Unit 2 Quince Expedition Analysis

Quince 2 made a trip into Unit 2 and successfully made it back out. A series of images were taken on the refueling floor that give hints at both the condition and the accident at unit 2.

The refueling floor  looks largely unscathed. Work equipment still sits on top of the concrete reactor cap. Work boots sit neatly in a row nearby and tarps are still in place from whatever was being done when the quake hit. Levels inside unit 2 were considered too high for workers to enter.

This set of notes in the timeline gives hints to the time an nature of failures at unit 2:
This is when the cap leaked: • At between 6:00 and 6:10, a large explosive sound occurred. At almost the same time, the pressure of the S/C showed 0 MPa[abs] (Described in “9. Plant Hydrogen Explosion Assessment,” and the explosive sound is believed to have resulted from the explosion at Unit 4).

• Meanwhile, the D/W pressure maintained at 730 kPa[abs] as of 7:20.
• The D/W pressure as of 11:25, which was when the next measurement was made, had decreased to 155 kPa [abs], and it is thought that during this time, the gas in the PCV was released into the atmosphere in some way, and the monitoring car reading near the main gate drastically increased.

Radiation readings inside the reactor building show higher levels around the side of the reactor well where the blow out panel came out. This hints that the containment cap gasket and bellows seal failed on the side near the blow out panel. The failure of the cap gasket did not cause the blow out panel to come off. The panel had come off March 13th, the pressure failures and explosion sounds at 2 were March 15.

Some other things of note we found inspecting the images:
The building itself looks in very good condition on the refueling floor. No cracks or buckled concrete were found.
Equipment sits on top of the reactor concrete cover and work boots sit neatly lined up near the reactor well.
Considerable steam existed in the refueling floor area, paint was peeled off the overhead crane.
Brown residue exists along the fence installed around the spent fuel pool.
The refueling gate area looks undamaged indicating it was not an area of major release from containment.
The refueling crane looks intact and undamaged.

Radiation maps floors 1-5

Images taken by Quince in Unit 2

Reactor cap tightener carousel

Yellow containment cap storage location

Peeling paint on overhead crane

Equipment on reactor well and nearby

fuel gate

refueling gate area close up

Spent fuel pool, refueling crane and loading crane (right)

Residue on spent fuel pool fence

Looking at reactor well

looking towards reactor cap carousel

This article would not be possible without the extensive efforts of the SimplyInfo research team
Join the conversation at chat.simplyinfo.org

© 2011-2023 SimplyInfo.org, Fukuleaks.org All Rights Reserved Content cited, quoted etc. from other sources is under the respective rights of that content owner. If you are viewing this page on any website other than http://www.simplyinfo.org (or http://www.fukuleaks.org) it may be plagiarized, please let us know. If you wish to reproduce any of our content in full or in more than a phrase or quote, please contact us first to obtain permission.


Editor, SimplyInfo.org

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: