The radiation plume released by Japan’s damaged nuclear reactors is moving northeast over the Pacific Ocean, Austria’s Meteorological and Geophysics Center reported on its website.
The concentration of radionuclides in the plume cannot be determined because data from the Comprehensive Test Ban Treaty Organization’s Japan detection center were contaminated, according to the report. Agency spokeswoman Annika Thunborg couldn’t confirm the contamination, she said via telephone from Vienna, where the organization is based.
“There was simply some radioactivity in the inside of the station when they dealt with the filter,” Geophysics Center scientist Gerhard Wotawa wrote in response to written questions. “This radioactivity came in from outside, when the plume passed by.” Wotawa formerly worked at the test-ban treaty center and developed its atmospheric-transport modeling system.
Radioactive barium, cesium, iodine and tellurium have been detected in the plume. A “partly dispersed cloud passed by Tokyo area” yesterday, according to the Austrian data center.
The CTBTO was set up in 1996 to detect nuclear-test explosions. Its monitoring system has 63 operating radionuclide centers around the world. The organization plans to build another 17, Thunborg said in a March 15 interview. Countries belonging to the CTBTO receive daily information showing how radiation is moving through the atmosphere and where it is likely to go.
The radiation particles released from the reactor vessels and spent fuel ponds are moving southeast before extending in a northeasterly pattern over the Pacific. Particles may start moving northwest as the winds are expected to shift.
“Populated areas outside the immediate crisis area are currently not directly hit,” the Meteorological and Geophysics Center said.
Two CTBTO centers are located at the Japan Atomic Research Institute in Tokyo. One measures radionuclides, while the other detects noble gases.
Tokyo Electric Power Co. increased its workforce at the crippled Fukushima Dai-Ichi nuclear plant to 322 today from 180 yesterday as it tried to douse water over exposed nuclear fuel rods to prevent melting and leaking lethal radiation. Levels beside the exposed rods would deliver a fatal dose in 16 seconds, said David Lochbaum, a nuclear physicist for the Union of Concerned Scientists and a former U.S. Nuclear Regulatory Commission safety instructor.