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Lying on the remote northwest coast of England | 0:00:08 | 0:00:12 | |
is one of the most secret places in the country. | 0:00:12 | 0:00:15 | |
65 years ago, it helped make Britain a world superpower. | 0:00:19 | 0:00:23 | |
And within its walls is material that could devastate life on | 0:00:27 | 0:00:31 | |
this island and beyond. | 0:00:31 | 0:00:33 | |
This is Sellafield. | 0:00:35 | 0:00:36 | |
Costing around £2 billion a year, it's the most controversial | 0:00:38 | 0:00:42 | |
nuclear facility in Britain. | 0:00:42 | 0:00:44 | |
I'm a nuclear physicist | 0:00:45 | 0:00:47 | |
and I've been fascinated by this place for much of my career. | 0:00:47 | 0:00:50 | |
I've heard the stories about the extraordinary experiments, | 0:00:50 | 0:00:53 | |
the jaw-dropping machinery and the incredibly costly science. | 0:00:53 | 0:00:58 | |
And I've also heard about the problems, | 0:00:58 | 0:01:00 | |
the risks and controversies, the terrifying accidents. | 0:01:00 | 0:01:04 | |
I got a phone call, "Pile one's on fire." | 0:01:04 | 0:01:08 | |
I said, "Good God, you don't mean the core?" | 0:01:08 | 0:01:10 | |
He said, "Yes." | 0:01:10 | 0:01:11 | |
Now, they're giving me and the television cameras | 0:01:12 | 0:01:15 | |
access to discover the real story. | 0:01:15 | 0:01:17 | |
We're going inside Sellafield. | 0:01:17 | 0:01:20 | |
We've been given access | 0:01:26 | 0:01:28 | |
to some of Britain's most secret buildings. | 0:01:28 | 0:01:30 | |
It's eerie being so close to something so deadly. | 0:01:32 | 0:01:35 | |
That's the first time it's been touched in, probably, 51 years. | 0:01:38 | 0:01:41 | |
I'll be encountering some of the most dangerous substances on Earth. | 0:01:41 | 0:01:45 | |
It's your dose for the year. | 0:01:47 | 0:01:48 | |
-That's your dose for the year in one... -Yeah. | 0:01:48 | 0:01:50 | |
OK, so we should go out of the way now. | 0:01:50 | 0:01:52 | |
I'll reveal the nature of radioactivity. | 0:01:52 | 0:01:55 | |
And I'll even attempt to split the atom. | 0:01:56 | 0:01:59 | |
I believe that Sellafield tells a unique and important story... | 0:02:01 | 0:02:06 | |
..because it reveals Britain's attempts past, present | 0:02:09 | 0:02:12 | |
and future, to harness the almost limitless power of the atom. | 0:02:12 | 0:02:15 | |
It's why I think the tale of this place is one of the most | 0:02:15 | 0:02:19 | |
important scientific stories of our age. | 0:02:19 | 0:02:22 | |
I'm just about to go through the main gate and into Sellafield. | 0:02:38 | 0:02:41 | |
I have to say, I'm pretty excited, but also a bit nervous, because | 0:02:41 | 0:02:46 | |
I've had to go through some very tight security procedures to get in. | 0:02:46 | 0:02:50 | |
Over the last few months, all my personal details have been | 0:02:51 | 0:02:55 | |
heavily vetted by the security services. | 0:02:55 | 0:02:57 | |
And, of course, every piece of filming equipment has had to be | 0:02:59 | 0:03:02 | |
very, very carefully checked and re-checked. | 0:03:02 | 0:03:05 | |
Now, finally, we're ready to be let in. | 0:03:05 | 0:03:07 | |
This intense security is a reminder of how potentially dangerous | 0:03:13 | 0:03:18 | |
what's stored here actually is. | 0:03:18 | 0:03:20 | |
In the wrong hands, much of this material would be deadly. | 0:03:20 | 0:03:24 | |
From hereon in, we're operating under strict national | 0:03:26 | 0:03:29 | |
security procedures, and some of the images on this film | 0:03:29 | 0:03:33 | |
are going to have to be blurred out. | 0:03:33 | 0:03:35 | |
We can't show building numbers or routes or security cameras. | 0:03:35 | 0:03:39 | |
I can already see experimental nuclear reactors, power stations | 0:03:45 | 0:03:50 | |
and nuclear storage facilities. | 0:03:50 | 0:03:53 | |
There are over 1,000 separate buildings. | 0:03:54 | 0:03:57 | |
In fact, this site covers over six square kilometres. | 0:03:58 | 0:04:02 | |
It's the most complex nuclear facility in Europe. | 0:04:03 | 0:04:06 | |
One of the first impressions I get is that this place is buzzing | 0:04:15 | 0:04:19 | |
with activity. | 0:04:19 | 0:04:21 | |
Radioactive waste and spent nuclear fuel arrives here nearly every day. | 0:04:21 | 0:04:26 | |
In case of an incident, there are regular drills by the security | 0:04:28 | 0:04:32 | |
and emergency services. | 0:04:32 | 0:04:34 | |
And all with good reason, because some of the most dangerous | 0:04:36 | 0:04:39 | |
buildings in the world are here at Sellafield. | 0:04:39 | 0:04:42 | |
I'm going to start by visiting one, because in here are clues | 0:04:46 | 0:04:51 | |
that reveal the story of Britain's entry into the nuclear age. | 0:04:51 | 0:04:55 | |
This is one of the infamous Sellafield storage ponds. | 0:04:58 | 0:05:01 | |
The size of eight Olympic swimming pools, it's the largest open | 0:05:01 | 0:05:05 | |
nuclear pond in the world. | 0:05:05 | 0:05:07 | |
For about a decade, between the mid 1950s and 1960s, this five metre | 0:05:07 | 0:05:13 | |
deep water was used to store a huge range of nuclear waste, | 0:05:13 | 0:05:17 | |
all sorts of experimental nuclear fuels, highly radioactive | 0:05:17 | 0:05:21 | |
isotopes, hazardous irradiated debris and contaminated leftovers. | 0:05:21 | 0:05:26 | |
And, now, Sellafield is starting to clear these so-called legacy ponds. | 0:05:31 | 0:05:37 | |
I think go for this one. | 0:05:37 | 0:05:38 | |
The hundreds of tonnes of waste down here are a physical record of | 0:05:42 | 0:05:46 | |
the history of Sellafield. | 0:05:46 | 0:05:48 | |
And hidden deep within this debris is evidence of the top secret | 0:05:54 | 0:05:59 | |
project that started it all. | 0:05:59 | 0:06:01 | |
Britain's race to build an atom bomb. | 0:06:08 | 0:06:10 | |
In 1945, the world looked on in awe as these terrifying new | 0:06:12 | 0:06:17 | |
nuclear weapons were unleashed on Japan. | 0:06:17 | 0:06:20 | |
Their extraordinary power came from inside the atom. | 0:06:22 | 0:06:26 | |
And it was a German chemist, called Otto Hahn, who first stumbled | 0:06:27 | 0:06:32 | |
across the power inside an atom almost by accident. | 0:06:32 | 0:06:36 | |
In 1938, in his Berlin laboratory, Hahn was investigating | 0:06:37 | 0:06:42 | |
a metal called uranium. | 0:06:42 | 0:06:44 | |
This tiny disc is a sliver of uranium. | 0:06:48 | 0:06:52 | |
This is what the fuss is all about. | 0:06:52 | 0:06:54 | |
Now, uranium is the heaviest naturally occurring element. | 0:06:54 | 0:06:59 | |
Its nucleus is made up of over 200 particles, protons and neutrons. | 0:06:59 | 0:07:05 | |
Otto Hahn was fascinated by uranium and wondered what happens | 0:07:05 | 0:07:08 | |
when a single neutron hits the nucleus. | 0:07:08 | 0:07:13 | |
But what he found when he did his experiments... | 0:07:13 | 0:07:16 | |
made no sense at all. | 0:07:16 | 0:07:17 | |
Now, I know this is a cliche and I've said it many times before, | 0:07:22 | 0:07:25 | |
but this single experiment really did change the world for ever. | 0:07:25 | 0:07:29 | |
Without realising it, Otto Hahn had taken the first step | 0:07:31 | 0:07:35 | |
into the nuclear age. | 0:07:35 | 0:07:37 | |
For what we think is the very first time on television, | 0:07:39 | 0:07:42 | |
we're going to re-create a version of the actual experiment carried | 0:07:42 | 0:07:46 | |
out by Otto Hahn three-quarters of a century ago. | 0:07:46 | 0:07:49 | |
This accelerator will produce a beam of particles containing neutrons. | 0:07:50 | 0:07:55 | |
And I can drop this piece of uranium right in its path, just down here. | 0:07:57 | 0:08:02 | |
Now, turn on the beam. | 0:08:03 | 0:08:05 | |
Just like in Hahn's experiment, my uranium is being bombarded | 0:08:06 | 0:08:10 | |
with neutrons. | 0:08:10 | 0:08:11 | |
One hour later and it's fizzing with radioactivity. | 0:08:31 | 0:08:35 | |
Now, with uranium, gamma ray spectroscopy always shows | 0:08:39 | 0:08:43 | |
these three energy peaks. | 0:08:43 | 0:08:46 | |
This is the unique signature of uranium. | 0:08:46 | 0:08:49 | |
But after bathing our sample in neutrons for an hour, | 0:08:49 | 0:08:52 | |
we get a different picture. | 0:08:52 | 0:08:54 | |
Have a look at this. | 0:08:54 | 0:08:55 | |
Now, in yellow, we get the same three uranium peaks | 0:08:56 | 0:09:00 | |
but we also get a new one. | 0:09:00 | 0:09:02 | |
Because this peak is the characteristic signature, | 0:09:04 | 0:09:07 | |
not of uranium, but of barium. | 0:09:07 | 0:09:09 | |
But the nucleus of a barium atom is about half the weight of uranium. | 0:09:15 | 0:09:20 | |
So, how can a single neutron turn heavy uranium into light barium? | 0:09:23 | 0:09:28 | |
The only possible explanation is if the nucleus of uranium | 0:09:32 | 0:09:36 | |
is splitting into two roughly equal fragments. | 0:09:36 | 0:09:40 | |
What we've done in this lab today is exactly what Otto Hahn | 0:09:40 | 0:09:43 | |
did in his experiment. | 0:09:43 | 0:09:44 | |
We've split the atom. | 0:09:44 | 0:09:46 | |
I believe Otto Hahn's accidental discovery in 1938 | 0:09:51 | 0:09:56 | |
marks the beginning of the nuclear age. | 0:09:56 | 0:09:58 | |
Because his experiment showed that something even more | 0:10:01 | 0:10:04 | |
extraordinary had happened. | 0:10:04 | 0:10:06 | |
The two fragments produced by the uranium nucleus weren't just | 0:10:06 | 0:10:10 | |
falling apart, they were exploding apart with enough | 0:10:10 | 0:10:14 | |
energy from a single nucleus to move a grain of sand. | 0:10:14 | 0:10:19 | |
Now, that may not sound like much, | 0:10:20 | 0:10:22 | |
but imagine how much energy could be produced | 0:10:22 | 0:10:25 | |
if every one of the billion trillion uranium nuclei split in our sample. | 0:10:25 | 0:10:30 | |
Just think what might be possible if this experiment could be scaled up. | 0:10:31 | 0:10:36 | |
Within just four weeks of Hahn splitting the first uranium atom, | 0:10:41 | 0:10:45 | |
a scientist in Washington drew a diagram on a blackboard. | 0:10:45 | 0:10:49 | |
The diagram was of a new kind of weapon, | 0:10:49 | 0:10:51 | |
and the scientist was Robert Oppenheimer. | 0:10:51 | 0:10:55 | |
The creator of the atomic bomb. | 0:10:55 | 0:10:58 | |
Six years later, his nuclear weapons brought the Second World War | 0:11:05 | 0:11:10 | |
to an abrupt end. | 0:11:10 | 0:11:11 | |
So where did that leave Britain? | 0:11:14 | 0:11:16 | |
If it was to be a superpower alongside America and Russia, | 0:11:18 | 0:11:22 | |
it needed a bomb of its own. | 0:11:22 | 0:11:23 | |
So, far away from prying eyes, deep in the Cumbrian countryside, near a | 0:11:29 | 0:11:34 | |
hamlet called Sellafield, plans were afoot to join the nuclear arms race. | 0:11:34 | 0:11:40 | |
In fact, the government first built all of this as a top secret | 0:11:45 | 0:11:50 | |
military research facility. | 0:11:50 | 0:11:52 | |
It was called Windscale. | 0:11:52 | 0:11:54 | |
And its aim - to make plutonium for a British atom bomb. | 0:11:55 | 0:12:00 | |
In here is the prize the Windscale scientists were after. | 0:12:03 | 0:12:07 | |
This is plutonium. | 0:12:08 | 0:12:10 | |
Just like uranium, when atoms of plutonium split or fission, | 0:12:10 | 0:12:14 | |
they release a massive burst of energy. | 0:12:14 | 0:12:16 | |
But there's a catch. | 0:12:20 | 0:12:21 | |
Virtually the only way plutonium can be made is out of uranium | 0:12:22 | 0:12:28 | |
in a nuclear reactor. | 0:12:28 | 0:12:30 | |
So, for four straight years, 5,000 people toiled day and night | 0:12:41 | 0:12:46 | |
to build one. | 0:12:46 | 0:12:48 | |
The science was so new and experimental that the plans | 0:12:53 | 0:12:57 | |
would change almost daily. | 0:12:57 | 0:12:59 | |
But despite this, in October 1950, just ten days behind schedule... | 0:13:06 | 0:13:11 | |
..the Windscale nuclear reactor was finished. | 0:13:13 | 0:13:17 | |
This is the heart of it. | 0:13:38 | 0:13:41 | |
Otto Hahn's experiment on a massive scale. | 0:13:41 | 0:13:44 | |
This is the reactor itself. | 0:13:48 | 0:13:50 | |
Over 20 metres high... | 0:13:50 | 0:13:54 | |
weighing over 2,000 tonnes... | 0:13:54 | 0:13:58 | |
containing over 70,000 uranium rods. | 0:13:58 | 0:14:02 | |
Inside this reactor, the scientists hoped to turn uranium into | 0:14:05 | 0:14:10 | |
plutonium for their bomb. | 0:14:10 | 0:14:12 | |
But to do that, they needed to trigger a chain reaction. | 0:14:14 | 0:14:17 | |
Inside this box are 120 primed mouse traps, | 0:14:21 | 0:14:25 | |
each one with a ping-pong ball on top. | 0:14:25 | 0:14:28 | |
Let's see what happens when I drop this single ball in the top. | 0:14:28 | 0:14:32 | |
One ball triggers more and more mouse traps. | 0:14:40 | 0:14:43 | |
This is a chain reaction. | 0:14:44 | 0:14:46 | |
The Windscale scientists believed their reactor would trigger | 0:14:50 | 0:14:53 | |
a chain reaction, that, in the process, | 0:14:53 | 0:14:56 | |
would turn some of the uranium into plutonium. | 0:14:56 | 0:14:59 | |
As each uranium atom splits, it also releases neutrons. | 0:15:01 | 0:15:05 | |
And just like the ping-pong balls triggering the mouse traps, | 0:15:07 | 0:15:10 | |
these neutrons could split new uranium atoms. | 0:15:10 | 0:15:14 | |
So, if they got it right, the uranium would trigger a massive | 0:15:16 | 0:15:20 | |
nuclear chain reaction, producing enough neutrons to turn some | 0:15:20 | 0:15:25 | |
of the uranium into plutonium for the bomb. | 0:15:25 | 0:15:28 | |
Very nice. That's the genius of the chain reaction. | 0:15:33 | 0:15:37 | |
That was the theory, but nobody knew for sure if it would actually work. | 0:15:38 | 0:15:43 | |
The development work that should have been done was all cut | 0:15:45 | 0:15:51 | |
short by the extreme political and military pressure on them, | 0:15:51 | 0:15:55 | |
the very, very tight deadlines they were given. | 0:15:55 | 0:15:59 | |
You did feel that we were in the vanguard of being something | 0:15:59 | 0:16:05 | |
really new. | 0:16:05 | 0:16:06 | |
Everybody was on a learning curve there, really, from, you know, | 0:16:06 | 0:16:10 | |
ground floor to top level. | 0:16:10 | 0:16:13 | |
In October 1950, the Windscale reactor was finally started up. | 0:16:17 | 0:16:22 | |
This was the moment of truth. | 0:16:31 | 0:16:33 | |
Inside the reactor, the chain reaction began. | 0:16:39 | 0:16:43 | |
It worked. | 0:16:45 | 0:16:46 | |
In the space of just four years, we'd gone from a basic | 0:16:46 | 0:16:49 | |
understanding of nuclear fission to a working nuclear reactor. | 0:16:49 | 0:16:53 | |
The uranium started to turn into plutonium. | 0:16:57 | 0:17:00 | |
But, frustratingly, the process was agonisingly slow. | 0:17:02 | 0:17:06 | |
It took six months in the reactor until there was enough | 0:17:08 | 0:17:11 | |
plutonium to begin to extract it. | 0:17:11 | 0:17:14 | |
I broke down the reaction vessel myself, scrambled around | 0:17:17 | 0:17:20 | |
amongst calcium fluoride, to see if I could find anything. | 0:17:20 | 0:17:23 | |
And there I found a piece of plutonium about this size, about | 0:17:23 | 0:17:27 | |
the size of a 50p piece, 132 grams, and that was our very first piece. | 0:17:27 | 0:17:33 | |
But by 1952, they'd managed to get enough to make | 0:17:38 | 0:17:42 | |
the first British nuclear weapon. | 0:17:42 | 0:17:44 | |
And it was detonated in Montebello Island | 0:17:57 | 0:17:59 | |
in Western Australia. | 0:17:59 | 0:18:01 | |
That lethal cloud, rising above Montebello, | 0:18:04 | 0:18:06 | |
marks the achievement of British science and industry. | 0:18:06 | 0:18:10 | |
At last, Britain had entered the nuclear age. | 0:18:10 | 0:18:13 | |
These weapons had revealed just how much energy there was | 0:18:16 | 0:18:19 | |
within the atom. | 0:18:19 | 0:18:21 | |
But for the nuclear physicists there was another realisation, | 0:18:24 | 0:18:27 | |
that the same science that had split the atom | 0:18:27 | 0:18:30 | |
and produced the bomb could also be used for the betterment of humanity. | 0:18:30 | 0:18:35 | |
That it also had the potential to produce almost limitless | 0:18:35 | 0:18:38 | |
cheap energy, energy to power our cities, light our homes | 0:18:38 | 0:18:43 | |
and forge a secure future for everyone. | 0:18:43 | 0:18:45 | |
Because as well as producing plutonium, the reactor produced | 0:18:47 | 0:18:51 | |
heat, and that heat could be harnessed. | 0:18:51 | 0:18:54 | |
The dream was that the power of the atom would come out of the | 0:18:58 | 0:19:01 | |
shadow of the bomb and into our living rooms... | 0:19:01 | 0:19:05 | |
..as electricity. | 0:19:07 | 0:19:09 | |
And, once again, Sellafield was at the very heart of the story. | 0:19:12 | 0:19:16 | |
Here, in 1952, work began on an ambitious experiment in power | 0:19:18 | 0:19:23 | |
generation that would shape the modern world. | 0:19:23 | 0:19:26 | |
It was called Calder Hall. | 0:19:30 | 0:19:33 | |
And when it opened in 1956, the nation celebrated. | 0:19:36 | 0:19:40 | |
This new power which has proved itself to be such a terrifying | 0:19:43 | 0:19:47 | |
weapon of destruction is harnessed for the first time, | 0:19:47 | 0:19:52 | |
for the common good of our community. | 0:19:52 | 0:19:55 | |
This is the control room of Calder Hall Reactor One, | 0:19:57 | 0:20:01 | |
the nerve centre | 0:20:01 | 0:20:02 | |
of the world's first commercial nuclear power station. | 0:20:02 | 0:20:05 | |
On the 27th of August, 1956, | 0:20:05 | 0:20:08 | |
heat generated from a nuclear chain reaction | 0:20:08 | 0:20:11 | |
was used to turn water into steam, | 0:20:11 | 0:20:14 | |
which drove a turbine that generated electricity. | 0:20:14 | 0:20:17 | |
That electricity now poured into the National Grid. | 0:20:17 | 0:20:21 | |
Britain had become a nuclear-powered nation. | 0:20:21 | 0:20:24 | |
Within ten years, | 0:20:32 | 0:20:34 | |
eight new nuclear power stations were turned on across the country. | 0:20:34 | 0:20:38 | |
Puffed up with scientific zeal, | 0:20:40 | 0:20:42 | |
politicians announced that nuclear power was so cheap | 0:20:42 | 0:20:46 | |
they wouldn't even bother metering the electricity. | 0:20:46 | 0:20:49 | |
At its peak, Calder Hall provided enough electricity | 0:20:53 | 0:20:56 | |
to supply hundreds of thousands of homes. | 0:20:56 | 0:20:59 | |
Today, I'm being allowed inside Calder Hall. | 0:21:06 | 0:21:10 | |
I'm about to see something that as a theoretical physicist | 0:21:11 | 0:21:14 | |
I've only ever imagined, | 0:21:14 | 0:21:16 | |
the core of a nuclear reactor, where the uranium rods actually sit. | 0:21:16 | 0:21:21 | |
Well, I'm at the heart of Calder Hall Reactor One | 0:21:25 | 0:21:29 | |
and down here... | 0:21:29 | 0:21:32 | |
beneath my feet is the core itself. | 0:21:32 | 0:21:34 | |
'Just ten metres below me are thousands of radioactive | 0:21:36 | 0:21:40 | |
'uranium fuel rods.' | 0:21:40 | 0:21:42 | |
SIREN | 0:21:43 | 0:21:45 | |
'I'm with the inspection team | 0:21:49 | 0:21:51 | |
'that's going to check the state of these fuel rods, | 0:21:51 | 0:21:54 | |
'and that means opening up the core itself.' | 0:21:54 | 0:21:57 | |
So, what exactly will we see today? | 0:21:58 | 0:22:01 | |
-When I take the blank off... -Right. | 0:22:01 | 0:22:03 | |
..and then we'll take the shield plug out, | 0:22:03 | 0:22:05 | |
put a spiral camera down and you'll be able to see into the reactor. | 0:22:05 | 0:22:08 | |
What sort of things do you hope to see with the camera? | 0:22:08 | 0:22:10 | |
Top of the fuel elements. | 0:22:10 | 0:22:13 | |
To make sure that there's no nasties in there. | 0:22:13 | 0:22:15 | |
That's right, yeah, there's no obstructions or anything like that. | 0:22:15 | 0:22:18 | |
I'm, I'm feeling the, | 0:22:20 | 0:22:21 | |
the usual combination of excitement and nervousness. | 0:22:21 | 0:22:25 | |
Right, so we should get out of the way now? | 0:22:27 | 0:22:28 | |
-Er, yes! -Right, OK! | 0:22:28 | 0:22:31 | |
This is the protective shield plug | 0:22:36 | 0:22:38 | |
that sits just above the core itself. | 0:22:38 | 0:22:41 | |
This reactor was shut down 12 years ago, | 0:22:42 | 0:22:45 | |
but despite that the core is still hot, | 0:22:45 | 0:22:48 | |
with radioactivity, which they monitor closely. | 0:22:48 | 0:22:51 | |
DISTANT SIREN | 0:22:52 | 0:22:54 | |
-When the plug came out... -INDISTINCT | 0:22:54 | 0:22:57 | |
..gamma, beta-gamma. | 0:22:57 | 0:22:58 | |
That's something like, I guess how much, | 0:22:58 | 0:23:01 | |
a dose you'd get from a C-Scan or something like that. | 0:23:01 | 0:23:03 | |
-That's your dose for the year. -Your dose for a year in one... -Yeah. | 0:23:03 | 0:23:07 | |
-OK, right. -Yeah. -So, still... | 0:23:07 | 0:23:09 | |
-Still a... -..full of radioactivity there. | 0:23:09 | 0:23:12 | |
SIREN CONTINUES | 0:23:12 | 0:23:14 | |
The team also regularly monitors the physical state of the rods. | 0:23:14 | 0:23:19 | |
'And the only way to do that is by remote control camera.' | 0:23:19 | 0:23:24 | |
This is us going down through standpipe, | 0:23:24 | 0:23:27 | |
heading down into the reactor floor. | 0:23:27 | 0:23:29 | |
-It's a long way down. -Yeah, it's 20 feet. | 0:23:29 | 0:23:31 | |
DISTANT SIREN | 0:23:31 | 0:23:32 | |
OK, Robert, can we stop there? | 0:23:35 | 0:23:37 | |
Whoa. Here are the channels. | 0:23:37 | 0:23:39 | |
-Those are the channels within the standpipe. -Yeah. | 0:23:39 | 0:23:41 | |
And each channel, that's where the fuel rods... | 0:23:41 | 0:23:44 | |
That's where the fuel rod is | 0:23:44 | 0:23:45 | |
and there's either five or six fuel elements in each channel. | 0:23:45 | 0:23:49 | |
The flashes on the picture | 0:23:49 | 0:23:50 | |
are the effects of the powerful radiation on the camera. | 0:23:50 | 0:23:54 | |
Just here, | 0:23:54 | 0:23:55 | |
that's the glimmer of the top of a fuel element you can just see there. | 0:23:55 | 0:23:59 | |
Just about see them shining. | 0:23:59 | 0:24:02 | |
Eventually, all these uranium fuel rods will be removed. | 0:24:03 | 0:24:08 | |
Not many people get to look down into a reactor core | 0:24:08 | 0:24:12 | |
staring at a fuel rod. | 0:24:12 | 0:24:13 | |
BIRDS TWEET | 0:24:18 | 0:24:20 | |
Calder Hall has, without doubt, been a scientific success story. | 0:24:21 | 0:24:26 | |
It proved that nuclear power really worked. | 0:24:27 | 0:24:30 | |
But just over a year after it opened, | 0:24:34 | 0:24:37 | |
this age of optimism came to an end. | 0:24:37 | 0:24:40 | |
The nuclear forces that Otto Hahn unleashed back in 1938 | 0:24:44 | 0:24:48 | |
had unexpected consequences. | 0:24:48 | 0:24:51 | |
Inside the Pandora's box of the atomic nucleus, | 0:24:51 | 0:24:54 | |
along with the hope of unlimited energy, | 0:24:54 | 0:24:57 | |
-was a dark secret... -MUFFLED SIREN | 0:24:57 | 0:24:59 | |
..that these forces were hard to control. | 0:24:59 | 0:25:02 | |
And this became terrifyingly apparent | 0:25:04 | 0:25:07 | |
in the Windscale fire of 1957. | 0:25:07 | 0:25:10 | |
Monday, 7th of October, | 0:25:15 | 0:25:18 | |
the Windscale reactor was shut down for routine maintenance. | 0:25:18 | 0:25:21 | |
But then, something strange happened. | 0:25:23 | 0:25:26 | |
Instead of cooling, the temperature inside started to rise. | 0:25:27 | 0:25:31 | |
My grandfather was part of the team working here. Um... | 0:25:33 | 0:25:37 | |
the evidence and the information that was being relayed to them | 0:25:37 | 0:25:40 | |
indicated something was amiss. | 0:25:40 | 0:25:42 | |
I walked up on to the top of the pile | 0:25:44 | 0:25:49 | |
and I saw a monitor up there | 0:25:49 | 0:25:52 | |
and he said, "It's too hot. There's too much radiation." | 0:25:52 | 0:25:57 | |
Eventually, someone peered into the core itself | 0:25:58 | 0:26:01 | |
from a hole at the top of the reactor just here. | 0:26:01 | 0:26:05 | |
They saw something no-one had ever considered possible. | 0:26:05 | 0:26:09 | |
The core itself was on fire. | 0:26:09 | 0:26:11 | |
I got a phone call from the General Manager. | 0:26:13 | 0:26:16 | |
He said, "Tom, Pile One's on fire." | 0:26:16 | 0:26:18 | |
I said, "Good God, you don't mean the core?" | 0:26:18 | 0:26:21 | |
He said, "Yes." | 0:26:21 | 0:26:22 | |
And we didn't know what we could do to stop it. | 0:26:22 | 0:26:25 | |
DISTANT ALARM | 0:26:25 | 0:26:26 | |
The fire raged for three days. | 0:26:26 | 0:26:29 | |
Workers risked terrible radiation burns trying to push the fuel | 0:26:29 | 0:26:33 | |
out of the reactor, using anything they could lay their hands on. | 0:26:33 | 0:26:37 | |
But despite this, the fire continued to burn. | 0:26:37 | 0:26:41 | |
So, they came up with a new plan... | 0:26:41 | 0:26:44 | |
they'd flood the core | 0:26:44 | 0:26:46 | |
and turn off the cooling fans. | 0:26:46 | 0:26:50 | |
It was a huge risk. | 0:26:50 | 0:26:52 | |
If you look at the size of the reactor face, | 0:26:52 | 0:26:54 | |
each one of these tubes has fuel in, | 0:26:54 | 0:26:56 | |
so the risk of setting them all on fire is immense. | 0:26:56 | 0:27:00 | |
If they were wrong, the whole reactor might explode. | 0:27:00 | 0:27:06 | |
You've got this blazing inferno | 0:27:06 | 0:27:07 | |
with these flames belting out and hitting the back wall. | 0:27:07 | 0:27:11 | |
Mankind had not faced anything like this ever before. | 0:27:11 | 0:27:15 | |
-ALARM -They had no alternative. | 0:27:15 | 0:27:19 | |
They hit the switch. | 0:27:19 | 0:27:21 | |
The air goes off and psst... | 0:27:24 | 0:27:27 | |
just like that. | 0:27:27 | 0:27:28 | |
Absolutely incredible. | 0:27:28 | 0:27:30 | |
The fire was finally out. | 0:27:32 | 0:27:34 | |
But a new danger became apparent. | 0:27:36 | 0:27:39 | |
Flames had melted the casing surrounding the nuclear fuel | 0:27:42 | 0:27:46 | |
and some of the elements had burst. | 0:27:46 | 0:27:48 | |
Radioactive material escaped out and up the chimney. | 0:27:48 | 0:27:52 | |
A cloud of smoke began to fall over the area. | 0:27:52 | 0:27:57 | |
As the wind blew it eastwards, it seemed catastrophic. | 0:27:57 | 0:28:02 | |
Thousands of square miles might be contaminated. | 0:28:02 | 0:28:05 | |
Hundreds of people could die. | 0:28:05 | 0:28:07 | |
But it didn't happen. | 0:28:10 | 0:28:13 | |
Thanks to one man. | 0:28:13 | 0:28:14 | |
I'm now in the lift, climbing the 120-metre high chimney | 0:28:26 | 0:28:31 | |
that was built to release the air | 0:28:31 | 0:28:33 | |
used to cool the nuclear pile down below. | 0:28:33 | 0:28:36 | |
Now, at the time, no-one imagined that releasing this air | 0:28:36 | 0:28:39 | |
out into the atmosphere was in any way hazardous. | 0:28:39 | 0:28:42 | |
Well, almost no-one. | 0:28:42 | 0:28:44 | |
Seven years earlier, the Windscale Project had been masterminded | 0:28:50 | 0:28:54 | |
by a physicist called John Cockcroft. | 0:28:54 | 0:28:57 | |
He'd made his name in 1932, | 0:28:57 | 0:29:00 | |
when he'd knocked together the world's first atomic accelerator. | 0:29:00 | 0:29:03 | |
It was made out of packing cases and tinfoil | 0:29:03 | 0:29:06 | |
and eventually won him the Nobel Prize. | 0:29:06 | 0:29:08 | |
After this chimney was built, Cockcroft had a moment of doubt. | 0:29:15 | 0:29:19 | |
What if the cooling air became contaminated? | 0:29:19 | 0:29:22 | |
Now, no-one on his team believed this could actually happen, | 0:29:22 | 0:29:26 | |
but Cockcroft was intransigent. | 0:29:26 | 0:29:28 | |
He demanded that his engineers build a filter here | 0:29:28 | 0:29:31 | |
at the very top of the 120-metre chimney. | 0:29:31 | 0:29:35 | |
They laughingly called his idea "Cockcroft's Folly." | 0:29:35 | 0:29:39 | |
Of course, he got his way. | 0:29:40 | 0:29:42 | |
You can still see where the filters were slotted in | 0:29:42 | 0:29:45 | |
across the top of the open chimney. | 0:29:45 | 0:29:48 | |
As the cloud from the fire below belched out of the chimney, | 0:29:49 | 0:29:53 | |
Cockcroft's Folly trapped almost all of the radioactivity. | 0:29:53 | 0:29:58 | |
Designed by a maverick genius, built on a whim, this basic filter | 0:30:02 | 0:30:07 | |
saved the North West and beyond from a terrible fate. | 0:30:07 | 0:30:10 | |
This was the world's first nuclear accident | 0:30:19 | 0:30:22 | |
and it served as a powerful warning that harvesting nuclear energy | 0:30:22 | 0:30:27 | |
could lead to some unexpected and potentially lethal consequences. | 0:30:27 | 0:30:33 | |
In the decades that have followed, | 0:30:33 | 0:30:35 | |
there have been other more serious incidents at nuclear plants | 0:30:35 | 0:30:38 | |
around the world. | 0:30:38 | 0:30:40 | |
Three Mile Island, | 0:30:41 | 0:30:44 | |
Chernobyl | 0:30:44 | 0:30:45 | |
and Fukushima. | 0:30:45 | 0:30:46 | |
Now, terms like contamination and radioactive leak | 0:30:51 | 0:30:55 | |
are for ever etched in the public consciousness. | 0:30:55 | 0:30:58 | |
I think what haunts us about radioactivity | 0:31:02 | 0:31:05 | |
is that it's invisible, | 0:31:05 | 0:31:08 | |
it's intangible | 0:31:08 | 0:31:10 | |
and sometimes deadly. | 0:31:10 | 0:31:13 | |
At Sellafield itself, it's something of an obsession. | 0:31:13 | 0:31:16 | |
BELL RINGS | 0:31:16 | 0:31:18 | |
Every time I leave a building, | 0:31:18 | 0:31:21 | |
I'm checked and re-checked for any signs of radioactive contamination. | 0:31:21 | 0:31:26 | |
But what exactly is radioactivity? | 0:31:28 | 0:31:31 | |
Radioactivity is, in fact, three different processes, | 0:31:32 | 0:31:36 | |
each one dangerous in its own particular way. | 0:31:36 | 0:31:38 | |
They're called alpha, beta and gamma. | 0:31:38 | 0:31:41 | |
Let me show you with this radioactive source. | 0:31:41 | 0:31:44 | |
Now, this is a mineral called pitch blend | 0:31:44 | 0:31:46 | |
which emits all three types of radioactivity. | 0:31:46 | 0:31:49 | |
The first type is alpha radiation. | 0:31:49 | 0:31:52 | |
Now, these are the emission of tiny lumps of nuclear matter | 0:31:52 | 0:31:56 | |
made up of two protons and two neutrons called alpha particles. | 0:31:56 | 0:32:00 | |
They're spat out from a nucleus, like uranium. | 0:32:00 | 0:32:03 | |
Now, alpha radiation is very short-ranged | 0:32:03 | 0:32:06 | |
so I have to bring this detector very close to the source | 0:32:06 | 0:32:09 | |
to pick them up. | 0:32:09 | 0:32:11 | |
And even a thin sheet of paper will stop them almost completely. | 0:32:13 | 0:32:18 | |
Of course, alpha radiation is still dangerous | 0:32:18 | 0:32:21 | |
when it comes into contact with skin | 0:32:21 | 0:32:23 | |
or if you breathe it in or ingest it. | 0:32:23 | 0:32:25 | |
The second type of radioactivity is called beta radiation. | 0:32:25 | 0:32:29 | |
Now, these are tiny particles, electrons, | 0:32:29 | 0:32:31 | |
or their cousins, the positrons, | 0:32:31 | 0:32:33 | |
that are spat out of a nucleus at very high speed. | 0:32:33 | 0:32:36 | |
When I switch my detector to beta radiation, | 0:32:39 | 0:32:42 | |
we see that these particles are more penetrating, | 0:32:42 | 0:32:45 | |
passing straight through paper... | 0:32:45 | 0:32:47 | |
..but a sheet of aluminium blocks them. | 0:32:49 | 0:32:52 | |
But beta radiation is also very dangerous - | 0:32:55 | 0:32:58 | |
in fact, if exposed to it, it can burn the skin. | 0:32:58 | 0:33:01 | |
Beta particles can even penetrate the skin | 0:33:01 | 0:33:03 | |
and burn the tissue beneath. | 0:33:03 | 0:33:05 | |
The third type is gamma radioactivity. | 0:33:06 | 0:33:08 | |
Now, this is the emission not of particles of matter at all, | 0:33:08 | 0:33:12 | |
but tiny lumps of light - | 0:33:12 | 0:33:14 | |
high energy photons that fly out from the nucleus. | 0:33:14 | 0:33:17 | |
Now when I look for gamma radiation, | 0:33:20 | 0:33:22 | |
I see it passes easily through the aluminium, | 0:33:22 | 0:33:25 | |
but a sheet of dense metal like lead effectively blocks them. | 0:33:25 | 0:33:29 | |
To show you just how damaging gamma radioactivity can be, | 0:33:33 | 0:33:36 | |
I've got these two plants. | 0:33:36 | 0:33:38 | |
Now, one I'm going to place safely out here | 0:33:38 | 0:33:40 | |
and the other inside this radiation furnace. | 0:33:40 | 0:33:44 | |
This will blast the plant with a huge radiation dose - | 0:33:47 | 0:33:52 | |
about the same as that given off by a spent nuclear fuel rod. | 0:33:52 | 0:33:56 | |
Within minutes, the powerful radiation starts to affect the plant | 0:34:02 | 0:34:07 | |
and our camera. | 0:34:07 | 0:34:08 | |
The white snow is due to the radiation striking the camera's sensor. | 0:34:10 | 0:34:14 | |
After an hour, the plant is transformed. | 0:34:26 | 0:34:30 | |
Oh, wow! | 0:34:30 | 0:34:32 | |
Look at that - | 0:34:32 | 0:34:34 | |
the leaves are hanging limply, some of the flowers have fallen off. | 0:34:34 | 0:34:38 | |
Compared with the healthy specimen, that looks a real mess. | 0:34:38 | 0:34:42 | |
Under the microscope, | 0:34:47 | 0:34:49 | |
we can see the damage done to the irradiated sample. | 0:34:49 | 0:34:51 | |
Now, this is what a healthy sample should look like - | 0:34:51 | 0:34:56 | |
beautiful, clearly defined cells, nice clean cell walls. | 0:34:56 | 0:35:01 | |
And here is our irradiated sample - | 0:35:01 | 0:35:05 | |
the cells are burnt, the cell walls have been damaged... | 0:35:05 | 0:35:09 | |
and all this from just radioactivity. | 0:35:09 | 0:35:12 | |
It explodes as energy... | 0:35:16 | 0:35:19 | |
In the 1960s and '70s, | 0:35:19 | 0:35:22 | |
public understanding about the effects of radioactivity grew... | 0:35:22 | 0:35:26 | |
..and so, too, did their unease with the nuclear industry itself. | 0:35:27 | 0:35:32 | |
The cosy, optimistic, clean image of the '50s had changed. | 0:35:32 | 0:35:38 | |
Hey, hold it! | 0:35:38 | 0:35:40 | |
But the government kept faith with the nuclear programme | 0:35:40 | 0:35:43 | |
and pushed ahead. | 0:35:43 | 0:35:45 | |
Here at Sellafield, they built the Windscale Advanced Gas Reactor | 0:35:46 | 0:35:53 | |
and, across the country, there were others - | 0:35:53 | 0:35:55 | |
Chapelcross, | 0:35:55 | 0:35:57 | |
Dungeness, | 0:35:57 | 0:35:58 | |
Sizewell. | 0:35:58 | 0:35:59 | |
By the mid-'70s, over a dozen nuclear power stations | 0:36:01 | 0:36:05 | |
were producing a quarter of Britain's electricity... | 0:36:05 | 0:36:08 | |
..but they were also producing huge amounts of radioactive material. | 0:36:11 | 0:36:15 | |
Virtually all of it was sent here, to Sellafield, for storage. | 0:36:21 | 0:36:26 | |
And as we now know, this is nasty stuff. | 0:36:26 | 0:36:30 | |
So, what on earth were they going to do with it? | 0:36:30 | 0:36:33 | |
Back then, some of it was simply stored deep underwater | 0:36:42 | 0:36:47 | |
in these vast open-air storage ponds. | 0:36:47 | 0:36:49 | |
Hundreds of tonnes of spent fuel rods and radioactive waste | 0:36:51 | 0:36:55 | |
were effectively dumped. | 0:36:55 | 0:36:57 | |
Worryingly, there wasn't a long-term plan for any of it. | 0:36:59 | 0:37:03 | |
By the 1980s, | 0:37:08 | 0:37:10 | |
one of the defining issues for opponents of the nuclear industry | 0:37:10 | 0:37:13 | |
was radioactive waste. | 0:37:13 | 0:37:16 | |
Low-level waste should be the easiest to dispose of. | 0:37:16 | 0:37:20 | |
In fact, it's simply dumped, | 0:37:20 | 0:37:23 | |
left to the rain to leach it away, perhaps into local streams. | 0:37:23 | 0:37:26 | |
Opposition to the nuclear industry grew | 0:37:28 | 0:37:30 | |
over fears about the amounts of radioactive material | 0:37:30 | 0:37:34 | |
they felt was being moved around the country. | 0:37:34 | 0:37:37 | |
By the early '80s, | 0:37:40 | 0:37:41 | |
there was a battle for the hearts and minds of public opinion. | 0:37:41 | 0:37:45 | |
Nuclear power is not safe, not economic, not needed | 0:37:46 | 0:37:50 | |
and certainly not worth the risk. | 0:37:50 | 0:37:52 | |
The focus of the argument was the disposal of nuclear material. | 0:37:53 | 0:37:57 | |
The environmentalists on one side, | 0:37:59 | 0:38:01 | |
trying to stop its movement around the country... | 0:38:01 | 0:38:04 | |
..the nuclear industry on the other... | 0:38:06 | 0:38:08 | |
The flask wasn't significantly damaged... | 0:38:10 | 0:38:12 | |
If they distrust us, we've said, "All right, well, we'll show them." | 0:38:12 | 0:38:16 | |
..going to extreme lengths to try to prove how safe it was | 0:38:16 | 0:38:19 | |
when it was being moved. | 0:38:19 | 0:38:22 | |
But dropping the flask wasn't enough. | 0:38:22 | 0:38:25 | |
It had remained intact and totally safe for the public | 0:38:29 | 0:38:32 | |
had it contained actual radioactive materials. | 0:38:32 | 0:38:35 | |
And all the time, radioactive waste and spent uranium fuel rods | 0:38:42 | 0:38:46 | |
were still arriving at one place - | 0:38:46 | 0:38:50 | |
Sellafield. | 0:38:50 | 0:38:51 | |
It was gaining a reputation as Britain's nuclear dustbin. | 0:38:53 | 0:38:57 | |
Then, on the 18th of November 1983, | 0:38:59 | 0:39:02 | |
something happened here that damaged Sellafield's reputation irrevocably, | 0:39:02 | 0:39:06 | |
so badly, in fact, that many people questioned | 0:39:06 | 0:39:09 | |
whether the plant should be closed down altogether. | 0:39:09 | 0:39:12 | |
That morning, scientists at Sellafield looked out to sea | 0:39:16 | 0:39:19 | |
and saw an inky black slick. | 0:39:19 | 0:39:22 | |
It was a slick of waste pouring out of Sellafield. | 0:39:22 | 0:39:25 | |
Something had gone wrong. | 0:39:27 | 0:39:29 | |
Highly radioactive waste went into this tank by mistake | 0:39:29 | 0:39:32 | |
and much of it was discharged to the sea. | 0:39:32 | 0:39:34 | |
Now, it's easy to point the finger in retrospect | 0:39:36 | 0:39:39 | |
but, without doubt, a certain complacency had set in at Sellafield - | 0:39:39 | 0:39:43 | |
a day-to-day lack of forethought and safety. | 0:39:43 | 0:39:47 | |
Due to basic miscommunication, | 0:39:47 | 0:39:49 | |
stored radioactive water was accidentally released out into the sea. | 0:39:49 | 0:39:53 | |
Suddenly, more than ever before, | 0:39:55 | 0:39:58 | |
their safety record was a matter of public concern. | 0:39:58 | 0:40:01 | |
Greenpeace had been monitoring the discharges when the slick appeared. | 0:40:03 | 0:40:07 | |
They sent the dinghy | 0:40:07 | 0:40:08 | |
to the Government's Radiation Protection Board for tests... | 0:40:08 | 0:40:11 | |
The local environmental pressure group wants Sellafield closed. | 0:40:11 | 0:40:15 | |
This incident appeared to confirm the environmentalists' worst fears - | 0:40:15 | 0:40:20 | |
accidents like this were bound to happen. | 0:40:20 | 0:40:24 | |
The future of Sellafield appeared to hang in the balance. | 0:40:27 | 0:40:31 | |
But, actually, plans were already in place to change the way | 0:40:34 | 0:40:38 | |
they dealt with radioactive waste and the spent fuel rods. | 0:40:38 | 0:40:42 | |
The most ambitious of all... | 0:40:43 | 0:40:47 | |
was this - | 0:40:47 | 0:40:49 | |
the Thermal Oxide Reprocessing Plant, Thorp. | 0:40:49 | 0:40:53 | |
Costing more than £2 billion, it opened in 1994. | 0:41:01 | 0:41:06 | |
It's one of the world's largest nuclear reprocessing plants, | 0:41:07 | 0:41:12 | |
designed to deal with spent fuel rods safely... | 0:41:12 | 0:41:15 | |
..and to commercially extract the uranium from them to be used again. | 0:41:18 | 0:41:22 | |
In the '70s and '80s, when uranium was thought to be scarce, | 0:41:25 | 0:41:29 | |
this was a huge idea | 0:41:29 | 0:41:30 | |
because this uranium can then go back into nuclear power stations. | 0:41:30 | 0:41:34 | |
Reprocessing had been done at Sellafield before | 0:41:37 | 0:41:41 | |
but nothing like on this scale. | 0:41:41 | 0:41:43 | |
This is the receipt pond. | 0:41:46 | 0:41:49 | |
It's here that the spent fuel canisters arrive | 0:41:49 | 0:41:51 | |
from power stations all around the world. | 0:41:51 | 0:41:54 | |
It's in this pond that they're first opened up | 0:41:54 | 0:41:56 | |
and the spent fuel rods removed and then taken to the storage pond. | 0:41:56 | 0:42:01 | |
Then, the empty flasks are lifted up, taken away | 0:42:08 | 0:42:11 | |
and washed to be used again. | 0:42:11 | 0:42:13 | |
Meanwhile, the spent fuel is moved here - | 0:42:22 | 0:42:26 | |
a massive storage pond. | 0:42:26 | 0:42:28 | |
The water acts as a shield, | 0:42:30 | 0:42:32 | |
blocking the radioactivity while it cools down... | 0:42:32 | 0:42:34 | |
..a process that can take up to five years. | 0:42:37 | 0:42:39 | |
Once the fuel rods have cooled down underwater, | 0:42:43 | 0:42:46 | |
they're ready for the reprocessing to take place. | 0:42:46 | 0:42:49 | |
Now, first of all, they have to be monitored because we have | 0:42:49 | 0:42:52 | |
to make sure that they contain what they say on the tin. | 0:42:52 | 0:42:55 | |
These rods come from reactors from all round the world. | 0:42:55 | 0:42:58 | |
Once that's done, they can be taken up through that entry there | 0:43:03 | 0:43:07 | |
into what's called the sheer cave. | 0:43:07 | 0:43:09 | |
Once they're in there, | 0:43:09 | 0:43:11 | |
they're behind two metres-thick concrete walls | 0:43:11 | 0:43:14 | |
and they're beyond any human contact. | 0:43:14 | 0:43:16 | |
Through metre-thick glass, | 0:43:19 | 0:43:21 | |
you can see the machinery used to cut up the rods | 0:43:21 | 0:43:24 | |
before being dissolved into boiling nitric acid. | 0:43:24 | 0:43:29 | |
The next stage is to extract the pure uranium. | 0:43:35 | 0:43:38 | |
Each one of these machines is an agitator | 0:43:40 | 0:43:42 | |
and it just has a stirrer on the bottom | 0:43:42 | 0:43:44 | |
which mixes up the nitric acid feed with the solvent. | 0:43:44 | 0:43:47 | |
In my plant, the uranium is contacted with solvent | 0:43:47 | 0:43:51 | |
and we get just pure uranium. | 0:43:51 | 0:43:54 | |
The entirety of my system happens behind two metres of concrete. | 0:43:54 | 0:43:57 | |
I can never touch or never go anywhere near the vessels in my system. | 0:43:57 | 0:44:01 | |
The actual equipment attached to this motor is metres beneath me, | 0:44:01 | 0:44:04 | |
in a tank that, until we decommission the plant, | 0:44:04 | 0:44:07 | |
no-one will ever see again. | 0:44:07 | 0:44:09 | |
Thorp reclaims the uranium as well as plutonium | 0:44:11 | 0:44:15 | |
from the spent fuel, so that it can be used again. | 0:44:15 | 0:44:18 | |
This isn't disposal - it's reprocessing. | 0:44:20 | 0:44:23 | |
Thorp gave a much-needed boost to Sellafield. | 0:44:26 | 0:44:31 | |
Attitudes to safety appeared very different from the '70s and '80s. | 0:44:31 | 0:44:36 | |
It seemed to be taking waste management seriously. | 0:44:36 | 0:44:39 | |
But although 97% of the spent nuclear fuel is recycled | 0:44:48 | 0:44:52 | |
here at Sellafield, that still leaves 3% as waste... | 0:44:52 | 0:44:57 | |
..and that 3% is a problem | 0:44:59 | 0:45:01 | |
because it's very, very toxic. | 0:45:01 | 0:45:05 | |
When Otto Hahn carried out his experiment in 1938, | 0:45:10 | 0:45:14 | |
his fissioned uranium famously produced barium, | 0:45:14 | 0:45:18 | |
but there were other products, too - | 0:45:18 | 0:45:20 | |
krypton, strontium, caesium, iodine, xenon | 0:45:20 | 0:45:24 | |
and exotic heavy metals like americium, berkelium and curium. | 0:45:24 | 0:45:29 | |
Some of these are powerfully radioactive, | 0:45:29 | 0:45:32 | |
others have half-lives of thousands or hundreds of thousands of years. | 0:45:32 | 0:45:36 | |
This cocktail is the most toxic end product | 0:45:36 | 0:45:39 | |
of the entire nuclear industry. | 0:45:39 | 0:45:42 | |
This nuclear waste is so dangerous | 0:45:46 | 0:45:49 | |
that exposure to it would kill you within hours. | 0:45:49 | 0:45:52 | |
In the '90s, Sellafield designed a process that - | 0:45:57 | 0:46:01 | |
while it wouldn't render it harmless - | 0:46:01 | 0:46:04 | |
would at least lock it away. | 0:46:04 | 0:46:05 | |
Currently, this is the end of the road | 0:46:07 | 0:46:10 | |
for this foul and dangerous stuff. | 0:46:10 | 0:46:12 | |
To render it safe and stable, it's vitrified, | 0:46:12 | 0:46:16 | |
which means it's encased in glass, | 0:46:16 | 0:46:18 | |
and that process takes place in here... | 0:46:18 | 0:46:21 | |
..albeit behind a metre of lead glass | 0:46:27 | 0:46:30 | |
that shields me from the intense radiation. | 0:46:30 | 0:46:33 | |
The process is simple enough - | 0:46:33 | 0:46:35 | |
the highly radioactive waste is first dried to a powder. | 0:46:35 | 0:46:40 | |
It looks a bit like this, strangely like coffee granules. | 0:46:40 | 0:46:43 | |
Then, glass granules are added to the mixture | 0:46:43 | 0:46:46 | |
and it's heated to about 1,100 degrees. | 0:46:46 | 0:46:49 | |
It melts and is poured into those containers in there. | 0:46:49 | 0:46:53 | |
Now, the important thing about vitrification | 0:46:53 | 0:46:56 | |
is that it then solidifies as it cools | 0:46:56 | 0:46:59 | |
so there's no chance of leakage. | 0:46:59 | 0:47:01 | |
It looks a little bit like this. | 0:47:01 | 0:47:03 | |
So, the radioactive waste is now not encased in the glass, | 0:47:03 | 0:47:07 | |
it becomes part of the glass itself. | 0:47:07 | 0:47:10 | |
Those containers are then sealed, they're decontaminated | 0:47:10 | 0:47:14 | |
and taken away for storage. | 0:47:14 | 0:47:16 | |
And this is where the containers of vitrified waste are brought. | 0:47:18 | 0:47:22 | |
Under this floor, they're stacked up to ten deep. | 0:47:22 | 0:47:26 | |
They're air-cooled and monitored 24 hours a day. | 0:47:26 | 0:47:29 | |
The radiation produced by the waste down below is so intense, | 0:47:33 | 0:47:37 | |
it produces heat that I can feel up here on the surface, | 0:47:37 | 0:47:40 | |
even though I'm shielded by over two metres of concrete. | 0:47:40 | 0:47:44 | |
This is where several thousand tonnes of the most toxic waste in the world is stored, | 0:47:44 | 0:47:51 | |
and here is where it'll currently remain. | 0:47:51 | 0:47:53 | |
But, ultimately, what makes this nuclear waste so deadly | 0:47:57 | 0:48:01 | |
is not just the high level of radioactivity, | 0:48:01 | 0:48:04 | |
but the length of time it remains that way. | 0:48:04 | 0:48:07 | |
Every isotope is different - | 0:48:11 | 0:48:14 | |
some are active for just seconds, | 0:48:14 | 0:48:16 | |
others remain radioactive for millions of years. | 0:48:16 | 0:48:19 | |
This facet of their character | 0:48:19 | 0:48:21 | |
is captured by something called the half-life. | 0:48:21 | 0:48:24 | |
SIREN BLARES | 0:48:24 | 0:48:26 | |
To show you what I mean, I've set up an experiment. | 0:48:31 | 0:48:35 | |
I'm bombarding a sample of quartz with a proton beam. | 0:48:35 | 0:48:39 | |
This will make it radioactive. | 0:48:40 | 0:48:42 | |
It's produced an isotope of nitrogen that is radioactive. | 0:48:48 | 0:48:51 | |
It's producing beta particles | 0:48:51 | 0:48:53 | |
and these are counted by this device here. | 0:48:53 | 0:48:56 | |
Now, to give you an idea of what a half-life means, | 0:48:56 | 0:48:59 | |
I'm going to record the activity every minute for half an hour. | 0:48:59 | 0:49:04 | |
OK, so it's now showing that 1,400 beta particles per second | 0:49:04 | 0:49:08 | |
are being emitted. | 0:49:08 | 0:49:10 | |
So, that's 1,150 counts after one minute. | 0:49:12 | 0:49:16 | |
Dropping right down. | 0:49:22 | 0:49:24 | |
Now down to just under 700 after five minutes. | 0:49:24 | 0:49:27 | |
So, here's what my graph tells me. | 0:49:33 | 0:49:36 | |
My sample started off with a count rate of 1,400 per second. | 0:49:36 | 0:49:41 | |
After eight or nine minutes, that had dropped by a half | 0:49:41 | 0:49:44 | |
and then by a further half after another nine minutes. | 0:49:44 | 0:49:47 | |
This period of time over which the count rate drops by a half | 0:49:47 | 0:49:51 | |
is called the half-life. | 0:49:51 | 0:49:54 | |
And this is important because, unlike my sample - | 0:49:54 | 0:49:58 | |
which has a half-life of nine minutes - | 0:49:58 | 0:50:00 | |
some of the material at Sellafield | 0:50:00 | 0:50:02 | |
has a half-life of hundreds of thousands of years. | 0:50:02 | 0:50:05 | |
In other words, it won't be safe for thousands of generations. | 0:50:07 | 0:50:11 | |
And this means that much of the work here is now about finding ways | 0:50:15 | 0:50:19 | |
to store this material safely for a very long time. | 0:50:19 | 0:50:23 | |
In the early days, they built nuclear reactors | 0:50:32 | 0:50:35 | |
with little thought of what to do when they came to the end of their working lives. | 0:50:35 | 0:50:40 | |
For instance, this experimental reactor built here at Sellafield in the '60s | 0:50:43 | 0:50:48 | |
was finally shut down in 1981. | 0:50:48 | 0:50:50 | |
Sellafield decommissioned this core by building a giant robotic arm | 0:50:52 | 0:50:57 | |
that reached inside and cut it up into fragments. | 0:50:57 | 0:51:01 | |
It then put all those dangerous radioactive pieces | 0:51:01 | 0:51:03 | |
into large steel reinforced concrete boxes. | 0:51:03 | 0:51:07 | |
And those boxes are stored here at Sellafield, | 0:51:13 | 0:51:16 | |
in this air-conditioned warehouse. | 0:51:16 | 0:51:18 | |
This, then, is the decommissioned core of a nuclear reactor. | 0:51:20 | 0:51:25 | |
It's very unnerving hearing the radiation detector | 0:51:29 | 0:51:31 | |
making so much noise. | 0:51:31 | 0:51:33 | |
In fact, these levels are completely safe - | 0:51:33 | 0:51:36 | |
still, it's eerie being so close to something so deadly. | 0:51:36 | 0:51:40 | |
These concrete blocks will contain the radioactivity | 0:51:42 | 0:51:45 | |
until it's relatively harmless, some 100 years from now. | 0:51:45 | 0:51:49 | |
But just across the road | 0:52:03 | 0:52:05 | |
is one of the most controversial problems facing Sellafield today - | 0:52:05 | 0:52:10 | |
cleaning up the waste from the legacy ponds. | 0:52:10 | 0:52:12 | |
This is the First Generation Magnox Storage Pond, | 0:52:15 | 0:52:19 | |
acknowledged by Sellafield themselves | 0:52:19 | 0:52:21 | |
as one of the most dangerous buildings in Western Europe. | 0:52:21 | 0:52:24 | |
And that's because the ponds that nuclear waste was dumped in | 0:52:26 | 0:52:29 | |
for decades are deteriorating. | 0:52:29 | 0:52:33 | |
Contaminated water is seeping through the internal walls. | 0:52:33 | 0:52:36 | |
Sellafield's current plan is to remove the waste | 0:52:39 | 0:52:42 | |
from these ageing ponds, mix it with concrete | 0:52:42 | 0:52:45 | |
and then store it in steel containers. | 0:52:45 | 0:52:47 | |
They're already using a remote-controlled vehicle | 0:52:51 | 0:52:53 | |
to start that process. | 0:52:53 | 0:52:57 | |
You can see some of the components have come apart. | 0:52:57 | 0:53:00 | |
What sort of stuff is down here? | 0:53:00 | 0:53:02 | |
We have a significant amount of spent nuclear fuel. | 0:53:02 | 0:53:05 | |
There are quite a lot of reactor components and isotope cartridges. | 0:53:05 | 0:53:10 | |
Do you want to try and lift that one up, Helen? | 0:53:10 | 0:53:13 | |
-No pressure! -No pressure. | 0:53:13 | 0:53:15 | |
How long has that component been in the pond? | 0:53:15 | 0:53:19 | |
Erm, that's the first time it's been touched in probably 51 years. | 0:53:19 | 0:53:23 | |
It seems a whole range of different things are there - | 0:53:23 | 0:53:26 | |
why were they all put in the pond together like this? | 0:53:26 | 0:53:29 | |
The pond was there supporting the effort towards getting us a bomb together. | 0:53:29 | 0:53:33 | |
It was rushed, | 0:53:33 | 0:53:35 | |
We had to get that bomb ready for the early '50s | 0:53:35 | 0:53:38 | |
to prove that we had it, and, once we had the bomb, | 0:53:38 | 0:53:41 | |
I guess things got forgotten about. | 0:53:41 | 0:53:44 | |
Right. Well, now that you've sort of made me somewhat nervous, | 0:53:44 | 0:53:48 | |
I still would like to have a go. | 0:53:48 | 0:53:51 | |
Give it to me when you know I can't do any harm! | 0:53:51 | 0:53:54 | |
-So can I look inside what's in here? -Yeah. | 0:53:54 | 0:53:57 | |
This one has got isotope cans that have corroded. | 0:53:57 | 0:54:01 | |
-So all of that is... -It's started to bow and overflow. | 0:54:01 | 0:54:04 | |
It's like... | 0:54:04 | 0:54:06 | |
the nastiest kind of buried treasure you could imagine! | 0:54:06 | 0:54:09 | |
How dangerous is this stuff? | 0:54:11 | 0:54:13 | |
In situ, as it stands with a five-metre water covering, | 0:54:13 | 0:54:16 | |
it's less dangerous than you would imagine. | 0:54:16 | 0:54:18 | |
The dose rates coming off it are minimal. | 0:54:18 | 0:54:21 | |
However, if some of the material were allowed to dry out, | 0:54:21 | 0:54:25 | |
that would be a different matter - | 0:54:25 | 0:54:26 | |
it could cause a major contamination hazard. | 0:54:26 | 0:54:29 | |
The fact that this stuff is down there and is so nasty - | 0:54:29 | 0:54:32 | |
for many people, this is an argument against nuclear power, | 0:54:32 | 0:54:35 | |
"Look, this is the sort of mess that it creates." | 0:54:35 | 0:54:37 | |
This is certainly an argument against the way things were dealt with 50, 60 years ago, | 0:54:37 | 0:54:42 | |
but we have a duty to clean it up. | 0:54:42 | 0:54:44 | |
We can't just leave the hazard for yet another generation. | 0:54:44 | 0:54:47 | |
And yet, in some way, I can't help feeling we are still leaving it | 0:54:54 | 0:54:58 | |
for another generation, just in safer stores. | 0:54:58 | 0:55:02 | |
The waste from the ponds will be stored in steel containers. | 0:55:04 | 0:55:07 | |
The dead reactors are just stored in concrete blocks. | 0:55:09 | 0:55:13 | |
And the most radioactive material of all, | 0:55:15 | 0:55:17 | |
the vitrified high-level waste, | 0:55:17 | 0:55:20 | |
is still in a warehouse on site here at Sellafield. | 0:55:20 | 0:55:23 | |
I think we do need long-term options for this waste. | 0:55:26 | 0:55:29 | |
Can we store it safely in places like this for 100 generations? | 0:55:29 | 0:55:33 | |
The current long-term plan is to bury it deep underground, | 0:55:34 | 0:55:39 | |
locking it away for ever... | 0:55:39 | 0:55:40 | |
..but this plan continues to divide opinion. | 0:55:42 | 0:55:45 | |
Personally, I believe that if we do bury it, | 0:55:49 | 0:55:51 | |
we have to have the option of being able to retrieve it | 0:55:51 | 0:55:54 | |
at some point in the future | 0:55:54 | 0:55:55 | |
because if we're to have a nuclear industry - | 0:55:55 | 0:55:58 | |
and I think we should - | 0:55:58 | 0:56:00 | |
we need to deal with this waste permanently. | 0:56:00 | 0:56:03 | |
And one possible option that fascinates me | 0:56:03 | 0:56:06 | |
is to find a way to transmute it - | 0:56:06 | 0:56:08 | |
bombard it with a high energy, high intensity beam of neutrons | 0:56:08 | 0:56:12 | |
that smashes it up into far less harmful fragments. | 0:56:12 | 0:56:16 | |
I think this is an option worth exploring | 0:56:16 | 0:56:19 | |
because I believe nuclear power, alongside renewables, | 0:56:19 | 0:56:22 | |
is crucial for our future energy needs. | 0:56:22 | 0:56:25 | |
The story of Sellafield is the story of the British nuclear age. | 0:56:34 | 0:56:38 | |
Sellafield began as a headlong rush to develop nuclear weapons and nuclear power | 0:56:43 | 0:56:49 | |
with little thought to the future. | 0:56:49 | 0:56:51 | |
It appeared to be a success... | 0:56:53 | 0:56:55 | |
..then the cracks started to show - | 0:56:57 | 0:57:00 | |
leaks and the fire released deadly radioactivity | 0:57:00 | 0:57:03 | |
out into the air and sea. | 0:57:03 | 0:57:05 | |
And successive governments and, indeed, the public themselves | 0:57:07 | 0:57:10 | |
demanded that the nuclear industry clean up its act. | 0:57:10 | 0:57:14 | |
With massive investment, | 0:57:18 | 0:57:19 | |
Sellafield seemed to enter a more responsible phase | 0:57:19 | 0:57:22 | |
in managing nuclear waste. | 0:57:22 | 0:57:24 | |
And, as we deal with the issues of climate change, | 0:57:24 | 0:57:27 | |
it seems we might be on the cusp of a new nuclear age. | 0:57:27 | 0:57:31 | |
Where I'm walking now is a proposed site | 0:57:35 | 0:57:38 | |
for the next generation of nuclear power stations, | 0:57:38 | 0:57:41 | |
just a few hundred metres from Sellafield - | 0:57:41 | 0:57:43 | |
so in the shadow of the very first. | 0:57:43 | 0:57:46 | |
This seems a poignant place | 0:57:47 | 0:57:49 | |
to ponder the lessons we can take from Sellafield. | 0:57:49 | 0:57:52 | |
We've understood, slowly and not without mistakes, | 0:57:52 | 0:57:56 | |
that if we are to have a nuclear industry, | 0:57:56 | 0:57:58 | |
then we have to think in the long term - | 0:57:58 | 0:58:01 | |
not just for the quick buck or because of political pressure, | 0:58:01 | 0:58:05 | |
but in terms of the many decades, even centuries, | 0:58:05 | 0:58:08 | |
it takes from conception all the way through to the end of clean-up. | 0:58:08 | 0:58:13 | |
And this is an important lesson, not just for the nuclear industry, | 0:58:13 | 0:58:16 | |
but for any of mankind's more ambitious projects - | 0:58:16 | 0:58:19 | |
be they scientific, engineering, political - | 0:58:19 | 0:58:22 | |
we must take the long view. | 0:58:22 | 0:58:25 | |
Otherwise, well, we have learnt nothing. | 0:58:25 | 0:58:28 |