The Nuclear Regulatory Commission released a collection of transcripts of internal conference calls held in the initial hours after the Fukushima Daiichi nuclear disaster in the earthquake in Japan, which reveal a sense of urgency and confusion that the situation generated.

I want to be clear, the early hours of the first day or two were very hectic, NRC Chairman Gregory Jaczko said to reporters. There was not a lot of information. Much of what we knew came from a variety of sources -- some from the Japanese, some from the IAEA (International Atomic Energy Agency) and a great deal from the news media, he added.

In the situation in Japan, normal power supplies from the electricity grid were cut by the earthquake and the subsequent tsunami resulted in a flood that rendered backup diesel generators inoperative.

NRC officials said that the agency’s assessments about radioactivity release turned out to be substantially correct in the end because of releases from three of the reactors.

The transcripts were released in response to a Freedom of Information Act request and are available on the agency’s Web site here.

NRC got some of its information from the Japanese government and the Tokyo Electric Power Company. The agency remained heavily dependent on news releases and media reports, especially in the first days of the crisis.

Presently there is a debate going on for the lessons the U.S. should draw for its power plants from the activities relating to the nuclear emergency situation in Japan. The manner in which the U.S. will be handling a similar situation has gained much prominence recently.