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Daily news roundup done www.simplyinfo.org

@RadioGuy Thanks. Trying to blast through some needed content and info this morning before I dive head first into work for the day. I am working on a short article about the cold shutdown BS, the lack of food testing and a tie in to Bo's new article www.dianuke.org

I want to finish up the protect yourself article tonight and hoping to get a plutonium facts one out in a few days so we can push it and hopefully get more information to people so they can try to easily educate those they run into. One of the parents groups members had a teacher tell her plutonium wasn't dangerous unless in huge amounts.

i hope the taifun destroys the dolphin slaughterers' homes.

@Peter Melzer : the reactor temps are far from below boiling temp.

the temps converge to a point above 100°. i wonder how they want to achieve lower temperatures.

@Peter Melzer : maybe for the spent fuel pools, but surely not for the reactors.

@lillymunster : well, they did not say they have a cold shutdown yet. they only use the word "stabilized". cold shutdown is the next step in their roadmap. don't mix it up.

"The taskforce said the first stage of the plan outlined in mid-April for the stable cooling of the reactors has been completed on schedule by mid-July. It added radiation levels in the plant's surrounding areas have been steadily reduced. ..."
"In the second stage of the plan for the cold shutdown of the reactors, TEPCO plans to improve its systems to decontaminate wastewater and to cool reactors and fuel rod pools at the plant."
www3.nhk.or.jp

@Panserbjorne9 : this could be correct, mathematically.

@Peter Melzer

Govt to define "cold shutdown"

The second-stage target to bring the nuclear disaster under control will involve achieving a cold shutdown, under which the disabled reactors are to be cooled down to about 100 degrees Celsius or lower.

The Japanese government is due to make this clear on Tuesday when it releases a revised plan to contain the accident at the Fukushima Daiichi nuclear power plant.

The government has so far failed to specify what a cold shutdown entails. It now plans to define the term as bringing reactor-bottom temperatures to about 100 degrees or lower, and substantially reducing the public's radiation exposure by controlling the release of radioactivity.

Achieving a cold shutdown has been cited as one of the conditions for lifting the 20-kilometer no-entry zone around the Fukushima Daiichi plant.

It remains unclear, however, when the lifting would come, as the government still hasn't decided on benchmark levels of radiation that it deems safe enough for people to return to the restricted zone.

Tuesday, July 19, 2011 09:42 +0900 (JST)
www3.nhk.or.jp

Japan moves on to stage to seek cold shutdown of crippled reactors

TOKYO, July 19, Kyodo

Japan said Tuesday it has succeeded in stably cooling the crippled nuclear reactors at the Fukushima Daiichi power plant and reducing the radiation dose around the site, an announcement that would lead restoration efforts to move on to the next stage of seeking a ''cold shutdown'' of the reactors by January.

In an updated road map to contain the four-month-old nuclear crisis, unveiled the same day, the government said it plans to work out by around autumn safety guidelines to maintain the ravaged plant's stability for a long period, while plant operator Tokyo Electric Power Co. will seek to start removing spent nuclear fuel within three years following the stabilization of the reactors.

''We're starting to see a tremendous critical condition heading toward a certain level of settlement,'' Prime Minister Naoto Kan told a parliamentary committee as he welcomed the completion ''almost as scheduled'' of the so-called ''step one'' phase of the utility's restoration road map.

''Some progress has been made earlier than originally scheduled'' in the step one phase,'' Kan also told a meeting of the government's task force on the world's worst nuclear crisis in 25 years.

The government left unchanged the originally set timeline to achieve the ''step two'' phase, which includes the goal of realizing a cold shutdown of the Nos. 1 to 3 reactors, in the latest scenario.

Industry minister Banri Kaieda said the government could lift a directive that requires residents in a zone 20 to 30 kilometers from the plant to be prepared to evacuate or stay indoors in an emergency, before completing the next phase.

The road map also showed that the government will consider lifting a ban on people entering areas within a 20-kilometer radius of the plant towards the end of the step two phase, which is to be implemented in the three to six months following the completion of the first phase.

As for the definition of a state of cold shutdown, the government said that the bottom part of a reactor's pressure vessel should be basically kept at 100 C or below, and that radiation exposure caused by the additional release of radioactive substances should be ''greatly restrained.''

At present, the maximum amount of such substances leaking from the damaged Nos. 1 to 3 reactors is 1 billion becquerels per hour, around one two-millionth of the level at the time of the accident, the utility known as TEPCO said.

Based on the data, the maximum radiation dose amounts to 1.7 millisieverts per year around the plant, and TEPCO is expected to bring the level to below the legal limit of 1 millisievert per year, an official at the government's Nuclear and Industrial Safety Agency said.

TEPCO also said it will try to improve the operational ratio of water decontamination devices from around 70 percent of capacity this month as well as consider creating another system as the current water treatment system can be used for only about a year.

The utility plans to design an underground wall, expected to extend 30 meters deep, to prevent contaminated water from seeping from the reactor and turbine buildings and getting mixed with groundwater, it said.

Restoration efforts have continued since the March 11 magnitude 9.0 earthquake and tsunami hit the six-reactor complex and led the cooling functions of the reactors and spent nuclear fuel pools at the Nos. 1 to 4 units to fail.

One of the key challenges during the past months has been how to deal with the massive amount of highly radioactive water that has accumulated in the reactor turbine buildings and nearby areas as an outcome of an emergency measure to continue injecting water into the reactors to cool the fuel inside.

Nitrogen, an inert gas, is also being injected into the reactors to prevent hydrogen explosions, which could lead to the release of massive amounts of radioactive substances. But basically all the spent fuel tanks of the Nos. 1 to 4 units are already being kept cool.

==Kyodo
english.kyodonews.jp