Executive Leadership

Liz Muller

Co-Founder & CEO, Board Chair

As Co-Founder and CEO of Deep Fission, Liz Muller leads the development and commercialization of a first-of-its-kind underground nuclear energy system designed to radically reduce the cost, timeline, and siting risk of nuclear deployment. She brings decades of experience operating at the intersection of nuclear engineering, environmental stewardship, and large-scale infrastructure innovation.

Liz is a serial nuclear entrepreneur with a track record of building organizations that move technically complex, highly regulated energy solutions from concept to reality. She previously co-founded Deep Isolation, a pioneering nuclear waste disposal company, where she served as CEO and now serves as Board Chair. Under her leadership, Deep Isolation advanced deep borehole disposal from theory to regulator-engaged, commercially viable pathways, reshaping global conversations around long-term nuclear waste management.

In parallel, Liz co-founded Berkeley Earth, a nonprofit that produces authoritative climate and temperature datasets used by governments, researchers, and international organizations worldwide. Her work across these ventures reflects a consistent focus on high-consequence systems, public trust, and evidence-based decision-making in energy and environmental policy.

A named inventor on multiple patents, Liz has been recognized for her contributions to clean energy innovation, including being named a Clean Energy Rising Star by Business Insider. Her leadership is distinguished by the ability to translate deep technical insight into credible, scalable business outcomes in some of the most scrutinized regulatory environments in the world.

Liz holds a Bachelor of Mathematics from UC San Diego and a Master’s in International Management from ESCP Business School in Paris.

Rich Muller, Ph.D.

Co-Founder & CTO

Rich is co-founder and CTO of Deep Fission, and co-founder of Deep Isolation, a nuclear waste disposal company. He is also a Professor Emeritus of Physics at the University of California, Berkeley. A prolific inventor with over 80 issued patents, Rich has authored more than 100 peer-reviewed scientific articles, including key work on the safety of deeply buried nuclear waste.

His groundbreaking research has earned him numerous awards, including the MacArthur “Genius” Prize, the National Science Foundation’s Alan T. Waterman Award, and the Breakthrough Prize. He is also a member of the American Academy of Arts and Sciences. In addition to his research, Rich has received multiple teaching awards and written ten books, including Physics for Future Presidents and Energy for Future Presidents. He was recognized as one of Time’s  “People Who Mattered” in 2011.

Rich holds a B.A. in Physics from Columbia University and a Ph.D. in Physics from UC Berkeley. He also served as a national security advisor to the U.S. government for over three decades.

Mark Schmitz

Chief Financial Officer

As Chief Financial Officer at Deep Fission, William Mark Schmitz brings more than 40 years of financial leadership across energy technology, manufacturing, automotive, life safety, and capital-intensive industries. He has led global finance organizations through periods of rapid growth, operational transformation, and public company reporting, with direct responsibility for scaling complex enterprises across multiple international markets.

Mark has served as CFO of several major organizations, including Goodyear, Itron, Plug Power, and Alghanim Industries, holding leadership roles across North America, China, Brazil, the United Kingdom, and the Middle East. His experience includes scaling a company from approximately $2 billion to more than $6 billion in revenue and leading the turnaround of a financially distressed enterprise into a stable and growing multinational business. These roles required disciplined financial stewardship, capital markets expertise, and the ability to align operational strategy with long-term shareholder value.

Throughout his career, Mark has focused on preparing growth-oriented companies for the demands of public company reporting and investor scrutiny. His background spans financial leadership in startups, high-growth environments, and complex global operations, reinforcing his ability to build robust accounting systems, strengthen governance frameworks, and support capital formation strategies. He brings a steady, execution-oriented approach to financial oversight in industries where regulatory compliance and capital efficiency are critical.

Mark holds undergraduate and MBA degrees from The Ohio State University. His work at Deep Fission supports the company’s financial strategy, operational scalability, and readiness for public markets as it advances next-generation nuclear energy solutions.

Michael Brasel

Chief Operating Officer

Mike Brasel is a seasoned leader in the nuclear industry with nearly three decades of experience spanning nuclear, fossil, and renewable energy sectors. Before his role as Chief Operating Officer, Mike served as Vice President of Nuclear Programs and has already been instrumental in building Deep Fission’s engineering organization, advancing the company’s technology toward demonstration and eventual commercialization. A seasoned leader with nearly three decades of experience across the nuclear, fossil, and renewable energy sectors, he brings deep expertise in strategic planning, project management, regulatory compliance, and supply chain development.

Prior to joining Deep Fission, Mike held key leadership roles at NuScale Power, where he managed multi-billion-dollar nuclear projects, led supply chain development for first-of-a-kind nuclear technologies, and directed regulatory affairs. Most recently, he served as Senior Project Director for the Carbon Free Power Project, overseeing reactor pressure vessel manufacturing, licensing applications, and large-scale capital project planning.

Mike’s career also includes leadership positions at Dairyland Power Cooperative, where he served as Plant Manager of the La Crosse Boiling Water Reactor, directing decommissioning efforts and nuclear regulatory compliance. His background as a U.S. Navy Nuclear Plant Operator further solidifies his expertise in reactor operations and maintenance.

Beyond his corporate roles, Mike is actively involved in industry leadership, serving on multiple Boards of Directors, including Great River Energy and Lake Region Electric Cooperative. He holds an M.B.A. from the University of Wisconsin-La Crosse, a B.S. in Mechanical Engineering Technology from Old Dominion University, and has completed executive education at Kellogg School of Business, Northwestern University.

Mark Pérès

Chief Nuclear Officer

Mark is dedicated to the advancement of nuclear energy as part of the global solution to improve human quality of life and reduce harm to the planet caused by pollution.

He has over forty years of experience in the nuclear industry including design, construction, commissioning, engineering, operations, cleanup, and decommissioning. Mark has held key engineering and project management leadership roles at Kairos Power, NuScale Power, Fluor, Los Alamos, and the US DOE’s Hanford K Basins Spent Nuclear Fuel and Liquid Waste Treatment facilities. Mark started his career as a Reactor Operator at the Fast Flux Test Facility, a 400 MWt sodium cooled fast spectrum reactor.

Mark received his undergraduate degree in mechanical engineering from Montana State University, a aster’s degree in mechanical engineering from Washington State University, and is a Ph.D. candidate (ABD) in nuclear engineering at the University of South Carolina, where he also serves as an adjunct professor. He is a registered professional engineer in the state of Washington and a certified Project Management Professional.

Stacy Tarver Patterson

Chief Marketing Officer

As Chief Marketing Officer at Deep Fission, Stacy Tarver Patterson leads narrative strategy, market positioning, and go-to-market development for advanced nuclear energy deployment. Her work focuses on translating complex technical innovation into credible storytelling that resonates with investors, industry, and the broader public.

Stacy brings 19 years of experience across global marketing strategy, digital product growth, and brand transformation for technology and consumer platforms. Her career includes leadership roles with organizations such as Nike, Code and Theory, and West Ventures, where she built and directed large cross-functional teams spanning digital marketing, commerce, product storytelling, and consumer insight. At Nike, she helped shape global key-city and digital transformation strategy and led a 65-person team overseeing digital marketing across Greater China, supporting a multi-billion-dollar regional business.

She also brings a founder perspective through her work as Managing Director of a venture studio, co-founder of a venture-backed digital health startup, and founding principal of New Math, a research and strategy practice that connects academic insight with industry application to accelerate emerging technologies.

Stacy serves as CMO-in-Residence at Columbia Startup Lab and collaborates with Columbia University’s Lab for Intergroup Relations and the Social Mind, studying the intersection of culture, identity, and digital behavior. She holds an MBA and has spoken at global industry forums including Cannes Lions International Festival of Creativity and South by Southwest (SXSW).

Jon Gordon

General Counsel

Jon Gordon oversees legal, compliance, securities, and public company reporting at Deep Fission. He brings more than twenty years of experience guiding energy and industrial companies through complex transactions and regulatory landscapes.

Before joining Deep Fission, Jon served as General Counsel and Chief Commercial Officer of a company developing small modular hydrogen electrolyzers, and earlier co-founded Universal Hydrogen, a pioneer in hydrogen-powered regional aircraft and fueling systems. Earlier in his career, he was Deputy General Counsel for Technology and Digital at United Technologies (now Raytheon Technologies) and Senior Counsel for private investments at Two Sigma. He began his career practicing mergers and acquisitions and securities law at Cravath, Swaine & Moore and Wachtell, Lipton, Rosen & Katz.

Jon has advised on numerous precedent-setting energy transactions, including Berkshire Hathaway Energy’s development and financing of the Alta Wind and Antelope Valley Solar projects and Consol Energy’s acquisition of Dominion’s Appalachian Marcellus Shale E&P business and take-private acquisition of CNX Gas Corporation. He also led the creation and initial public offering of an innovative bank acquisition vehicle designed to recapitalize and acquire distressed financial institutions during the housing crisis.

Jon earned both his B.A. and J.D. from the University of Chicago.