NEI Nuclear Notes

TEPCO Injects Nitrogen Into Reactors, Prepares for “Cold Shutdown Condition” December 5, 2011 Plant Status Tokyo Electric Power Co. has begun injecting nitrogen into the pressure vessels of Fukushima Daiichi reactors 1 through 3. The action will reduce any buildup of hydrogen in the reactors as TEPCO prepares to announce, as early as next week, its achievement of what the company calls a “cold shutdown condition.” A new “Ask the Expert” page on NEI’s Safety First website explains how and why TEPCO’s definition of the term differs from common industry usage. TEPCO reported today that about 45 metric tons of water containing radioactive strontium leaked from desalination equipment at a water decontamination facility used to recycle cooling water at the Fukushima Daiichi site. Japan’s Nuclear and Industrial Safety Agency has ordered the company to investigate the causes and report on the impacts should any water reach the ocean and to take steps to prevent future leaks. I...

No two ways about it : Some 45 tons of highly radioactive water leaked Sunday from desalination equipment used to decontaminate the radioactive water in Tokyo Electric Power Co.'s Fukushima No. 1 nuclear plant and it is unclear if any made it to the sea, a Tepco official said Monday. This isn’t good. No radioactive anything should be flowing anywhere at this point and no excuse mitigates it. Having said that, the threat seems low: "Even if all 300 liters reached the sea, the radiation would be diluted, and the amount that escaped is tiny compared with what has already leaked into the sea (on earlier occasions)," said Genichiro Wakabayashi, a radiology professor at Kinki University, playing down the potential danger of the leak. "The leak (even if to the sea or to the groundwater) would not be enough to increase radiation levels in marine or agricultural products in the Tohoku region," he said. He may be “playing down the potential danger” becau...

Several news articles late this week have reported that Japan’s Fukushima Daiichi nuclear plant may be in “cold shutdown” by mid-December. Although the reports are mostly accurate, there is a difference between the traditional “cold shutdown” of a nuclear plant and what is happening at Fukushima. First, what is cold shutdown? The U.S. Nuclear Regulatory Commission defines it as: The term used to define a reactor coolant system at atmospheric pressure and at a temperature below 200 degrees Fahrenheit following a reactor cooldown. In non-nuclear speak, it basically means the conditions within the nuclear reactor are such that it would be impossible for a chain reaction to occur. This term usually comes into play whenever a reactor is shut down periodically for refueling or for the final time prior to the long-term before it is decommissioned. When a reactor is in cold shutdown, the reactor pressure vessel (RPV) can be safely opened with great care and additional water is adde...

From NEI’s Safety First web site : Industry Proposes Integrated Approach on Post-Fukushima Activities December 2, 2011 Industry/Regulatory/Political The industry on Dec. 1 urged the U.S. Nuclear Regulatory Commission staff to consider an integrated and flexible approach toward meeting the NRC’s Fukushima task force recommendations, arguing that this approach would result in faster, more efficient implementation of the most safety-significant recommendations. The industry advocated enhancing the post-9/11 concept of using portable equipment to address loss of all AC power and loss of ultimate heat sink from a variety of natural phenomena. This enhanced mitigation action—called a “diverse and flexible mitigation capability”—could be supplemented by regional response centers that could provide additional hardware and equipment to further extend coping capability should there be a longer-term loss of power or cooling capability. Tokyo Electric Power Co. (TEPCO) today releas...

Does America Online still exist? Why, yes it does, though it seems to have changed its business model considerably – it isn’t supporting the CD-manufacturing industry all by itself anymore, for one thing. It also has an energy site , at which we learn: The headlines should come somewhere between December and March 2012 when the Nuclear Regulatory Commission, if all goes as expected, will okay building up to four new nuclear reactors. The licenses for two Westinghouse AP1000 reactors at Southern Co.'s Plant Vogtle in Georgia, followed quickly by two more at SCANA's Summer station in South Carolina, will be the first granted since the 1970s. The story following is notably positive. One plus for new nuclear is new jobs. Both the Vogtle and Summer sites will employ thousands of construction workers, as well as hundreds of operational personnel when the units start up 2016-19. Fertel said that, while the largest reactor components have to be forged overseas since no facilities ex...

Early on Wednesday morning, the Dow Jones News Wire first reported the following from Japan , before the rest of the mainstream media got hold of the story today: The melted nuclear fuel within the No. 1 unit at the Fukushima Daiichi power plant was of such intensity that it eroded through 2 meters of the 2.6 meter (8.5 feet) concrete base, plant operator Tokyo Electric Power Co. said in a report issued on Wednesday.  Yesterday here at the office, we huddled with a representative of TEPCO to get a better understanding of the report, and share some additional facts that puts this information into the proper context. What's been reported is a very conservative mathematical analysis that has yet to be physically confirmed. In other words, this is a worst case scenario. And as we've seen in our industry, even in the worst case scenario, there is still a very significant safety margin. A quick read of the article could give one the impression that the melted core was a little ...

We always have time for some good news: A three-judge panel at the U.S. Nuclear Regulatory Commission (NRC) denied a filing by Massachusetts to stop the relicensing of Entergy's 685-megawatt Pilgrim nuclear power plant in Massachusetts. This had never seemed a good bet for Massachusetts, which had based its contention on events at Japan’s Fukushima Daiichi. Since the NRC is working to apply lessons learned from Fukushima to the American fleet, the state’s contention seemed irrelevant. But – there are further steps to be taken: The NRC said the state could appeal the ASLB ruling against its Fukushima contention to the five-member, presidentially appointed Commission that oversees the NRC. The ASLB is is the Atomic Safety and Licensing Board , which handles these issues. It was the ASLB that created a minor tempest when it ruled the Department of Energy could not withdraw its license application for Yucca Mountain from the NRC. This is smaller in scope, but an important step to...