reluctance to send bad news upwards, need to save face, weak development of policy alternatives, eagerness to preserve nuclear power's public acceptance, and politically fragile government, along with TEPCO's very hierarchical management culture, also contributed to the way the accident unfolded. Moreover, the information Japanese people receive about nuclear energy and its alternatives has long been tightly controlled by both TEPCO and the government." Poor communication and delays The Japanese government did not keep records of key meetings during the crisis. Data from the SPEEDI network were emailed to the prefectural government, but not shared with others. Emails from NISA to Fukushima, covering 12 March 11:54 PM to 16 March 9 AM and holding vital information for evacuation and health advisories, went unread and were deleted. The data was not used because the disaster countermeasure office regarded the data as "useless because the predicted amount of released radiation is unrealistic." On 14 March 2011 TEPCO officials were instructed not to use the phrase "core meltdown" at press conferences. On the evening of 15 March, Prime Minister Kan called Seiki Soramoto, who used to design nuclear plants for Toshiba, to ask for his help in managing the escalating crisis. Soramoto formed an impromptu advisory group, which included his former professor at the University of Tokyo, Toshiso Kosako, a top Japanese expert on radiation measurement. Mr. Kosako, who studied the Soviet response to the Chernobyl crisis, said he was stunned at how little the leaders in the prime minister's office knew about the resources available to them. He quickly advised the chief cabinet secretary, Yukio Edano, to use SPEEDI, which used measurements of radioactive releases, as well as weather and topographical data, to predict where radioactive materials could travel after being released into the atmosphere. The Investigation Committee on the Accident at the Fukushima Nuclear Power Stations of Tokyo Electric Power Company's interim report stated that Japan's response was flawed by "poor communication and delays in releasing data on dangerous radiation leaks at the facility". The report blamed Japan's central government as well as TEPCO, "depicting a scene of harried officials incapable of making decisions to stem radiation leaks as the situation at the coastal plant worsened in the days and weeks following the disaster". The report said poor planning worsened the disaster response, noting that authorities had "grossly underestimated tsunami risks" that followed the magnitude 9.0 earthquake. The high tsunami that