AFP, Feb 22, 2015 (emphasis added): Sensors at the Fukushima nuclear plant have detected a fresh leak of highly radioactive water into the sea… [with] contamination levels up to 70 times greater than the already-high radioactive status seen at the plant… TEPCO said its emergency inspections of tanks storing nuclear waste water did not find any additional abnormalities… It was not immediately clear what caused the original spike… “With emergency surveys of the plant and monitoring of other sensors, we have no reason to believe tanks storing radioactive waste water have leaked… We are currently monitoring the sensors”…  The latest incident, one of several that have plagued the plant in recent months, reflects the difficulty in controlling and decommissioning the plant… TEPCO has not been able to effectively deal with an increasing amount of contaminated water…

NHK, Feb 22, 2015: Fukushima radioactive contamination sets off alarm — [TEPCO] says it has detected high levels of radioactive substances in a drainage channel on the plant’s premises on Sunday… the plant’s alarm system went off around 10 AM… levels of beta-ray emitting substances, which are not detected under normal circumstances, had risen to up to 7,230 Becquerels per liter… The utility suspects that contaminated water in the channel may have leaked into the port.

Japan Times, Feb 22, 2015: Strontium-90 levels spike alarmingly at Fukushima No. 1 plant — The Nuclear Regulation Authority said Sunday that an alarm went off at the Fukushima No. 1 nuclear plant signaling high radioactivity levels in drainage ditches… the first alarm sounded at around 10 a.m., and another alarm 10 minutes later indicated much higher levels. Officials said contaminated water may have been discharged into the ditches.

(Link removed) Jiji Press, Feb 22, 2015: Radioactivity Alarm Rings at TEPCO Fukushima Plant

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