One Matrix: Four Operating Companies

Matrix is proud to consistently earn certification by Great Place to Work, the global authority on high-trust, high-performance workplace cultures. In the US, it produces the annual Fortune “100 Best Companies to Work For®” list. This is our ninth year in a row to apply and to be certified as a Great Place to Work!

Matrix’s South Korea fabrication facility received ISO 9001:2015 re-certification for the management system in the manufacturing of aboveground storage tanks and tank parts.

Engineering News-Record names Matrix #165 on its annual Top 400 Contractors List. Matrix additionally ranked highly in the following sub-categories: #10 among petroleum contractors and #33 working abroad.

Matrix is proud to consistently earn certification by Great Place to Work, the global authority on high-trust, high-performance workplace cultures. In the US, it produces the annual Fortune “100 Best Companies to Work For®” list.

Matrix is proud to consistently earn certification by Great Place to Work, the global authority on high-trust, high-performance workplace cultures. In the US, it produces the annual Fortune “100 Best Companies to Work For®” list.

John R. Hewitt has been President and Chief Executive Officer at Matrix Service Company since May 2011. Prior to joining Matrix Service, Mr. Hewitt served as Senior Vice President of Aker Solutions where he was responsible for providing executive oversight on major capital projects in Power and LNG. He previously served as President, United States Operations, at Aker Solutions E&C US, Inc. from 2007 to 2009 where he was responsible for managing all construction services in North America. Previous to that, he served as President of Aker Construction Inc. where he had full profit and loss responsibility for a multi-disciplined direct hire industrial construction business operating throughout North America. Mr. Hewitt has spent his entire career in the engineering, procurement, and construction (EPC) industry. Mr. Hewitt earned a Bachelor of Business Administration degree in Finance from Stetson University in 1980 and a Bachelor of Science degree in Civil Engineering from Florida Institute of Technology in 1983. Mr. Hewitt is a member of the Construction Industry Institute; he has served on various committees including the Implementation Strategy Sub-Committee and Optimizing Project Organizations research committee.

Kevin S. Cavanah has served as Chief Financial Officer since December, 2010. Mr. Cavanah served as Vice President, Accounting and Financial Reporting from August 2007 to December 2010 and as Controller from April 2003 to August 2007. Prior to joining the Company, Mr. Cavanah served as an Accounting Manager for Williams Communications from 2001 to 2003 and as an Accounting Manager for The Williams Companies from 1998 to 2001. Prior to joining Williams Companies, Mr. Cavanah served as an Audit Manager for Ernst & Young LLP. Mr. Cavanah has a Bachelor of Science Degree in Business Administration in Accounting from the University of Arkansas and is a member of Financial Executives International.

Nancy E. Austin is Vice President and Chief Administrative Officer, with responsibility for leading our Human Resources, Training and Development, and Corporate Marketing divisions. She previously served as Vice President, Strategic Services and Administration, with responsibility for these same areas. Mrs. Austin served as Vice President, Human Resources, from January 2006 to August 2016 and as Director of Human Resources from September 2000 to January 2006. Prior to joining the Company, Mrs. Austin worked for TV Guide, Samson Resources and Villareal & Associates specializing in human resource management, employee relations, and consulting. Mrs. Austin holds a Bachelor of Science Degree in Political Science from Oklahoma State University and is a certified Professional in Human Resources (PHR). She is also a member of the Society for Human Resources Management, World-at-Work and Tulsa Area Human Resources Association.

Frank Capristo serves as Vice President of Turnaround & Plant Services for Matrix Service. He joined Matrix in 2013, most recently holding the position of General Manager, Maintenance & Plant Services and before that, as Project Sponsor for the BP Cherry Point Refinery where he established a strong reputation for safety and client relationship leadership. Before joining Matrix Service, he held several leadership positions at Brinderon, Jacobs Engineering and Fluor Corporation. Mr. Capristo brings more than 25 years of extensive experience in the Energy Services industry including large capital EPC projects, complex turnarounds, facility maintenance, tank maintenance and repair, industrial cleaning and fabrication. Mr. Capristo earned his Bachelor of Science in Engineering & Construction Management from Arizona State University. He also holds an Associate in Arts degree in Art History from John Cabot International College, Rome.

Vice President, Cryogenic & Storage Technologies, Ken Erdmann holds a Bachelor of Science in Aeronautical and Astronautical Engineering from Purdue University (1990) and a Masters Degree in Civil Engineering from Oklahoma State University. Ken’s engineering expertise has focused primarily in civil and structural engineering disciplines with emphasis in computer methods of structural analysis. As the first design engineer hired by Matrix PDM, Ken has over 20 years of experience with the Company. At Matrix PDM he has held positions of Design Engineer (1991-1995), Director of Engineering (1995-2011), Vice President of Engineering (2011-2016), and Vice President, Cryogenic & Storage Technologies (current). In these roles Ken has implemented new computer systems, led new product development and provided strategic planning for the company’s engineering services. In industry, Ken has served on various American Petroleum Institute (API) committees and task groups for over 15 years. Under the API Committee on Refinery Equipment, Ken has chaired the manufacturer’s and contractor’s group and was recently named Chairman of the Design Subgroup for aboveground storage tanks. Ken has 56 professional engineering licenses throughout North America and is the named inventor for various Matrix patents.

Mark Fillman
Vice President, Operations – AST & Specialty Vessels

Mark Fillman is Vice President of Operations, AST & Specialty Vessels, for Matrix Service and Matrix Applied Technologies. He joined Matrix in 1998 and has served in several roles within the storage products area throughout his career including Project Manager, Commercial Contracts Manager, Divisional Manager, and General Manager. Mr. Fillman has advanced the historical core AST business at Matrix and lead the development of the Company’s cryogenic and specialty vessel storage product and service lines. In his current role, he is responsible for the operations of EPC services and projects for aboveground storage tanks and specialty vessels. In addition, he manages the fabrication services at the Company’s Catoosa, OK facility. Mr. Fillman strives for safe, excellent execution which has led to hundreds of successfully completed projects. Mr. Fillman holds a Bachelor of Science in Civil Engineering and a Master of Science in Civil Engineering from Oklahoma State University. He is also a licensed Civil Engineer (P.E.) in the state of California.

Davis Foreman is the Vice President of Operations at Matrix NAC, overseeing the company’s infrastructure, transmission & distribution, energy, and aboveground storage tank (AST) segments. Joining Matrix in 2024 with over 28 years of experience, Mr. Foreman has honed his expertise in construction management and commissioning across fossil and nuclear power generation, as well as utility power delivery. Before Matrix, he held roles of increasing responsibility at both United E&C (including its legacy companies) and KBR, most recently serving as Senior Director of Construction and Commissioning Operations at United E&C. Mr. Foreman is a graduate of Maine Maritime Academy and holds a Bachelor of Science degree in Marine Engineering.

Melissa K. Gilliland serves as Vice President, Human Resources for Matrix Service Company. Ms. Gilliland joined Matrix Service Company in 2001 as a Human Resources Administrator and since then has served as Corporate Human Resources Manager from 2003 -2011 and Director, Human Resources from 2011 – 2019. Ms. Gilliland holds a Bachelor of Science in Business Administration and a Master of Arts in Industrial/Organizational Psychology, both from the University of Tulsa. She also holds certifications as a Professional in Human Resources (PHR) and SHRM Certified Professional (SHRM-CP). Last, Ms. Gilliland is a member of SHRM, World at Work and the Tulsa Area Human Resources Association.

John Hart is the Vice President of Business Development. Prior to this position, John served as Vice President of Business Development – Capital Services from September 2019 to September 2020. Mr. Hart joined Matrix Service in 2014 as Senior Director of Business Development where he advanced EPC and specialty vessel service areas, particularly LNG project services. Prior to joining Matrix, Mr. Hart was Vice President, Business Development for IDOM Consulting, Engineering, Architecture, S.A.U.; Vice President, Corporate Sales for The EI Group, Inc.; President of The Industrial Training Company; and President of AH&M Environmental and Pantech Inc. Mr. Hart is a former board member of the Commonwealth of Virginia’s Department of Environmental Quality and holds a Bachelor of Science degree in Civil Engineering from The Ohio State University.

Julius R. Hughes serves as Vice President of Information Technology at Matrix Service Company. Mr. Hughes brings expansive leadership experience across a diversified global business environment that includes manufacturing, supply chain, transportation, energy, and engineering and construction. Before being promoted to Vice President, Mr. Hughes served as Director of Infrastructure and Application Architecture, and before that as Director of Applications, Data Analytics, & Change Management. He is Certified by the International Information System Security Certification Consortium as an Information Systems Security Professional. Before joining Matrix, Mr. Hughes served as an Application Architect at T.D. Williamson and before that held positions at Dollar Thrifty Automotive Group and Enterprise Holdings. Mr. Hughes holds an Executive Certificate from the Kellogg Executive Education School of Management. He received his Master of Business Administration degree from Texas A&M-Commerce and his Bachelor of Business degree from Oklahoma State University. He is passionate about Diversity, Equity, and Inclusion and currently serves on the Matrix Service Company DEI Steering Committee. Externally, he also serves on the Technology and Innovation Committee for the Construction Industry Institute and on the Board for nonprofit organizations, Modus and Tulsa Boys Home.

Terry Longer is the Vice President of Operations, National Construction Group, at Matrix Service. Mr. Longer drives the development and implementation of strategic business initiatives while overseeing the overall operations and performance, ensuring the safe and successful execution of quality projects. Before joining Matrix, Mr. Longer served as Vice President of Construction for The Americas at Technip Energies, where he managed construction, subcontracts, pre-commissioning, commissioning, and start-up operations for nearly a decade. With more than 40 years of domestic and international experience in the industry, he has held leadership roles at IHI E&C International, Aker Solutions, ConocoPhillips, and Brown & Root. Mr. Longer holds a graduate degree from the Executive Construction Management program at Texas A&M University and has been an active member of the Construction Industry Institute (CII) program for many years.

Karen McDonald is Vice President, Quality & HSE, of Matrix Project Services. Prior to this role, she served as Vice President, HSE & People, for Matrix Service. Karen joined Matrix Service in 2013 as Regional Manager, Human Resources for Western Canada and, in 2015, was promoted to Director, Human Resources for Matrix Service overall. Prior to that, she worked for SNC-Lavalin, a publicly-traded, global EPC firm, in various capacities including Manager of HR and HSE and Manager of Recruitment and Training. Ms. McDonald has a Bachelor of Commerce degree from the University of Alberta and has her SHRM-SCP and CHRP certifications.

Prior to becoming President, Douglas J. Montalbano served as Senior Vice President of Operations. Mr. Montalbano joined the company in November 2014 as Vice President, Business Development. Prior to joining Matrix NAC, he served as Director, Business Development Fossil/T&D for URS Energy & Construction, Inc. Mr. Montalbano held various positions of increasing responsibility at URS Energy & Construction, Inc. and its predecessor company since 2004, including Associate General Counsel. Mr. Montalbano has a Bachelor of Science in Economics from Villanova University College of Commerce and Finance and a Juris Doctor from Villanova University School of Law. Mr. Montalbano is a licensed attorney in New York and New Jersey.

Shawn P. Payne is the President Engineering & Construction, Matrix Service Company. He previously served as President, Matrix Service Inc. Before that, he served in other leadership roles for Matrix Service including Senior Vice President, Operations, Senior Vice President of Finance and Business Services, and Vice President of Business Services. Mr. Payne joined the Company in 2012 as the Division Manager in Tucson, AZ, leading the Company’s entry into the minerals and mining business. Prior to joining Matrix, Mr. Payne held leadership roles in operations, finance, and project controls with Aker Solutions/Kvaerner, and Jacobs. Mr. Payne holds a Bachelor of Science in Business Administration, in Finance, from the University of Arizona.

Vicki R. Reese is Vice President of Financial Planning and Analysis for Matrix Service Company. Prior to her current role, Ms. Reese served as Vice President of Accounting and Finance for Matrix NAC from November 2015 to January 2022. She previously served as Business Unit Controller for Matrix Service overseeing all aspects of accounting and finance for the Storage and Specialty Vessel Division, Fabrication operations and Matrix PDM Engineering. Ms. Reese began her career with Matrix Service in 1986 and has served the company in positions of increasing responsibility, achieving a strong track record of performance and a reputation as a well-respected partner to the business. She is a Certified Public Accountant. Ms. Reese also serves on the board of Oklahoma Project Woman.

Chris Riggs joined Matrix PDM Engineering in September 2023 as Vice President, Operations and Project Delivery. He brings more than 25 years of experience in delivery, operations, project management, strategic planning, and customer service. Prior to joining Matrix PDM, Mr. Riggs worked for Wood, a GLOBAL consulting and engineering firm, for 15 years, most recently as Vice President, Project Management Office, with Responsibility for Serving Customers Worldwide. Before that, he worked with Telvent, a controls and industrial automation company specializing in SCADA, DCS and related control systems serving the oil, gas, wastewater, and power industries. Mr. Riggs holds a Bachelor of Science in Aerospace Engineering from Texas A&M University.

Justin Sheets serves as Vice President, General Counsel and Corporate Secretary. Prior to his current role, Mr. Sheets served as Vice President, Legal and Risk Management, from October 2014 to September 2019. Since joining Matrix Service Company in 2002, Mr. Sheets has served as Sr. Director, Legal and Risk Management; Director, Risk Management; and Sr. Counsel, and Consultant. Prior to Matrix Service Company, Mr. Sheets worked with Conway, McKenzie and Dunleavy in New York consulting with construction clients with a primary focus on mergers and acquisitions, restructuring and liquidations. Mr. Sheets holds a Bachelor of Science degree in Environmental Health and Safety Sciences from Indiana State University and a Juris Doctorate from the University of Tulsa. Mr. Sheets holds Construction Risk and Insurance Specialist certification and is a member of the New Jersey Bar Association, Association of Corporate Counsel and the International Risk Management Institute.

John Zwack is the Vice President of Business Development. Mr. Zwack has 30 years of experience in industrial construction and engineering, most recently as Vice President of Business Development and Marketing for CIC Group Inc. Prior to that, he served as Director of Business Development for Matrix NAC, specializing in large EPC capital and maintenance projects. He has also served as Vice President of Business Development for Pullman and held various positions within CBI’s (Chicago Bridge & Iron) Business Development and Project Management departments. Mr. Zwack holds a Bachelor of Science degree in Mechanical Engineering from Northeastern University.