Madi Hilly Profile picture
Jul 28, 2022 27 tweets 7 min read Read on X
My thread on nuclear waste seems to have touched a nerve!

Interestingly, most pushback has come from INSIDE the nuclear industry, not outside.

A follow-up on the physics & culture of nuclear waste, & why the industry has gotten it wrong for so long:
When people want to talk about the waste, they want answers to two questions:

1. Is the waste safe today?
2. Is the waste safe after the apocalypse?

Let’s start with the first.
The rule of thumb for radiation is as follows:

Short half-life means higher radioactivity (think spicier) but for a shorter time.

Long half-life means lower radioactivity (less spicy) but for a longer time. Graph illustrating the amount of time it takes for substance
Very short half-life products are of little concern here because, by definition, they've lost most of their radioactivity by the time the fuel rods have been sitting in water for several years.

Therefore much of waste management is dealing with longer-lasting fission products.
There are two categories of “waste” to deal with:

1. Fission products (atomic “fragments” lighter than uranium)
2. Transuranics (​​radioactive elements heavier than uranium)

Both types are contained within ceramic pellets that make up the fuel pellets inside of the fuel rods.
Fission products like Cs-137 and Sr-90 come from the splitting of uranium.

Fission products typically have shorter half-lives compared to transuranics. As such, they are responsible for most of the heat and penetrating radiation of the waste. A graph showing the radioactivity of typical spent nuclear f
Transuranics like Am-241 & Pu-240 are the result of uranium absorbing neutrons but not fissioning.

They usually have a long decay chain which gives them a long effective half-life. They don’t produce nearly the heat of fission products, but their radiation sticks around longer. A graph showing the radioactivity of typical spent nuclear f
Transuranics can be "eaten up" in breeder reactors, meaning they can become fuel and then fission products.

This would make the remaining waste short-lived compared to traditional spent fuel.
I asked radiation expert @ThatRadGuy5 about a worst case scenario: what if a cask got cracked open?

“If the cask were damaged, it would not be catastrophic. If anything, it would just lose its seal and lose inert helium gas. Essentially all material would stay contained.”
I urged him to use his imagination.

“It would not be a good day (an accident that was severe enough to damage a cask would need to be unprecedented), but there would likely not be harm caused by radiation, and the land would not really be affected.”
That gets to the heart of my 1st thread: there are many other materials that are more hazardous and that we store in less secure ways.

Anhydrous ammonia (used for fertilizer) is far more dangerous, but we make & transport millions of metric tons per year because it feeds us.
So we know the waste is safe today. When it's in casks, you can lie on it, stand on it, hug it, whatever.

Time to get to the doomsday question: what happens to the waste after the apocalypse?

Over the past 5 years, I’ve been asked about the following scenario MANY times:
"What if, thousands of years from now, someone comes across casks containing nuclear waste? Encountering them for whatever reason, from bad luck to curiosity. And what if they don’t read English but possess the brute power to cut through thick reinforced concrete and steel?"
You can’t understand this question if you take it at face value.

We already know that nuclear waste isn’t uniquely dangerous.

We've had written material passed along & understood for 4500 years, give or take.

Radiation detection devices are cheap and widely available.
But this post-apocalyptic scenario provides insight into how people think about nuclear power.

Folks asking this question are imagining there will be a “clean slate” apocalypse, which is almost always represented as a nuclear apocalypse.
*When people are asking this question, they are expressing their nuclear fears in the present by projecting them onto the future and onto the waste*
In many minds, there is no difference between nuclear power plants and nuclear bombs.

Cask of nuclear waste = small nuclear bomb
Nuclear plant = big nuclear bomb
Part of this can definitely be chalked up to the anti-nuclear movement (i.e. China Syndrome). Activists intentionally tried to falsely blur the line between the meltdown of a commercial nuclear power plant and the detonation of a nuclear bomb. Movie poster for the "No Nukes" documentary and co
But rather than pushback against the idea that nuclear power & its waste are uniquely dangerous, the industry internalized it!

Industry professionals will tell you the waste is safe. They will also tell you that we have to bury it deep underground or shoot it into the sun.
This is just another example of the nuclear industry trying to respond to social concerns with costly technological “solutions”.

But ironically because of the sheer cost and effort involved, those fears are *confirmed*, not diffused.
To be clear, this thread is NOT an argument to be less intentional about our plan for proper waste management!

It’s meant to demonstrate the problems that arise when you fail to differentiate between a communication problem and a science problem.
So what should we do with the waste, exactly? People in the industry complained there was no specific plan laid out.

I talked to nuclear energy expert @energybants to outline what the start of a good waste management program should look like.
First, continue the current system of assuring physical safety with dry-casks and monitoring. @energybants spending some quality time with spent nuclear f
Second, build public trust through facilities that manage either reprocessed waste or unprocessed waste in a visually compelling, accessible, and informative way.

@ThatRadGuy5, @energybants and I are all big fans of how the Dutch have pulled this off.
Next, put in place a deliberation plan. The Dutch have this too.

They plan to have a geological repository by 2100. Every 10-20 years they touch base on the issue. The result has been “we’re still doing research & watching the rest of the world, talk again in another 10-20.”
In this case, it’s responsible to wait! Everything about nuclear waste gets cheaper the longer you wait, making it the exact opposite of every other infrastructure project we work on.

And we know it’s safe today, so what’s the rush?
Lastly, we need to leave a fleet of working reactors for future generations. Maintaining systems and protocols makes things easier for everyone involved. And there’s the added benefit of abundant, reliable, carbon-free power.

Win-win! Double rainbow over the Byron Nuclear Power Plant in Illinoi

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More from @MadiHilly

Aug 4, 2023

Oppenheimer is a profound exploration of nuclear fear, offering clarifying insights into the nature of our anxieties and revealing why this fear seems to be unique to nuclear

Some highlights from my latest:


The movie implies the existence of a very small chance that the world might've ended as a result of the Trinity Test.

In actuality “near zero” simply means non-disprovable – the inability to say something cannot happen through theory or observed evidence. Photo: Universal Pictures

Our deepest fears of nuclear exist in the realm of “near zero”. They manifest in fantastical scenarios with probabilities infinitesimally small and no definite way to disprove their existence.
Read 29 tweets
Jun 22, 2023
Yesterday, the same lawmakers in New York who frequently demand we Believe the Science instead went with Feels Over Reals, passing a bill to ban the release of wastewater from the shuttered Indian Point nuclear plant into the Hudson.

Here's what you need to know:
The wastewater in question is tritiated water — water containing trace amounts of a radioactive isotope of hydrogen called tritium.

Tritiated water is regularly released by nuclear plants as part of normal operations because the concentration of tritium is so incredibly low.
How low?

The EPA sets an annual dose limit from liquid releases at 25 millirem, & the Indian Point site has a more conservative limit of 3 millirem.

In 2021, the total possible dose to the public from Indian Point liquid releases was 0.011 millirem, 0.3% of the allowable dose.
Read 9 tweets
May 17, 2023
@RobertKennedyJr ran through the anti-nuclear playbook during his interview on Breaking Points.

While there were too many errors and confusions to cover in one thread, I’ll touch on the main points I took issue with. Let’s clear the record:

@RobertKennedyJr asserts that energy policy is written “to benefit the dirtiest, filthiest, most poisonous, most toxic, most war-mongering fuels from hell”

“[Polluters] raise standards of living for themselves by lowering quality of life for the rest of us”
Cringe aside, it's dishonest to look at pollution from energy in a vacuum.

Increasing energy consumption over time has coincided with greater levels of healthcare, education, democracy, security, & economic freedom.

Historically, these advances have been powered by fossil fuels
Read 20 tweets
Mar 20, 2023
@jackdarin – director of @SierraClubIL – claimed that the Sierra Club doesn’t support lifting the state’s ban on new carbon-free nuclear because “we believe that nuclear is not clean energy”

Frustrating to have to debunk this anti-nuclear talking point in 2023, but let’s do it: From "Future of nuclea...
@jackdarin says nuclear’s “full life cycle has very serious impacts”

@OurWorldInData studied the lifecycle emissions of our energy sources, including from mining, transportation & maintenance over a power plant’s life.

The data shows nuclear has the LOWEST lifecycle emissions. Source: https://ourworldind...
@OurWorldInData also studied lifecycle land use – not just the land for the power plant, but also to mine the materials for its construction and fuel, to connect to the electricity grid, and to manage any waste that is produced.

Nuclear comes in at #1, requiring the least land. Source: https://ourworldind...
Read 12 tweets
Mar 10, 2023
Illinois is *SO CLOSE* to lifting its ban on new nuclear

To get these bills over the finish line, representatives and senators need to hear from all Illinoisans that this is the right thing to do for our state

Alan explains exactly how to make your voice heard👇
RECAP: Illinois’s nuclear moratorium was passed in 1987 back when carbon was irrelevant to environmentalists.

Nearly 40 years later, we understand the need for reliable, carbon-free nuclear powering our state regardless of time of day or season.
The moratorium was passed under the premise that we had no solution to nuclear waste. But that's not true!

U.S. management of spent nuclear fuel has a perfect record on safety and environmental protection.

You can read more here:
Read 5 tweets
Mar 9, 2023
I've been disappointed in content coming from @sciam for a while now, so I guess I'm not surprised to see this.

Let’s examine these claims:

1. Is nuclear waste “piling up”
2. Is nuclear waste becoming unsafe?
3. Do we need a repository now? Image
The title of the article claims that “Nuclear Waste Is Piling Up”

It goes on to say that “Before we face that onrush” of waste coming from new reactors that may get built, “we first need to deal with the large volume of waste we’ve already produced”
The figures to support these claims are as follows:

“88,000 metric tons of spent nuclear fuel from commercial reactors…and this number is increasing by some 2,000 metric tons each year”

Without any additional context, that sounds like a lot of waste! But how much waste is it?
Read 26 tweets

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