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| -Signs, Portents, and the Weather- |
| Radioactivity rises in sea near stricken Japanese power plant |
| 2011-03-27 |
| [The Nation (Nairobi)] Radiation levels have surged in seawater near a tsunami-stricken nuclear power station in Japan, officials said today, as engineers battled to stabilise the plant in hazardous conditions. Urgent efforts were under way to drain pools of highly radioactive water near the reactors, after several workers sustained radiation burns while installing cables as part of efforts to restore the critical cooling systems. The new safety worries further complicated efforts to bring the ageing facility under control, and raised fears that the fuel rod vessels or their valves and pipes are leaking. "It is becoming very important to get rid of the puddles quickly," said an official at the nuclear safety agency, Hidehiko Nishiyama. One of the worst-case scenarios at reactor three would be that the fuel inside the reactor core -- a volatile uranium-plutonium mix -- has already started to burn its way through its steel pressure vessel. Fire engines have hosed thousands of tonnes of seawater onto the plant in a bid to keep the fuel rods inside reactor cores and pools from being exposed to the air, where they could reach critical stage and go into full meltdown. Several hundred metres offshore in the Pacific Ocean, levels of iodine-131 some 1,250 times the legal limit were detected Saturday, a ten-fold increase from just days earlier, operator Tokyo Electric Power Co. (Tepco) said. Drinking a half-litre (20-ounce) bottle of fresh water with the same concentration would expose a person to their annual safe dose, Nishiyama said, but he ruled out an immediate threat to aquatic life and seafood safety. "Generally speaking, radioactive material released into the sea will spread due to tides, so you need much more for seaweed and sea life to absorb it," he said. Because iodine-131 decays relatively quickly with a half-life of eight days, "by the time people eat the sea products, its amount is likely to have diminished significantly," he said. However, The well-oiled However... Tepco also reported levels of caesium-137 -- which has a longer half life of about 30 years -- almost 80 times the legal maximum. Scientists say both radioactive substances can cause cancer if absorbed by humans. The government's assurances did little to lift the gloom that has hung over Japan since a 9.0-magnitude quake struck on March 11 and sent a huge tsunami crashing into the northeast coast in the country's worst post-war disaster. The wave easily overwhelmed the world's biggest sea defences and swallowed entire communities. The confirmed corpse count rose to 10,151 on Saturday, with little hope seen for most of the 17,053 listed as missing. The tsunami knocked out the cooling systems for the six reactors of the Fukushima plant, leading to suspected partial meltdowns in three of them. Hydrogen kabooms and fires have also destroyed the facility. High-voltage electric cables have since been linked up to the reactors again and power has been partially restored in two reactor control rooms. |
| Posted by:Fred |
| #19 rammer We don't need yucca mountain. That is Jimmy Carter's idiocy. We should be reprocessing the spent fuel. Two reactors and a reprocessing facility at each nuclear location. Once the initial fuel is delivered to the site, it never leaves, it is reprocessed. Any additional fuel sent to the site after the initial load is U238 only, never need to ship any more U235. Google "smarter use of nuclear waste" in Scientific American. You don't need to wait "a century or two" to reprocess the fuel, it can be done immediately. The French do it, India does it, Russia does it, Japan has just started. The problem is that when that plant was designed, the idea of plate techtonics and continental drift were not yet accepted science. They had no idea they were building that plant right next to a subduction fault because there was no such thing as a subduction fault or a megathrust quake at the time. In the context of 2011 knowledge, yeah, dumb idea. In the context of 1960's knowledge, perfectly fine. In fact, all four of those older reactors were ALREADY slated for decommissioning. Unit 1 was to be decommissioned this month. The others (1-4) at 2 year intervals. Units 5 through 8 (7 and 8 currently under construction) were higher up (units 5 and 6 undamaged by tsunami). Had this quake waited 10 years, we wouldn't be having this problem. |
| Posted by: crosspatch 2011-03-27 23:50 |
| #18 Now why the heck would I want to go to Tokyo? I can get all the Japanese pron I want on cable! |
| Posted by: Godzilla 2011-03-27 23:02 |
| #17 Yuh oh, RADIATION SEA SPIKES = usuually means GODZILLA IS COMING! |
| Posted by: JosephMendiola 2011-03-27 20:32 |
| #16 crosspatch, let me be more clear, while the designers of Fukushima may have thought they were designing for a 500 year tsunami in the 60s, subsequent information available in the 90s (referenced above by #2) showed they had not. A large part of the design problem is in doing and updating the assessments of risk for the future. When the information is not available or is proven to be wrong, then changing the way we use these structures until they can be upgraded is an important but often overlooked approach. The 1993 tsunami could have been used as evidence at Fukushima to move the spent fuel somewhere else or to protect the backup systems. A similar problem has delayed the Yucca Mountain storage facility. We are asking for a 10000 year design, which is very hard to estimate. A better plan would be to ask for a 500 year design and plan to migrate everything into a subsequent facility in one or two centuries. This approach also makes sense with respect to the nuclear fuel cycle, since more than 95% of a used nuclear fuel rod is still good fuel. After a century or two, most of the dangerous radioactive daughter atoms will have decayed, and the fuel rod can be safely reprocessed and reused prior to re-storage. The important point is that selecting the design lifetime for a structure has real implications about not just the cost to build, use and retrofit, but also the seriousness of responding to information from new research that should update the initial estimates about design risks. |
| Posted by: rammer 2011-03-27 20:17 |
| #15 *happy sigh* I purely love what happens when good questions are asked at Rantburg! |
| Posted by: trailing wife 2011-03-27 19:07 |
| #14 Fukushima Dai-ichi was designed for a 7 meter tsunami which was what they considered was the highest ever recorded there. A tsunami over 20 feet is still something quite spectacular. They ended up with a tsunami around twice that. |
| Posted by: crosspatch 2011-03-27 17:56 |
| #13 One would be wise to design to 500 year standards if the if the thing was supposed to last 500 years, or if the potential impact of failure to do so would have impacts over 500 years. Thus a supermarket lasting a few decades, which could be rebuilt in a few months, should not be built for much beyond normal building codes. A cathedral intended to last for centuries, which takes a century to build, should be built at or above the 500 year maximum event. A nuclear waste storage facility, i.e. a nuclear reactor, when it fails will contaminate large regions around it with isotopes that take centuries to decay. So even though the reactor was designed for only 50 years of use, the stuff inside it is much more problematic, and requires taking the long view in the design. That was done at Fukushima, for rain, weather and earthquakes, but not tsunamis. Oops, lesson learned. |
| Posted by: rammer 2011-03-27 17:21 |
| #12 to expand: Partially depends on what materials. Homes are typically wood, which, barring termites, water damage, etc. last 50-100 years with no problems. Commercial buildings are typically concrete/steel/masonry. They outlast the elements, but not necessarily the economic interests: "outdated, non-expandable, 'doesn't fit our needs'", etc. It makes no sense to design to a 9.0 Quake when the surrounding infrastructure would be devastated. You design for "survivability during an event", not "no damage" |
| Posted by: Frank G 2011-03-27 16:35 |
| #11 "is it reasonable to require building to once-in-500-years standards?" Only if you expect the building to last 500 years. If you expect it to exist for 50 years, maybe you design for a 100-year event. |
| Posted by: crosspatch 2011-03-27 16:25 |
| #10 100-year means a probability of one event in a 100-year period, or a 1% chance in any given year. These calculated probabilities are all about predicting the future, a hazardous thing to attempt, and are built on models which cannot be tested ahead of time. The model of tsunami prediction used to safeguard Fukushima Daiichi was grossly in error. |
| Posted by: Anguper Hupomosing9418 2011-03-27 15:33 |
| #9 Re#3: I wonder if the Japanese will learn more from 3/11 than the US did from 9/11. I wonder if the Japanese will USE what they have and will learn from 3/11 BETTER than the US did from 9/11. |
| Posted by: USN,Ret 2011-03-27 11:23 |
| #8 #6: Question for our civil engineers: is it reasonable to require building to once-in-500-years standards? no |
| Posted by: Frank G 2011-03-27 11:09 |
| #7 TW - A central US nuke was designed for PMP - Probable Maximum Precipitation. Which I recall (from 30 years ago) was not much more than the 500 year event, which is not a lot more than the 100 year event. The pipes were not big enough to contain that storm, but we had to make sure the main access road did not flood. Not far from there, in the 1970's, a part of Kansas City had a 100-year event on Friday and a 100 year event on Saturday - the next day. 100-year means a probability of one event in a 100-year period, or a 1% chance in any given year. That also means a 37% chance it will not occur in 100 years, or a 13% chance it will not hit in 200 years. So you pay your money and you take your chances! |
| Posted by: Bobby 2011-03-27 11:06 |
| #6 Question for our civil engineers: is it reasonable to require building to once-in-500-years standards? It starting to sound like there should be no residences or key industries built except on the inland side of mountain ridges, just in case. |
| Posted by: trailing wife 2011-03-27 08:32 |
| #5 The Northern coast of Western Australia would be subject to impacts from Indonesia such as the Lake Toba eruption and the eruption of Krakatau in 535 which were larger than anything we have seen in modern history. |
| Posted by: crosspatch 2011-03-27 03:13 |
| #4 Western Australia also has these deposits that indicate tsunamis that swept inland for several kilometers. The thinking is they are too big to be caused by earthquakes and likely result from volcanic events - eruptions or collapses -, meteorite ocean impacts, or continental shelf sediment collapses. |
| Posted by: phil_b 2011-03-27 02:26 |
| #3 I wonder if the Japanese will learn more from 3/11 than the US did from 9/11. |
| Posted by: Anguper Hupomosing9418 2011-03-27 02:00 |
| #2 NY Times: Two independent draft research papers by leading tsunami experts — Eric Geist of the United States Geological Survey and Costas Synolakis, a professor of civil engineering at the University of Southern California — indicate that earthquakes of a magnitude down to about 7.5 can create tsunamis large enough to go over the 13-foot bluff protecting the Fukushima plant. Mr. Synolakis called Japan’s underestimation of the tsunami risk a “cascade of stupid errors that led to the disaster” and said that relevant data was virtually impossible to overlook by anyone in the field. Perhaps the saddest observation by scientists outside Japan is that the inadequacy of anti-tsunami safeguards at Fukushima should have been recognized. In 1993 a magnitude 7.8 quake produced tsunamis with heights greater than 30 feet off Japan’s western coast. 1100 year old Japanese records indicate a tsunami swept a mile inland just north of the distress nuclear plant. Geologic investigations in Japan have shown deep deposits of ocean sand miles inland from the shoreline, implying destruction cause by huge tsunamis in prehistoric times,occurring about every 500 years over the last 2-7,000 years. |
| Posted by: Anguper Hupomosing9418 2011-03-27 01:58 |
| #1 Gonna be tough to put a happy face on this... SENDAI, Japan – The radioactivity of water in Unit 2 of the Fukushima Dai-ichi plant in northeastern Japan has tested 10 million times higher than normal, the plant's operator said Sunday. Chief Cabinet Secretary Yukio Edano, speaking Sunday on TV talk shows, said the radioactive water is "almost certainly" seeping from a reactor core. |
| Posted by: tu3031 2011-03-27 01:54 |