Thursday, July 5, 2012

Fukushima and Japan radiation watch items of note !

Latest Headlines:

Fukushima Daiichi Worker: Tepco is hiding information about leakage of radioactive water from plant

Japan Gov’t: “System must be established to deal with long-term public health effects” of Fukushima disaster — Grave concerns about radiation exposure

NYTimes: Report suggests extensive damage from quake at Fukushima Daiichi — Pipes may have burst leading to loss of cooling within 30 minutes — “Casts doubts on safety of Japan’s entire fleet of nuclear plants”

Minamisoma Official: Highly contaminated black algae observed everywhere — Due to bioaccumulation

Kyodo: Fukushima plant remains vulnerable to quakes -Gov’t

NRC Official: 90% chance that containment vessels used at Fukushima would “burst” from fuel melting down

Japan parliament releases Fukushima report: Disaster was “clearly manmade” — Evidence quake damaged safety equipment, not tsunami

Kyodo Feature: Residents complaining of unexplained hair loss, diarrhea, fatigue around Fukushima plant -Retired Doctor

Asahi: MOX reactor to restart this month in Japan — Nine fault lines run underneath


[Robot decontamination] 0.2 Sv/h on the first floor of reactor3

Tepco is trying to develop the remote decontamination technology by using robot.
They conducted the radiation survey at reactor1 in May [Link].
On 7/5/2012, Tepco announced the radiation survey result of reactor2 and reactor3. (Only the first floor)
It was done from 5/28 to 5/31 in reactor2, from 6/11 to 6/15 in reactor3, but the results have not been published by the day.
The highest reading was 203.1 mSv/h in reactor3, 40.8 mSv/h in reactor2.
Also, they took samples to detect contamination state of those reactors, but the results are not published yet.
Samples of dust, peeling paint and drilling core (of floor) will be analyzed at JAEA Oarai Research and
Development Center. (Unit 1 sample has been sent on June 22,
Unit 2-3 samples will be sent on July 18.)
*  *  *

Fukushima worker “Shortage of nuclear worker is becoming serious”

Actual Fukushima worker Happy11311 is concerned about the shortage of nuclear workers.
Decommissioning of nuclear plant is estimated to take decades.
He tweeted like these below,,

All of the second sub-contract companies to work in Fukushima are struggling with collecting nuclear workers. No benefit is given unlike just after 311. Some of the nuclear workers are paid less than decontamination workers. It seems like Tepco and the first sub-contract companies don’t take the situation too seriously.
I’ve been tweeting about this since last year, but I think the shortage of skillful nuclear workers is becoming real. Especially Fukushima workers can’t get the next job because they have exceeded the yearly dose limit, more and more sub-contract companies will have to be closed. Actually some of the nuclear workers and sub-contract companies are struggling to continue working.


[Reactor1] 5.2 Sv/h on the first floor

Tepco conducted robot survey in reactor1 building TIP room and South area on the first floor. (11:40 ~ 15:47 of 7/4/2012)
Tepco used 4 robots (2 Quinces and 2 PackBots) but couldn’t have them open the door to the TIP room though they managed to insert the key.
[Reactor1] 5.2 Sv/h on the first floor 2
They couldn’t enter TIP room ,but near the penetration area on the floor beside TIP room, they measured 5.15 Sv/h, which was the highest reading in this investigation. This is where the pipe coming through floor.
Last June, steam was observed coming up from this place.
[Reactor1] 5.2 Sv/h on the first floor
7 nuclear workers were involved in the investigation. The planned dosage was 6mSv, but Tepco’s spokesman announced it was 0.76Sv in total. Because this is extremely high level of dosage, we need to verify if it was not misstatement.

You can actually see the white noise of radiation in the pictures.

[Reactor1] 5.2 Sv/h on the first floor 3
↓ Route and radiation level at each point
[Reactor1] 5.2 Sv/h on the first floor 4

[Reactor1] 5.2 Sv/h on the first floor 5
[Reactor1] 5.2 Sv/h on the first floor 6

[Reactor1] 5.2 Sv/h on the first floor 7
For the question “Why Tepco needs to investigate inside of TIP room”, actual Fukushima worker Happy11311 answered like this below,

In TIP room, there are variety of nuclear instrumentation and pipes connected to inside of the vessel, Tepco is seeking the way to look inside of the vessel by using it like they did in reactor2. Also, they need to check if melted fuel comes up through the pipes.