Deep Isolation awarded contract to study deep borehole disposal in Slovenia

LONDON — Deep Isolation, a leading innovator in spent nuclear fuel and high-level nuclear waste storage and disposal solutions, announced a new contract to conduct a borehole feasibility study for ARAO, Slovenia’s radioactive waste management organization.

The study will examine whether a deep borehole repository could dispose of spent fuel from Slovenia’s TRIGA II research reactor at the Josef Stefan Institute in Ljubljana. The 1960s-era reactor, one of 66 of its kind worldwide, produces radioactive isotopes for medical research and for training. It is scheduled to be shut down in 2043.

“We are very interested in the potential for deep boreholes to provide a safe disposal solution for Slovenia’s spent nuclear fuel at a lower cost than in a mined repository,” said Leon Kegel, ARAO Head of Planning and Development.  “We are already studying this at the Krško nuclear plant as part of a separate project with Deep Isolation and other ERDO members. The TRIGA II project gives ARAO the opportunity to evaluate the potential for Slovenia’s research reactor fuel.”

Deep Isolation’s deep borehole disposal (DBD) solution combines established directional drilling techniques with patented technologies and processes that can be deployed in many geologies. The study will evaluate data about the reactor’s spent fuel; provide cost estimates for a borehole in granite and shale; and provide a timeline.

Deep Isolation has completed other feasibility studies for advanced nuclear projects, including for EPRI (U.S.) and Fermi Energia (Estonia). “Research reactor fuel is an interesting market for Deep Isolation, and waste disposal is still an unsolved problem,” said Chris Parker, Managing Director of Deep Isolation EMEA Ltd. “More countries have research reactors than full-scale power plants. Slovenia is an early adopter in this market, and we expect that the work will show that DBD is a cost-effective solution.”

In recent years, Deep Isolation has established itself as offering a credible and innovative solution that is increasingly being considered an alternative to (or complementary with) traditional mined repositories. The company is now in conversations with multiple countries on three continents about its DBD option.

Slovenia's TRIGA Reactor Platform
Slovenia’s TRIGA Reactor Platform

About Deep Isolation
Berkeley, CA-based Deep Isolation is a leading innovator in nuclear waste storage and disposal. Founded through a passion for environmental stewardship, scientific ingenuity, and entrepreneurship, Deep Isolation has developed a patented solution using directional drilling and inclusive community engagement to safely isolate nuclear waste deep underground.

Press Contacts

Kari Hulac — Deep Isolation

Deep Isolation, Inc.
2001 Addison St, Ste. 300
Berkeley, CA 94704

Blog by Kari Hulac, July 28, 2021

Deep Borehole Expert Joins Deep Isolation

Deep Isolation is pleased to welcome its newest team member: Ethan Bates, Director of Systems Engineering.

Dr. Bates, a nuclear engineer who received his doctorate from MIT in 2015, is an expert in reactor safety and nuclear systems integration and has worked for more than five years with leading advanced nuclear companies. In 2014 he co-authored a short paper for the Energy Policy journal published by Elsevier titled “Can Deep Boreholes Solve America’s Nuclear Waste Problem?” The highly cited paper looked at how disposal in deep boreholes could ease siting issues, provide modularity, and lower costs.

At Deep Isolation Dr. Bates is responsible for systems engineering-based product development for the operations of the company’s deep borehole repository concept.

In this Q&A get to know Dr. Bates and learn about his passion for deep boreholes.

Q. What inspired you to choose nuclear engineering as your career path?

After growing up in Singapore and participating in Model United Nations in high school, I became familiar with international issues needing massive institutional and technological advancements. The one that concerned me the most and which I felt could benefit the most from my quantitative skills was climate change.  I applied to Massachusetts Institute of Technology (MIT) and was admitted along with my twin brother Richard, who shares my passion for preventing climate change. We saw a flyer for a new freshman class called “Energy, Environment, and Society” and were intrigued by its project-based format.  I chose a project analyzing ways to recover thermal energy from MIT’s 5 -megawatt research reactor and became increasingly fascinated by how elegant, clean, efficient, and compact nuclear reactors are.  Combined with the realization that nuclear power was one of — if not the only — mature clean energy technology that could be expanded rapidly to grid-scale, I dedicated my studies and career to advancing the technology.

Dr. Ethan Bates touring SKB’s Äspö Hard Rock Laboratory (HRL), a spent fuel repository demonstration facility near Oskarshamn, Sweden.
Dr. Ethan Bates touring SKB’s Äspö Hard Rock Laboratory (HRL), a spent fuel repository demonstration facility near Oskarshamn, Sweden. He is standing next to a display model of a KBS-3 repository concept copper canister, designed to corrode less than 1 mm in 100,000 years.

Q. After earning your nuclear science and engineering degree from MIT, you earned your doctorate there in which you developed a computational thermal and geologic model to simulate and optimize the design for a deep borehole waste disposal/spent nuclear fuel repository. Tell us how you became interested in deep boreholes and share some highlights of your doctoral research.

I saw an intriguing handwritten and photocopied flyer in the nuclear engineering department asking for an undergraduate researcher to conduct experiments on new concepts of emplacing nuclear waste in a deep borehole repository.  I discovered the flyer was composed by Professor Michael Driscoll, who had been pioneering borehole research (among other areas) for decades and had developed a reputation for tackling highly complex problems with elegant solutions he derived with pencil and paper.  This seemed like a great way to get more hands-on experience in a laboratory and to contribute to solving the nuclear waste problem.  Inspired by my advisors (Prof. Michael Driscoll and Prof. Jacopo Buongiorno), I made the research the focus of my bachelor’s and master’s degrees, which received an award from the Department of Energy in 2011 and led to a scholarship from the American Nuclear Society in 2013.

My doctoral research led to a published paper on sealing materials for borehole repositories.  I also investigated new filler materials for the canister and canister-to-borehole wall gap.  I realized that to quantify the benefit of these advancements, I’d need to develop an integrated safety and cost model.  This allowed me to provide justified answers to even more fundamental and unexplored questions of deep borehole design, such as the limits of waste loading and borehole spacing.

One of my favorite experiences was collaborating with accomplished scientists from national laboratories and having the chance to visit the Waste Isolation Pilot Plant in Carlsbad, New Mexico.  It gave me a true sense of geologic time scales and proved to me that siting, building, and operating a deep borehole repository is possible.

A key finding of my research validated my initial draw to nuclear as a compact and efficient energy source.  I estimated that for the same amount of electricity, geologic disposal of nuclear waste will require up to 10,000 times less land area compared to the alternative of building advanced natural gas plants with carbon capture and sequestration into similarly isolated geologic formations.

Q. You also published a short paper examining whether deep boreholes could provide a means to address the nuclear waste problem. What did this paper conclude?

The primary conclusion is that deep boreholes provide access to stable rocks that have

been isolated from flowing groundwater and surface processes for millions of years.  This increases the number of potential sites where geologic disposal is possible, easing one of the biggest challenges to the nuclear industry.  The concept relies more on the natural barriers and features whose behavior can be extrapolated into the future more confidently compared to man-made and engineered barriers.  Since boreholes are modular (i.e., capacity can be expanded as needed), they’ll create less programmatic risk and could be valuable to countries with smaller inventories.

Q. You worked at two advanced nuclear reactor companies before coming to Deep Isolation. Please tell us about these experiences and why you’ve chosen to focus on the back end of the fuel cycle.

I had the rare opportunity to work at both TerraPower and Oklo and attended MIT alongside the founders of Transatomic.  In this way, I’ve lived the dream that a young engineer might have after watching the movie, “A New Fire,” a compelling and inspiring documentary about these three advanced nuclear companies.

I was strongly drawn to TerraPower’s vision of bringing bright nuclear engineers together to design and deploy an advanced sodium-cooled nuclear reactor in the near term.  There I analyzed the safety of their reactors and focused on validating the accuracy of accident simulation codes.  The most rewarding part of my time there was traveling to the International Atomic Energy Agency (in the real, not “model” United Nations) to present the findings of the work I had started as an intern.  That led to an invitation to present our findings at a conference in Yekaterinburg, Russia, where I was the only American in attendance and toured their sodium-cooled fast reactors. 

The challenge of nuclear waste disposal is shared by many countries and should be solved soon if there is to be a significant (and much needed) expansion in nuclear power.  Advanced nuclear reactors will still produce significant amounts of waste, and the front-runner concepts are not positioned to rapidly deal with the existing and growing inventory of spent fuel.  Thus, although I had opportunities to continue in the advanced nuclear industry, I ultimately decided to refocus on disposal.  I believe I can benefit the industry the most (and thus help combat climate change) by designing, testing, and deploying a borehole repository.  I was also attracted by the rewarding sense of empowerment, mutual respect, and mission of the Deep Isolation team.

Q. Any Deep Isolation accomplishments you’d like to highlight so far? What would success look like to you moving forward?

I’ve been able to pick up where I left off with my MIT research and begin fulfilling my goal of bringing it to reality.  Over the past five years, Deep Isolation has made great advancements in borehole design and performance analysis. By applying systems engineering principles, I’ve structured these efforts within an overarching concept of operations.  Breaking the large complex problem into organized and manageable pieces enables us to prioritize them and build more a detailed and robust technology commercialization pathway.  I’m also leading our collaboration with external industry experts to improve the deep borehole community’s collective understanding of long-term safety analysis assumptions.

Moving forward, success requires continuing development of technical partnerships, customer relationships, and government funding sources across the globe. We’ve assembled excellent teams to lead each of these areas and our progress so far is encouraging.

In the near term, techno-economic models which reveal performance trade-offs and limits as a function of various host rocks, waste types, loadings, and other design assumptions will enable optimization of design configurations.  Using these methods, we can also generate site selection criteria specifying where and under what conditions deep borehole repositories can be safely built.  Combining this with customer-specific requirements, the design can be refined, and a complete set of technical requirements can be established.

In parallel, a well-planned and executed demonstration program would be a major success for the industry, building broader confidence, establishing trust, and signaling that the technology will be ready to commercialize and scale.

Q. Tell our readers something about yourself that they might not expect to know about a nuclear engineer.

Most people wouldn’t associate nuclear engineers with music or dancing, but I really enjoy playing guitar and dancing Argentine tango.  Musically, I’d say my style is blues-rock with an infusion of jazz.  I performed for many years as a student at MIT’s “Battle of the Bands,” have danced in tango festivals all over the U.S., and even taught a series of tango classes at a university.

Event, September 8-10, 2021

World Nuclear Association Symposium 2021

Deep Isolation will present at the WNA Symposium in London, this September. Top nuclear industry leaders, experts and executives will come together to share information and experience that will elevate nuclear energy as a key contributor in the transition to a clean and sustainable world.

Blog by Kari Hulac, June 8, 2021

Our Podcast Celebrates its First Year

When I was hired at Deep Isolation in early 2020, I was eager to apply my experience in news, social media and renewable energy marketing to a new-to-me topic: nuclear waste disposal.

However, of the skills listed on my resume, “podcast host” was not among them. So when two weeks into my job I found out that, “Oh yes, the company was very much in need of a host for a new series about nuclear waste,” I won’t lie: I gulped.

Nuclear Waste: The Whole Story logo
Deep Isolation’s podcast was established in the spring of 2020.

But when I discovered that it would be my role to represent people similar to myself — nuclear industry outsiders mostly unaware of this hidden-in-plain-sight worldwide problem — I knew it was something I was willing to try.

The goal was for Nuclear Waste: The Whole Story to embody one of the most important elements of a successful nuclear waste disposal program: the ability to listen, to recognize, and to understand different perspectives on nuclear waste and all of its dimensions; as a former reporter and editor, those objectives were in my comfort zone.

Afterall, what better way is there to collect as much wisdom as possible on a complicated topic? Now, a year later, we have released 12 episodes with plenty more to come. We’ve also incorporated additional hosts (Liz Muller and Sam Brinton) to provide valuable insights to these conversations.

I’m happy (and relieved!) to say the podcast has earned a five-star rating on Apple, with listeners saying they appreciate its “to the point and direct vibe” and the expertise of our interviewees, who include citizen activists, nuclear industry veterans, government leaders and scientists.

I’ve learned so much from each and every one of these guests and am grateful for their willingness to speak openly about the challenges they face in their respective efforts to tackle this controversial problem.

Don’t Miss Our New Podcast Highlights Reel

There are too many highlights to mention, but we’ve assembled some of them into a short montage that I hope you’ll take a few minutes to watch or listen to.

The highlights reel includes Kara Colton, who points out that nuclear waste — often incorrectly portrayed as “green goo” ala “The Simpsons” — can be an object as seemingly innocuous as a glove or a broom.

Or there’s the episode with Judy Treichel and Steve Frishman, two “ordinary” citizens who’ve spent 30 years informing the public about the U.S. government’s plan to build a mined waste repository in Nevada. They discuss how their effort eventually led to Yucca Mt. being put on hold because, as they said the states residents believe, “Nevada is not a wasteland.”

New episodes are added monthly. Watch or listen at or subscribe via Apple, Spotify, Amazon or Google. The series is also a playlist on our YouTube channel.

Please note: Although Deep Isolation is the producer, any opinions expressed by either the interviewers or their subjects do not represent our official company position.

And as always, we’d love to hear from you! Who should interview next? What questions about nuclear waste would you like answered? Just send an email to

Blog by Liz Muller, June 1, 2021

Deep Isolation Marks Five-Year Anniversary

When Richard Muller and I founded Deep Isolation five years ago, we were inspired by a strong desire to do big things to help fight global warming.

It was evident to us that nuclear energy would have to be part of the low-carbon energy mix but that it had to be done responsibly and that it wouldn’t succeed without a waste solution.

When we realized the answer was hiding in plain sight — using advances in oil and gas drilling technology to engineer deep boreholes to safely and permanently isolate the waste — the company was born.

At the time our close friends and advisors from the nuclear industry told us we’d be better off spending our time on something that had a future. Nuclear waste disposal, they explained, could never get done. This week, in recognition of our June 13, 2016 founding anniversary, I’m pausing to reflect on how much has changed. Even though we have not yet disposed of any waste, most people in the industry now believe that we will. I am so proud of our team and what we have achieved. We have broken through barriers that many thought were impossible to overcome by assembling a strong team around a common vision.

Here are some of our most notable achievements, as well as some of my thoughts about what I hope the nuclear industry will look like by our 10th anniversary.

Deep Isolation’s Progress So Far

After we filed our first patent in 2015, Deep Isolation was officially incorporated the following year. We quietly began reaching out to environmental groups and other stakeholders across the U.S. solely to listen and learn, and we recruited our first team member (who crashed at our Berkeley, Calif., home-based headquarters!).

We knew from the beginning that a successful nuclear waste disposal initiative would never succeed without community involvement, and it remains a core company value.

We knew we were being disruptive. We knew that the concept of a private company tackling a problem that has plagued the nuclear industry and governments for decades would be difficult for many to embrace. But we were galvanized by our early successes, most notably holding a public demonstration where we emplaced and retrieved a prototype nuclear waste canister from a borehole.

The 2019 demo established us as serious players in the nuclear industry, and soon after we forged partnerships and working relationships with international industry leaders including Bechtel, Schlumberger, and NAC International Inc. With these partners, plus the recently announced MOU with Dominion Engineering, Inc., we have all the elements of the fuel cycle disposal ecosystem in place.

In 2020 we announced a London-based team to serve our international market, and we landed and completed our first several paid contracts to study disposal options in specific rock formations.

Now, we are humbled to be part of the global conversation on nuclear waste. Borehole disposal, which had been studied extensively for years in the vertical formation, is seeing a resurgence in interest from governments and organizations all over the world.  Not only do I hope this continues, but that it also encourages the industry to support more innovation in disposal technologies.

And in public conversations about nuclear energy, there’s finally a more hopeful answer to the decades-old waste question. As one supporter said in an online forum recently: “As for disposal, check out Deep Isolation, a cool company thinking outside the pool on where spent fuel can go.”

Liz and Rich Founders
Liz and Rich – Founders of Deep Isolation

Five-Year Vision for Nuclear Waste Disposal

The future has never been more exciting for Deep Isolation. Our team is growing quickly, and no, no one is on our couch at the moment. We’re entering our next stage of fundraising and eyeing service contracts with multiple countries worldwide.

Here’s my vision for five things I hope Deep Isolation and the industry as a whole achieves in the coming five years.

1. All countries with waste are moving forward toward deploying a permanent nuclear waste disposal solution that is based on equitability and social responsibility and can be implemented in years not generations.

2. Countries that opt to deploy new reactors will select, site, and fund a disposal option before the reactor is built.    

3. Governments and industry will encourage new waste disposal options and allow (even encourage!) private innovation, including in approaches to stakeholder engagement and working with repository host communities.  

4. Investors and the public will understand that nuclear waste disposal technologies are pivotal in the fight against climate change.

5. Deep Isolation will have proven the cost, safety, equity and other benefits of its solution, and the company culture will continue to emphasize supporting one another, and always prioritizing what is truly important.

In this episode of My Nuclear Life, hosts Shelly Lesher and Lexie Weghorn sit down with Elizabeth Muller, co-founder and executive director of the environmental science non-profit, Berkeley Earth, and CEO of Deep Isolation, a first of its kind company offering innovative solutions to the challenges facing the nuclear waste storage and disposal industry. 

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For more information about our solution, please contact us. 415 915 6506

Deep Isolation, Inc.
2120 University Avenue, Ste. 623
Berkeley, CA 94704