TEPCO’s struggle to move radioactive water safely
Japan nuclear safety plans too lax for crowded, quake-prone nation, say nuclear experts The Star, By: Mari Yamaguchi The Associated Press,Apr 08 2013 TOKYO
“…….TEPCO is moving tons of highly radioactive water from the temporary tanks to two similar ones nearby to minimize the leak. They are among seven underground tanks of different sizes which employ the same design.
TEPCO admitted Sunday it had dismissed earlier signs of water loss as within a margin of error and waited until a spike in radiation levels around the tanks was detected. Critics suspect cash-strapped TEPCO built poorly designed underground pits instead of safer and more manageable steel tanks to save money. TEPCO has also been criticized for delaying replacement of makeshift equipment, raising questions about whether the plant is really under control.
The underground tanks, several times the size of an Olympic swimming pool and similar to an industrial waste dump, are dug directly into the ground and protected by double-layer polyethylene linings inside an outermost clay-based lining, with a felt padding between each layer. Officials suspect there were ruptures in the linings due to the weight of the water.
Contaminated water at the plant, which suffered multiple meltdowns after the 2011 disaster, has escaped into the sea several times during the crisis. Experts suspect a continuous leak into the ocean through an underground water system, citing high levels of contamination in fish caught in waters just off the plant.
The contaminated water in the tanks is part of more than 270,000 tons of water used to cool melted fuel at the plant’s reactors damaged in the disaster. So much water has been used that TEPCO is struggling to find storage space. The water is also kept in hundreds of steel tanks.
NRA commissioner Toyoshi Fuketa told reporters Monday that the water leak poses a more immediate threat to the plant’s water management than to the environment. He questioned TEPCO’s risk evaluation in the tanks’ design process, but acknowledged that regulators have to allow TEPCO to use the remaining underground tanks for now.
“Although we need more long-term plans, we have to tackle the most immediate problem first. TEPCO’s decommissioning process is a tightrope situation to begin with,” he said. http://www.thestar.com/news/world/2013/04/08/japan_nuclear_safety_plans_too_lax_for_crowded_quakeprone_nation_say_nuclear_experts.html
Nuclear reactors become more dangerous as they age
Nuclear facilities are licensed to operate for forty years and all have experienced age-related degradation before the termination of their original license. Despite this, the NRC continues to extend licenses to facilities throughout the U.S.
from 1952-2009 there have been 99 major nuclear power station incidents worldwide.
NUKE MATTERS: Three Mile Island, Chernobyl, Fukushima…Plymouth?
http://www.wickedlocal.com/plymouth/news/opinions/x35738056/NUKE-MATTERS-Three-Mile-Island-Chernobyl-Fukushima-Plymouth#axzz2CQF4Vofv By Karen Vale, Campaign Coordinator, Cape Cod Bay Watch Wicked Local Plymouth, 18 Nov 12, Three Mile Island in 1979, Chernobyl in 1986, and most recently Fukushima – these catastrophic nuclear accidents thrust the debate about the safety of nuclear power into the public
spotlight.
Fukushima also triggered a critical examination of nuclear stations with the same type and operational design as the reactors that failed in March 2011. In the U.S., there are 23 reactors with the same design as Fukushima – including Pilgrim Nuclear Power Station
(Pilgrim) on Cape Cod Bay in Plymouth. Read more »
USA nuclear power plants safety precautions
Hurricane Sandy and N.J. nuclear power plants: Keeping it cool in high winds http://www.newjerseynewsroom.com/science-updates/nj-nukes-prepare-for-sandy , 28 OCTOBER 2012 BY ROBERT KINKEAD On Sunday, New Jersey’s four nuclear power stations, along with another dozen or so along the Eastern Seaboard,were prepped to deal with Hurricane Sandy as that massive storm crawls up the East Coast toward the Garden State.
Federal regulators require nuclear reactors to be in a safe shutdown condition at least two hours before hurricane force winds strike, according to Alec Marion, VP of nuclear operations at the Nuclear Energy Institute, an energy industry association.
Typically, plant operators begin shutting down reactors about 12 hours before winds exceeding 74 miles per hour arrive. One of the most significant challenges in the shutting down process is keeping the reactor core cool. Read more »
Tasks ahead for Japan’s new nuclear regulatory agency
Nuclear regulatory body faces mountain of urgent tasks http://www.yomiuri.co.jp/dy/national/T120920003922.htm Koichi Yasuda / Yomiuri Shimbun 21 Sept 12, Five members of the new nuclear regulatory commission, headed by Shunichi Tanaka, showed strong determination to ensure the safety of the nation’s nuclear facilities and restore public confidence, based on lessons learned from the crisis at the Fukushima No. 1 nuclear
power plant.
However, the Nuclear Regulation Authority faces a growing number of urgent tasks, including establishing new regulations for nuclear power generation. Read more »
Mihama reactor 2 turns 40 years; future uncertain, Japan Times, Kyodo TSURUGA, Fukui Pref. 27 July 12 — Reactor 2 at the Mihama nuclear power plant in Fukui Prefecture marked its 40th year in operation Wednesday, while the government weighs allowing the now-idled unit to keep running longer than originally planned.
The Nuclear and Industrial Safety Agency last week approved changes in safety regulations to permit reactors to keep running for more than 40 years.
All but two of Japan’s 50 commercial nuclear reactors are now shut down due to safety concerns in the wake of the meltdowns at the Fukushima No. 1 plant in March 2011. Before they can be restarted, the reactors must pass “stress tests” to check their ability to withstand
earthquakes and tsunami.
The 500,000-kw reactor 2 at the Mihama plant, operated by Kansai Electric Power Co., is the third-oldest commercially run reactor in Japan. The two older are reactor 1 at Japan Atomic Power Co.’s Tsuruga plant, also in Fukui, and reactor 1 at the Mihama plant….. http://www.japantimes.co.jp/text/nn20120726a9.html
Australia’s nuclear agencies have poor safety record
Inadequate Safety Practices at Lucas Heights and Inadequate Regulation by ARPANSA, Friends of the Earth 10 Aug 12 Since 2007, a saga has been unfolding regarding contamination accidents at the Australian Nuclear Science and Technology Organisation (ANSTO), ANSTO’s handling of those incidents, ANSTO’s treatment of whistleblowers, the handling of the matter by the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA), and the independence or otherwise of ARPANSA.
The saga has exposed inadequate safety practices at ANSTO and an inadequate performance by the regulator ARPANSA. The problems would not have been exposed and partially rectified if not for a number of ANSTO whistleblowers.
A few snapshots of this saga are noted below and more details can be found on the Friends of the Earth website: Read more »
Removal of Fukushima reactor No 4 fuel rods – long, dangerous process
The pool at No. 4 was behind the secret worst-scenario mapped out by the government, which warned millions of people might have to flee from spewing radiation, including parts of the Tokyo area, which has a population of 35 million people. U.S. authorities have also repeatedly expressed worries about the spent-fuel pool at reactor No. 4.
“If we are asked whether things are completely safe, we cannot say that,” ”If there is another major earthquake, we don’t know what may happen,
Japan removes two nuclear fuel rods from Fukushima plant Times Live Sapa | 18 July, 2012 A giant crane removed two rods packed with nuclear fuel from the Fukushima nuclear plant. This is the beginning of a delicate and long process to deal with a remaining risk of more radiation escaping from the disaster-struck plant. Read more »
Diminishing safety in ‘uprating’ nuclear reactors
nuclear watchdogs have warned that these bigger uprates also carry bigger risks.
“This trend is, in principle, detrimental to the stability characteristics of the reactor, inasmuch as it increases the probability of instability events and increases the severity of such events, if they were to occur,” the Advisory Committee on Reactor Safeguards, which is mandated by Congress to advise the NRC, has warned
How to expand nuclear power without attracting (too much) attention
Washington Times, by Brad Plumer July 18, 2012 Since the 1970s, construction on new nuclear reactors in the United States has largely ground to a halt, thanks to public protests, regulatory obstacles and tight financing. Yet over that same period, U.S. utilities have managed to increase the amount of electricity they get from nuclear power. By quite a lot, in fact.
How is that possible? Through a process known as “uprating.” According to a new analysis by the U.S. Energy Information Administration, the operators of 98 of the country’s 104 commercial nuclear reactors have asked regulators for permission to boost capacity from their existing plants. All in all, the Nuclear Regulatory Commission has approved more than 6,500 megawatts worth of uprates since 1977. That’s the equivalent of building six entirely new nuclear reactors—and during a period when fresh plants were impossible to build. Read more »
San Onofre nuclear plant’s serious safety problems
Made in Japan? Fukushima Crisis Is Nuclear, Not Cultural TruthOut, 14 July 2012 By Gregg Levine, Capitoilette | News Analysis “……..Back at San Onofre, US regulators disclosed Thursday that the damage to the metal tubes that circulate radioactive water between the reactor and the steam turbines (in other words, part of the system that takes heat away from the core) was far more extensive than had previously been disclosed by plant operators:
[Each of San Onofre's steam generators has] 9,727 U-shaped tubes inside, each three-quarters of an inch in diameter.
The alloy tubes represent a critical safety barrier — if one breaks, there is the potential that radioactivity could escape into the atmosphere. Also, serious leaks can drain protective cooling water from a reactor.
Gradual wear is common in such tubing, but the rate of erosion at San Onofre startled officials since the equipment is relatively new. The generators were replaced in a $670 million overhaul and began operating in April 2010 in Unit 2 and February 2011 in Unit 3.
Tubes have to be taken out of service if 35 percent — roughly a third — of the wall wears away, and each of the four generators at the plant is designed to operate with a maximum of 778 retired tubes.
In one troubled generator in Unit 3, 420 tubes have been retired. The records show another 197 tubes in that generator have between 20 percent and 34 percent wear, meaning they are close to reaching the point when they would be at risk of breaking.
More than 500 others in that generator have between 10 percent and 19 percent wear in the tube wall.
“The new data reveal that there are thousands of damaged tubes in both Units 2 and 3, raising serious questions whether either unit should ever be restarted,” said Daniel Hirsch, a lecturer on nuclear policy at the University of California, Santa Cruz, who is a critic of the industry. “The problem is vastly larger than has been disclosed to date.”
And if anything, the Nuclear Regulatory Commission is underplaying the problem. A report from Fairewinds Associates, also released this week, unfavorably compared San Onofre’s situation with similar problems at other facilities:
[SONGS] has plugged 3.7 times as many steam generator tubes than the combined total of the entire number of plugged replacement steam generator tubes at all the other nuclear power plants in the US.
The report also explains that eight of the tubes failed a “pressure test” at San Onofre, while the same test at other facilities had never triggered any more than one tube breach. Fairewinds goes on to note that both units at San Onofre are equally precarious, and that neither can be restarted with any real promise of safe operation….. http://truth-out.org/news/item/10333-made-in-japan-fukushima-crisis-is-nuclear-not-cultural
Japan’s nuclear catastrophe due to reactor design,not to Japanese culture
Made in Japan? Fukushima Crisis Is Nuclear, Not Cultural TruthOut, 14 July 2012 By Gregg Levine, Capitoilette | News Analysis “……..As the Diet’s report makes abundantly clear–far more clear than any talk about Japanese culture–the multiple failures at and around Fukushima Daiichi were directly related to the design of the reactors and to fatal flaws inherent in nuclear power generation.
Return for a moment to something discussed here last summer, The Light Water Paradox: “In order to safely generate a steady stream of electricity, a light water reactor needs a steady stream of electricity.” As previously noted, this is not some perpetual motion riddle–all but one of Japan’s commercial nuclear reactors and every operating reactor in the United States is of a design that requires water to be actively pumped though the reactor containment in order to keep the radioactive fuel cool enough to prevent a string of catastrophes, from hydrogen explosions and cladding fires, to core meltdowns and melt-throughs. Read more »
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