Fukushima related items of the day .....

Dry Vent of Reactor 2 May Have Released Largest Amount of Radioactive Materials, Not Explosions

The paper by a Tokyo University researcher that was finally published nearly one year after he took the samples at the front gate of Fukushima I Nuclear Power Plant and in Iitate-mura in Fukushima Prefecture (see my post from yesterday) has this very interesting chart.

It shows the spacial dose of radiation at the front gate of Fukushima I Nuke Plant and the timeline of events at the plant in March. The largest spike seems to be around or after 12AM on March 15, and the label on the spike says "Dry vent at reactor no.2".

On checking the information from March 2011, I find that TEPCO did the dry vent at Reactor 2 at 12AM on March 15, 2011 for a few minutes. At first (on March 20), TEPCO announced they'd done the dry vent sometime on March 16 and 17, but on March 21 retracted that statement and said the dry vent was done at 12AM on March 15. (See Sankei Shinbun article on 3/21/2011.)

It is not clear whether the company informed the residents or the government before the the Reactor 2 dry vent on March 15 which caused a huge spike in radiation, and which may be the biggest contributor to radiation contamination in wide areas in Tohoku and Kanto. From the Sankei article it doesn't look like they gave any prior notice. This is the same company that didn't even tell the plant workers that the vent on Reactor 1 was about to be carried out on March 12.

Dry vent releases different types of radioactive materials compared to wet vent.

The peak that appears to the right side of the largest peak is after the hydrogen explosion of Reactor 4, but not at the time of explosion. I suspect the peak may have been the result of some event on Reactor 2's Suppression Chamber which seems to have taken place about the same time as the Reactor 4 hydrogen explosion. TEPCO says it was not "explosion" that happened at the Reactor 2 Suppression Chamber but still doesn't say what it was.

The second largest peak was when the fire broke out on Reactor 3 on March 16. The white smoke was seen at 8:30AM on March 16, and the radiation level at the front gate of the plant shot up to 10,000 microsieverts/hour (10 millisievert/hour) at 10:40AM (Asahi Shinbun 3/16/2011).

Again, it is just too bad that the researcher had to sit on the data for 11 months for his article to be published in a peer-review magazine.

and.....

http://fukushima-diary.com/2012/03/japanese-debris-has-already-arrived-at-west-coast-of-united-states/

Japanese debris has already arrived at west coast of United States

Posted by Mochizuki on March 5th, 2012 · No Comments

Fishers bobs and the debris written Japanese are frequently found in west cost of United states, where is 7300km away from Japan.

Last weekend, citizens had exhibition of driftage in the coast of North west Washington.
The U.S. National Oceanic and Atmospheric Administration states, all the driftage are mixed in north pacific ocean, can’t distinguish which one is the debris because of Tsunami,
but the a citizen talks, he has been picking up driftage since 1976, there had been 4 items, but has picked up 15 ones in these 2 months.
Local people are concerned about the environmental and biological effects, they want to return when they can identify the owner.

Source
太平洋を漂流する東日本大震災のがれきの一部、アメリカ西海岸に到達ではとの報告相次ぐ
フジテレビ系（FNN） 3月5日(月)13時17分配信
太平洋を漂流する東日本大震災の津波によるがれきの一部が、7,300km余り離れたアメリカ西海岸に、すでに到達したのではという報告が相次いでいる。
ワシントン州北西の海岸で週末、地元住民が、海からの漂流物を持ち寄った。最近、漁業用の浮きの数が急増していることや、日本語での記載が多く見られることが話題となっている。

発泡スチロールには、「特定フロンは使用していません」と書かれていて、断面は比較的新しかった。
住民は「1976年から、海岸の漂流物を収集してきて、それまで4つ拾った。ところが、ここ2カ月で15個も拾った」と話した。
しかし、気象当局の担当者は、津波によるものとは、まだ断定できないとしている。
米海洋大気庁漂流物担当者は「全ての漂流物が北太平洋で混ざるから、どれが津波によるものとは断定できない」と述べた。
地元住民は、環境や生態系への影響に懸念を示しているが、持ち主が判明する場合は、返却していきたいとしている。
最終更新:3月5日(月)13時47分