"not high enough to warrant a cleanup"

Metro gov't denies Tokyo park needs radiation decontamination

http://mainichi.jp/english/english/newsselect/news/20120613p2a00m0na014000c.html 

The Tokyo Metropolitan Government has rejected a local politician's call to decontaminate a park where high concentrations of radioactive cesium have been detected, saying radiation levels are not high enough to warrant a cleanup.

The high concentrations in Katsushika Ward's Mizumoto Park were found earlier by Japanese Communist Party (JCP) members of the metropolitan assembly, and JCP assemblyman Tamio Tazoe called for the decontamination of the site in a recent session. The metropolitan government, which detected a radiation dose of 0.99 microsieverts per hour in tests at the park on June 11, rejected Tazoe's request, stating the emissions did not reach the national limit.

According to the Tokyo Bureau of Environment, it conducted the June 11 measurements at the request of the Ministry of Education, Culture, Sports, Science and Technology (MEXT), which had been contacted by the JCP. It says bureau workers took the 0.99 microsieverts per hour reading a meter above the ground where the JCP members had earlier found the high cesium concentrations. About 60 meters away in the middle of the park's parking lot, however, the bureau says it measured a dose of just 0.18 microsieverts per hour.

In October last year, the national government established standards whereby MEXT could be contacted if localized radiation levels were on average one microsievert per hour higher than surrounding areas.

Bureau chief Teruyuki Ono stated that the measurements taken this time were below the national limit and that he thought an overall radiation survey of Tokyo government facilities was "basically unnecessary."