Crack In Fukushima Structure May Be Leaking Radiation 280
SillySnake writes with this excerpt from Reuters: "Tokyo Electric Power Co (TEPCO) said it had found a crack in the pit at its No.2 reactor in Fukushima, generating readings 1,000 millisieverts of radiation per hour in the air inside the pit. 'With radiation levels rising in the seawater near the plant, we have been trying to confirm the reason why, and in that context, this could be one source,' said Hidehiko Nishiyama, deputy head of the Nuclear and Industrial Safety Agency (NISA), said on Saturday."
Also of interest: Cryptome is featuring high-res photos of the reactor site, taken by UAV.
Original report from TEPCO (Score:5, Informative)
here:
http://www.tepco.co.jp/en/press/corp-com/release/11040307-e.html [tepco.co.jp]
-Today at around 9:30 am, we detected water containing radiation dose overc
1,000 mSv/h in the pit* where supply cables are stored near the intake
channel of Unit 2. Furthermore, there was a crack about 20 cm on the
concrete lateral of the pit, from where the water in the pit was out
flowing.(We already informed.) During the same day, we injected fresh
concrete to the pit, but we could not observe a reduction in the amount
of water spilling from the pit to the sea.
Therefore, we considered that a new method of stopping the water and
determined to use the polymer. Necessary equipment and experts of water
shutoff will be dispatched to the site and after checking the condition,
we're doing continuous work to stop water by injecting polymer(April 3rd).
-Monitoring posts of No. 1 ?No.8 set up near the boundary of power station
area have been restored. We will periodically monitor the data and
announce the results of monitoring.
This crack maybe explains why the levels of I-131 had not dropped at the same rate than in the previous days in the readings of I-131 and Cs-137 published by MEXT in their readings of radiation and contamination of water by prefecture page. [mext.go.jp] In most prefectures they have dropped to levels that are not detectable but in a few the levels of Cs-137 have increased.
Re:"May be" "Possibly" "Calm down" "Sleep" (Score:5, Informative)
1000 milisieverts that's twenty times as much as the one-year limit for Radiation workers [xkcd.com], meaning spending some time there would make it impossible to survive (8 Sv).
Re:"May be" "Possibly" "Calm down" "Sleep" (Score:5, Informative)
Crack In Fukushima Structure May Be Leaking Radiation
I skimmed TFA and it seems the "may" was introduced by /. editors and not the evil "mainstream media". There is a leak and it is radioactive water that it is leaking. No maybe. Actually they already planned how to fix it [nhk.or.jp] , tried to do so and failed at it [nhk.or.jp].
Re:Incompetence (Score:5, Informative)
The 'crack' mentioned in this case is not in the reactor containment itself as the summary and article imply, but in a water storage pool next to the sea, with the crack being between the pool and the sea.
Not that lessons can't be learnt from this: gravity-feed coolant reservoirs would be a good idea, as well as separate backups for the storage pools and cores, but it's far from "getting steadily worse".
IAEA Incident page [iaea.org]
MIT NSE hub [mitnse.com]
WNN [world-nuclear-news.org]
Re:Incompetence (Score:5, Informative)
This reactor was hit by one of the largest earthquakes ever recorded, followed up by a 30 foot tidal wave. Had this happened to any other major source of power (coal, natural gas, hydroelectric) the death toll would have been in the hundreds... maybe in even the tens of thousands if it had been a hydroelectric damn.
Please, do some reading so you have some idea of what you're comparing this to:
http://en.wikipedia.org/wiki/Chernobyl_disaster_effects
Chernobyl was a horrific even, orders of magnitude more devastating that what's happening in Japan right now. Just the initial released was equal to a 50 kiloton atomic bomb going off.
Re:The cost of nuclear (Score:4, Informative)
Re:Millie bloody who? (Score:3, Informative)
I don't understand. Can someone translate that into old-fashioned units like luminous watches per hockey game?
Various sources[1,2] indicate a range of 1-100 mrem/hr for a radium watch face, with about 20 mrem/hr looking like a plausible average. 1 mrem == .01 mSv[3], so 1000 mSv is about 5000 watch faces/hr. Apparently a standard ice hockey game is 60 minutes[4], so:
1000 mSv/hr == 5000 radium watch faces/hockey game
[1] http://trusted-forwarder.org/elgin/help/luminous_dials.html [trusted-forwarder.org]
[2] http://www.nuenergy.org/alt/radium2.htm [nuenergy.org]
[3] http://en.wikipedia.org/wiki/Sievert [wikipedia.org]
[4] http://en.wikipedia.org/wiki/National_Hockey_League#Game [wikipedia.org]
Re:"May be" "Possibly" "Calm down" "Sleep" (Score:4, Informative)
You're mixing up irradiation and contamination. Contamination means that you carry a radiation source in or on your body (ingested particles, dust on the skin, etc.). Irradiation means radiation is affecting your body, no matter where the source is. Contamination causes irradiation even when you leave the site (until you're decontaminated, if possible). Internal contamination is particularly bad because you can usually not get away from the radiation source anymore. That doesn't mean that "just" being irradiated isn't dangerous.
If you're close to a radiation source, whether you're contaminated or just physically close to a source that is not on or in your body, the radiation penetrates your body and damages the cells. Alpha radiation (helium nuclei) only interacts with the surface and is easily shielded. Beta radiation (electrons and positrons) penetrates a little deeper but can still be shielded. Gamma radiation (electromagnetic waves, beyond x-rays) can not be shielded sufficiently by a radiation suit and penetrates the whole body.
Re:Incompetence (Score:4, Informative)
A dam used for irrigation and drinking water [wikipedia.org] (much like any hydroelectric dam anywhere in the world) in the hills above Fukushima town failed during the earthquake. The resulting flood killed at least four people and a bunch of others in houses downstream are missing, presumed drowned.
Several dams in the area are known to have sustained damage but many others have not yet been properly inspected.
Fixing this leak solves nothing! (Score:5, Informative)
NOTE: This post is mostly recycled from a previous post at the bottom of a thread under the previous Fukushima story. The thread started with a post I made warning that most of the radioactivity leaking from Fukushima was moving downward into the ground and ocean, not upward into the air.
Filling the crack and fixing this leak won't reduce the amount of radioactive material spewing from reactor #2 into the environment. This pit and the concrete with the crack in it were never intended to be part of the containment system. If they succeed, then the HRW (highly radioactive water) will either (a) find another way into the sea, or (b) further contaminant the groundwater, or (c) flood the ground and then do (a) or (b). Depending on the total amount of radioactivity released, it *might* actually be better to pour this HRW into the ocean where it will be diluted down to safe levels.
The term "containment" has a fairly precise technical meaning (BTW: I've got a Ph.D. in nuclear physics but not nuclear engineering). These reactors are basically a bottle in a bottle. The inner bottle is the pressure vessel and it is used to maintain pressure for the creation of steam and electricity. The outer bottle is 10cm or 20cm thick stainless steel. It is called the containment vessel. Its sole purpose in life is to contain all the radioactivity in the event the fuel rods melt down. Normally almost all the radioactivity is contained in the zirconium clad fuel rods. That is why there can be HRW 100,000x higher than the water found in a functioning reactor. Almost all of the radioactivity in a functioning reactor of this type is contained in the fuel rods. When the fuel rods melt down, high levels of radioactive materials contaminate the water making it highly radioactive.
Up until last week, the word "containment" had the simple and obvious meaning of radioactive materials staying inside the massive stainless steel containment vessel. I believe TEPCO forged a new meaning in order to downplay the significance of the HRW that was found in the turbine buildings. I will use the traditional technical definition, not the new one invented by TEPCO.
You see, the idea was that as long as the radioactivity was kept inside the containment vessel then you could safely operate the plant and move around in it. The environment was safe. The control room was safe. The turbine building was safe. Even the reactor building was safe (as long as you stayed out of the containment vessel and storage pool). Everything was safe. One of the difficulties caused by a loss of containment accident is that it becomes difficult and dangerous to work on the plant. That is why they need to pump out the turbine buildings before they work on restoring the cooling. If they hadn't lost containment (in the traditional sense) this would not have been a problem.
The pit, the tunnels, and even the turbine buildings were not designed to contain radioactivity. The buildings were designed, like most buildings, to keep the rain out, etc. For example, right after they had those scary hydrogen explosions that blew apart the reactor buildings, I was assuring people it was not a big deal because those buildings were never designed to contain radioactivity. TEPCO and the government were offering the same assurances.
When I heard about the HRW in the turbine buildings I stopped issuing reassurances and I started to be greatly concerned because it meant they had lost containment. I was hoping against hope that the HRW in the turbine buildings was a fluke and that it hadn't spread elsewhere. When I then then heard the tunnels outside the turbine buildings were flooded with HRW I knew this was a serious accident, much worse than Three-Mile Island. When I heard there were 18,000 tons of HRW outside of containment (that number has now been reduced to 13,000 tons) I knew this was a big fucking deal and I was surprised that the Western press were ignoring these developments even though they had been h
2nd set of photos on Cryptome.org (Score:3, Informative)
includes lots of ground and non-aerial photos.
Re:Fixing this leak solves nothing! (Score:5, Informative)
I disagree that a constant level of HRW in the basements indicates that the basements are water-tight. Remember that they are pouring literally thousands of tons of water on the reactors in order to cool them. If the water level is steady then all it means is that the inflow is equal to the outflow. It is possible that both are zero but none of the information I've seen indicates this is so. In fact, it would seem rather remarkable to me that the leak (or leaks) leading from the reactors to the turbine buildings fixed themselves although it is possible that the spraying patterns changed enough to direct the HRW elsewhere. I think they should put dye in the HRW they've found because that would help them determine the flow rate and also find out if this water is leaking into the ocean. They use dyes to measure ocean currents so they can be measured even after being highly diluted.
It is certainly not true that the HRW is being contained in the buildings. Shortly after HRW was discovered in the turbine buildings, it was also discovered in three tunnels outside the turbine buildings. For some reason, this fact wasn't widely reported in the Western media. The tunnels are U-shaped. They go down from the surface about 15 meters, run horizontally about 80 meters and then come up 15 meters to the surface again. For some strange reason they call these tunnels "trenches". The HRW level in tunnel #1 was reported to be 10 cm from the surface. It was 1 meter and 1.5 meters from the surface in tunnels #2 and #3. The radioactivity of the water in the tunnels matched that in their associated turbine buildings.
The threat of the HRW in the tunnels overflowing onto the ground was so severe that they *reduced* the amount of water they were spraying on the reactors. This caused the outside temperature of the containment vessel of at least one of the reactors to rise by 20C.
I reiterate, fixing the leak in the concrete in the pit to stop HRW from pouring directly into the ocean will do nothing to fix the leak in the containment system. The flooded tunnels prove there are tons of HRW that have already escaped containment even by TEPCO's ridiculous definition.
Western media were pretty much ignoring Fukushima when news of the flooded tunnels broke. Their attention had shifted to Libya. A day or two after the flooded tunnels were reported, the focus in Japan shifted to the minuscule amounts of plutonium found outside the buildings. Now the news in Japan is about the direct leak into the ocean and the efforts to pump the HRW out of the turbine buildings so they can get back to work on restoring the cooling systems. It's been days since I last heard anything about the tunnels. You know, maybe they are not planning to drain the flooded tunnels right away and are instead concentrating on the buildings. This might account for the drop in the estimated total weight of the HRW from 18,000 tons down to 13,000 tons.
Re:The cost of nuclear (Score:4, Informative)
The sad thing is that they have done it properly, you can only see Fukushima Daini and Onagawa NPS that survived without mayor problems the earthquake and tsunami. Hell, you can even point to Fukushima Daiichi units 5 and 6 as a proof that those installations were secure. The big question will be why units1 to 4 weren't upgraded to the safety levels of the other reactors.