High levels of cesium found at former nuclear lab outside L.A.
LOS ANGELES (Kyodo) -- High levels of radioactive cesium have been detected on the ground of a former nuclear facility in the suburbs of Los Angeles called the Santa Susana Field Laboratory, where an experimental nuclear reactor suffered fuel melting in 1959, according to U.S. government data obtained Thursday.
The data, provided to local residents in February as an interim report by the Environmental Protection Agency, which is examining the extent of contamination in the area, show that radioactive cesium measured up to about 7,300 becquerels per kilogram of soil, or nearly 1,000 times the benchmark used by the agency.
The area was decontaminated after the nuclear accident, and the U.S. Department of Energy, which was dealing with research there, declared in the 1980s that the land could now be used as farmland or for residential purposes.
The decision to conduct a detailed study was made in December 2010 after strong demands were lodged by local residents who have expressed health concerns for a long time.
The findings suggest that the Department of Energy had grossly underestimated the level of contamination in the area and have shown the difficulty of cleaning up soil contaminated with radioactive materials.
In Japan, which was hit by meltdowns at a nuclear power plant last March and the subsequent release of massive amounts of radioactive materials, rice cannot be grown in paddies if radioactive cesium detected there measures more than 5,000 becquerels per kg of soil.
The EPA sampled soil at 437 spots near the area where the troubled reactor used to be, and found higher levels of radioactive materials than normal at 75 of them. At seven spots, cesium measured over 100 times the standard, with the maximum reading of 957 times the standard.
The agency is expected to announce its results by the end of this year, with plans to finish decontamination work by 2017.
In the July 1959 accident, 13 of the 43 fuel rods partially melted after an experimental sodium coolant reactor suffered malfunctions. No one is believed to have died directly from the accident, which was the first fuel melting at a facility in the United States that provided electricity to the private sector.
The lab has also been known for its sloppy management of hazardous materials, having incinerated radioactive waste in an open yard at the site for two decades.
Accidents have periodically occurred at nuclear facilities in the United States, which has large nuclear weapons stockpiles and many nuclear reactors, but no accident or contamination as serious as the one at the Santa Susana Field Laboratory has occurred near a city as populous as Los Angeles, the second largest city in the country.