Showing posts with label gamma camera. Show all posts
Showing posts with label gamma camera. Show all posts

Friday, February 22, 2013

#Fukushima I Nuke Plant: Gamma-Ray Camera Image of Reactor 2 Operating Floor


As the new LDP administration under Shinzo Abe is very eager to be done with the Fukushima nuclear accident by urging TEPCO to do the decommissioning work way ahead of schedule (which is not feasible even its current form), TEPCO dutifully follows the government prompting (which is tantamount to an order without saying it is an order).

The effort to do things ahead of schedule, or to catch up on the behind-schedule work, has already resulted in dropping a fuel transfer machine part into the Spent Fuel Pool in Reactor 3 as the workers carried out the work in heavy snow.

Now, TEPCO just did the gamma-ray imaging of the Reactor 2 operating floor. Although the Reactor 2 building looks intact except for the open blowout panel, the radiation levels on the operating floor is just too high for the carbon-based or silicon-based workers. The lowest level is 40 millisieverts/hour, the highest 880 millisieverts/hour right above the reactor well, as mapped by the robot Quince No.2 in June last year.

What TEPCO did therefore was to build a platform on top of the turbine building to the height of the blowout panel, and lifted up the gamma camera onto the platform using a crane.

TEPCO says the analysis will take about a month.

From TEPCO's Photos and Videos Library, 2/22/2013:


According to the handout that accompanies the photo, TEPCO plans to "decontaminate" the floor whose air radiation doses are as high as 880 millisieverts/hour in order to remove fuel assemblies from the Spent Fuel Pool in the "future".


At a much lower air dose level of about 10 millisieverts/hour, Quince No.1 robot has been stranded on the 3rd floor of Reactor 2 since October 2011.

I have no idea how "decontamination" is possible.

Saturday, June 11, 2011

#Fukushima I Nuke Plant Reactor 3 Gamma Camera Photos


Compared to the Reactor 1 gamma camera photos, the numbers for the Reactor 3 are markedly higher. Measurement unit is not noted in the photos, but if it is the same as those for the Reactor 1, it is counts per second (cps).

The location 2 is right below the Spent Fuel Pool, I've been informed.

Location 1 (near the Large Machine Hatch, south side):



Location 2 (west side, below the Spent Fuel Pool):


Sunday, May 22, 2011

TEPCO Releases Gamma Camera Photos of Reactor 1

They were taken on May 20.

From TEPCO's "Photos for Press" page:

"From the large equipment service entrance to the south side airlock", regular photo top, gamma camera photo bottom:





"Around the large equipment service entrance", normal photo top, gamma camera photo bottom: