Typhoon hits Fukushima as TEPCO releases radioactive water into sea 16 Sep 2013 Typhoon Man-yi hit Japan Monday, leaving two people dead and forcing the operator of the crippled Fukushima nuclear plant to release rainwater with low levels of radiation into the ocean. The powerful typhoon made landfall in Toyohashi, Aichi prefecture, shortly before 8:00 am (2300 GMT Sunday), packing gusts of up to 162 kilometres (100 miles) per hour, the Japan Meteorological Agency said. The typhoon also hit the northeast, including the Fukushima area, bringing heavy rain to areas near the broken plant run by Tokyo Electric Power (TEPCO). Workers were pumping out water from areas near tanks storing radioactive water, from which leaks are believed to have seeped into groundwater. According to the spokesman, one litre of the water contained up to 24 becquerels of strontium and other radioactive materials -- below the 30 becquerel per litre safety limit imposed by Japanese authorities for a possible release to the environment. However, it was unknown how much [radioactive] water was released to sea under the "emergency measure," Koshimizu said.
Pilgrim plant powers up to 70 percent
PLYMOUTH — Pilgrim Nuclear Power Station was back online and operating at 70 percent of its power capacity by midday Monday, after a weeklong shutdown caused by a steam leak in a heater line to the reactor.
Entergy, the owner-operator, fixed the leak and began firing up the plant Sunday night.
But Pilgrim will remain at 70 to 75 percent of capacity until problems with one of three massive pumps that supply water to the nuclear reactor are also cleared up.
Neil Sheehan, spokesman for the Nuclear Regulatory Commission, confirmed Monday that a feedwater pump, down since Aug. 22, was not yet back in service.
"Once that occurs, we will have a better sense of whether the repair work was fully successful," Sheehan wrote in an email. "Pilgrim needs all three main feedwater pumps in service to achieve full power."
NRC inspectors, assigned to Pilgrim full time, "will continue to monitor plant conditions as the reactor gradually ascends in power to the 100 percent level," he said.
Carol Wightman, spokeswoman for Entergy, said in an email that modifications were made to the power supply for the feedwater pump.
"[We] will be performing additional testing as part of our power ascension program," she wrote.
Pilgrim has not operated at full power since Aug. 22, when a breaker tripped, cutting power to the three feedwater pumps. Operators immediately shut down the plant.
A faulty wiring cable was initially determined to be the cause of the breaker trip, but when the plant was restarted on Aug. 26, only two of three pumps functioned.
Plant operators then decided the motor in the third pump had burned out and they replaced it. The pump still failed.
Circuitry related to the pump was thought to be the problem.
While the NRC appeared satisfied with the Pilgrim plant in its mid-year performance review, Sheehan said the recent plant shutdowns didn't factor into that evaluation.
The NRC is still considering whether there will be stricter federal oversight at Pilgrim because of the number of unplanned shutdowns. Any decision to boost oversight would be part of the NRC's third quarter report, due out next month.
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