Our Purpose
Safety First
At Apex Energy, safety is our utmost priority. We adhere to stringent protocols to ensure the well-being of our team, environment, and community while carrying out our operations.
Community Focused
Our commitment extends to the communities we operate in. We strive to contribute positively to local initiatives, ensuring our presence benefits those around us.
Operational Excellence
We aim for operational excellence by leveraging our technical expertise to maximize efficiency and reduce environmental impact throughout our operations in the Appalachia Basin.
Sustainable Practices
Apex Energy prioritizes sustainable practices, integrating innovative technologies and methods that support environmental conservation while promoting energy production.
Empowering Growth
We believe in empowering growth not only within our company but also among the local workforce by providing training and development opportunities.
Meet Our Team
Our team at Apex Energy is composed of experienced professionals dedicated to ensuring safe and efficient operations. Get to know the passionate individuals driving our success.
Mark Rothenberg
CEO
Mark Rothenberg is founder of Apex Energy, LLC. Prior to starting Apex, he was an executive in the EXCO-BG Appalachia Joint Venture and before that he was part of the team at Vantage Energy. His career spans over 30 years of operations and reservoir engineering, as well as business development and executive management in some of the most prolific oil and gas basins throughout the United States. Mark started his career as an engineer with Amoco and progressed into leadership positions at mid-sized public companies and small private companies. He has specialized in unconventional resources and has successfully applied cutting edge technological advances in drilling and completion techniques to these projects. His experience includes exploration and exploitation of shale plays, coalbed methane reservoirs, and tight gas sands. Mark emphasizes a combination of strong subsurface understandings with industry leading practices to successfully develop these unconventional assets. Mark has a degree in chemical engineering from the University of Colorado.
Rich Mangene
CAO / VP of Finance
Rich Mangene is the Chief Accounting Officer and VP of Finance for Apex Energy. Since joining the company in 2014, his primary responsibilities have been the company’s accounting and reporting, treasury management, budgeting, credit facility management, and gas hedging/marketing. Rich has 25 years of accounting and finance experience in public and privately held companies. His career began at KPMG where he advised domestic and worldwide companies on various SEC filings, public and private debt offerings and the initial implementation of the Sarbanes-Oxley Act. He then spent several years overseeing the accounting and finance of Alcoa’s global rolled products business where his work also included due diligence on mergers and acquisitions. Rich then spent two years as the Corporate Controller for Dynavox Inc. where he was responsible for technical accounting, SEC reporting and Financial Planning and Analysis. Rich is a graduate of Duquesne University with a Bachelor of Science and Business Administration – Accounting and a Certified Public Accountant in Pennsylvania.
Eric Shullenberger
VP of Exploration
Eric Shullenberger serves as the VP of Exploration for Apex and is a geologist by background. Eric’s career in oil and gas spans 18 years and includes a wide variety of projects, both international and domestic, including shallow water Gulf of Mexico, international heavy oil reservoirs and many US Shale Basins. He has focused the last 14 years on exploring, appraising, and developing US Onshore unconventional plays. Before joining Apex in 2017, Eric served as a geologist and project lead at Anadarko Petroleum Corporation and as a geologist at the Chevron Corporation. His experience includes hands-on operations and development, exploration, project management, A&D evaluation, and team leadership. Eric is a degreed geologist and holds a B.S. in Geology from Miami University and a M.S. in Geology from the University of Wisconsin—Madison. Eric is a long-time member of the American Association of Petroleum Geologists.
Minh Nguyen
VP of Operations
Minh Nguyen has worked with Apex Energy in various capacities since 2018. He has over 26 years of drilling and operations experience with a main focus on unconventional plays. Minh started his career in the Gulf of Mexico and international markets. He then translated his knowledge base to onshore drilling at Mitchell Energy in 2000. He has mentored drilling engineers and led integral projects at EnCana and Range Resources. Minh spent about 9 years at Range establishing and improving processes which helped lead to the drilling successes at Range in their core and expansion areas in both Texas and Pennsylvania. Minh also consulted for a number of private, independent oil & gas companies helping to successfully develop their unconventional reservoirs. Minh is a long time member of the Appalachian Basin AADE and served as their Program Committee Chair, 2010-2019. He is also a long time member of SPE. Minh has a Bachelor of Science degree in Petroleum Engineering from The University of Texas at Austin.
Dominik Wells
VP of Engineering
Dominik Wells is the Vice President of Engineering at Apex Energy, bringing over 20 years of reservoir engineering expertise with a focus on unconventional shale formations across multiple U.S. basins. His career includes leadership roles at Brigham Exploration, PDC Energy, and Talisman Energy/Repsol, where he successfully led multidisciplinary teams to improve well performance, manage complex field development projects, and oversee acquisition and divestiture evaluations. Dominik is skilled in delivering SEC- and PRMS-compliant reserves reporting, supporting strategic business growth and operational excellence. Known for his technical proficiency and breadth of knowledge, he is committed to maximizing value and efficiency throughout the upstream oil and gas lifecycle. Dominik holds a degree in Materials Science & Engineering from Carnegie Mellon University in Pittsburgh, PA.
Lars Inman
VP of Riverbend Asset
Lars Inman is Apex Energy's VP of the Riverbend Asset. Prior to joining Apex, Lars co-founded and was managing partner of Jackson Run Energy Partners, focused on Marcellus and Utica development in the tri-state area. Prior to that, Lars served as Director of Geology for Antero Resources and managed all aspects of geologic operations and regulatory affairs for Antero’s Marcellus Shale and Utica Shale horizontal well development programs in both Ohio and West Virginia including the drilling of over 250 wells. Prior to Antero, he served as Operations Geologist at Williams and was directly responsible for drilling over 400 tight gas sand wells on the western slope of Colorado in the Piceance Basin. He has 28 years of industry experience including operations work in domestic unconventional development projects and international geologic modeling and resource assessments. He has worked Appalachian Basin projects for over 17 years in many capacities ranging from surface and subsurface operations to expert testimony and Ohio and West Virginia regulatory down-spacing efforts. Lars is skilled in oil and gas field development strategies and water resource management and planning. He received his degree from the University of Pennsylvania in Geology and Environmental Science.
Andrew Lewis
VP of Land
Andrew Lewis is Apex Energy’s VP of Land, bringing
with him over 17 years of experience in land management, acquisitions,
divestitures, and contract negotiations within the Appalachian Basin.
He began his career in 2008 as a landman working the Marcellus in
Pennsylvania and later the Utica in Ohio on behalf of Chesapeake
Energy. Prior to joining Apex, Andrew directed land operations at
Olympus Energy, scaling their department as they transitioned from
land aggregation to successful operator of over 100 unconventional
wells. His background in working with multiple departments has enabled
him to align strategy with operational objectives by focusing on clear
communication. Andrew holds a BA in History from the University of
Pittsburgh, is a Certified Professional Landman through the AAPL and
is a member of the Michael Late Benedum Chapter.