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I worked at Hamaoka nuclear plant for a little over 5 years, but it was not the only time I’d worked at a power plant. Before Hamaoka, I spent my 30s working at a nearby nuclear plant for about 10 years in the 1980’s. At that time, I did not work at just one site but was moving from one plant to another to do regular maintenance work. Recently, that kind of people are called “Nuclear gypsies” with a bit of contempt and in that period I was living as one of those. Two years after I began the wandering life of a gypsy, I entered for the first time the core container of a steam generator. At the time I was working at the Genkai Nuclear Power Plant in Saga Prefecture. [Editor's note: In brief, there is a containment building within the plant. This houses the core and the steam generator.] The core is the part of the reactor where uranium fuel undergoes nuclear fission. It generates heat which is then passed to The steam generator which produces the steam to power the turbines which turn the generators elsewhere in the plant . The level of radioactivity in the containment building is very high compared to elsewhere [in the plant]. My job involved entering [the generator] and installing a robot monitor that would enable examination of whether there was any damage in the steam generator.

Actually what happened on the day was that another person replaced me and entered the steam generator to install the robot. After the installation was completed, there was a problem in that the robot wouldn’t respond and thus could not be operated from outside. There are many small holes in the walls of the central part of the steam generator and the six (I believe there were six) ‘legs’ of a robot, operated via a remote control, should be able to survey it through those holes. The employees in charge of supervising the installation concluded that there had been a problem in properly positioning the robot’s legs.

If the ‘legs’ are not completely inserted and the robot is left in that position, it could fall down at any time. If that happens, it spells the loss of a precision machine that's said to be worth several hundred million yen. That’s why I was sent in to enter the generator, on very short notice, to replace the robot back to its correct operating position before that happened. I started putting on the gear to enter the housing at a spot near the steam generator. Two workers helped me put it on. I was already wearing two layers of work clothes, and on top of those, I put on Tyvek protective gear made of paper and vinyl, and an airline respirator. Plus, I wrapped a lot of vinyl tape around my neck, my wrists and my ankles, to block even the slightest opening.

Once I finished putting on the protective gear — which honestly looks like an astronaut suit — I headed toward the housing. When I arrived at the area near the housing, two workers were waiting. They were employees of a company called the Japanese Society for Non-Destructive Inspection [JSNDI] and, to my surprise, despite the area being highly radioactive, they were wearing nothing but plain working clothes. They weren’t even wearing masks. The person who appeared to be in charge invited me over and, after a look at my eyes inside the mask, nodded his head a few times. I guess just looking into my eyes he was able to determine that I’d be able to handle working in the core.

He and I went to the steam generator together.

The base of the steam generator more or less reached my shoulder, at slightly less than 1.5m. At the bottom, there was a manhole. The manhole was open, and I immediately realized I would have to climb up into it.

The JSNDI employee in charge put his arm around me and together we approached the manhole. We looked over the edge and peered in. Inside was dark, and the air was dense and stagnant. It felt as though something sinister was living inside. My expression glazed over. A slight sensation of dread came over me. As I approached the manhole, I noticed a ringing in my ears and felt reluctant to go in. When I looked inside, I saw that the robot was attached to the wall indicated by the [JSNDI] employee. It was not properly attached, which is why I had been sent in.

The robot was square-shaped, 40 cm on each side and 20 cm deep. It was called a ‘spider robot’. The JSNDI employee put his face at the edge of the manhole, a third of his face peering in, and diligently explained what I had to do. There was little awareness at the time of the dangers to workers of radiation exposure, but even so I was concerned about the bold act of the employee, who looked inside the housing with me. He continued looking inside, unfazed, and I remember wondering why he wasn’t scared. I was almost completely covered while he wasn’t even wearing a mask. […]

I stood up, climbed the ladder, and pushed my upper body through the manhole. In that second, something grabbed at my head and squeezed hard. A pounding in my ear started right away.

One worker said that right after he entered a nuclear reactor he heard a noise like a moving crab. “zawa,zawa,zawa…” He said that he could still hear this noise after he finished the work. Even after the inspection work, when he went back home, he couldn’t forget that noise. The man ended up having a nervous breakdown. A writer who heard this story spoke to this man and wrote a mystery novel based on that experience. The title of the book is “The crab of the nuclear reactor”. It was published in 1981 and was very popular among us.

I never heard such a crab-like noise but I had the feeling that my head was being tightly constricted and deep in my ears I heard very high-tempo echoes like a sutra “gan, gan, gan”. When I entered the steam generator I stood up all of a sudden and my helmet hit the ceiling. So I had to bend my neck and hold both the arms of the robot in the darkish room. “OK” I screamed. So the robot was unlocked and its feet jumped out of the hole. The entire robot was not as heavy as I had thought. After I matched its feet position in the holes I gave them another OK sign and so it was positioned in the hole. In the dark, when I verified that all the feet had entered into the holes I gave them another OK and jumped out of the manhole. […]

Once outside,] I was almost in shock but looked at the alarm meter and saw that it had recorded a value equal to 180, when the maximum it can record is 200. In only 15 seconds, I was exposed to an unbelievably high level of radiation, 180 millirem. At that time the unit ‘millirem' was used while now it’s different. Now everybody uses sievert. That time I was in charge of an inspection work that lasted about 1 month. After that I worked in another nuclear reactor but even on the second time I couldn’t get through the fear and experienced the same creepy noise.

According to Kyodo News Japanese, the room is called the "train room" by TEPCO.

"Cleaning," "waiting," and "dismantling" are the three key actions in this process. Needless to say, this all needs to be done while simultaneously containing radioactive materials.

In the case of the Tokai Nuclear Power Plant, the first commercial plant to undergo decommissioning, spent fuel was removed over a span of three years beginning in 1998, and was transported to Britain for reprocessing. Dismantling of the facilities began in 2001, with current efforts being made toward the dismantling of heat exchangers; workers have not yet begun to take the reactor itself apart. The entire process is expected to be an 88.5-billion-yen project involving 563,000 people.

Hitachi Ltd., which manufactures nuclear reactors, says that it "generally takes about 30 years" to decommission a reactor. The Hamaoka Nuclear Power Plant's No. 1 and No. 2 reactors operated by Chubu Electric Power Co. are also expected to take about 30 years before they are decommissioned.

In the case of the Fukushima No. 1 Nuclear Power Plant, meanwhile, the biggest challenge lies in how to remove the fuel, says Tadashi Inoue, a research advisor at the Central Research Institute of Electric Power Industry (CRIEPI), a foundation that conducts research on energy and environmental issues in relation to the electrical power industry.

"we must deal with rubble contaminated with radioactive materials that were scattered in the hydrogen blasts and treat the radiation-tainted water being used to cool nuclear fuel before we can go on to fuel removal."

Currently, the Fukushima plant's operator, Tokyo Electric Power Co. (TEPCO), is desperately trying to treat the contaminated water. Huge challenges remain with regards to the contaminated rubble, as radiation levels of over 10 sieverts per hour were found near outdoor pipes on the plant grounds just the other day. Exposure to such high levels would mean death for most people.

Each step in the process toward decommissioning is complicated and requires great numbers of people. It's a race against time because the maximum amount of radiation that workers can be exposed to is 250 millisieverts.

The breached reactor core is a bigger problem. It is believed that raising water levels inside the reactor has been difficult because of a hole in the bottom of the vessel. It will be necessary to plug the hole, and continue filling the vessel with water while extracting the melted fuel. How to fill the vessel with water is still being debated. If the reactor can be filled with water, steps taken after the 1979 Three Mile Island nuclear accident can serve as a guide because in that case, in which approximately 50 percent of the core had melted, workers were able to fill the reactor with water and remove the fuel within.

Two types of fuel removal must take place. One is to take out the spent fuel in the containment pools, and the other is to remove the melted fuel from the reactor cores. Because the radiation levels of the water in the spent fuel pools have not shown any significant changes from before the crisis, it is believed that the spent fuel has not suffered much damage. However, removing it will require repairing and reinstalling cranes to hoist the fuel rods out.

Prefacing the following as "a personal opinion," Inoue says: "Building a car that can protect the people inside as much as possible from radioactive materials, and attaching an industrial robotic arm to the car that can be manipulated by those people could be one way to go about it."

Inoue predicts that removal of spent fuel from the containment pools will begin about five years after the crisis, and about 10 years in the case of melted fuel from the reactor core. Work on the four reactors at the Fukushima plant will probably take several years.

"Unless we look at the actual reactors and take and analyze fuel samples, we can't know for sure," Inoue adds. Plus, even if workers succeed in removing the fuel, reprocessing it is an even more difficult task. A review of processing methods and storage sites, moreover, has yet to take place.

Meanwhile, at least one expert says he doesn't believe that workers will be able to remove the melted fuel from the crippled plant.

"If there's 10 sieverts per hour of radiation outside, then the levels must be much higher closer to the reactor core," says Tadahiro Katsuta, an associate professor at Meiji University and an expert in reactor engineering and reactor policy who was once a member of an anti-nuclear non-profit organization called Citizens' Nuclear Information Center (CNIC). "The fuel has melted, and we haven't been able to cool it consistently. If work is begun five or 10 years from now when radiation levels have not yet sufficiently gone down, workers' health could be at serious risk."

Katsuta predicts that it will probably take at least 10 years just to determine whether it is possible to remove the fuel. He adds that it could very well take 50 years before the task of dismantling the reactor and other facilities is completed.

What Katsuta has in mind is a Chernobyl-style concrete sarcophagus, which would entail cloaking the melted tomb with massive amounts of concrete. "How could we simultaneously dismantle four reactors that have been contaminated to the extent that they have by radioactive materials?" asks Katsuta. "Japan has little experience in decommissioning reactors, and this case is quite different from standard decommissioning processes. It's not realistic to think we can revert the site back to a vacant lot. I think we should be considering options such as entombing the site with concrete or setting up a protective dome over the damaged reactor buildings

what we face is a great unknown to all of mankind.

In a week’s time, the company plans to transfer the contaminated water from reactor 2 to a nuclear waste facility that can store some 30,000 tons of such water.

In short,we must pay 6 times more price for Fukushima. Yes,nuclear is cheap,and environmentally friendly.