Tuesday 20 August 2013

Fukushima news



Radiation levels in 

Fukushima bay highest 

since measurements 

began - reports


Readings of tritium in seawater taken from the bay near the crippled Fukushima nuclear plant has shown 4700 becquerels per liter, a TEPCO report stated, according to Nikkei newspaper. It marks the highest tritium level in the measurement history.



RT,
18 August, 2013

Tokyo Electric Power Company (TEPCO) has detected the highest radiation level in seawater collected in the harbor of the crippled nuclear plant in the past 15 days, Nikkei reports.

TEPCO said the highest radiation level was detected near reactor 1. Previous measurements showed tritium levels at 3800 becquerels per liter near reactor 1, and 2600 becquerels per liter near reactor 2. The concentration of tritium in the harbor’s seawater has been continuously rising since May, according to Nikkei.

Tritium is a radioactive isotope of hydrogen which is produced by nuclear reactors. It is potentially dangerous if inhaled or ingested. The legal limits for Tritium in terms of becquerels per liter vary from country to country. The World Health Organization has a limit of 10,000 Bq/l, but the European Union’s limit is much lower, at 100 Bq/l.

Also on Monday, a leak of highly contaminated water was discovered from a drain valve of a tank dike located on the premises of the nuclear plant, according to Fukushima’s operator responsible for the clean-up.

The level of radiation at the site was estimated at 100 millisieverts per hour, while the safe level of radiation is 1-13 millisieverts per year, according to ITAR-TASS news agency. The plant’s operator is currently investigating reasons for the leak, TEPCO said in a statement.

Earlier, Tepco admitted that an estimated 20 to 40 trillion becquerel’s of tritium may have flowed into the Pacific Ocean since the nuclear disaster.

Three of the plant’s reactors suffered a nuclear meltdown in March 2011 after a massive earthquake struck the area, triggering a tsunami. The plant has been accumulating radioactive water ever since, as groundwater passing through the premises becomes contaminated.

Protective barriers installed to prevent the flow of toxic water into the ocean have failed to do so. The level of contaminated water has already risen to 60cm above the barriers, which has been a major cause of the daily leak of toxic substances, TEPCO admitted.

Japan’s Ministry of Industry recently estimated that around 300 tons of contaminated groundwater has been seeping into the Pacific Ocean on a daily basis. TEPCO has promised to reinforce protective shields to keep radioactive leaks at bay. 





Fukushima workers contaminated with radioactive dust
Two workers at the crippled Fukushima nuclear plant in Japan were found to have been exposed to radioactive particles – just days after 10 workers were sprayed with radioactive water at the beginning of last week



RT,
19 August, 2013

Two dust monitor alarms rang out in the main operations center in the plant, where radiation levels are normally low enough not to need to wear full face masks, the plant’s operator, Tokyo Electric Power Company, said in an e-mailed statement.

The latest incident comes two and a half years after three of the plant’s reactors suffered a meltdown in Japan’s worst-ever nuclear power disaster.

Two workers who were at the end of their shift and were waiting for a bus out of the site had their bodies wiped down, and full body checks showed the staff members had received no internal contamination.

Although TEPCO said it could not be sure that the sounding of the alarms was definitely connected with the discovery that the workers were contaminated, the incident is being investigated further.

Last week 10 workers were also found to have been contaminated with particles, which TEPCO suspected came from a mist sprayer used to keep staff cool during the hot summer months.

The cooling devises were switched off and workers were also banned from using tap water, which comes from the same source.

Also last Monday a separate alarm, which indicates high radiation levels, went off at the continuous dust monitor installed in front of the main building. As a result workers were instructed to put on full face masks in areas of the site where they had previously not been required to do so. 
Workers wearing protective suits and masks operate a soil improvement work site of the shore barrier to stop radioactive water from leaking into the sea, near the No.1 and No.2 reactor buildings of the tsunami-crippled Fukushima Daiichi nuclear power plant in Fukushima, in this photo released by Kyodo July 22, 2013. (Reuters/Kyodo)
Workers wearing protective suits and masks operate a soil improvement work site of the shore barrier to stop radioactive water from leaking into the sea, near the No.1 and No.2 reactor buildings of the tsunami-crippled Fukushima Daiichi nuclear power plant in Fukushima, in this photo released by Kyodo July 22, 2013. (Reuters/Kyodo)


On August 11, Tepco said that a newly built observation well contained highly toxic water. The well, which was drilled just four meters from the sea on August 7, contained 34,000 becquerels of radioactive tritium per liter.



There is also considerable concern that protective barriers installed to prevent the flow of toxic water into the Pacific Ocean are proving ineffective. Japan’s Health Ministry recently estimated that 300 tons a day of contaminated ground water had been seeping into the Pacific since the disaster in March 2011.

Japan’s Nuclear Regulation Authority has called the situation at Fukushima a “state of emergency” and the government announced earlier this month that it would be becoming more involved in the clean-up work after TEPCO denied for months that radiation was leaking into the Pacific. 


Fuel rod fears


The most serious problem at Fukushima is the removal of the spent nuclear fuel rods, inside the stricken reactor buildings.

The operation, which is planned to begin in November, will be extremely dangerous and complicated because the structure of the fuel pools where the rods are located has been severely compromised. It is also not known to what extent the rods were damaged when they caught fire immediately after the tsunami.

The rods were also corroded when engineers used salt water to cool them, but it is unclear what state they are in. As computer-guided removal is impossible, the job will have to be done manually, Christina Consolo, a nuclear fallout researcher, told RT.

Leaving them in situ is not an option,” Consolo said. “As long as the fuel rods are in their current locations, then they pose an extreme risk as any rod at any time may go critical, which means it will combust and release large amounts of radiation.”

If an event such as a fire or another earthquake occurred, she explained, the rods would be in extreme danger and some experts say that the situation would be so serious that most of northern Japan would be uninhabitable.

Their removal is a job fraught with danger for the workers involved.

My concern would be the physical and mental fitness of the workers who will be in such close proximity to exposed fuel during the extraction process,” said Consolo. “It will be hot and uncomfortable, your senses shielded, and you will be filled with anxiety. Even with the strongest protection possible workers will have to be removed and replaced often.”

TEPCO admitted last month that as many as 10 percent of the workers who have been involved in the cleanup may be at risk of developing thyroid cancer. It also put the number of staff irradiated at 11 times more than estimates it had previously given to the World Health Organization. The total number of workers who have been exposed to dangerous levels of radiation is now being given as 1,978.






Nuclear Watch: Contaminated Water Leaks at Fukushima Daiichi


19 August, 2013



To watch video GO HERE


Title: Nuclear Watch: Contaminated Water Leaks at Fukushima Daiichi
Source: NHK Newsline
Date: Aug 19, 2013
h/t MOXy


At 2:45 in
Yoichiro Tateiwa, NHK reporter: [Professor Jota] Kanda argues government statistics don’t add up. He says a daily leakage of 300 tons doesn’t explain the current levels of radiation in the water.
Jota Kanda, Tokyo University professor: According to my research there are now 3 gigabecquerels [3 billion becquerels] of cesium-137 flowing into the port at Fukushima Daiichi every day. But for the 300 tons of groundwater to contain this much cesium-137, one liter of groundwater has to contain 10,000 becquerels of the radioactive isotope.
NHK: Kanda’s research and monitoring by Tepco puts the amount of cesium-137 in the groundwater around the plant at several hundred becquerels per liter at most. He’s concluded that radioactive isotope is finding another way to get into the ocean. He’s calling on the government and Tepco to identify contamination routes other than groundwater.
Kanda: If we focus on groundwater too much without contemplating other causes, the situation won’t be resolved. There must be routes other than groundwater that are contaminating the ocean. So what we have to do now is consider all possibilities as we figure out a solution to the problem.
NHK: Professor Kanda says the volume of radioactive particles discharged into the ocean is much smaller than the volume released immediately after the accident. But, he says there may be other sources of contaminated water stored up inside the plant’s infrastructure. He says that water is highly contaminated, and if it gets into the ocean it will again have a devastating impact.



Toxic puddles found at Fukushima nuclear plant
Puddles with extremely high radiation levels have been found near water storage tanks at the crippled Fukushima nuclear plant, Japan’s atomic regulator and operator said Monday, according to a report.


20 August, 2013


The radiation level, measured around 50 centimeters above the toxic water, was about 100 millisieverts per hour, Kyodo news agency reported, citing the Tokyo Electric Power Co. (TEPCO).

Around 120 liters is believed to have leaked out from a water storage tank.

TEPCO denied that toxic water had flowed into the adjacent Pacific ocean, but the Nuclear Regulation Authority ordered the utility to study the possibility that it had escaped into the sea through nearby drains.

The NRA released a preliminary assessment that the incident was a level one incident on an eight-point international scale, defined as an “anomaly”.

A low barrier around the tanks is meant to block water when a leak occurs, but drain valves may have been left open, allowing water to flow outside, the report said.

A TEPCO employee found water leaking from a valve at about 9:50 a.m. Monday. One of the puddles outside the barrier had an area of about three square meters and was one centimeter deep.

TEPCO has faced a growing catalogue of incidents at the plant including several leaks of radioactive water, more than two years after the worst nuclear disaster in a generation triggered by a huge quake and tsunami in March 2011.

The company—which faces huge clean-up and compensation costs—has struggled with a massive amount of radioactive water accumulating as a result of continuing water injections to cool reactors.

The embattled utility in July admitted for the first time that radioactive groundwater had been leaking outside the plant and this month started pumping it out to reduce leakage into the Pacific.

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