struck the plant was double the height of the highest wave predicted by officials. The erroneous assumption that the plant's cooling system would function after the tsunami worsened the disaster. "Plant workers had no clear instructions on how to respond to such a disaster, causing miscommunication, especially when the disaster destroyed backup generators." In February 2012, the Rebuild Japan Initiative Foundation described how Japan's response was hindered by a loss of trust between the major actors: Prime Minister Kan, TEPCO's Tokyo headquarters and the plant manager. The report said that these conflicts "produced confused flows of sometimes contradictory information". According to the report, Kan delayed the cooling of the reactors by questioning the choice of seawater instead of fresh water, accusing him of micromanaging response efforts and appointing a small, closed, decision-making staff. The report stated that the Japanese government was slow to accept assistance from U.S. nuclear experts. A 2012 report in The Economist said: "The operating company was poorly regulated and did not know what was going on. The operators made mistakes. The representatives of the safety inspectorate fled. Some of the equipment failed. The establishment repeatedly played down the risks and suppressed information about the movement of the radioactive plume, so some people were evacuated from more lightly to more heavily contaminated places." From 17 to 19 March 2011, US military aircraft measured radiation within a radius of the site. The data recorded 125 microsieverts per hour of radiation as far as northwest of the plant. The US provided detailed maps to the Japanese Ministry of Economy, Trade and Industry (METI) on 18 March and to the Ministry of Education, Culture, Sports, Science and Technology (MEXT) two days later, but officials did not act on the information. The data were not forwarded to the prime minister's office or the Nuclear Safety Commission (NSC), nor were they used to direct the evacuation. Because a substantial portion of radioactive materials reached ground to the northwest, residents evacuated in this direction were unnecessarily exposed to radiation. According to NSC chief Tetsuya Yamamoto, "It was very regrettable that we didn't share and utilize the information." Itaru Watanabe, an official of the Science and Technology Policy Bureau of the technology ministry, said it was appropriate for the United States, not Japan, to release the data. Data on the dispersal of radioactive materials were provided to the U.S. forces by the Japanese Ministry