Heritage-Crystal Clean, Inc. Welcomes Mary Pat Thompson to its Board of Directors

July 28, 2022

ELGIN, IL, July 28, 2022 — Heritage-Crystal Clean, Inc. (NASDAQ: HCCI), a leading provider of parts cleaning, used oil re-refining, and hazardous and non-hazardous waste services, announced today the addition of Mary Pat Thompson to its Board of Directors.

“We are excited to welcome Mary Pat to Heritage-Crystal Clean’s Board of Directors, “said Heritage-Crystal Clean President & CEO Brian Recatto. “Ms. Thompson comes to Heritage-Crystal Clean with over 30 years experience in accounting and advisory leadership roles. She currently serves as a director on both public and private company boards and will be an asset to the company as we push forward with our growth and ESG strategy. Mary Pat will also join our audit committee. Having a group of diverse voices at the leadership table is increasingly important as we work to reach our full potential as a leading environmental services company.”

Ms. Thompson is currently serving as a board and audit committee member for H&E Equipment based out of Baton Rouge. Ms. Thompson has previously served as Chief Financial Officer and Treasurer of Taronis Fuels, Inc. (“Taronis”), a renewable fuel and power generation company, and has served as a consultant at Bruckmann, Rosser, Sherrill & Co., a private equity firm, since 2019.

“I feel fortunate to join the board of Heritage-Crystal Clean at such an exciting time for the company,” Mary Pat shared. “Heritage-Crystal Clean is growing its top and bottom line and is well positioned to not only provide a valuable product and service but in the process help its customer generate meaningful progress with their ESG initiatives.”

Ms. Thompson graduated Summa Cum Laude from the University of Idaho with a B.S. in accounting and is a licensed Certified Public Accountant in Idaho. Ms. Thompson previously served as Senior Vice President of Finance and Administration and Chief Financial Officer of MWI Animal Health from August 2005 through her retirement in October 2018, with oversight of finance, inventory management, information technology, and human resources. Ms. Thompson also served as Vice President, Secretary and Chief Financial Officer of MWI Animal Health from June 2002 to August 2005. Since 2015, she has served on Zion’s Bank Business Advisory Board and the San Francisco Reserve’s 12th District Economic Advisory Council, where she was Chairperson for 2019.