Podcast Summary: "The State and Future of Nuclear Waste"

Catalyst with Shayle Kann | Released March 26, 2026
Guest: Dr. Jen Schaefer, Professor at the Colorado School of Mines
Host: Shayle Kann
Producer: Latitude Media

Episode Overview

This episode explores a crucial and complex piece of the nuclear energy puzzle: nuclear waste. While optimism grows around a new wave of nuclear power development in the U.S., the reality of long-lived, radioactive waste lingers as a deeply misunderstood challenge. Shayle Kann sits down with Dr. Jen Schaefer to demystify the composition, management, and future strategies for handling nuclear waste—including technological, regulatory, and social hurdles that stand between today’s stockpiles and a sustainable nuclear future.

Key Discussion Points & Insights

1. What Is Nuclear Waste?

[03:20 – 04:39]

• Composition: Most U.S. commercial nuclear waste is uranium dioxide (“ceramic, like your coffee mug”), which is solid, not a “liquid goo” like pop culture suggests. [03:27]
  • 95% of spent fuel remains unreacted uranium.
  • The remaining 5% consists of fission and transmutation products: plutonium, neptunium, americium, and various other isotopes.
• Notable Quote:
  • “It stays in the fuel. It's a solid. Some people are surprised... It's not a liquid goo. I've just been watching Teenage Mutant Ninja Turtles with the kids recently. So that's not what it is.”
    – Dr. Jen Schaefer [04:22]
  • “Also The Simpsons. Also The Simpsons green radioactive goo. Yep.”
    – Shayle Kann [04:35]

2. Why Is Nuclear Waste Challenging to Manage?

[05:11 – 06:27]

• Radioactivity Timeline:
  • Actinides (e.g., plutonium) drive the long-term hazard, with half-lives (and thus, risk) spanning tens of thousands to millions of years.
  • Some fission products, like technetium-99 or certain iodine isotopes, also have long-lasting radioactivity.
• Legal and Social Constructs:
  • Regulatory obligations (e.g., Yucca Mountain’s “10,000-year management obligation”) are societal decisions about how long we expect to manage the waste.
  • Even though most waste becomes manageable in hundreds of years, a tiny fraction (actinides, specific fission products) persists for millennia.
  • “Really it boils down to the social construct ... we are going to manage it for the long haul.”
    – Dr. Jen Schaefer [07:21]

3. Nuclear Fuel Recycling & Waste Minimization

[09:42 – 13:15]

• Current U.S. Practice: Open fuel cycle—fuel is used once and then stored, generating more waste.
• Recycling Possibilities:
  • Recycling can minimize the volume of long-term waste, especially if coupled with fast reactor technologies for repeated irradiation cycles.
  • Current U.S. reactors (light water) aren’t suited for near-infinite recycling; advanced fast reactors could better enable this.
  • Advanced particle accelerators may allow for active waste transmutation in the future.
• Shift in Waste Profile:
  • Effective recycling could allow future waste to be far less hazardous in the long term—comparable to the waste profile from fusion (mainly hundreds, not thousands, of years to manage).

4. The U.S. Nuclear Waste Inventory and Policy Stalemate

[13:15 – 19:34]

• Current Stockpile: ~90,000 metric tons of used nuclear fuel in the U.S.; growing by about 2,000 metric tons per year.
• Historic Plan: Deep geological storage at Yucca Mountain was legally adopted but never implemented (project defunded in 2009 after local/state opposition).
  • Waste is now stored at reactor sites or centralized storage facilities.
  • Utilities (and their customers) have paid into a federal nuclear waste fund (~$50B), but since the government hasn’t accepted the waste, utilities are reimbursed for ongoing storage costs.
• Notable Quote:
  • “We basically have the stasis where we haven't necessarily taken action with respect to what to do with our nuclear waste next, but this is still basically what's our holding pattern.”
    – Dr. Jen Schaefer [15:33]

5. What Does Waste Storage Look Like Practically?

[19:34 – 23:11]

• Spent Fuel Pools: Used for initial cooling (about a decade) after removal from reactors; provide radiation shielding and thermal management.
• Dry Storage Casks: After cooling, waste is moved to large, passive concrete casks—“pretty unremarkable”—requiring minimal oversight beyond security.
• Safety:
  • Once in dry casks, waste is largely passive. Early-phase (pool) cooling requires active management—a lesson from Fukushima.
  • Notable quote: "It’s really pretty unremarkable in its way. You can imagine it sitting in a parking lot with the appropriate security..."
    – Dr. Jen Schaefer [20:53–21:16]

6. Impact of New Reactor and Fuel Types

[23:11 – 26:28]

• Fuel Forms Matter:
  • Ceramic fuel (e.g., uranium dioxide, TRISO) is durable and safer for long-term disposal.
  • Molten salt or metallic fuels may require additional conditioning before disposal.
  • Sodium-bonded fuels pose extra regulatory challenges due to chemical reactivity.
• Reactor Trends:
  • High-temperature gas reactors using TRISO: easy waste management.
  • Molten salt reactors using dissolved fuels: need significant pre-disposal treatment.
  • Fast reactors (like TerraPower, Oklo): have pathways for recycling and waste processing built in.

7. Microreactors and Waste Management

[26:28 – 27:53]

• Microreactor companies typically propose “take-back” models: entire reactor modules (with spent fuel) are shipped off-site for professional management.
• Transporting nuclear material is possible under current regulations, but state-level opposition remains a potential barrier.
  • “If a state does not want you to move nuclear material through the state, it will find a way for you to not move nuclear material through the state.”
    – Dr. Jen Schaefer [27:53]

8. The Future: Will the U.S. Ever Have a Centralized Repository?

[29:01 – 34:28]

• Social acceptance for a single-state national repository is low unless paired with local benefits like recycling facilities and research labs.
  • Studies show communities more open with greater incentives (jobs, labs, recycling).
  • International models (e.g., Finland) achieve community buy-in for national waste solutions.
• Even if Yucca Mountain opened, its legal limit is 70,000 metric tons; we’ve already exceeded that.
  • Scaling up nuclear energy (“tripling or quadrupling”) would require many more (or much larger) repositories, intensifying the political & social challenge.
  • New borehole disposal technologies may enable decentralized, state-level solutions.
  • “I almost feel like this could even be a more socially acceptable situation for a state to just manage its own material.”
    – Dr. Jen Schaefer [32:50]
  • Engaging state-level stakeholders early is crucial to any viable solution.

Memorable Quotes & Moments

• "It stays in the fuel. It's a solid. Some people are surprised… It's not a liquid goo."
  – Dr. Jen Schaefer [04:22]
• "Really it boils down to the social construct… we are going to manage it for the long haul."
  – Dr. Jen Schaefer [07:21]
• “We basically have the stasis where we haven't necessarily taken action ... We haven't actually taken action with respect to what to do with our nuclear waste next, but this is still basically what's our holding pattern.”
  – Dr. Jen Schaefer [15:33]
• “If a state does not want you to move nuclear material through the state, it will find a way for you to not move nuclear material through the state.”
  – Dr. Jen Schaefer [27:53]
• "I do think that there is a component of engagement with respect to what are the things that will really encourage people to come to the table with respect to management of this."
  – Dr. Jen Schaefer [30:29]

Timestamps for Key Segments

• 03:18 – 06:27: What nuclear waste is, chemically and physically.
• 06:27 – 09:42: Timeline of waste toxicity and the regulatory/social approach.
• 09:42 – 13:15: Open vs. closed fuel cycle; recycling and its impact.
• 13:15 – 19:34: U.S. waste inventory, Yucca Mountain, and current policy impasse.
• 19:34 – 23:11: Physical storage practices: pools, casks, and facility management.
• 23:11 – 26:28: Influence of new reactor and fuel types on waste management challenges.
• 26:28 – 29:01: Microreactors and waste take-back, transport issues.
• 29:01 – 34:28: Will the U.S. ever have a central repository? Social, political, and technological possibilities.

Conclusion

This episode unpacks the complicated legacy and ongoing debates around nuclear waste in the U.S. Despite engineering advances and options for minimizing or recycling waste, progress is stymied by social and political gridlock, especially at the state level. As the U.S. eyes a nuclear revival, sustainable—and socially acceptable—solutions for nuclear waste remain both a technical challenge and a litmus test for the energy transition’s success.

For further reading and resources, visit latitudemedia.com.

End of summary.