The investigation commission on the Fukushima accident set up by the Cabinet Office of the government has just issued its final report.
You can download your own copy from this page, but the main report in English has to wait.
This commission conducted the investigation and carried out interviews with people involved since the start of the nuclear accident in March last year in private, unlike the National Diet commission who also released its final report recently.
Some have criticized the government commission for not making its sessions open to public. I don't think it is necessarily a bad thing. The National Diet commission should be applauded for its openness and its highly critical final report (anyone reading?), but in some of the public testimonies of the commission that I watched it was rather a place for the expert commissioners to display (or show off) their expertise and knowledge of the nuclear issues in general.
So, will there be information only obtainable in the closed sessions? We'll find out, but someone at Jiji Tsushin has clearly been assigned to read the voluminous report, and he/she has been putting up short articles. Judging from these articles, the government investigation commission is just as critical, if not way more, as the Diet investigation commission. Some of the points from Jiji articles (7/23/2012, here, here and here, in Japanese):
Detailed analysis and timeline from the time the water injection into RPVs failed till the damages to RPVs and Containment Vessels occurred;
Conclusion on how and when the core melt happened and progressed cannot be made because the actual survey at the plant is highly difficult [to say the least...];
Experts from TEPCO, NISA, and Nuclear Safety Commission at the PM's Official Residence failed to provide expert opinion and advice, adding to the distrust by PM Kan of these "in-house" experts;
Head of NISA couldn't answer Kan's question about the precise locations of emergency diesel generators [... should he be asking such details?];
PM Kan decided to go to Fukushima I Nuke Plant on March 12 morning because he (said he) had "the food feel for the place" when it came to technical aspects of nuclear energy;
Communication process was haphazard, direct communication between TEPCO and PM's Official Residence, without NISA's intermediation, had never been assumed or planned;
TEPCO, even though they were well trained and knowledgeable, they critically lacked the ability to think in a flexible and proactive manner;
TEPCO's organization was too vertically segmented to deal with the accident;
TEPCO didn't seem eager to find out what was happening at the plant in the early hours and days of the accident.
If you can think flexibly and proactively and you are curious, you wouldn't be working at TEPCO or NISA (or any ministry or government agency), I'm afraid.
The last Jiji Tsushin article linked above has examples of TEPCO's "inattention" to details and its vertically segmented organization:
From March 12 to 21, nearly 1,000 personal dosimeters were sent to Fukushima I Nuke Plant from Kashiwazaki-Kariwa Nuke Plant in Niigata (operated by TEPCO) and from Shikoku Electric Power Company. However, TEPCO employees didn't ask for [?] the equipment needed [to use those dosimeters], they were never used. Until the end of March, only one dosimeter was available per work group of several workers.
On the first day of the accident on March 11, Masao Yoshida, general manager of the plant, instructed [his managers] to plan for water injection using fire engines. However, because of TEPCO's vertically segmented organization, no one thought it was his job to do so.