When you pass a nuclear power plant in the
distance as you drive down the road, it’s impossible not to think about the power these
towering buildings hold. Scientist Enrico Fermi supervised the opening
of the first nuclear power plant in 1942, and now our landscapes are dotted by mighty
nuclear reactors. These powerful energy plants provide over
a fifth of the United States’ electricity, and don’t have the carbon footprint of other
energy sources like coal and fossil fuels. So why not build more? One reason - nuclear waste and radioactivity. When managed correctly, nuclear plants are
processing powerful radioactive energy that needs to be disposed of correctly to keep
the environment and the people handling it safe. And if someone wasn’t handling the plant’s
safety correctly, like a certain bald bumbler from Springfield, things could go very badly. D’oh. The risks of nuclear energy became crystal
clear in 1979 in Londonderry Township, Pennsylvania at the Three Mile Island nuclear plant. While the reactors were stable, a failure
in the mechanical systems regulating the safe venting of gases broke down, and allowed a
large amount of nuclear reactor coolant to escape. That led to a partial meltdown of Reactor
2, creating a major radiation leak near the city of Harrisburg. A voluntary evacuation of a twenty-mile radius
around the plant followed. Thankfully, no one in the plant was injured
and later tests showed no increased risk of cancer, but it took fifteen years to clean
up the surrounding area. It remains the worst nuclear accident in United
States history - but is dwarfed by the massive nuclear meltdown in Chernobyl, which caused
major casualties and rendered areas surrounding the Ukrainian plant uninhabitable to this
day. Given the risks, it’s no surprise that nuclear
waste and by-products are strictly regulated by the government. Modern nuclear plants keep waste to a minimum
by recycling used fuel back into uranium-based and mixed-oxide fuel, but four percent of
nuclear waste can’t be processed and remains highly radioactive. Radioactivity is a waiting game, as the toxic
quality of the waste decreases over time. Measured in half-life, or the time it takes
for a radioactive substance to reduce to half of its nuclear value, the time it takes for
nuclear waste to neutralize varies wildly. Some common isotopes like Strontium-90 have
a half-life of around thirty years, but other powerful artificial nuclear isotopes like
Plutonium-239 have a half-life of over twenty thousand years. Not only is it radioactive enough to kill
anyone exposed to it, but it could be an unpleasant surprise for whoever digs it up in the far
future. Nuclear power plants operate in thirty-one
countries, including all of the world’s largest economies, and much of Asia and Africa
are planning new builds. The regulation of nuclear waste is overseen
by the International Atomic Energy Agency’s joint convention on spent fuel management,
and they work to keep the world safe. The risks of exposure to nuclear waste include
higher risk of cancer, higher risk of birth defects in pregnant women, and in high concentrations
organ failure and death. Most nuclear waste comes from nuclear power
plants and nuclear arms, but medical and industrial waste and natural radioactive materials also
pose a risk. Nuclear waste comes from two main sources
- front-end and back-end. Front-end nuclear waste comes from the extraction
of uranium, and contains radium. The depleted uranium that comes from it is
extremely dense and is often recycled into anti-tank shells and other metals where extreme
durability is needed. Back-end nuclear waste comes from spent fuel
rods and is packed with beta and gamma radiation. These powerful energies come with extremely
long half-lives and are formed in nuclear reactors. Some of the most challenging waste to dispose
of comes from nuclear weapons materials, and the plutonium used to create these powerful
bombs is extremely difficult to separate and isolate. That makes nuclear weapon disposal a growing
concern, especially in the aftermath of the cold war when the US and Russia drastically
slashed their nuclear arsenals. The world is less likely to end now, but what
are we going to do with all those things that can end the world? The classification of nuclear waste determines
the priority level of the processing and disposal. The lowest-priority nuclear waste is uranium
mill tailings, which are created by the rough processing of uranium ore. While they don’t contain a high level of
radioactivity, they have long half-lives and are full of metals with other health risks
like arsenic and lead. Low-level waste is the most common waste type,
because it’s anything that came into contact with radioactivity. Common in hospitals and processing plants,
it can include paper, clothing, tools, and filters that are used by people working with
nuclear energy. These objects pick up trace levels of radioactivity
and should be disposed of safely instead of being processed with standard trash. Intermediate waste is usually the by-product
of nuclear processing, and is harder to dispose of than low-level waste. Resins, chemical sludge, and metal coverings
that have been exposed to nuclear energy long-term pick up the harmful radioactivity and the
hazardous nature builds over time. When breaking down a nuclear reactor for decommissioning,
even the building materials surrounding the core can build up radioactivity. Before disposing of this waste, it should
be safely shielded to prevent exposure. Then there’s high-level waste, and this
is what everyone thinks about when they hear about nuclear power plants. The alarms start blaring. The hazmat suits go on. High-level nuclear waste is as radioactive
as you think, but the good news is there are effective waste to contain it. When a nuclear fuel rod serves its purpose
and is taken out of the core, it becomes high-level waste. While the number of high-level waste objects
is small compared to the other classes, the level of radioactivity is so high that it
accounts for over ninety-five percent of total radioactivity caused by nuclear energy. While most radioactive isotopes produced by
high-level waste are high-powered but have a short half-life, the presence of isotopes
like plutonium makes it critical to ensure it’s contained safely. So what’s the best way to dispose of nuclear
waste? That’s what nuclear-energy using countries
have been arguing over for decades. Most experts say the best solution for long-term
disposal is by constructing a deep underground facility, similar to a mine, that can contain
large amounts of high-level waste away from humans and be sealed up in between disposals. But that’s easier said than done, and no
country has finished one - although Finland is close to completing their Onkalo spent
nuclear fuel repository on their west coast. Currently, countries use a number of alternative
systems that are considered safe, but imperfect. The first step to minimize the impact of nuclear
waste on the environment is to neutralize it as much as possible. This is done by processing it and stabilizing
it into a form that loses its explosive properties. Some countries mix the waste with sugar and
then calcinate it into a solid object by processing it through a rotating tube. Turned into glass, the waste products are
bonded to the other molecules and then poured into stainless steel and sealed. They’re then stories underground, where
the waste products are trapped for thousands of years without leaking radioactivity into
the environment. Other technologies include ion exchange, where
medium-level wastes are neutralized by concentrating the radioactivity into a much smaller volume. This makes them easier to contain, but isn’t
recommended with the volatile high-level wastes. But when the time range for nuclear waste
to become deactivated can reach into the millennia or longer - with some rare isotopes having
a half-life of over a million years - scientists are concerned that these storage methods could
come back to haunt us. That’s why we’ve eliminated many of the
more short-sighted methods of nuclear waste disposal, like ocean disposal. Up until the 1990s, many countries including
the United States and the Soviet Union would dump drums of contained nuclear waste into
the ocean, especially in the coastal regions of Somalia. Somalia hasn’t had a functioning government
since the 1990s, and the pirates weren’t going to mess with a large ship bearing a
country’s flag when they could go after smaller merchant ship, so countries thought
anything goes out there. The Arctic ocean was also a popular choice
for the Soviets, as they controlled a huge coast in the north. Overall, 137,000 tons were dumped in the water
by European countries in thirty-four years, and it took its toll on the oceans. Tests of areas where dumping was common found
elevated levels of radioactivity, and in 1993 a treaty was passed banning ocean disposal
of nuclear waste. The most common current method for nuclear
waste disposal is above-ground disposal, where waste is sealed up in a steel cylinder with
an inert gas that won’t react with it, and then sealed in radiation-shielding concrete. The radiation-proof drums are then sealed
in a storage facility near the nuclear power plant. This is how big plants handle their waste
in-house, and it’s popular for a few reasons. First, it’s handled internally and the plant
doesn’t have to get approval and fight their way through government red tape to find a
dumping facility. Second, it’s inexpensive and doesn’t require
construction or expensive materials. Finally, the waste remains on site for reprocessing
- which remains the best solution for solving the nuclear waste question. The secret weapon for eliminating nuclear
weapons is chemists and physicists, as these scientists have developed ways to chemically
separate fission products and unused uranium from used nuclear fuel. This started by extracting Plutonium, with
its long half-life, from nuclear fuel to be used in the construction of nuclear weapons. But as the focus shifted from bombs to energy
plants, scientists developed ways to create a new type of nuclear fuel from the remnants
of the old. MOX nuclear fuel, or mixed oxide fuel, is
created in high-level facilities from nuclear waste coming from plants around the country,
and has become a top way of disposing of nuclear waste in Europe. In America, the government is focusing on
research and commercial nuclear fuel reprocessing isn’t widespread yet. So what will nuclear waste disposal look like
in the future? One of the biggest possibilities is space
disposal, as this will get the radioactivity as far away from people as possible. The problem (besides the possibility of poisoning
some aliens that will come looking for revenge) is that technology isn’t there yet. While technology like mass drivers and space
elevators is in development, the carrying capacity of our current space shuttles is
limited and would only be able to carry a small amount of nuclear waste. The money that goes into every space shuttle
launch is high, and the program is far from fool-proof. The loss of the Challenger and the Columbia
shuttles proves that a catastrophic accident is possible - and a space shuttle disaster
carrying a nuclear payload could contaminate a large area. Could we transform nuclear waste into less-harmful
waste with a shorter half-life? That was the dream of the scientists behind
the Integral Fast Reactor, an experimental reactor that would use a nuclear fuel cycle
that reprocessed fuel through electrorefining. It would extract almost all the energy contained
in uranium, cutting fuel requirements by two orders of magnitude. Unfortunately, the design had problems with
leaking cooling fluid and the project was cancelled by the US Government in 1986, but
research is ongoing and new fission reactors that have much more processing power than
the traditional light water reactors are under development now. The earth itself might be our best ally for
disposing of nuclear waste, as man-made structures underground are the top proposal for future
storage facilities. By digging out large, stable bunkers in sparsely
populated areas of a country, nations could keep their nuclear waste in a centralized
location and reduce the risk of leaks happening in multiple locations. Deep borehole disposal is an alternative that
creates narrower but much deeper holes capable of storing the waste up to three miles under
the Earth, where any leaks would be far away from humans. The big holdup? Besides developing the technology for safe
deep-earth drilling, getting approval from governments is a holdup. Many countries have rejected proposals out
of fears that the disposal won’t be safe or that it could destabilize the ground. The consequences of a nuclear accident are
massive and long-term, as the residents of Pripyat, Ukraine know all too well. In the heart of the Chernobyl nuclear plant
is the Elephant’s Foot, a mass of solid nuclear waste caused by the 1986 meltdown. Dense and hard to damage, it was so radioactive
when released that it would kill anyone who was in the same room as it. Today, over thirty years later, it’s still
highly radioactive and poses major health risks to anyone who is exposed. So however we neutralize our nuclear waste,
let’s make sure it stays there. Want to learn more about the worst nuclear
disaster in history? Watch “How I Survived Chernobyl” or check
out this video instead. Thanks for watching, and as always, don’t
forget to like, share, and subscribe. See you next time!
