Study results demonstrate that deep borehole disposal could be a viable option for disposing of high-level radioactive waste from advanced reactor fuel recycling

Deep Isolation Nuclear, Inc. (“Deep Isolation” or the “Company”), a leading innovator in nuclear waste disposal technology, today announced the successful completion of its work under the Advanced Research Projects Agency–Energy (ARPA E) Optimizing Nuclear Waste and Advanced Reactor Disposal Systems (ONWARDS) project titled “Enabling the Near Term Commercialization of an Electrorefining Facility to Close the Metal Fuel Cycle.” The project, led by Oklo Inc. (NYSE: OKLO), aimed to enhance key technologies supporting the recycling of used nuclear fuel through electrorefining.

Deep Isolation’s analysis confirmed that nuclear waste streams partitioned through the Argonne-baseline electrorefining process are compatible with deep borehole disposal, demonstrating a safe and practical pathway for permanent isolation. Physics-based modeling showed that high-level waste, when disposed of in Deep Isolation’s deep borehole system within generic shale and granitic host rocks, achieved long-term safety levels surpassing targets set in developing the model and achieving exposure levels that were several orders of magnitude below a stringent radiological exposure dose standard.

The results of this comprehensive initiative provide confidence that borehole disposal could serve as a viable option for high-level radioactive waste from advanced reactor fuel recycling, highlighting a potential pathway for closing the metal fuel cycle if U.S. law is changed to authorize borehole repositories for high-level waste.

“This collaboration with Oklo represents an important step forward for the advanced reactor ecosystem and our deep borehole disposal solutions for nuclear waste,” said Jesse Sloane, Executive Vice President of Engineering, Deep Isolation. “By pairing innovation in fuel recycling with advanced deep geologic disposal technology, we are helping build the technical foundation for a fully integrated, sustainable nuclear future.”

Funded through ARPA-E’s ONWARDS program, the project brought together public and private partners to accelerate the commercialization of fuel recycling technologies, strengthen safeguards, and develop pathways for waste minimization and final disposal. The outcomes support a growing industry consensus that long-term waste strategies must evolve in tandem with deployment of next-generation reactors.

About Deep Isolation

Deep Isolation is the first company to undertake development of technologies for nuclear waste disposal in deep boreholes. When commercialized Deep Isolation’s solution will offer a uniquely tailored solution to help countries identify, plan for and complete the necessary steps to dispose of their nuclear waste inventories. With 99 patents issued to date, Deep Isolation’s technology is being designed to leverage proven drilling practices to allow safe isolation of waste deep underground in horizontal, vertical, or slanted borehole repositories. Deep Isolation’s Universal Canister System was developed through a three-year project funded by the U.S. Department of Energy’s Advanced Research Projects Agency—Energy and is engineered to support integrated management of spent fuel and high-level radioactive waste from legacy and advanced reactors across storage, transportation and eventual disposal.

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For more information, visit: deepisolation.com 

Media Contact:
Sophie McCallum
media@deepisolation.com

Investor Contact:
Caldwell Bailey
InvestorRelations@deepisolation.com

Forward-Looking Statements

Statements contained in this news release that are not historical facts are “forward-looking information” or “forward-looking statements” (collectively, “forward-looking statements”) within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements include, but are not limited to, statements regarding our plans, objectives and expectations for our business, the future growth of our business and the nuclear energy and nuclear waste disposal industries as a whole, and future benefits expected to arise from our strategic partnerships. In certain cases, forward-looking statements can be identified by the use of words and phrases or variations of words and phrases or statements such as “may,” “should,” “expect,” “intend,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “will,” “could,” “project,” “target,” “potential,” “continue” and similar expressions. Forward-looking statements are based on management’s belief and assumptions, including current expectations and projections about future events and trends, and on information currently available to management.

Forward-looking statements in this or any other news release are subject to a number of risks, uncertainties, and assumptions that could cause actual results to be materially different from those expressed or implied by such forward-looking statements. Such risks, uncertainties, and assumptions are subject to a number of factors, including, among others: the failure of a market to develop for our deep borehole disposal solutions as quickly as we expect or at all; a failure of demand for our solution to develop sufficiently; regulatory and legal developments, including issues relating to obtaining regulatory approvals or permissions on the timelines we expect or at all; our lack of profitability; delays or failure in our initiative to complete a full-scale, at-depth demonstration of our Universal Canister System and our deep borehole solution; our failure to enter into contracts with customers or, once we do enter into contracts, to continue such contractual relationships or to receive new contract awards; our dependency on governmental contracts and awards; our  failure to manage our growth effectively or to execute our business plan; a failure to sustain and expand relationships with governmental entities and strategic partners; failure in the assumptions or analyses we have used in supporting forecasts or plans; our inability to commercialize our products at scale; the development or deployment of other technologies or solutions supplanting or competing with our technologies; challenges to our intellectual property; failures to protect, maintain, enforce, and enhance our intellectual property, and claims by others of intellectual property infringement; political and public perceptions of nuclear energy, including perceptions as to accidents or other high-profile events involving nuclear power facilities or radioactive materials; our liquidity and ability to raise capital; any inability to control operating and project costs and project delays or other project-related problems; security (including cybersecurity) breaches or disruptions; geopolitical, macroeconomic, domestic events or crises, including supply chain disruptions and other risks and uncertainties outside of our control; weather and effects of climate change; and litigation or legal proceedings that may be brought against us.

The foregoing is not an exhaustive list of all the factors that may cause any forward-looking statements to prove inaccurate or our actual results to differ materially from our expectations and forecasts. Moreover, we operate in a highly regulated environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties, and assumptions, the future events and trends discussed in this release may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements, and we cannot guarantee future results, performance, or achievements. Accordingly, readers should not place undue reliance on forward-looking statements. We undertake no obligation to update any forward-looking statements for any reason after the date of this release or to conform these statements to actual results or revised expectations, except as required by law.

Additional information concerning the factors above and other factors will be found in the Company’s public filings with the Securities and Exchange Commission (the “SEC”), including the sections titled “Forward-Looking Statements” and “Risk Factors” in the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 filed with the SEC on November 14, 2025, our Form S-1, originally filed August 18, 2025 and subsequently amended, and in filings with the SEC that will be made in the future. The Company’s SEC filings are available free of charge at www.sec.gov or upon written request to Deep Isolation Nuclear at InvestorRelations@deepisolation.com. 

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CEO Rod Baltzer and Executive VP of Engineering Jesse Sloane to Participate in Discussions and Presentations on Advanced Reactor Waste Management and Global Deep Borehole Disposal Developments

Deep Isolation Nuclear, Inc. (“Deep Isolation” or the “Company”), a leading innovator in nuclear waste disposal technology, will share insights on the deployment readiness of its Universal Canister System and the global advancement of deep borehole disposal technology at the 52^nd Annual Waste Management Symposia (WM2026).

The event, to be held March 8-12 in Phoenix, Arizona, brings together a global network of more than 2,500 attendees and 200 exhibitors from 900 organizations and 30 countries to drive discussion on safe, cost-effective solutions for handling radioactive materials and decommissioning nuclear facilities. This year’s theme, “Efficient and Innovative Nuclear Materials and Technology Solutions,” aligns closely with Deep Isolation’s mission to advance practical disposal options for the nuclear industry.

Deep Isolation’s CEO Rod Baltzer will participate as a panelist on Tuesday, March 10 at 1:45 p.m. MST during the session “Advanced Reactor Waste Stream Integrated Management and Disposition.” The panel will explore efforts and ideas to reduce the impact of used nuclear fuel (UNF) and other waste streams stemming from advanced reactor fuel cycles.

“I look forward to this important discussion with fellow panelists on how the industry can address waste management challenges from the earliest stages of advanced reactor development,” Baltzer said. “The expertise represented on this panel offers a valuable opportunity to explore integrated approaches between waste solutions and reactor design, an integration that is essential for the future of the nuclear industry.”

On Wednesday, March 11, Jesse Sloane, Executive Vice President of Engineering at Deep Isolation, will represent Deep Isolation in two important sessions focused on deep borehole disposal. At 8:00 a.m. MST, Sloane will participate as a panelist in the “IAEA Coordinated Research Project and the Global State of Knowledge on the Deep Borehole Disposal System.” This session will examine current global understanding and recent national motivations to further develop the deep borehole disposal concept for radioactive material. Responding to growing international interest in exploring the feasibility of deep borehole disposal, the IAEA has launched a Coordinated Research Project (CRP) to collect the current state of knowledge and draft a generic program to address further R&D requirements. The panel will focus on how a range of geological disposal concepts can complement each other to provide for national disposal needs.

Later that day at 1:15 p.m. MST, Sloane will present “Deployment Readiness of the Universal Canister System for Deep Borehole Repositories” during the session “Developments in Deep Borehole Disposal Around the World.” The presentation will explore the deployment readiness of the Universal Canister System (UCS), highlighting the objectives and requirements for demonstrating its performance in a representative deep borehole repository.

“These sessions represent critical conversations about the future of deep borehole disposal,” Sloane said. “From discussing the global state of knowledge to exploring deployment readiness, I look forward to engaging with colleagues on how we can collectively advance this critical technology in the nuclear sector.”

Deep Isolation will be located at Booth 637 at the WM2026 conference. Attendees are invited to visit the booth to learn more about the Company’s innovative solutions for nuclear waste disposal.

About Deep Isolation

Deep Isolation is the first company to undertake development of technologies for nuclear waste disposal in deep boreholes. When commercialized Deep Isolation’s solution will offer a uniquely tailored solution to help countries identify, plan for and complete the necessary steps to dispose of their nuclear waste inventories. With 91 patents issued to date, Deep Isolation’s technology is being designed to leverage proven drilling practices to allow safe isolation of waste deep underground in horizontal, vertical, or slanted borehole repositories. Deep Isolation’s Universal Canister System was developed through a three-year project funded by the U.S. Department of Energy’s Advanced Research Projects Agency—Energy and is engineered to support integrated management of spent fuel and high-level radioactive waste from legacy and advanced reactors across storage, transportation and eventual disposal.

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For more information, visit: deepisolation.com 

Media Contact:
Sophie McCallum
media@deepisolation.com

Investor Contact:
Caldwell Bailey
InvestorRelations@deepisolation.com

Forward-Looking Statements

Statements contained in this news release that are not historical facts are “forward-looking information” or “forward-looking statements” (collectively, “forward-looking statements”) within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements include, but are not limited to, statements regarding our plans, objectives and expectations for our business, the future growth of our business and the nuclear energy and nuclear waste disposal industries as a whole, and future benefits expected to arise from our strategic partnerships. In certain cases, forward-looking statements can be identified by the use of words and phrases or variations of words and phrases or statements such as “may,” “should,” “expect,” “intend,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “will,” “could,” “project,” “target,” “potential,” “continue” and similar expressions. Forward-looking statements are based on management’s belief and assumptions, including current expectations and projections about future events and trends, and on information currently available to management.

Forward-looking statements in this or any other news release are subject to a number of risks, uncertainties, and assumptions that could cause actual results to be materially different from those expressed or implied by such forward-looking statements. Such risks, uncertainties, and assumptions are subject to a number of factors, including, among others: the failure of a market to develop for our deep borehole disposal solutions as quickly as we expect or at all; a failure of demand for our solution to develop sufficiently; regulatory and legal developments, including issues relating to obtaining regulatory approvals or permissions on the timelines we expect or at all; our lack of profitability; delays or failure in our initiative to complete a full-scale, at-depth demonstration of our Universal Canister System and our deep borehole solution; our failure to enter into contracts with customers or, once we do enter into contracts, to continue such contractual relationships or to receive new contract awards; our dependency on governmental contracts and awards; our  failure to manage our growth effectively or to execute our business plan; a failure to sustain and expand relationships with governmental entities and strategic partners; failure in the assumptions or analyses we have used in supporting forecasts or plans; our inability to commercialize our products at scale; the development or deployment of other technologies or solutions supplanting or competing with our technologies; challenges to our intellectual property; failures to protect, maintain, enforce, and enhance our intellectual property, and claims by others of intellectual property infringement; political and public perceptions of nuclear energy, including perceptions as to accidents or other high-profile events involving nuclear power facilities or radioactive materials; our liquidity and ability to raise capital; any inability to control operating and project costs and project delays or other project-related problems; security (including cybersecurity) breaches or disruptions; geopolitical, macroeconomic, domestic events or crises, including supply chain disruptions and other risks and uncertainties outside of our control; weather and effects of climate change; and litigation or legal proceedings that may be brought against us.

The foregoing is not an exhaustive list of all the factors that may cause any forward-looking statements to prove inaccurate or our actual results to differ materially from our expectations and forecasts. Moreover, we operate in a highly regulated environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties, and assumptions, the future events and trends discussed in this release may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements, and we cannot guarantee future results, performance, or achievements. Accordingly, readers should not place undue reliance on forward-looking statements. We undertake no obligation to update any forward-looking statements for any reason after the date of this release or to conform these statements to actual results or revised expectations, except as required by law.

Additional information concerning the factors above and other factors will be found in the Company’s public filings with the Securities and Exchange Commission (the “SEC”), including the sections titled “Forward-Looking Statements” and “Risk Factors” in the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 filed with the SEC on November 14, 2025, our Form S-1, originally filed August 18, 2025 and subsequently amended, and in filings with the SEC that will be made in the future. The Company’s SEC filings are available free of charge at www.sec.gov or upon written request to Deep Isolation Nuclear at InvestorRelations@deepisolation.com. 

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Sunseri brings over four decades of experience in nuclear plant operations, safety, engineering, and governance as the Company advances its deep borehole demonstration program

Deep Isolation Nuclear, Inc. (“Deep Isolation” or the “Company”), a leading innovator in nuclear waste disposal technology, today announced the appointment of Matthew Sunseri to its Advisory Board as the Company advances its deep borehole demonstration program. Mr. Sunseri brings deep expertise in nuclear safety, regulatory engagement, organizational performance, and enterprise risk management to advanced nuclear and waste management initiatives.

Mr. Sunseri is a veteran nuclear energy executive and board leader with more than four decades of experience in nuclear plant operations, safety, engineering, and governance. His career has focused on leading safety-critical, highly regulated nuclear organizations, and he has a demonstrated record of strengthening safety culture, accountability, and operational excellence.

“Matt’s experience leading safety-critical nuclear organizations and advising the Nuclear Regulatory Commission brings valuable perspective to our governance as we move into full-scale demonstration operations,” says Rod Baltzer, President and CEO of Deep Isolation. “His track record of building safety culture and managing enterprise risk in highly regulated environments directly aligns with our mission to deliver a disciplined, safety-led approach to nuclear waste disposal.”

“From an operator’s perspective, long-term waste management solutions must demonstrate both technical rigor and regulatory credibility,” said Mr. Sunseri. “Deep Isolation’s borehole approach reflects serious engineering discipline, and I look forward to contributing to the governance and oversight needed as the Company advances its efforts.”

Mr. Sunseri’s appointment further strengthens Deep Isolation’s advisory infrastructure as the Company continues building momentum toward public listing and commercial deployment. His expertise in organizational risk management, regulatory strategy, and safety governance complements the leadership recently added through the appointments of Chief Financial Officer Joseph Nelson, General Counsel Paula Whitten-Doolin, and Board Director Ralph L. Hunter, collectively expanding the Company’s capacity to engage effectively with industry stakeholders and the financial community.

Mr. Sunseri has held multiple senior leadership roles across the U.S. nuclear industry, including as President and Chief Executive Officer of Wolf Creek Nuclear Operating Corporation, where he led one of the nation’s top-performing nuclear facilities with a strong focus on operational excellence and regulatory compliance. He has also contributed extensively to nuclear safety oversight and policy through his service on the U.S. Nuclear Regulatory Commission’s Advisory Committee on Reactor Safeguards (ACRS). He currently serves as Chair of the Advisory Council for the Nuclear Engineering Department at Texas A&M University, supporting the development of the next generation of nuclear engineers. Mr. Sunseri has represented the nuclear sector in international climate discussions, including participation at COP27, where nuclear energy’s role in decarbonization and energy security was a focus. A registered Professional Engineer and an American Nuclear Society Fellow, Mr. Sunseri is widely recognized for his expertise in nuclear operations, safety culture, and industry governance.

About Deep Isolation

Deep Isolation is the first company to undertake development of technologies for nuclear waste disposal in deep boreholes. When commercialized Deep Isolation’s solution will offer a uniquely tailored solution to help countries identify, plan for and complete the necessary steps to dispose of their nuclear waste inventories. With 91 patents issued to date, Deep Isolation’s technology is being designed to leverage proven drilling practices to allow safe isolation of waste deep underground in horizontal, vertical, or slanted borehole repositories. Deep Isolation’s Universal Canister System was developed through a three-year project funded by the U.S. Department of Energy’s Advanced Research Projects Agency—Energy and is engineered to support integrated management of spent fuel and high-level waste from advanced reactors across storage, transportation and eventual disposal.

###

For more information, visit: deepisolation.com 

Media Contact:
Sophie McCallum
media@deepisolation.com

Investor Contact:
Caldwell Bailey
InvestorRelations@deepisolation.com

Forward-Looking Statements

Statements contained in this news release that are not historical facts are “forward-looking information” or “forward-looking statements” (collectively, “forward-looking statements”) within the meaning of Section 27A of the Securities Act and Section 21E of the Securities Exchange Act of 1934, as amended. Forward-looking statements include, but are not limited to, statements regarding our plans, objectives and expectations for our business, the future growth of our business and the nuclear energy and nuclear waste disposal industries as a whole, and future benefits expected to arise from our strategic partnerships. In certain cases, forward-looking statements can be identified by the use of words and phrases or variations of words and phrases or statements such as “may,” “should,” “expect,” “intend,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “will,” “could,” “project,” “target,” “potential,” “continue” and similar expressions. Forward-looking statements are based on management’s belief and assumptions, including current expectations and projections about future events and trends, and on information currently available to management.

Forward-looking statements in this or any other news release are subject to a number of risks, uncertainties, and assumptions that could cause actual results to be materially different from those expressed or implied by such forward-looking statements. Such risks, uncertainties, and assumptions are subject to a number of factors, including, among others: the failure of a market to develop for our deep borehole disposal solutions as quickly as we expect or at all; a failure of demand for our solution to develop sufficiently; regulatory and legal developments, including issues relating to obtaining regulatory approvals or permissions on the timelines we expect or at all; our lack of profitability; delays or failure in our initiative to complete a full-scale, at-depth demonstration of our Universal Canister System and our deep borehole solution; our failure to enter into contracts with customers or, once we do enter into contracts, to continue such contractual relationships or to receive new contract awards; our dependency on governmental contracts and awards; our failure to manage our growth effectively or to execute our business plan; a failure to sustain and expand relationships with governmental entities and strategic partners; failure in the assumptions or analyses we have used in supporting forecasts or plans; our inability to commercialize our products at scale; the development or deployment of other technologies or solutions supplanting or competing with our technologies; challenges to our intellectual property; failures to protect, maintain, enforce, and enhance our intellectual property, and claims by others of intellectual property infringement; political and public perceptions of nuclear energy, including perceptions as to accidents or other high-profile events involving nuclear power facilities or radioactive materials; our liquidity and ability to raise capital; any inability to control operating and project costs and project delays or other project-related problems; security (including cybersecurity) breaches or disruptions; geopolitical, macroeconomic, domestic events or crises, including supply chain disruptions and other risks and uncertainties outside of our control; weather and effects of climate change; and litigation or legal proceedings that may be brought against us.

The foregoing is not an exhaustive list of all the factors that may cause any forward-looking statements to prove inaccurate or our actual results to differ materially from our expectations and forecasts. Moreover, we operate in a highly regulated environment. New risks emerge from time to time. It is not possible for our management to predict all risks, nor can we assess the impact of all factors on our business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements we may make. In light of these risks, uncertainties, and assumptions, the future events and trends discussed in this release may not occur and actual results could differ materially and adversely from those anticipated or implied in the forward-looking statements, and we cannot guarantee future results, performance, or achievements. Accordingly, readers should not place undue reliance on forward-looking statements. We undertake no obligation to update any forward-looking statements for any reason after the date of this release or to conform these statements to actual results or revised expectations, except as required by law.

Additional information concerning the factors above and other factors will be found in the Company’s public filings with the Securities and Exchange Commission (the “SEC”), including the sections titled “Forward-Looking Statements” and “Risk Factors” in the Company’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2025 filed with the SEC on November 14, 2025 and in filings with the SEC that will be made. The Company’s SEC filings are available free of charge at www.sec.gov filed or upon written request to Deep Isolation Nuclear at InvestorRelations@deepisolation.com. 

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