Tag Archives: Venting Radiation

Japan backs off venting of leaking Japan reactor

18:10 JST March 20: The operator of Japan’s overheating, leaking nuclear plant backed off a tricky venting of radioactive gas from a troubled reactor Sunday as concerns grew about wider contamination of food and water.

After the cascading troubles at the Fukushima plant appeared to lessen Saturday, pressure inside the vessel holding the reactor of Unit 3 rose again Sunday, dealing a setback to the government and forcing officials to consider the dangerous venting. Nuclear safety officials said one of the options could release a cloud dense with iodine as well as the radioactive elements krypton and xenon.

The plant’s operator, Tokyo Electric Power Co., temporarily suspended the plans Sunday after the pressure inside the reactor stopped climbing, though it was at a relatively high level.

"It has stabilized," Tokyo Electric manager Hikaru Kuroda told reporters. Kuroda said temperatures inside the reactor reached 572 Fahrenheit (300 degrees Centrigrade) and the option to release the highly radioactive gas inside – a maneuver he called a "dry vent" – is still under consideration if pressure rises.

The higher reactor pressure may have been caused by a tactic meant to reduce temperatures – the pumping of seawater into the vessel, Kuroda said.

Using seawater to douse Unit 3 and the plant’s five other reactor vessels or their nuclear fuel storage pools was a desperate measure since it’s corrosive, damaging the finely milled machine parts. The government acknowledged Sunday that the entire complex would be scrapped once the emergency is resolved.

"It is obviously clear that Fukushima Dai-ichi in no way will be in a condition to be restarted," Chief Cabinet Secretary Yukio Edano told reporters.

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Quake-hit Japan nuclear plant faces fresh threat

Japan battled to contain a radiation leak at an earthquake-crippled nuclear plant on Sunday, but faced a fresh threat with the failure of the cooling system in a second reactor.

Operator TEPCO said it was preparing to release some steam to relieve pressure in the No.3 reactor at the plant 240 km (150 miles) north of Tokyo — which would release a small amount of radiation — following an explosion and leak on Saturday in the facility’s No. 1 reactor.

As strong aftershocks continued to shake Japan’s main island the desperate search for survivors from Friday massive earthquake and tsunami continued, and the death toll was expected to rise.

Thousands spent another freezing night huddled over heaters in emergency shelters along the northeastern coast, a scene of devastation after the 8.9 magnitude quake sent a 10-meter (33-foot) wave surging through towns and cities.

Kyodo news agency said the number of dead or unaccounted for as a result of the quake and tsunami was expected to exceed 1,800. It also reported there had been no contact with around 10,000 people in one small town, more than half its population.

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