In the videos, then-plant chief Masao Yoshida complained about phone calls to the prime minister’s office not getting through and showed frustration as he fought the government’s nuclear safety officials interfering with technical suggestions that didn’t fit the plant’s conditions.
Around 11 a.m. on March 15, Yoshida screamed to officials at Tokyo headquarters: “The headquarters! This is serious, this is serious. The No. 3 unit. I think this is hydrogen explosion. We just had an explosion.” In the video’s background, other officials shout questions, asking for radiation levels and other data.
The videos also included conversations showing communication problems between the plant and the government, workers’ lack of knowledge in emergency steps and delays in effort to inform outsiders about the risks of leaking radiation.
So the real question is why the company didn't move more quickly since 2008 to strengthen defenses at the plant. That article gives some insight into why that didn't happen, but it's partly because of the collusion between the nuclear industry and regulators, complacency on the part of the company, etc.
In 2008, Tepco engineers made three separate sets of calculations that showed that Fukushima Daiichi could be hit by tsunamis as high as 50 feet, according to the company. A Tepco spokesman, Takeo Iwamoto, said Tepco did not tell regulators at NISA for almost a year, and then did not reveal the most alarming calculation, of a 50-foot wave, until March 7 of last year — four days before the tsunami actually struck.
Asked why the company did not move more quickly to strengthen defenses at the plant, he said that the calculations were considered “provisional estimates” based on academic theories that were not then widely accepted.