**Nuclear containment risk — Fairewinds Energy Education

Fairewinds: ” During the 1960s when the American Advisory Committee on Reactor Safeguards debated containment structures, some members argued for the need to make stronger containments. Regrettably, a majority of the members believed that the emergency core cooling systems were adequate, so more than 50 years ago the Advisory Committee ignored its minority members and pushed ahead without rigorous failure-proof containment structures and systems. The Nuclear Regulatory Committee made the decision not to require stronger containments. Japan followed the American lead.

In our most recent video, Fairewinds’ chief nuclear engineer Arnie Gundersen introduces us to the containment structures deemed adequate and strong enough by the NRC to protect civilians from nuclear meltdown. How could five radiation barriers fail at Fukushima Daiichi? Using the childhood game of dominoes, each domino represents a failed radiation barrier and like the game when a domino falls all others follow. Nuclear containment risk is nuclear power’s fifth domino. Nuclear site failures are not a game and public safety is not something to play with- so why does the NRC act like a group of kids putting us all at RISK? ”

Video source with the typed transcript and a relevant video by NHK World.

Fishers submit request over Tepco wastewater plan – NHK World

” Japanese fishers have demanded that the operator of the crippled Fukushima Daiichi nuclear plant gain their understanding before releasing decontaminated water into the sea. ”


Read related articles by The Asahi Shimbun and The Japan Times posted on Sept. 21, 2014.

Plant-based molecule may be key to cleanup of Fukushima nuclear reactor disaster — Phys.org

” A Virginia Tech professor is part of a team of scientists from Japan and the United States that may have discovered a way to remove radioactive cesium from the millions of gallons of contaminated water being held at Japan’s Fukushima Daiichi Nuclear Power Plant following the 2011 disaster.

“Radioactive cesium is the major radioactive component from the reactor,” said Barry Goodell, professor of sustainable biomaterials in Virginia Tech’s College of Natural Resources and Environment. “Researchers in Japan have been seeking better ways to selectively separate out and collect the cesium from the wastewater and from seawater where the radioactive material has leaked, but it has been a difficult challenge.”

The team’s discovery stemmed from their work with lignin, a component of plant cell walls that is a hugely abundant byproduct of pulp and paper production.

Yuichiro Otsuka, a researcher at the Forestry and Forest Products Research Institute in Tsukuba, Japan, and Tomonori Sonoki, professor of biochemistry and molecular biology at Hirosaki University in Japan, have been working with Goodell on ways to use waste lignin to produce more useful “platform chemicals” that can be used as precursors for the production of biofuels and biopolymers (bioplastics).

Through a bacterial fermentation of lignin waste compounds, the team was able to produce a unique molecule known as PDC, which can be combined with other molecules, or polymerized, into a variety of useful bioplastic compounds. The team determined the process for making large amounts of PDC from several types of lignin from pulp mills.

Although the targeted PDC molecule was intended as a platform chemical for biopolymer production, a surprising finding by Otsuka while working in Goodell’s lab led to a discovery that may help clean up radioactive cesium.

“Cesium is a unique compound known as an alkali metal,” explained Goodell, who is also a faculty member in Virginia Tech’s Macromolecules and Interfaces Institute. “Metals like this can be removed from solutions if appropriate binding compounds can be identified, but finding an appropriate compound for the binding of cesium has been very difficult. The Japanese have been desperate to find an alkali metal binding compound that is specific to cesium.”

Because of the chemical structure of PDC, Otsuka surmised that it might also be able to bind certain alkali metals. In the lab, when the PDC compound was tested on a nonradioactive isotope of cesium, the scientists discovered that PDC is especially good at both binding to cesium and pulling it out of a solution in a manner so that it could be readily collected.

“When tests of the PDC were done with mixtures of other metal salts such as sodium chloride, the common table salt that is also the major salt in seawater, cesium was selectively bound by the PDC, allowing it to be pulled out of the solution for selective disposal,” Otsuka explained.

“This could be a finding of major importance for the cleanup of the Fukushima Daiichi reactor disaster,” he added.

Japanese researchers, including Masaya Nakamura, head of the Microbial Bioprocessing Section of the Forestry and Forest Products Research Institute, who previously did a sabbatical in Goodell’s lab, are now exploring how the PDC compound can be further scaled up and how it can be applied to wastewater in Japan contaminated with radioactive cesium. ”


Fukushima operator to miss deadline on decontaminating water — Reuters

” (Reuters) – The operator of the wrecked Fukushima nuclear plant, Tokyo Electric Power Co, said it would not be able to meet a self-imposed deadline to decontaminate water containing highly radioactive substances by the end of March.

The admission by the utility known as Tepco is another setback in its struggle to cope with the contaminated water, which is mostly contained in hastily constructed tanks.

Tepco President Naomi Hirose visited officials at the Nuclear Regulation Authority on Friday to report that the company would not be able to process all the contaminated water by the end of March as promised.

“I feel very sorry that I was not able to carry out my promise to process (the contaminated water),” Hirose said.

“At our current pace we will complete it by mid May,” he added.

Tepco has been fighting a daily battle against contaminated water since Fukushima was wrecked by an earthquake and tsunami in March 2011 and three reactors underwent meltdowns.

Water flushed over the wrecked reactors to keep them cool enough to prevent further radioactive releases is leaking into basements after contact with the melted uranium fuel.

The water mixes with groundwater that seeps into the basements, requiring more pumping, treatment and storage.

Missteps and leaks have dogged the efforts to contain the water, slowing down the overall decommissioning process, which is expected to take decades. ”


Updated 1/30/15, NHK World; Tepco to rely on cosmic beams to glimpse melted fuel inside Fukushima reactors — The Asahi Shimbun

Updated Jan. 30, 2015, NHK World:

Watch this video that explains how operators plan to use muon tomography imaging to figure out where the melted fuel at Fukushima Daiichi is, starting with Unit 1.

* * *

Posted Jan. 25, 2015, The Asahi Shimbun: ” Tokyo Electric Power Co. will use cosmic rays at the crippled reactors at its Fukushima plant to identify sites with melted fuel.

TEPCO will install special equipment to observe muon beams, or particles generated when cosmic radial rays collide with the atmosphere. That will enable it to glimpse inside the reactors, which went into triple meltdown after the March 2011 earthquake and tsunami disaster.

The exercise is intended to generate data that will be useful in deciding how to eventually remove the fuel. Fuel extraction work will be the most difficult phase in decommissioning the beleaguered plant.

While the muons pass through concrete, iron and other construction materials, they become absorbed more easily in high-density materials such as uranium, thereby creating a “shadow.” Based on these shadows, TEPCO expects to be able to identify the location and shape of nuclear fuel.

The industry ministry-backed plan will be led by the International Research Institute for Nuclear Decommissioning, an organization comprising TEPCO and atomic facility manufacturers.

They will first study the No. 1 reactor building and compile results by the end of this fiscal year, estimating how much fuel remains in the reactor.

While some experts argue that almost all of the fuel has melted and dropped to the base of the containment vessel at the No. 1 reactor, others say half of it probably remains in the reactor core.

TEPCO and the central government intend to extract the melted fuel after surrounding it with water to block radiation. To do so, the plant operator will need to repair damaged sections of the containers to prevent water leaks.

An industry ministry official said the survey “will provide important data for deciding how much water to inject into the containers.”

However, as there are also limitations to the method, the study represents just the first step in ascertaining what is happening inside the stricken reactors.

For instance, nuclear fuel at the base of the container cannot be seen using the muon technique, because the particles are not coming from below the reactors. As the system’s resolution is 30 centimeters to 50 cm, small compounds of fuel will also be undetectable.

“Many unknown factors remain, such as what sort of obstacles are at play in the reactor buildings,” said Fumihiko Takasaki, professor emeritus at the High Energy Accelerator Research Organization, which was involved in the development of the observation equipment. “We cannot know whether the efforts will eventually prove successful unless we actually try.” ”


Robot to work at Fukushima disaster scene — Übergizmo

” Robots are wonderful workers for a few reasons – they do not get tired, [and neither do they] complain [nor] will they congregate around a water cooler to gossip about their superior and his or her flaws. Not only that, robots do not have union[s] and [are] unable to go on strike – not to mention in a more practical manner, enter places which are deemed dangerous for the average man on the street – such as at a nuclear disaster site as we have seen in the past. This time around, a UK start-up has developed a robot that will help to locate hazardous radiation sources at the scene of the Fukushima disaster in Japan.

Createc is the company behind the camera technology known as N-Visage which will see [robots in action] suited up for such a task, where [they] detect and draw a 3D map of high radiation locations which are deemed to be too contaminated for human workers to actually be in.

This is a big step for UK companies where the realm of robotics are concerned, as British ministers intend to see the UK play catch up with other countries such as the US, Japan and South Korea. The N-Visage camera technology that is implemented in stair-climbing robots will allow those robots to arrive at inaccessible areas that are located deep inside the nuclear site. ”