In the video below, released by TEPCO on September 24, 2012, the accident happens toward the end, at about 3:30. The crane grabber couldn't get a good grip on a relatively small piece of metal right on the edge of the pool, and the metal piece slid into the pool with a small splash. Oops.
There are two video cameras fitted on the boom of the crane.
Looking at the other short video below and the photographs that TEPCO also released on September 24, I can't fault those Kajima workers who are operating these machines and tools by remote control. It looks extremely awkward and difficult to do.
The remote-controlled hydraulic shears cut the metal held by the remote-controlled grabber, both dangling from the crane by wire.
Hydraulic shears (cutter):
Before-and-after photos of Reactor 3 SFP:
The worker who's been tweeting from Fuku-I since March last year said in his tweet that the workers wearing tungsten vests were braving the extremely high radiation and high heat of the summer to clear the debris enough to do the final assemble of the platforms. And he says, "...but no one reported it."
Instead, TEPCO gets comments like "They don't have a shred of credibility", for which I feel sorry for the workers, TEPCO and subcontractors alike.
TEPCO also released the videos of inside the Spent Fuel Pool. See my next post.