Work to remove toxic water puddles in the reactor basements of the crippled Fukushima No. 1 nuclear power plant ground to a halt Sunday after its operator reported a huge spike in radioactivity — a spike that officials later said was inaccurate.
Tokyo Electric Power Co. initially said 2.9 billion becquerels of iodine-134 per cubic centimeter was detected from a puddle in the turbine building of reactor No. 2 on Saturday. The Nuclear and Industrial Safety Agency subsequently announced the figure Sunday morning based on Tepco's report.
Later in the day, however, NISA questioned Tepco's math, prompting the utility to say it had miscalculated.