In April when it nonchalantly raised the INES level of Fukushima I Nuclear Plant accident to "Level 7", the Nuclear and Industrial Safety Agency (NISA) said the total amount of radioactive materials (iodine and cesium) released into the atmosphere from the plant was 370,000 terabequerels.
Now it's been revised to 850,000 terabecquerels, 130% jump from 370,000.
Why the revision? NISA says it underestimated the release from the Reactors 2 and 3.
And remember, the contaminated water at Fukushima I Nuke Plant contains 720,000 terabecquerels of radioactive iodine and cesium.
Slowly and steadily approaching Chernobyl.
From Mainichi Shinbun English (6/7/2011):
The Nuclear and Industrial Safety Agency (NISA) on June 6 revised the level of radioactivity of materials emitted from the crisis hit Fukushima No. 1 Nuclear Power Plant from 370,000 terabecquerels to 850,000 terabecquerels.
The Cabinet Office's Nuclear Safety Commission of Japan (NSC) had estimated that the total level of radioactivity stood at around 630,000 terabecquerels, but this figure was criticized as an underestimation. NISA officials plan to present the new figure at a ministerial meeting of the International Atomic Energy Agency (IAEA) after reporting it to the NSC.
The NSC and NISA, which operates under the Ministry of Economy, Trade and Industry, announced a figure for the total amount of radioactivity on April 12, when the severity of the Fukushima nuclear crisis on the International Nuclear Events Scale was raised to level 7, matching that of the Chernobyl nuclear accident. In the Chernobyl accident, the total amount of radioactivity reached 5.2 million terabecquerels.
The NSC calculated the amount of radioactive materials released into the air between the outset of the crisis and April 5, based on the amount of radiation from measurements taken near the plant. NISA based its calculations on the state of the plant's reactors.
The latest figure takes into consideration the release of radioactive materials during explosions at the plant's No. 2 and 3 reactors. The INES scale designates leaks of tens of thousands of terabecquerels as level 7 events, and the seriousness of the disaster on the scale will not change as a result of NISA's revision of the amount.