“We built a different kind of firm by hiring talented professionals
who are also extraordinary people our clients love working with.”
– Jeff & Marianne

Nexus Leadership

Jeff Herzog, P.E.

Jeff Herzog, P.E.

President
Founding Partner

Jeff Herzog is the President and co-founder of Nexus Engineering Group, LLC. He is a graduate of Case Western Reserve University with degrees in Mechanical Engineering and an MBA from the Weatherhead School of Business. Jeff has 40 years of engineering and leadership experience in owner side & consulting businesses.

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Marianne Corrao, Executive Vice President and Founding Partner

Marianne Corrao

Executive Vice President
Founding Partner

Marianne Corrao is Executive Vice President and co-founder of Nexus Engineering Group, LLC, She is a graduate of Cleveland State University with a bachelor’s degree in Chemical Engineering. Marianne has more than 35 years of client-side and engineering firm experience.

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Jeff Herzog, P.E.

Jeff Herzog, P.E.

President
Founding Partner

Jeff Herzog is the President and co-founder of Nexus Engineering Group, LLC. He is a graduate of Case Western Reserve University with degrees in Mechanical Engineering and an MBA from the Weatherhead School of Business. Jeff has 40 years of engineering and leadership experience in owner side & consulting businesses.

Jeff began his career with The Standard Oil Company, which was later acquired by BP. His first assignment was as a refinery project engineer in Lima, Ohio. He had various engineering and business assignments at Sohio, and then BP (BP fully acquired Sohio in 1986). In 1991, Jeff joined a Cleveland-based engineering consulting firm leading the company’s refining business. Under his leadership, the company’s annual sales and breadth of customers grew tenfold. In 1998, Jeff joined Praxair, Inc., an industrial gas company. As part of Praxair’s business team, Jeff led the strategic planning effort and was a key member of the Houston based management team, which significantly expanded profitable hydrogen sales to the refining market.

In 2005, Jeff and his business partner Marianne Corrao formed Nexus Engineering Group, LLC. Jeff has served as the President of the Case Alumni Association which supports the Case Western University’s Schools of Engineering and Applied Sciences. Jeff, born and raised in Lima, Ohio, is married to Lynne, with whom he has three daughters and three grandchildren. He is an avid biker, runner, and sailor.

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Marianne Corrao, Executive Vice President and Founding Partner

Marianne Corrao

Executive Vice President
Founding Partner

Marianne Corrao is Executive Vice President and co-founder of Nexus Engineering Group, LLC, She is a graduate of Cleveland State University with a bachelor’s degree in Chemical Engineering. Marianne has more than 35 years of client-side and engineering firm experience.

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Marianne Corrao, Executive Vice President and Founding Partner

Marianne Corrao

Executive Vice President
Founding Partner

Marianne Corrao is Executive Vice President and co-founder of Nexus Engineering Group, LLC, She is a graduate of Cleveland State University with a bachelor’s degree in Chemical Engineering. Marianne has more than 35 years of client-side and engineering firm experience.

Marianne started her career in 1987 as a process engineer for the Standard Oil Company, Lima Refinery, where she provided technical service and conceptual engineering and design improvements for capital and maintenance projects. Later, she became a commercial planner and linear program specialist focusing on crude selection, product scheduling and capital project economics and budgeting. In 1995, Marianne joined a Cleveland-based engineering firm to focus on projects from the engineering side of project delivery. Here she was senior process engineer, project manager, and project director during her tenure. She had P&L responsibilities for engineering services approaching $10 million annually at major refineries and petrochemical plants such as BP, Amoco Oil, Marathon, Valero and others. Marianne moved to Houston, TX in 2002 to lead business development activities for Praxair, Inc. Here she developed a business strategy, technical feasibility study, risk assessment and economic evaluation for the successful design and installation of the world’s first high-purity hydrogen storage cavern. In this role, she also developed analysis tools and methods to support customers’ needs to benchmark their utility balances and understand the impact of fuel and hydrogen management on their internal energy performance.

In 2005, she joined her colleague Jeff Herzog and formed Nexus Engineering Group, LLC. She is blessed to be the daughter of Anthony and Joanne Corrao.

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Jeff Herzog, P.E.

Jeff Herzog, P.E.

President
Founding Partner

Jeff Herzog is the President and co-founder of Nexus Engineering Group, LLC. He is a graduate of Case Western Reserve University with degrees in Mechanical Engineering and an MBA from the Weatherhead School of Business. Jeff has 40 years of engineering and leadership experience in owner side & consulting businesses.

Read Jeff’s full bio >

Neal Curran

Chief Operating Officer

Neal Curran joined Nexus as Chief Operating Officer in 2006. He is responsible for leading the innovation and technology agenda at Nexus, as well as overseeing day to day operations for the firm. Neal earned his bachelor’s degree in mechanical engineering from Cleveland State University.

Emily Gambill

Emily Gambill

Director, Marketing & Strategy

Joining the firm in 2018, Emily Gambill is the Director of Marketing & Strategy responsible for leading the development and execution of Nexus’s strategic business plan. She has a bachelor’s degree in marketing and business economics from Miami University and an MBA from Northwestern’s Kellogg School of Management.

Nexus Chief Engineer Don Huller

Don Huller

Senior Advisor 

Don Huller is a Senior Advisor for Nexus, joining the firm in 2013. He is responsible for providing technical management and engineering leadership for clients in the refining, chemical, energy, and manufacturing industries. Don earned a bachelor’s degree in chemical engineering from Cleveland State University and has more than 35 years of design industry experience.

Melena Heller, Senior Director of Project Management

Melena Huller, PMP

Senior Director,
Project Management

Melena Huller is the Senior Director of Project Management. She joined the firm in 2013 and helped build Nexus’s word-class project management team and culture of close collaboration and facilitation between the project and engineering teams. She earned her bachelor’s degree in mechanical engineering from Cleveland State University and has nearly 35 years of technical and project management experience.

Lisa Theis

Lisa Theis

Human Resource Director

Lisa Theis joined Nexus in 2018 and is the Human Resources Director. She is responsible for developing the firm’s human resources strategy and overseeing the HR team tasked with benefits administration, payroll, hiring, onboarding, and talent development. She brings with her more than 20 years of hands-on human resource management experience.

Paul Morreale

Financial Controller

Paul Morreale joined Nexus in 2022. He is responsible for maintaining the financial wellness and integrity of Nexus with clients, suppliers, and banking institutions and delivering the financial analysis needed for making business critical decisions. He has over 25 years of experience in accounting, business administration, and project management.