries and fundamentals research.
Prior to joining Clean Fuels Alliance America, Jonathan was an Economist at Marathon Petroleum Corporation, where he led economic and market analyses and forecasts in the oil and gas market. Jonathan has also worked both in process engineering and environmental compliance between multiple refineries within Marathon’s portfolio. He has a Bachelor of Science in Chemical Engineering from Rose-Hulman Institute of Technology.
Environmental Science/Sustainability

Veronica Bradley
Director of Environmental Science
Veronica Bradley serves as Director of Environmental Science for Clean Fuels Alliance America where she leads the advancement of education and research on the climate and public health benefits of bio-based diesel and sustainable aviation fuels. In this role, Veronica educates relevant stakeholders on the environmental benefits of clean fuels and works with industry to identify and execute on relevant research needs. This work ensures feedstock and producer members’ products are accurately assessed for their climate benefits and are appropriately accounted for in reporting by end users and policymakers.
Prior to joining Clean Fuels Alliance America, Veronica was Director of Environmental Affairs at Airlines for America where she assisted in environmental advocacy activities relating to aircraft and airline operations. She was previously a Research Associate at ICF where she supported the Climate Change and Stratospheric Ozone Protection Divisions for the U.S. Environmental Protection Agency. A Michigan native, Veronica received her Bachelor of Arts degree with distinction from the University of Michigan and a Juris Doctor magna cum laude from American University Washington College of Law.
Federal Affairs

Kurt Kovarik
Vice President, Federal Affairs
Kurt serves as Vice President, Federal Affairs for Clean Fuels Alliance America, leading members in advocating federal policies that support the industry’s growth. Since joining Clean Fuels Alliance America, Kurt has helped the industry secure a long-term extension of the biodiesel tax incentive, preserve important protections against unfair international trade and ensure the integrity of the Renewable Fuel Standard program. Kurt continues to organize the industry’s advocacy for equitable tax, infrastructure and environmental policies.
Prior to joining Clean Fuels Alliance America, Kurt worked for more than 20 years in the office of Senator Chuck Grassley (R-IA), leading efforts on the Renewable Fuel Standard, the biodiesel tax incentive and increased use of clean fuels. An Iowa native, Kurt graduated from Luther College with a degree in political science.

Kate Shenk
Director of Regulatory Affairs
Kate serves as Director of Regulatory Affairs for Clean Fuels Alliance America, leading members in navigating federal regulatory policies. Since joining Clean Fuels Alliance America, Kate has helped the industry advocate for growth in annual Renewable Fuel Standard rules, eligibility for grants in USDA infrastructure incentive program and a prominent role in addressing the climate crisis. Kate leads the industry’s efforts to secure equitable treatment of biodiesel and renewable diesel and their diverse feedstocks in EPA, DOE and USDA programs.
Kate brings to Clean Fuels Alliance America extensive knowledge of the Clean Air Act and related regulatory policies.
Kate earned a Master of Science in environmental policy at Bard Center for Environmental Policy, Bard College in New York. She also is the immediate past president of Women in Government Relations, a non-partisan professional society in Washington.

David Cobb
Director of Federal Affairs
David serves as Director of Federal Affairs for Clean Fuels Alliance America, advocating for Congressional support of Clean Fuels Alliance America’s policy priorities. Since joining Clean Fuels Alliance America, David has helped the industry identify and foster new Congressional champions and organize successful advocacy events. David leads industry efforts to secure federal support for biodiesel infrastructure in emerging markets and currently serves as Treasurer of the Clean Fuels Political Action Committee.
Prior to joining Clean Fuels Alliance America, David was Director of Federal Affairs for CHS Inc., the nation’s largest farmer owned cooperative. David was previously Legislative Assistant for agriculture and natural resources issues to Senator Max Baucus (D-MT) and on the staff of Senator Mary Landrieu (D-LA). David is a native of Ruston, LA and earned a B.A. from Louisiana Tech University.

Paul Winters
Director of Public Affairs and Federal Communications
Paul serves as Director of Public Affairs and Federal Communications for Clean Fuels Alliance America, leading communications efforts and media outreach on federal policy priorities, including the Renewable Fuel Standard. Since joining Clean Fuels Alliance America, Paul has helped members build robust relationships with members of Congress and provided effective tools to educate stakeholders about the effectiveness of federal policies and the benefits of biodiesel and renewable diesel.
Paul brings to Clean Fuels Alliance America extensive experience in media relations and advocacy on the RFS and other federal policies. Paul earned a bachelor’s degree at UCLA and a master’s degree at the University of California, Davis, in political science and international relations.
Information Management

Bev Thessen
Information Coordinator
Bev serves as the Information Coordinator for Clean Fuels Alliance America. Bev has been employed with Clean Fuels Alliance America since 1994 and plays a significant role as first point of contact for the office, whether by incoming calls or e-mail requests. In addition, Bev assists with Clean Fuels Alliance America’s website, database management and communications outreach. Another key responsibility is taking minutes for membership, the Governing Board and many of Clean Fuels Alliance America’s working groups. Bev keeps staff up to date by reviewing and routing newsletters, articles and information about upcoming meetings.
Prior to joining Clean Fuels Alliance America, Bev was employed by the Missouri Department of Natural Resources’ Hazardous Waste Program.
Operations and Membership

Brad Shimmens
Director of Operations and Membership
Brad serves as the Director of Operations and Membership for Clean Fuels Alliance America. Brad is responsible for the design and execution, in collaboration with all staff, of a comprehensive membership outreach and communication program which is reviewed and adjusted as needed on an annual basis. He is responsible for recruiting (assisting with the application process) new members, assisting members with questions and providing information and documentation to new and current members. Also, he is responsible for coordinating, administrating and reporting all program related contracts for funding and for subcontracting as well as for the identification and development of alternative revenue sources. Brad also works with staff to host meetings and events throughout the country for Clean Fuels members.
Brad attended The University of Missouri and graduated with a BS in Finance. He then pursued and completed his MBA from William Woods University. Prior to joining Clean Fuels Alliance America, he worked for Central BanCompany in many capacities, most recently as a Commercial Loan Officer. He comes to Clean Fuels Alliance America with a background in finance, business development and community outreach.
Outreach and Development

Tom Verry
Director of Outreach and Development
Tom serves as the Director of Outreach and Development for Clean Fuels Alliance America. Tom works to establish synergistic relationships for the benefit of the biodiesel industry with key stakeholders including feed stock suppliers, state soybean associations, fuel suppliers, end-users, policy makers, government agencies and environmental/ health groups. Tom also works to identify and access resources that will address the needs of the organization and the industry.
Previously, Tom spent 12 years as the Director of Field Services for the Missouri Soybean Association. Tom was responsible for developing soy based industrial products and turning them into value-added opportunities for Missouri soybean producers. Tom has worked on biodiesel for twelve years in Missouri helping to develop state biodiesel policies, regulations and markets. Tom is a 1987 graduate of University of Illinois with a Bachelor of Science degree in Agricultural Economics.
State Affairs

Floyd Vergara
Director of State Governmental Affairs
Floyd Vergara serves as the Director of State Governmental Affairs for Clean Fuels Alliance America. In this capacity, he manages the West Coast office in Sacramento, CA and manages a team of professionals responsible for government affairs in all 50 states.
Before joining Clean Fuels Alliance America, Floyd served as Chief and Assistant Chief in the Industrial Strategies Division and Research Division at the California Air Resources Board. With over three decades of experience at CARB, his expertise includes the Low Carbon Fuels Standard, climate change and air quality programs, renewable and conventional fuels, environmental justice and other environmental issues. Floyd is a licensed Professional Engineer with a BS in chemical engineering from the University of California, Berkeley and a licensed attorney with a JD from the University of the Pacific, McGeorge School of Law.

Steve Dodge
Director of State Regulatory Affairs
Steve serves as the Director of State Regulatory Affairs for Clean Fuels Alliance America. In this role, he engages in technical analysis of issues associated with biodiesel and renewable diesel and represent the interests of Clean Fuels Alliance America’s members to state regulatory bodies, state legislatures and state environmental organizations. Housed on the East Coast, his primary focus is on advancing state and regional policy efforts for biodiesel, renewable diesel and Bioheat® fuel home heating oil in the Northeast.
Previously, Steve held positions as the American Petroleum Institute’s Executive Director and Associate Director of the Massachusetts/New England Petroleum Council, Director of the Massachusetts Governor’s legislative office and other staff positions in the state department of revenue and state legislature.

Jeff Earl
Director of State Regulatory Affairs
Jeff Earl serves as the Director of State Regulatory Affairs for Clean Fuels Alliance America from Jefferson City, Missouri, covering the Midwest states on behalf of the association. As the director of state regulatory affairs, Earl will engage in technical analysis of issues associated with biodiesel and represent the interests of Clean Fuels Alliance America’s members to state regulatory bodies, legislatures and environmental organizations.
Earl comes to Clean Fuels Alliance America from the Office of Missouri Governor, where he held the position of legislative director. Previously, he served in leadership positions with the Department of Corrections and Office of the State Auditor. Earl holds a bachelor’s degree in political science and mass communications from Southeast Missouri State University.
Technical

Scott Fenwick
Technical Director
Scott serves as the Technical Director for Clean Fuels Alliance America, working in the Jefferson City, MO headquarters. Scott leads the advancement of core member services for technical and quality assurance support issues. Scott provides key support for technical aspects needed by biodiesel stakeholders including both producer members, obligated parties and fuel users to effectively position the biodiesel industry. Additionally, he educates key decision makers to help build industry credibility. In addition to coordinating the OEM and fuel quality programs under Clean Fuels Alliance America, Scott has also been elected to chair the ASTM D02 Committee covering all Petroleum Products, Liquid Fuels and Lubricants. He also coordinates other international biodiesel and fuel activities for other standards development organizations. After serving as Chairman of the BQ-9000 Commission, Scott now assists as the Clean Fuels Alliance America liaison to the National Biodiesel Accreditation Commission.
Prior to joining Clean Fuels Alliance America, Scott had been involved with the fuel inspection industry for nearly 25 years and managed several fuel testing laboratories. After attending Purdue University, he also worked for Archer Daniels Midland Company organizing their Biofuels Technical Services.
Information Technology/Web Services

Scott Tremain
Technical Director
Information Technology Director
Scott serves as the Information Technology Director for Clean Fuels Alliance America, responsible for the strategic direction and implementation of Clean Fuels Alliance America’s information, technology, computing, and networking systems.
A graduate of the University of Central Missouri, Scott joined Clean Fuels Alliance America in 2002 and oversees all aspects of information technology management and control, including operation and maintenance of all computing and telecommunications systems, equipment, and services; budget preparation; recommendations for technical acquisitions; and development of guidelines, standards and procedures. Scott directs the effective delivery of networks, development, and disaster recovery systems and processes.