(Vistage is the world’s largest CEO/business owner organization serving companies as an informal board of directors and peer review group, providing executive coaching and external feedback.)
Mr. O’Brien serves as CEO and Managing Partner of Shamrock Proppants. Mr. O’Brien started his career at Babcock and Wilcox’s Refractory Division (now Thermal Ceramics). He held the positions of Application Engineer, Foundries and Non-Ferrous Metals Market Manager, and Sales Engineer. He joined Christy Refractories Company in 1977 as a Sales Engineer. Successively he held positions of Regional Sales Manager, Vice President of Sales, Vice President of Sales and Manufacturing, and President. In 1996 Mr. O’Brien was a finalist for the Ernst and Young LLP Entrepreneur of the Year. His company, O’Brien Industrial Holdings, LLC, was listed as one of INC 5000’s fastest growing companies in the U.S. for 2007,2009, and 2015.
Vice President of Operations
Mr. Porter joined Fleischer-Seeger Construction in 1991 as a project engineer for industrial construction projects. Mr. Porter joined the Christy family In 1993 as a project manager for Christy Industrial Services. In 1997 he was transferred to Christy Minerals as plant engineer and was shortly promoted to plant manager in 1998 and Vice President of Operations in 2001.
Mr. Porter is actively involved in Vistage and is a former board member of the Mining Industry Council. In the past he has held the offices of Secretary, Vice President and President for the St. Louis section of the American Ceramic Society.
Vice President of Finance
Mr. Spellmeyer joined Shamrock Proppants in 2013 and currently serves as CFO. Prior to joining Shamrock, Mr. Spellmeyer served in various financial management roles at Emerson Electric Co., Kellwood Company, and other organizations. Mr. Spellmeyer started his career at Price Waterhouse where he advanced to the position of Manager, leading teams providing accounting, auditing and tax services.