FEPC has released another update. Not great news. The cores are all at least partially exposed. The water temperature in the spent fuel pond is 183 degrees Fahrenheit — close to boiling.
The fact sheet contains a small amount of editorializing, comparing the one hour dose at the main gate to a chest CT scan. Keep in mind that a chest CT scan results in a much higher dose than a traditional X-Ray and there is some controversy about the societal risk from unnecessary CT scans. And no one thinks it would be a good idea to get a CAT Scan every hour.
Update to Information Sheet Regarding the Tohoku Earthquake
The Federation of Electric Power Companies of Japan (FEPC) Washington D.C. Office
As of 10:15AM (EST), March 16, 2011
- Radiation Levels
- At 6:40AM (JST) on March 16, a radiation level of 400 milli sievert per hour was recorded outside the west side of the secondary containment building of the Unit 3 reactor at Fukushima Daiichi Nuclear Power Station.
- At 6:40AM on March 16, a radiation level of 100 milli sievert per hour was recorded outside the west side of the secondary containment building of the Unit 4 reactor at Fukushima Daiichi Nuclear Power Station.
- At 8:47AM on March 16, a radiation level of 150 milli sievert per hour was recorded outside the secondary containment building of Unit 2 reactor of Fukushima Daiichi Nuclear Power Station.
- At 8:47AM on March 16, a radiation level of 300 milli sievert per hour was recorded between the exteriors of the secondary containment buildings of Unit 2 reactor and Unit 3 reactor of Fukushima Daiichi Nuclear Power Station.
- At 8:47AM on March 16, a radiation level of 400 milli sievert per hour was recorded outside the secondary containment building of Unit 3 reactor of Fukushima Daiichi Nuclear Power Station.
- At 8:47AM on March 16, radiation level of 100 milli sievert per hour was recorded outside the secondary containment building of Unit 4 reactor of Fukushima Daiichi Nuclear Power Station.
- At 10:40AM on March 16, a radiation level of 10 milli sievert per hour was recorded at the main gate of the Fukushima Daiichi Nuclear Power Station.
- At 4:10PM on March 16, a radiation level of 1530 micro sievert per hour was recorded at the main gate of the Fukushima Daiichi Nuclear Power Station.
- For comparison, a human receives 2400 micro sievert per year from natural radiation in the form of sunlight, radon, and other sources. One chest CT scan generates 6900 micro sievert per scan.
- Fukushima Daiichi Unit 1 reactor
- At 6:55AM on March 16, the pressure inside the reactor core was measured at 0.17 MPa. The water level inside the reactor core was measured at 1.8 meters below the top of the fuel rods.
- Fukushima Daiichi Unit 2 reactor
- At 6:55 AM on March 16, the pressure inside the reactor core was measured at 0.043 MPa. The water level inside the reactor core was measured at 1.4 meters below the top of the fuel rods.
- Fukushima Daiichi Unit 3 reactor
- At 8:37AM on March 16, white smoke was observed emanating from the vicinity of the secondary containment building.
- At 9:55AM on March 16, the pressure inside the reactor core was measured at 0.088 MPa. The water level inside the reactor core was measured at 1.9 meters below the top of the fuel rods.
- At 11:32AM on March 16, it was determined that the possibility of significant damage to the primary containment vessel was low.
- Fukushima Daiichi Unit 4 reactor
- At 4:08 on March 15, the temperature of the spent fuel pool was measured at 183 degrees Fahrenheit.
- At 5:45AM on March 16, a fire occurred in the vicinity of the third floor of the secondary containment building.
- At 7:26AM on March 16, no flames or smoke was observed and thus it was concluded that the fire extinguished on its own accord.
- Rokkasho Reprocessing Plant and Accompanying Facilities
- From 12:00PM on March 15, power generation from the commercial electricity grid was restored for all facilities. It was confirmed that no fire, damage to equipment, injuries to personnel occurred. Radiation levels were measured at a normal level of safety.
Something’s brewin’ in the research and fuel processing facilities, hopefully nothing too serious (like at the Tokai NPP, where they reported the failure of one recirculation pump over the weekend, with no actual problems in core cooling):
Since those formal annoucements (to NISA) of heightened preparedness are almost two days old with no mentions of them in the wider news, these are probably only of technical interest.
I get the feeling they’re cherry-picking the radiation readings they report. They’re also conveniently not mentioning much about the spent fuel pools for units 1, 2, 3, 5, and 6
A German reactor safety organization has been attempting to plot and correlate the publicly released radiation measurements against timed reports of various explosions and venting events.
Comparisons between earlier days and the situation today is being hindered by unability to get measurements from the closest measurement posts (or locations for the mobile measurement vehicle to stop at), because the dose rates are too high to keep up continued manual dose rate counting.
If the graph is accurate, it does show a very disturbing trend indeed.
The figures are approximates because at 400 mSv your approaching deterministic effects on the human body. You can’t hang around and get an accurate reading in those conditions.
The Japanese are also graphing emissions at many locations near the site. You may want to take a look at this picture I grabbed.
[IMG]http://i55.tinypic.com/e6c5fm.jpg[/IMG]
thanks for the site Red_Blue. GRS also say…
“Units 5 and 6
In Block 5 it is reported by the IAEA that on 03.15.2011 by 21 clock (13.00 GMT), that the water level in the spent fuel pool had dropped to 201 cm above the fuel elements. This was a drop of 40 cm from 16.00 (08.00 GMT). The plan is to use an available diesel generator for block 6 to supply water.”
I wonder if the fuel here is spent or UNspent due to inspections?
Sorry Eve,
are you sure that IAEA isn’t talkin about the water level in the reactor n.5?
Yes reactor 5, as stated.
TEPCO also recently stated for reactor 4 that “The possibility of recriticality is not zero”. There is the possibility that the fuel offload may reach criticality again.
(in the “spent” fuel pond)
How much of the fuel is even “spent” in the pond. To date, we have no date about when it was loaded. These are undoubtably esoteric questions in the unfolding crisis but they expose information gaps that might have (past tense) influenced earlier decisions.
Only the logs will show. Perhaps they were ready to reload, or they had just finished offloading? This data should be made widely available and to the IAEA. What is the practice for reactors during inspection across Japan?
> A German reactor safety organization has been attempting to plot and correlate the publicly released radiation measurements against timed reports of various explosions and venting events.
Looking at the high spike around 0900 yesterday (I think, it’s hard to read the times), subsequent rapid drop-off and exponential-looking tail, I’m reminded of post-scram core heat power curves. I.e., I’m wondering if the spike wasn’t caused by fission products from a minor criticality event. If not, what would give the spike-and-decay shape shown?
Boil off from the bottom of the pool?
“One chest CT scan generates 6900 micro sievert per scan.”
I notice they don’t put that one in milli sievert. So the radiation coming out of Unit 3–400 milli sievert per hour–would be 400,000 micro sievert, right?
@Scott
Yeah, 400,000 uSv. I wonder how many reporters will notice the difference?
Only druggies understand the metric system.
Yeah, you’re right.
Its not greek to me. Its just 3 orders of magnitude.
And if measured in mSv not uSv you’ve got problems.
How is this going to effect the Pacific Northwest, specifically Southern Oregon? I live in Ashland Oregon and wondering if its wise to consider leaving the area, at least temporarily.
If doserates are measured in milli Sv not micro you have problems.
Updated local rad feeds every 10 min, with winds:
http://www.houshasen-pref-ibaraki.jp/present/result01.html
One town was over 2000 nGy/hr yesterday. Interesting to monitor.
Jeffrey, Thanks for continuing to post these updates. Don’t know if you have seen Japan Atomic Industrial Forum’s website as well but they are compiling information on the situation at Fukushima in visually accessible tables. The files are in PDF format, titled “reactor status update,” and located at http://www.jaif.or.jp/english/index.php
How long would it take for the Unit 4 cooling pond to boil and dry? Well, we know that the earthquake hit on Friday at 14:46 JST, and we can assume that the water was at a nominal 42 degrees C at that point. By 4am on Monday (61 hours later) the temperature was 84 degrees C. Plugging in the specific heat of water, etc, the ratio of radioactive are heating per unit time (in Watts) to the pond mass (in kg) is 0.8J/(kg*s), or 0.8W of heating per kg of water in the pond. We can calculate that the pond would reach 100 degrees C at around 3am on Tuesday. All the water in the pond would have boiled away (due to latent heat of vaporization) 87 minutes later, at around 4:27am on Tuesday. Soon after this, the Zirconium-encased Uranium rods would start to oxidize and release hydrogen. Well, at around 6:15 a.m. there was an explosion, consistent with this prediction. After oxidation of the Zirconium, the only thing preventing melting of the Uranium and waste products in the spent fuel rods is the heat capacity of the Uranium dioxide. That’s not very much, so I predict that some of the fuel rods (definitely the fresh ones from reactor 4) have now melted onto the floor of the coolant pond. These globs of molten uranium dioxide will then start burning the concrete floor and vaporizing, releasing radiation. I believe that this is the cause of the radiation being detected. As soon as they figure out a way to pump water into the Unit 4 cooling pond, the globules of molten uranium dioxide will cool and the radiation will subside. However, I suspect that radiation levels around the Unit 4 cooling pond will probably be enough to kill someone. So someone is going to have to sacrifice themselves and put a firehose into the cooling pond. Where’s Bruce Willis?
Two observations on today’s press conference:
1. IAEA says it isn’t getting data on radionuclide composition
2. IAEA safety says it doesn’t know when unit’s 1 & 2 were last loaded with fresh fuel.
WTF? Safeguards clearly has fuel load data. Hard to believe there’s no emergency protocol for cross departmental information sharing. Hard to believe IAEA has no radionuclide data 5 days into the event.
Lots at stake in unit-3. First MOX melt in history. Billions on the line.
Also hard to believe that IAEA.org was out for several hours due to an 11X increase in traffic.
Why not use new generation military robots for taking the radiation measurements? I’m sure the US have suitable ones!
I have been following the Reuters blog where the same question has been posed by a number of people. The answer is always the same: the robots wouldn’t be able to “survive” the radiation levels that have been reported so far…I cannot vouch for the veracity of this answer though. That said, this strategy was apparently attempted in Chernobyl and did not prove useful.
Do we know if the military still builds things for the NBC environment anymore?
It is sobering to think that 25 years after Chernobyl we are still using ‘bio-robots’. If we are going to continue using fission perhaps we should have some agency develop and deploy various kinds of robots useful for firefighting and cleanup in the nuclear power plant environ. Use Chernobyl and Fukushima Daiichi (…yeah … THE ONE) to generate the specifications for operations. This kind of equipment would be handy for the folks who are supposed to be preparing for atomic terrorism as well.
Andrew, even if the robots were not built for NBC environments and they will stop working after a few days it’s ok, they are expandable. You could probably recall them on first sign of malfunctioning so they wouldn’t clutter the reactor immediate surrounding. You can’t ask the reactor workforce to sacrifice themselves and their expertise is too valuable to lose. The main problem I see is training time but maybe having teams of an American operator, Japanese expert and a translator could start working right away.
I read some years ago about a small company in Upstate New York that made robots specifically designed to inspect the interiors of nuclear reactors, where people can’t go.
A while back NHK world had a documentary about/hour long advertisement for japanese nuclear decommissioning skills. Its showed several (2, 3??) special purpose robots including one for a specific cutting operation (cutting open the pressure vessel from the inside????).
Some people in Japan know people who build high radiation robots. I have not seen general purpose robots that can look around and/or drag fire hoses though.
I would not knock non radiation resistant robots. Wouldn`t it be mostly about digital electronics sensitive to radiation flipping a single bit? A plain bomb disposal robot might just last long enough to drag itself and small firehose into the fuel pools. (though dragging cables and hoses trough mud is really heavy) I have an even simpler (largely electro-mechanical less sensitive?) over-sized amphibious off road RC car that could drag a garden hose.
With so many RC toys available at least one should be able to carry cameras/sensors to a point.
From the sound of things its worth trying improvisation for fuel ponds, at least you would end up with a camera inside the building, maybe some measurement equipment.
I have been burned on this blog before when I asked whether Iran wouldn`t need radiation resistant CPU`s for missiles that reach high enough. The answer it turns out is no, missiles, unlike satellites, don’t spend enough time up there.
Helicopters and helicopter crews used to hanging powerlines should also be able to accurately hoist a hose into a specific location provide the roof is gone, those water drops dont look particularly accurate, but its a lot of water.
How long would it take for the Unit 4 cooling pond to boil and dry? Well, we know that the earthquake hit on Friday at 14:46 JST, and we can assume that the water was at a nominal 42 degrees C at that point. By 4am on Monday (61 hours later) the temperature was 84 degrees C. Plugging in the specific heat of water, etc, the ratio of radioactive are heating per unit time (in Watts) to the pond mass (in kg) is 0.8J/(kg*s), or 0.8W of heating per kg of water in the pond. We can calculate that the pond would reach 100 degrees C at around 3am on Tuesday and start boiling. Well, at around 6:15 a.m. there was an explosion, consistent with this prediction. All the water in the pond would have boiled away (due to latent heat of vaporization) 784 hours later. So sometime next month. Unless of course there’s a crack in the spent fuel pool, which is leaking water… that would be bad!
CTBTO monitoring network first measure radioactivity on Japan
The IAEA probably not, but CTBTO have radionuclide data because at this link they are providing some:
http://www.zamg.ac.at/aktuell/index.php?seite=1&artikel=ZAMG_2011-03-16GMT12:35
The CTBTO station in Gunma, Japan (JPP38, 139 °, O, 36.3 ° N), is from Saturday to Sunday, 13.3.2011 12.3.2011 06:55 Z 06:55 Z radionuclides detected the following:
Nuclide
Concentration μBq / m³
Cesium-134
15
Barium 136m
4.8
Cesium 136
4.9
Cesium 137
12
Iodine 131
83
Iodine 132
82
Iodine 133
44
Tellurium 132
110
Can someone comment on the significance of the reactor pressure being below 1 atmosphere in reactors 2 and 3?
Ed Lyman’s senate testimony:
http://www.ucsusa.org/assets/documents/nuclear_power/lyman-senate-statement-japan-crisis.pdf
excerpt:
1. At least two spent fuel pools at the Fukushima plant have caught fire and are releasing
radiation into the atmosphere. These pools are on the upper floor of these Mark I boiling-water
reactors and are now open to the air following explosions that breached the buildings around
them. The United States has 31 boiling-water reactors with similarly situated spent fuel pools
that are far more densely packed than those at Fukushima and hence could pose far higher risks
if damaged. The United States should act quickly to remove spent fuel from these pools and
place them in dry storage casks to reduce the heat load and radioactive inventories of the pools.
2. The Fukushima accident was precipitated by an earthquake and tsunami, but the direct cause
appears to have been a loss of both off-site and on-site power supplies, a situation known as a
station blackout. There are many other types of initiating events that could cause such a
situation, including terrorist attacks. The NRC requires U.S. plants to have the capability to
cope with a station blackout for no more than four to eight hours. We need to re-evaluate the
adequacy of these requirements and the effectiveness of their implementation.
3. Although the Japanese are engaged in truly heroic efforts to mitigate the worst effects of this
accident and reduce radioactive releases that could harm the public, these efforts have only
been partially effective, are already resulting in life-threatening conditions for the workers on
site, and are likely to ultimately fail. U.S. nuclear plants have severe accident management
plans, but these plans are not required by regulations and do not have to be evaluated by the
NRC and tested for their effectiveness. In the case of aircraft attack on a nuclear plant, the
NRC does require plants to have plans to cope with the loss of large areas of the plant due to
explosion and fire. These plans will have to be re-evaluated in light of Fukushima to judge
whether they can be realistically carried out. In the meantime, the NRC should place a far
greater emphasis on preventing accidents and terrorist attacks rather than trying to control them
afterward.
4. Elevated levels of radiation have already been detected more than one hundred miles from the
release site. While these levels remain low, if the accident continues to worsen then they could
increase dramatically. If there was a reactor accident in the United States, the emergency
preparedness measures that would directly protect the public, including evacuation planning
and potassium iodide distribution, are limited to a 10-mile radius. Whether this distance
should be increased will need to be reevaluated, as will the workability of emergency plans in
the context of natural disasters or terrorist attacks.
There are many other areas where we believe the NRC has allowed safety margins to decrease too far.
That testimony does not start well, as the fuel in the two pools has not caught fire (at least yet). If they had, the radiation level nearby would be in totally different readings. What has burned has been apparently pumps and other equipment next to the spent fuel pool.
The bad news is that either the fires increased the boil-off speed considerably or the fires or explosions have caused leaks in the pools. The expected time for fuel pool drying without leaks would be about eight days and it happened in five.
Spruce, does your “about eight days” take into account the freshness of the SNF in the Units 4 to 6 ponds? IAEA reported Unit 4 was shutdown 30 November 2010 and defuelled to pond. I’d very much like to see a reasoned argument, with numbers, on evaporation rates and consequences assuming no refilling.
Clever design by GE: in case of emergency the plant generates hydrogen to blow the top off of the building to make it easier for helicopters to dump water in the spent fuel pool! Good engineering you got there.
Team America screwin’ up my whole pran!
FSB: Lay off the oatmeal. The hot air coming from your direction is more poisonous than what’s inside any reactor in Fukushima.
Oatmeal no good for me. I need boric acid!
Given the present uncertainty of radiation measurements I rather think at this stage someone at IAEA/FEPC should look up the Australian outfit described here http://www.shephard.co.uk/news/4521/ who seem to be possibly the only one with a civilian “perch and stare” UAV sensor platform readily available.
The IAEA can confirm the following information regarding the temperatures of the spent nuclear fuel pools at Units 4, 5 and 6 at Fukushima Daiichi nuclear power plant:
Unit 4
14 March, 10:08 UTC: 84 ˚C
15 March, 10:00 UTC: 84 ˚C
16 March, 05:00 UTC: no data
Unit 5
14 March, 10:08 UTC: 59.7 ˚C
15 March, 10:00 UTC: 60.4 ˚C
16 March, 05:00 UTC: 62.7 ˚C
Unit 6
14 March, 10:08 UTC: 58.0 ˚C
15 March, 10:00 UTC: 58.5 ˚C
16 March, 05:00 UTC: 60.0 ˚C
In the lab we use beads/balls that float on boiling water baths to prevent boil off. These are very effective in reducing evaporation. It is a pity a emergency system like this, which could flood the top of the pool, was not thought about. A system could be composed of borosilicate material. One problem could be H2 buildup though.
BTW I don’t know how the expect to quickly disolve the 52 tons of boron they acquired
Reactor halls 5 and 6 are being prepared for ventilation to prevent a hydrogen explosion.
Why they don’t use (and sacrifice) a big fireboat? The water flow will be huge and continuos. Can a fire monitor can reach for sure 200 m, maybe if modified even more.
A big boat can be commanded by the sheltered engine room.
A water reach of 300m could be sufficient.
> A water reach of 300m could be sufficient.
250 m should do it, if the boat could get into the basin in front of the reactors.
The plant is at 37.422 N, 141.033 E for Google Earth enthusiasts who’d like to do their own IA work.
Another tsunami could do it also, but perhaps I should not chew the bad end.
FSB: Good on you. I think we all need more boron in our lives, as well as iodine and moon suits.
Interesting how folks with an axe to grind for their own purposes jump on something like this, without understanding it as the same result of human weakness as, for example, Katrina & BP in LA, San Bruno in CA., or any of the other man-created disasters we’re oh so “concerned” about after they happen.
TEPCO & GE are at fault, as known for decades. Japanese regulators are at fault, and we’re all at fault for voting and thinking lazily. We want juice to run our Tweets, but we don’t want to read more than 144 characters to learn somethinbg about reality. Maybe folks need to listen to wise short folks more…
http://readersupportednews.org/opinion2/277-75/5298-safety-on-the-cheap
Or, think more about whom to vote for. Or, take some email time to write a letter to a rep or PUC, so folks counting on our laziness get a little nervous about letting a utility build unsafe gas lines, or letting the US Corps of Engineers ignore decades of warnings about New Orleans’ levies, yadda, yadda, yadda.
As Walt Kelly wrote for Pogo, decades ago: “I’ve seen the enemy and he is us”. Today, we might well add: “And OMG us is oh so self involved”.