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00:12A robot makes its way through a narrow pipe.
00:23It was created to help with the inspection of the Fukushima Daiichi nuclear power plant.
00:31It's equipped with a small camera to capture the nuclear fuel left inside reactors where meltdowns occurred.
00:46Japan has set out to decommission the Fukushima plant.
00:49It's expected to take up to 40 years.
00:55Strong radiation presents a serious obstacle to be overcome before anyone can go near the reactors.
01:11Three reactors melted down in the accident at Fukushima.
01:15No one has ever decommissioned three reactors at one time before.
01:24It might take 30, 40 years or more.
01:28We must all work together to stabilize the plant.
01:33What challenges are in store for Japan?
01:37Past nuclear plant accidents shed light on the difficulty involved.
01:42In 1979, a serious nuclear accident occurred at Three Mile Island in the United States.
01:53NHK has obtained about a thousand videotapes that document the entire process of decommissioning the plant.
02:04The footage offers a clear account of ten arduous years spent cleaning up the debris.
02:12We're approaching five feet.
02:15We're now five...
02:15Got something.
02:17Boy, a lot of debris.
02:21Jesus.
02:25Good to see you, sir.
02:28Officials from the government and Tokyo Electric Power Company are trying to learn from these experiences abroad.
02:36The challenge is huge.
02:38It makes Three Mile Island look very simple.
02:40What you have is much more complex, much more challenging.
02:49The effort to dismantle the damaged reactors will take generations.
02:53The cost will be staggering.
03:02What difficulties await the people involved?
03:05To find out, NHK will take its cameras inside Fukushima for the next 40 years.
03:18We'll document the entire process in our series, Decommissioning Fukushima.
03:33The Fukushima accident was one of the worst nuclear disasters the world had ever seen.
03:39Three reactors melted down, one after another.
03:48Experts believe the fuel melted through the bottom of the reactors and reached the containment vessels.
03:55The melted fuel turned into fuel debris.
04:01There's an estimated 270 tons of it in the three damaged units.
04:07Removing it and dismantling the reactors are at the heart of the decommissioning process.
04:20TEPCO and the Japanese government drew up this schedule.
04:26It spells out the task that must be completed over four decades.
04:34The site must be decontaminated.
04:41The containment vessels must be inspected to determine the state of the debris.
04:47It's a long, complex process.
04:56The process includes three key phases.
04:59First, preparations must be made to remove the fuel debris.
05:02Then comes the actual removal, followed by disposal and dismantlement.
05:09The greatest challenge will be removing the fuel debris.
05:12That won't start until at least 2020.
05:20Workers will use a crane to remove the debris and cameras to monitor their progress.
05:25If all goes well, the removal phase will be completed in about 20 years.
05:38The 40 year long decommissioning process will be financed through taxes and electricity fees.
05:45It's expected to cost more than 20 billion dollars.
05:54In April 2014, Tokyo Electric Power Company, or TEPCO, established a special entity to manage the decommissioning process.
06:04The group is headed by Naohiro Masuda.
06:11Masuda will oversee some 800 domestic manufacturers and large construction companies.
06:19We need to assemble all kinds of expertise.
06:22First, we need to draw a clear picture of what we must do to decommission our Fukushima Daiichi plant,
06:28then figure out how to get there.
06:31Our goal is to create a safe environment.
06:33We'll proceed accordingly.
06:54It will be a long, drawn out battle.
07:03In the three years since the accident, workers focused on reducing radiation by removing contaminated debris.
07:14The radiation must have made it difficult at first.
07:18Well, everyone worked hard to bring it down to current levels.
07:28Immediately after the accident, radiation levels were so high that people could only work on the grounds for a short
07:34time.
07:36But now, levels are much lower.
07:46Finally, decontamination of the area around the containment vessels is about to start.
07:53Surveys are underway to find out just how contaminated it is.
08:04Now, only robots can operate inside the buildings that house the reactors.
08:13The survey is being spearheaded by this robot, called Meister.
08:17Meister.
08:20Meister can measure radiation levels and collect contaminated objects.
08:31Robots can go where humans can't and perform tasks almost as well as people.
08:40I'll be happy if they can be of use here.
08:47In March 2014, a container with Meister inside was lifted into the facility with a giant crane.
09:04It was placed on the top floor of Unit 2, known as the operating floor.
09:12No explosions occurred in Unit 2, so officials believe debris removal can begin relatively quickly there.
09:19The operating floor will become an important base of activity.
09:26The container arrived at the entrance.
09:30And the contamination survey began.
09:54Relying on images from Meister's onboard camera, engineers use remote control to guide the robot to the operating floor.
10:04The immediate goal was to take samples of concrete from three locations on the operating floor to get a detailed
10:11picture of contamination levels.
10:15But fences blocked the robot's path.
10:25So another robot, called Warrior, went ahead to clear the way.
10:42Warrior managed to remove portions of the fence.
10:50But the earthquake and other disruptions had scattered an unexpected amount of debris across the operating floor.
10:58Meister had trouble getting through.
11:16Meister inched forward, weaving through the debris.
11:26Meister inched forward, weaving through the debris.
11:30When trouble had been in place.
11:35A little way ahead, Warrior had tipped over on the uneven floor and could no longer function.
11:45The team had to abandon sampling at two of the three planned locations.
11:52Meister headed for the remaining spot.
12:03It then began cutting out a sample from the floor.
12:12The team wanted to know how much radioactive material the floor had absorbed.
12:37Meister managed to get a sample of the concrete.
12:46The sample was then analyzed for contamination.
13:10Special equipment was used to examine the concrete.
13:20This image shows the sample from the top.
13:26This black area means very high radioactivity.
13:32Further analysis showed that the concrete had absorbed radioactive material to a depth about
13:37one millimeter.
13:42This radiation can't be removed simply by washing the surface.
13:52We need to scrub the surface or remove the contaminants.
13:58It's not going to be easy.
14:07This was the status of contamination in Unit 2 at the time.
14:16One area on the first floor registered 4,400 millisieverts.
14:23Enough to kill a person in two hours.
14:32On the operating floor, a maximum level of 880 millisieverts was recorded.
14:40Apparently, the entire facility was heavily contaminated.
14:54One crucial step must be taken before the fuel debris can be removed.
15:02The melted fuel inside the containment vessels needs to be examined.
15:16How can the team find out the actual state of the fuel debris?
15:27Possible approaches are being studied for Unit 1, where the team thinks the largest amount of debris is located.
15:36One promising access route is a duct leading into the containment vessel.
15:41It was once used for routine inspections.
15:47It's our only way into that harsh environment.
15:52We just don't know what things are like inside.
15:57This is our only access point.
16:07The duct is called X6.
16:12It has a diameter of 55 centimeters.
16:17It's big enough to allow many different kinds of robots to pass through.
16:25But can workers get close enough to X6 to set up the robots?
16:38In December 2013, a radiation survey was conducted in Unit 1.
16:48A robot equipped with the latest gamma ray camera was sent into the area around X6.
16:58The color indicates the intensity of the radiation.
17:10The robot passed through some very strong radiation.
17:15But at one particular spot, the radiation level shot up.
17:23Conditions changed dramatically at a point several meters from X6.
17:47The red color was centered on a vent pipe that ran along the ceiling.
17:53Detailed analysis revealed a radiation level of 1,600 millisieverts per hour.
18:06This pipe greatly increased the radioactivity level of the entire area.
18:11The pipe won't be easy to decontaminate, so workers can't get too close.
18:24The team turned its attention to an area on the opposite side where radiation levels were relatively low.
18:34Another duct was located there.
18:39But it was only 10 centimeters in diameter.
18:49Work is now underway to develop a robot that can pass through this narrow duct.
19:03Satoshi Okada is in charge of development.
19:09His team is creating a snake-like robot that can pass through the narrow duct.
19:20Once it gets through, it will change shape inside the containment vessel.
19:30While rolling over obstacles, it will film the debris using a small onboard camera.
19:47We want to see inside the vessel as quickly as possible.
19:51Then we'll conduct tests on the fuel debris inside.
19:55We're hoping to get started on that soon.
20:02The team plans to insert the new robot into the containment vessel by March 2015.
20:13We have extremely high radiation levels in units 1, 2 and 3.
20:20Right now, access is very difficult.
20:23We must work in places where people can't enter.
20:27Deciding what to do is the biggest challenge.
20:33Preparations to remove fuel debris have just begun at the Fukushima Daiichi nuclear plant.
20:41What challenges lie ahead?
20:53The government and TEPCO are trying to learn from experience abroad to gain a better understanding of what awaits them.
21:11Lake Barrett is the utility's international advisor.
21:14He was involved in decommissioning the Three Mile Island nuclear plant when he was with the US Nuclear Regulatory Commission.
21:27The challenge is huge. It makes Three Mile Island look very simple.
21:31What you have is much more complex, much more challenging.
21:36It's a strong team. And you can do it. I'm very confident you can.
21:43But there are a lot of challenges you have to meet.
21:50The Three Mile Island nuclear accident took place in 1979.
22:07But only one Three Mile Island reactor melted down.
22:11Compared to Fukushima, relatively little radioactive material escaped.
22:15And there was no long-term displacement of nearby residents.
22:20Even so, the decommissioning process proved to be very difficult.
22:31The entire process was recorded on about a thousand videotapes.
22:36NHK received special permission from the US government to view them.
22:44Before Three Mile Island, no one had ever tried to remove fuel debris.
22:48The tapes show that the process didn't proceed as smoothly as planned.
22:59Three years after the accident, radiation levels were finally low enough to allow workers to enter the plant.
23:10This was the first footage taken inside the reactor.
23:17Today is July 21.
23:20The TMI-2 inspection team is now on top of the TMI-2 reactor vessel.
23:25And about to attempt to make the first inspection into the TMI-2 reactor vessel proper.
23:34Workers inserted the camera from the top and lowered it into the reactor to take a closer look at the
23:40nuclear fuel.
23:47During the Three Mile Island accident, the cooling water level went down, exposing the fuel.
23:55But unlike the case at Fukushima, engineers at Three Mile Island were able to quickly fill the reactor with cooling
24:02water.
24:02So many believed the fuel had sustained little, if any, damage.
24:14However, we're now at the, at where the water should be.
24:19Going on down.
24:21Going on down.
24:23The water is very milky.
24:27We're one foot into the core.
24:30We have had a hard, Bill just hang on, hold it right there.
24:33Trying to see something.
24:34Yeah.
24:36People thought we would see the fuel.
24:38Well, you know, it went one foot, two foot, three foot, four foot, and we didn't see the fuel.
24:48Why couldn't the workers find the nuclear fuel?
24:51We're now approaching three feet.
24:55We're, we are approaching four feet.
25:01We're approaching five feet.
25:04We're now five.
25:05That's something.
25:06We are now five feet into the core.
25:10Boy, a lot of debris.
25:13Jesus.
25:19They found objects that looked like rocks.
25:22They were the remains of fuel that melted so much that it lost its original shape.
25:30Something unexpected had happened.
25:41Nearly half the nuclear fuel had melted and fallen in the meltdown.
25:46There was more than 100 tons of fuel debris.
25:53Okay.
25:54So, I mean, it was just like silence in the room.
25:56It was a turning point once you knew what it was.
25:59And all the engineers then could stop speculating on assumptions and could then focus on what
26:05it was.
26:10The engineers constructed a work platform above the reactor to get the debris out.
26:17They lowered long cutting tools up to 12 meters inside the reactor and removed the hardened debris
26:23a little bit at a time.
26:30Fuel removal didn't begin until six years after the accident.
26:40The tapes recorded the difficulty of working underwater.
26:52There.
26:52You got it.
26:53It's under it now.
26:54I think it's loose.
26:56Oh, that'll come right out of it.
26:57Workers tried to remove obstacles that prevented them from getting the debris out.
27:02Okay.
27:03Okay.
27:04I'm bringing it up.
27:06Okay.
27:07It's out of the can.
27:08Oh, that fell better.
27:09I fell back in.
27:11Wait a minute.
27:12It's a bug.
27:14It's a bug.
27:14It's a bug.
27:18Another problem was the large number of microorganisms that flourished in the reactor's warm environment.
27:25They obscured the operator's view, making the work go much slower.
27:37William Austin was in charge of debris removal at the time.
27:47At Three Mile Island, all the debris stayed inside the reactor.
27:50But at Fukushima, it melted through the bottom of the reactor to the containment vessel below.
27:59Because of this, workers may have to pull the debris out from a depth of 30 meters.
28:12Holding them 25 foot, supported by a jib crane and a chain fall, and you're trying to put this tool
28:19in position, that's not easy.
28:23So, as you're going down, you're cutting a very deep cut, and you're doing it at depths that are very
28:31difficult to work in.
28:37Another obstacle to removal was the debris's unexpected hardness.
28:47Hitting it repeatedly with a sharp steel pole had virtually no effect.
28:59A heavy hammer couldn't break it up either.
29:02The work had to be put on hold for a time.
29:13Metal had melted in with the fuel.
29:24The team decided to bring in a boring machine used for oil drilling.
29:32Their only choice was to use special drills to cut and remove the debris gradually.
29:46Because of all of these delays, it took five years to get all the material out.
29:58I think we also thought that those tools we had would work, but you saw it was a 300 pound
30:04slide hammer, and it didn't even touch it.
30:09300 pounds just bounced off.
30:11So, it was anticipated, but I don't think we realized how tough it was.
30:22How will Japan make use of the lessons learned at Three Mile Island?
30:26Research is underway.
30:40This specially designed facility can handle radioactive materials.
30:52A sample of debris from the accident at Three Mile Island is stored here.
31:05Even now, it emits high radiation, up to several thousand millisieverts per hour.
31:14Japanese researchers are studying this piece of debris to help with the decommissioning of the Fukushima Daiichi plant.
31:25It's difficult to recreate post-accident conditions, so the debris from Three Mile Island is very important for our analysis.
31:40Researchers at this facility are conducting simulations based on that debris.
31:45They're trying to estimate how hard the debris from Fukushima Daiichi might be.
31:54The experiment suggests that the Fukushima debris might contain more metal than the piece from Three Mile Island, so it
32:02could be even harder.
32:12It's possible that we're dealing with something much harder than the debris from Three Mile Island.
32:19We must figure out what kinds of drills to have ready.
32:23We'll also need to prepare separate tools in case drills aren't enough.
32:29Not everything went smoothly at Three Mile Island.
32:33We want to learn from their mistakes so we can minimize errors at Fukushima Daiichi and proceed with decommissioning as
32:41efficiently as possible.
32:45Experts estimate that the debris from Fukushima will take another 20 years to remove.
32:54They also expect an additional 15 years will be needed to dispose of the debris and finish the dismantling of
33:01the reactors.
33:03And finding a disposal site will be extremely difficult.
33:11But a storage site for the Three Mile Island debris was selected just three years after the accident.
33:21This desolate, expansive Idaho desert is home to a nuclear research facility.
33:27So we're entering the Idaho independent spent fuel storage installation for our Three Mile Island reactor fuel storage.
33:40The 93 tons of Three Mile Island debris is stored here.
34:00Lake Barrett led the project.
34:07He and his team had to overcome many hurdles in their search for a site.
34:17After the accident, nearby residents were deeply suspicious of the government and the utility.
34:38Barrett took a lot of heat.
34:48If that happens, you say, there should not be much more radioactivity released than the amount originally released in the
34:56accident.
34:57How firmly can you give us an assurance of that?
35:02It's very difficult to give a specific answer to that.
35:11Initially, he thought about storing the debris on site.
35:16But criticism from the residents forced him to drop the idea.
35:26Three Mile Island is an island in the middle of the Susquehanna River.
35:29People drink the water.
35:32It's fresh water.
35:33So cities downstream drink it.
35:35It flows into the Chesapeake Bay, where all the crabs and seafood for basically Washington and the city of Baltimore
35:42come from.
35:43So it was a very emotional thing.
35:45So you, they didn't want, the people did not want the fuel, the damaged fuel to remain there.
35:54Where could they send the debris?
35:57The U.S. government suggested the nuclear research facility in Idaho, since it was already storing nuclear fuel.
36:04But Idaho's governor raised an issue.
36:07You had the Idaho governor, okay, was saying, look, you know, we're not, we're not a waste disposal site.
36:14We are R&D.
36:15We do reactor safety research and development.
36:18It's good work.
36:18It's good jobs for the people in Idaho.
36:20And it's valuable information for the whole country.
36:23And the whole world.
36:28Transportation was also a problem.
36:30Moving the debris via freight train over 3,500 kilometers meant traveling through seven states.
36:36And they would have to agree as well.
36:44The government spent millions of dollars to develop a special container to ship the debris.
36:56Experts performed various tests, such as exposing it to open flame and dropping it.
37:01They wanted to make sure radioactive materials wouldn't leak.
37:10Washington sent senior officials to the seven states along the transportation route.
37:15Their mission was to reassure them the shipment was safe.
37:21First of all, I won't concede that, that it could happen.
37:25But if, if it did happen, the, the, the, we in the Department of Energy have the ability to confine
37:31that to a very small area.
37:38The government was finally able to transport the debris to Idaho.
37:42But it's only a temporary solution.
37:45The final destination has not been determined.
37:48It seems no one wants a nuclear disposal site in their backyard.
38:01In Japan, discussions have yet to begin about where to store the debris from the Fukushima Daiichi plant.
38:11What lessons should the nation learn from Chernobyl and Three Mile Island?
38:22What lessons should the nation learn from Chernobyl and Three Mile Island?
38:27That is, in my view, irresponsible.
38:30And I don't believe Japan would ever do that.
38:34We had to do it at Three Mile Island as well.
38:36And you will have to do it here.
38:38But someone needs to start thinking about where is it going to go?
38:43What is the ultimate disposition path?
38:45Who's going to decide that?
38:52Barrett has visited Fukushima.
38:55He said one thing in particular must not be forgotten during the decommissioning process.
39:06Communicating with the local people.
39:12I have a girl.
39:14I'm worried that when she grows up and wants to get married, her fiancé's parents might
39:21not want him to marry someone from this area.
39:27They also questioned whether, because he was working there, if he would bring home radiation
39:35to us.
39:36So I realized it's a difficult position to be in.
39:45This is the central control room for the Fukushima Daiichi nuclear power plant.
39:53Workers continue to monitor radiation levels throughout the site.
40:02They work around the clock.
40:07Many of them were born and raised in Fukushima.
40:17For them, decommissioning is part of the struggle to reclaim their homes.
40:33My family was forced to leave our home town.
40:39I'd like to make it safe for them to return and for my colleagues and acquaintances to
40:46go home too.
40:50Decommissioning will take a long time.
41:04Many garlands of origami cranes hang at the front line of the decommissioning process.
41:15They represent the hopes and prayers of children and displaced people throughout Japan.
41:25For our hometowns, for Fukushima, for Japan, please resolve the nuclear accident as soon as possible.
41:46The road to decommissioning is long indeed.
41:55Can we overcome the many challenges, lighten the burden on future generations?
42:06How society's resolve is being put to the test.
42:10.
42:20ORGAN PLAYS
42:53ORGAN PLAYS
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