Reactor

The nuclear crisis at the Daiichi complex in Fukushima, Japan, has turned a spotlight on the severe dangers involved in storing spent nuclear fuel in pools. But the danger is not new. In 2003, I cowrote a report with a group of academics, nuclear industry executives, former government officials and other researchers warning that spent fuel pools at U.S. nuclear power plants were vulnerable. The drainage of a pool might cause a catastrophic radiation fire, we reported, which could render an area uninhabitable greater than that created by the Chernobyl accident (roughly half the size of New Jersey)

SEOUL - Escalating the stakes of a standoff with Washington and its allies, North Korea is signaling that it will abandon two decades of negotiations to constrain its nuclear program and will close the door on any deal over its atomic weapons and production facilities. The regime said Tuesday that it would expand all parts of its nuclear arsenal, including reactivating a plutonium-producing reactor complex at Yongbyon shut in 2007 as part of a disarmament agreement. Although restarting the Soviet-era facilities could take more than six months, the announcement sparked concern among world leaders that a miscalculation could lead to military confrontation.

Another fire at Japan's stricken Fukushima No. 1 (Daiichi) nuclear power complex broke out early Wednesday and authorities said about 70% of another reactor's fuel rods had been damaged by the spate of accidents and breakdowns since Friday's earthquake and tsunami. The ominous disclosure, after authorities insisted throughout the previous day that damage to the overheating reactors was negligible, compounded a sense of escalating hazards and fear five days after the disasters expected to take historic peacetime tolls on Japan's people and economy.

Southern California Edison, majority owner of the closed San Onofre nuclear plant, submitted to federal regulators a draft request for a license amendment that would allow the plant to be fired up again before summer. The plant's fate has been a subject of contention since it closed more than a year ago due to excessive wear on steam generator tubes that carry radioactive water. Edison has proposed to restart one of the plant's two units, the one in which the damage was less severe, and run it at 70% power for five months before taking it offline again for inspections.

For the first time since the magnitude 9 earthquake and the tsunami struck Japan nearly two months ago, workers on Thursday entered a damaged reactor at the stricken Fukushima Daiichi nuclear power plant, Tokyo Electric Power Co. said. The recovery team began a project to lower radiation levels by installing six ventilation machines that would absorb isotopes from the air in the No. 1 reactor, said company spokesman Taisuke Tomikawa. Because of the high danger of exposure, teams were expected to spend only 10 minutes at a time inside.

For the first time since the March earthquake and tsunami, workers on Thursday entered the No. 1 reactor at the stricken Fukushima Daiichi nuclear power plant, according to the Tokyo Electric Power Co. The recovery team began a project to install six ventilation machines that would absorb isotopes from the air inside the building, said company spokesman Taisuke Tomikawa. Due to the high risk of radiation exposure, teams were expected to work in shifts inside the reactor. The goal is to lower radiation levels so that workers can replace the facility's cooling systems that were damaged by the tsunami, causing a hydrogen explosion that released damaging radioactivity into the air, soil and water.

Strange, jellyfish-like creatures swarming a coastal nuclear power plant: It might sound like the premise of a cult horror flick, but the invasion has prompted officials at the Diablo Canyon facility in San Luis Obispo to curtail operations for at least a few days. The plant's operator, Pacific Gas & Electric, cut power generation from one of the plant's two reactors to 25% of its capacity, spokesman Tom Cuddy said Wednesday. The other reactor was shut down this week for what PG&E described as routine refueling and maintenance, a procedure that could take about a month.

Japan's nuclear safety agency reported an emergency at a second reactor Sunday in the same complex where an explosion occurred Saturday, according to the Associated Press. Officials at the Nuclear and Industrial Safety Agency told the Associated Press early Sunday that the cooling system had malfunctioned at Unit 3 of the Fukushima Daiichi nuclear plant. Officials said they were informed of the emergency by Tokyo Electric, the utility which runs the plant, according to the Associated Press.

Dangerous levels of radiation escaped a quake-stricken nuclear power plant after one reactor's steel containment structure was apparently breached by an explosion, and another reactor building in the same complex caught fire, Japan's leaders told a frightened population. Authorities warned that people within 20 miles of the crippled reactors should stay indoors to avoid being sickened by radiation. The fast-moving developments at the Fukushima No. 1 (Daiichi) plant, 150 miles north of Tokyo, catapulted the 4-day-old nuclear crisis to an entirely new level, threatening to overshadow even the massive damage and loss of life spawned by a devastating earthquake and tsunami.

An elusive metal screw that worked loose and paralyzed a Bavarian nuclear reactor has defied two weeks of around-the-clock searching and may never be found, a spokesman at the plant said Wednesday. Norbert Eickelpasch said engineers conducting an annual overhaul of the 1,300-megawatt Gundremmingen reactor on the Danube River had discovered that five 15-ounce screws were missing from a water pump in the cooling system.

One of the two reactors at the darkened San Onofre nuclear plant could be restarted at full power and operate safely for almost a year, Southern California Edison officials said Monday. The utility said its analysis confirms that it would be safe to fire up one of the reactors, but that out of an abundance of caution, Edison is proposing running the unit at only 70%. The plant has been shut down since a steam generator tube in the plant's Unit 3 sprung a small leak on Jan. 31, 2012, releasing a small amount of radioactive steam.

Federal regulators have sent Southern California Edison a new set of detailed questions that will help them evaluate the feasibility of a partial restart of the shuttered San Onofre nuclear plant. The plant, which once supplied enough power for about 1.4 million homes, has been out of service for close to a year because of unusual wear on steam generator tubes that carry radioactive water. Edison has requested permission to restart one of two reactor units at the plant and run it at 70% capacity for five months.

Federal regulators grilled Southern California Edison publicly for the first time Friday on its proposal to restart part of the troubled San Onofre nuclear power plant. San Onofre has been out of service for 10 months because of unusual wear on steam generator tubes. A small radiation leak developed as a result and prompted a shutdown in January. The steam generators had been replaced less than two years earlier, costing co-owners Edison and San Diego Gas & Electric a combined $771 million.

The troubles at the San Onofre nuclear power plant brought out hundreds of people Tuesday night for a forum held by the U.S. Nuclear Regulatory Commission. Plant workers and anti-nuclear activists formed warring cheering sections in a ballroom at the St. Regis Monarch Beach hotel in Dana Point as a panel of regulators, ratepayer advocates and residents of nearby communities fielded questions and debated the merits of restarting one of the plant's reactors. San Onofre, which once supplied power to about 1.4 million homes in Southern California, has been out of commission since Jan. 31, when a steam generator tube carrying radioactive water sprang a leak, releasing a minuscule amount of radioactive steam.

The darkened San Onofre power plant will not restart even one of its two reactors for months, the head of the U.S. Nuclear Regulatory Commission said Wednesday. In the meantime, anti-nuclear advocates stepped up pressure to keep the plant shut down, with the release of an analysis showing the issues with San Onofre's steam generators are among the worst in the industry. The plant has been shuttered since Jan. 31, when a tube in one of the plant's newly replaced steam generators leaked, releasing a small amount of radioactive steam, and leading to the discovery that hundreds of other tubes were wearing out more rapidly than expected.

WASHINGTON - The United States and five other countries have agreed to offer a joint proposal to Iran at a high-level meeting next week in an effort to open a path for negotiations to curtail Tehran's disputed nuclear program and to ease the threat of war. When they meet in Baghdad on Wednesday, the six powers will offer to help Iran fuel a small reactor used for medical purposes, and to forgo seeking further United Nations economic sanctions....

Another fire at Japan's stricken Fukushima Daiichi nuclear power complex broke out early Wednesday, compounding the spree of disasters expected to take historic peacetime tolls on the nation's people and economy. The latest blaze broke out in the No. 4 reactor at the nuclear complex on the northeast coast where a plume of radiation escaped Tuesday, sending background radiation levels soaring to degrees that authorities conceded were harmful to anyone with prolonged exposure. With the confirmed dead and known missing topping 10,000 and untold thousands of others suspected to still be buried in the sodden wreckage littering the northeast shores of Honshu island, government leaders urged calm and patience as hardships persisted four days after the worst earthquake in Japan's recorded history.

Strange, jellyfish-like creatures swarming a coastal nuclear power plant: It might sound like the premise of a cult horror flick, but the invasion has prompted officials at the Diablo Canyon facility in San Luis Obispo to curtail operations for at least a few days. The plant's operator, Pacific Gas & Electric, cut power generation from one of the plant's two reactors to 25% of its capacity, spokesman Tom Cuddy said Wednesday. The other reactor was shut down this week for what PG&E described as routine refueling and maintenance, a procedure that could take about a month.