November 2011

Plant Status

  • The trace of radioactive xenon found earlier this week in reactor 2 at Fukushima Daiichi is too small to have resulted from a criticality incident in the reactor, Tokyo Electric Power Co. (TEPCO) has concluded. The company said yesterday that the small amount of xenon-135 detected in a gas sample taken from the reactor 2 containment vessel resulted from the spontaneous fission of curium-242 and -244, which are found in nuclear fuel. Spontaneous fission is a form of radioactive decay that does not lead to a chain reaction. A criticality event would have resulted in higher levels of xenon, TEPCO said. Japan’s Nuclear and Industrial Safety Agency will evaluate the results.
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Employees Training in a Control Room Simulator

Employees Training in a Control Room Simulator

Responding to Fukushima: Part 5 of a 5-Part Series

Though the Nuclear Regulatory Commission (NRC) concluded that America’s nuclear energy facilities are operating safely, the NRC and the nuclear energy industry agree that adapting lessons learned from the incident in Japan will require the review of current emergency operating guidelines and procedures. If new guidelines and procedures are developed, implementing them successfully will require additional training for industry workers.

Constant training has been a hallmark of the American nuclear industry. Before the NRC licenses an individual to operate or supervise operators of a nuclear power reactor, he or she must have several years of related experience and complete extensive classroom, simulator and on-the-job training. After that, reactor operators spend every fifth week training in a full-scale simulator that is the exact replica of each plant’s control room.
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Enrico Fermi Nuclear Generating Station  Responding to Fukushima: Part 4 of a 5-Part Series

Containment vents play an important role in the overall safety strategy at nuclear energy facilities by preventing the potentially hazardous buildup of pressure from steam and gases inside a reactor. A specially designed vent in the massive containment dome that surrounds a reactor is designed to withstand extreme events by relieving primary containment pressure to a stack or other elevated release point.

Boiling water reactors with Mark I containment structures, the type of reactor at Japan’s Fukushima Daiichi facility, have a proven record of more than 40 years of safe and reliable operations.  Twenty-three of this type of reactor in the United States are equipped with these specially designed vents. Although vent valves are rarely used—they’ve never been needed during five decades of operation at U.S. reactors—the events in Japan highlighted the need to ensure that they would function even in the most unlikely circumstances.
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Monitoring Used Nuclear Fuel Pools

Responding to Fukushima: Part 3 of a 5-Part Series

The events at Fukushima unveiled an important lesson to the nuclear industry on the need to remotely monitor water temperature and levels in used fuel storage pools during an extended loss of power. In particular, when power was lost at Japan’s Fukushima Daiichi reactors, the systems the plant relied on to monitor the used fuel pools were inoperable. That loss led some to erroneously conclude that there was no water in the spent fuel pool at reactor 4—a conclusion that was later proven to be false.

The industry supports the Nuclear Regulatory Commission’s (NRC) recommendation that U.S. nuclear energy facilities enhance used fuel pool monitoring instrumentation. The storage pools protect used fuel rods under 40 feet of water to allow radioactivity in the fuel to safely decrease. Adding backup monitoring equipment enables operators to know when they need to take action to maintain water level and temperature of used fuel storage pools in the unlikely event that installed systems have been disabled.
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Plant Status

  • Workers at the Fukushima Daiichi nuclear energy facility have taken steps to halt the possibility of localized fission reactions in reactor 2 after detecting trace amounts radioactive xenon in the reactor’s containment vessel, NHK World reports. Xenon is a byproduct of fission. Tokyo Electric Power Co., which operates the facility, reports no significant changes in temperature, pressure and other data from the reactor.
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Activity ID: 1002943 Activity Name: NEI Remarketing Safety Activity Group Name: Remarketing Safety First