Yahoo: “The CAPTCHA you entered did not match please try again”

Today I tried to report an advance fee scammer in Senegal, West Africa who had sent me a scam email using a Yahoo Mail account. I went to the Yahoo Spam Report form and submitted the mail headers and message text, only to get this error message:

The CAPTCHA you entered did not match please try again

Yes, that was the exact punctuation. The form I had submitted did not have any CAPTCHA test to pass. A quick Google search found others reporting the same problem. It looks like Yahoo broke its abuse report handling, which if they don’t fix it soon will both save them staff costs and make them more popular with scammers.

The 105,000 ton cleanup

On Friday, 17 Jun 2011 TEPCO started up the water cleanup plant built for it by Areva SA in France, initially using only two of the four processing lines. Its objective is to decontaminate an estimated 105,100 t of radioactive water to make it safe to use it for reactor cooling or for shipping it to a nuclear waste processing site. Each processing line is designed to handle 300 t of water per day. Within five hours the processing had to be halted, as radioactivity built up much more quickly inside the system than expected.

TEPCO is under tremendous time pressure. Another 500 t of cooling water are pumped into the reactors from the Sakashita dam about 8 km to the wets of the plant every day. After it has cooled what’s left of the reactor cores it has nowhere to go.

Based on numbers published by the company on June 3, there were already 16,200 t of water in unit 1, 24,600 t in unit 2, 28,100 t in unit 3, 22,900 t in unit 4 and 13,300 t in the central radiation waste treatment building, which had mostly pumped been pumped there for from unit 2. In each unit, the basement of the turbine hall accounts for about half the water, with about another quarter in the reactor building and the rest split between the unit’s adjacent radioactive waste treatment building and a underground trench.

Radiation levels near the accumulated water in the basements are as high as 1000 mSv/h. The current legal limit any emergency worker can be exposed to is 250 mSv in total, which they would get in 15 minutes. It’s not safe to work anywhere near this water. If enough accumulated radioactive water can not be decontaminated far enough to be able to reuse it for cooling then TEPCO needs to keep pumping fresh water while bringing online ever increasing storage capacities to prevent the radioactive water from flooding the plant and spilling into the Pacific ocean.

Between them the buildings hold about 142,000 Terabecquerels (TBq) of Cesium-134 (half life 2 years) and 141,000 TBq of Cesium-137 (half life 30 years). Unit 2 holds about half of the total, and almost all of the rest evenly split between unit 3 and the central radiation waste building. That leaves the water in the basements of unit 1 and unit 4, which taken together only contribute a little over 1 percent of the total radioactivity according to TEPCO data. Units 2 and 3 each not only contain 50-60% more water than unit 1, it also is on average about 30 times more radioactive than the unit 1 water, which in turn is 10 times more radioactive than the water in unit 4. The latter had been shut down for maintenance since late November last year and had no fuel in the core at the time of the accident.

Judging solely by the water in the basements, unit 2 was the source of roughly 3/4 of the radioactive release in Fukushima, with most of the rest coming from unit 3. Even though on photographs unit 2 looks the least damaged of the four blocks, internally it is assumed to be in the worst shape, as it suffered an explosion in its pressure suppression chamber (torus) and it may also be damaged elsewhere.

An even greater percentage of the contamination of land is linked to unit 2 versus unit 3 than indicated by their basement radioactivity levels: When unit 3 was being vented and subsequently suffered the worst hydrogen explosion of all four units, the wind was blowing from the west, carrying most of the released radioactivity out over the Pacific. When things went badly wrong at unit 2 however, the wind was blowing from the South-East, carrying huge amounts of contamination over land to Namie and Iitate in the North-West. This is where contamination levels as high as in the most polluted portions of the Chernobyl exclusion zone have been measured.

The nuclear soup in the reactor basements contains about 3 kg of Cs-134 and 44 kg of Cs-137. If the water decontamination system works, most of this will eventually end up in sludge and filter elements that will be stored as highly radioactive waste.

See also:

Fukushima surprises

On April 12, one month after the devastating earthquake and tsunami that took TEPCO by surprise, leading to the meltdown of three reactor cores in Fukushima 1, the Japanese government raised its accident rating for the event. It moved it from a level 5 on the INES scale to a level 7 (same as Chernobyl), based on the amount of radioactivity released by then. At the time the Nuclear and Industrial Safety Agency (NISA) estimated that 370,000 terabecquerels (TBq) had been released into the environment, while the Nuclear Safety Commission (NSC) calculated the release as 630,000 TBq, with all nuclides converted to an equivalent amount of I-131 for comparison purposes.

Yes, we were told, Fukushima technically now ranked on the same scale as Chernobyl, but it had released “only” 10% of the radioactivity of the worst nuclear accident in history. The total release from Chernobyl is estimated at 5,200,000 TBq.

Now NISA has revised its estimate for Fukushima. “NISA on Monday more than doubled its estimate of the radioactive material ejected into the air in the early days of the Fukushima nuclear crisis to 770,000 terabecquerels,” reports the Japan Times. Apparently, the revision was based on the realisation that unit 2 not only leaked through the ruptured suppression chamber as previously known, but also leaked radioactive substances through a damaged containment.

That containment, if you remember the early days of the accident, was going to be why Fukushima was not going to be “another Chernobyl”. Or so we were promised. Now we know it leaked in all three units and even if it had worked, it was so weak that it would have ruptured if some of its content wasn’t intentionally leaked (“vented”) anyway.

Hot water in unit 2

TEPCO has installed a heat exchanger in the spent fuel pool of unit 2, in the only building amongst units 1-4 that still has a roof on it. They were hoping this would allow them to start repairing other parts of the reactor as soon as possible. Their theory was that the high humidity (greater than 99%) in the building was caused by evaporation from hot water in the spent fuel pool under the roof, with the moisture getting trapped inside the building. They managed to bring down the pool temperature much more quickly than anticipated, but to their surprise the humidity didn’t budge much: Unit 2 is still as moist as a greenhouse. This high humidity prevents air filters from being used for bringing down radioactivity levels in the air inside the building before sending in repair crews.

The humidity is probably rising off hot water in the basement. The radioactive decay of what’s left of the reactor core currently still produces about 6 MW of heat inside the containment, which is conducted through the concrete, pipework and any water and steam leaks. 6 MW of heat is roughly the amount of heat that would be produced burning 600 liters of kerosene every hour.

Nobody is really sure where the cores are now. They could still mostly be inside the reactor pressure vessel, with only a small amount leaked into the containment. Or it could be mostly on the concrete floor of the containment. Nobody really knows for sure yet.

Assuming the cores in all three units have melted, the melted core (“corium”) probably has much lower heat output than it originally did, because some 70% of the decay heat in nuclear fuel are from the more volatile elements. Once the uranium oxide heats up high enough to liquify, the volatile elements trapped inside the uranium ceramics can boil off and escape. Later they condensate inside the walls of the pressure vessel or containment. There they mostly get dissolved in water when cooling gets reestablished. After that the lump of uranium and plutonium oxide will only give off some 30% of its original decay heat because so much of the radioactivity will now be elsewhere in the reactor pressure vessel, the containment or other locations.

No pressure in unit 1 RPV and they knew

TEPCO sent workers into unit 1 to install new manometers to measure pressure inside the reactor. Doing their work they were exposed to about 4 mSv each, more than an ordinary person would receive during a whole year, but their risk has enabled us to receive proper data about the reactor pressure in unit 1.

As it turned out, the reactor pressure vessel (RPV) of unit 1 is at atmospheric pressure, which suggests the RPV is connected to the containment (i.e. has holes) and the containment is connected to the outside too. For weeks TEPCO had been pumping nitrogen gas into the RPV to dilute any existing hydrogen, in order to guard against the risk of explosions. No evidence of this nitrogen can be found now, or at least no gas pressure from its pressence.

In parallel with the nitrogen injection, a pressure gage for unit 1 had been showing increasing pressures in the unit 1 RPV, climbing as high as 1,6 MPa (about 16 bar) over the last couple of weeks. However, even before TEPCO installed a new gage they knew that value was wrong, without them telling the public. How do we know that they knew? As member “elektrownik” noticed, the new gage that they had those workers install has an instrument range of only 0.0 to 0.3 MPa…

TEPCO makes space for a lot of water

The Daily Yomiuri has a picture of some of the water tanks that TEPCO is buying for Fukushima 1. It has ordered 200 tanks holding 100 t each and 170 tanks holding 120 t each, for a total of 40,000 t. Several of these will be brought in each night by truck.

At the roughly 500 t of water that TEPCO pumps in for cooling purposes per day the tanks would last for less than three months. From June 15 TEPCO is planning to recycle 1200 t of highly radioactive water per day, pumped from the reactor buildings. It wants to either reuse it for cooling or to send it to the reprocessing plant in Rokkasho village for final cleanup.

If the water treatment plant doesn’t work as expected, that would be one surprise that TEPCO could definitely do without. The tanks may be one form of insurance against that possibility.

Chernobyl in the basement

TEPCO has released radiation figures for the 2700 t of water in the basement of unit 1 of the Fukushima 1 nuclear power plant:

Tokyo Electric Power Co. <9501> said Monday that the amounts of radioactive materials in water at a reactor building of the Fukushima No. 1 nuclear power plant were about 10,000 times the normal levels for water inside a nuclear reactor.
The water, recently found in the basement of the No. 1 reactor building of the nuclear power plant, contained 30,000 becquerels of iodine-131 per cubic centimeter, 2.5 million becquerels of cesium-134 and 2.9 million becquerels of cesium-137.

(Jiji Press, 2011-05-30)

A total of 2700 t of water are estimated to be in the basement. That works out as 6.75E15 Bq = 6.75 PBq of Cs-134 and 7.83 PBq of Cs-137. For comparison, the total radioactive release from Chernobyl is estimated at 48 PBq of Cs-134 and 89 PBq of Cs-137. That means the water in the basement of unit 1 alone contains about one tenth of all the radioactivity released into the environment by the Chernobyl disaster. When the accident started, we were told that “Fukushima is no Chernobyl” because unlike the Soviet reactor its reactors had containments. Unfortunately, they didn’t work. All that radioactivity mentioned above is already outside of the containment, in a place that was never designed to be flooded with thousands of tons of radioactive water.

Units 2 and 3 are assumed to be in equally bad shape as unit 1, as both suffered a meltdown and neither of those units’ containments still hold any pressure. All three units have flooded basements. Water in a trench near unit 2 was measured at 2 million becquerels of cesium-137 per cubic centimeters on March 30, quite similar in contamination to the unit 1 basement.

When people first entered unit 1 again on May 13, the water level in the basement of unit was reported to be 4.2 m. Two weeks later it is 4.6 m and the storage tanks at the reactor site are almost full. Very soon something needs to happen about that water. To complicate things even more, June is the rainy season in Japan, when typhoons can dump huge amounts of water onto Japan.

The water treatment plant built by Areva is expected to start operating around the middle of this month. TEPCO quoted the cost of decontaminating water with this system at 210,000 yen per ton (about US$2600). It intends to decontaminate 250,000 tons of water by the middle of January 2012, for a total cost of 53.1 billion yen (about US$650 million).

Currently 5 cubic meters per hour (m3/h) are being pumped into unit 1 for cooling, 4.9 m3/h into unit 2 and 12.5 m3/h into unit 3 (which is still overheating). That’s about 550 tons of water per day, which is assumed to leak into the basements of the three reactors, loaded with dissolved radioactive waste from damaged fuel rods. If cooling water feeds continue at current rates, there will be another 8,000 tons of highly radioactive water to be taken care of by the time AREVA’s treatment plant starts up — that is, if all goes according to plan…

A “mega-float” that has been towed to the site for storing and transporting radioactive water can probably only be used for decontaminated water (i.e. with 99.9% of the radioactivity removed), otherwise radiation would be too high to handle. Contaminated water being pumped from the basement of the turbine buildings to storage tanks gives off so much radiation that the piping is covered up with lead wool wherever people have to walk over it and is cordoned off with security tape everywhere else.

If a water pump fails and it has to be replaced, someone will have to disconnect and reconnect pipes to pumps that carry billions of becquerels of radioactivity per liter of water. There will be leaks and puddles and spills. This is not how things would be done if there was any choice.

Fukushima 1 may not make the headlines of the world media much any more, but the situation there is still nightmarish. It’s not the TEPCO managers who are paying for their company’s gross negligence, but unnamed workers of hired subcontractors who are risking their lives and health.

The cleanup and compensation for thousands who lost their homes and incomes through the fallout far exceeds TEPCO’s ability to pay, so tax payers will be forced to pay the bill, yet the government chose not to force TEPCO into bankruptcy. Its share price may have fallen, but its stock did not become worthless as say General Motors in the US car industry bail-out, or perhaps the crops grown by farmers nearby or the now deserted homes owned by families around the plant. TEPCO’s well-connected shareholders were effectively bailed out by the government at our expense.

See also: