Update #11: May 31st, 2011
Nelle's comment: Again we see the odd statement that the temperature of spent fuel pool is only around 70°C (30° below the boiling point), yet this is supposed to be producing enough steam to saturate the air in Unit 2 to 99.9% humidity to the point where it is raining inside the structure? I simply do not understand this. Also remember in an earlier story TEPCO admitted they weren't sure this heat exchanger system would work to reduce the steam and high temperatures that are inhibiting work at the plant. We will see.
Cooling system operating at No. 2 reactor
"The operator of the troubled Fukushima Daiichi nuclear power plant has started operating a system to effectively cool water in a spent fuel pool in the plant's No.2 reactor building.
The Tokyo Electric Power Company on Tuesday set up at the building the first circulatory cooling system to be installed at the plant since the accident in March.
The utility has been pumping about 50 tons of water into the pool every few days.
The pool's temperature is around 70 degrees Celsius, apparently producing steam that has filled the building and resulted in a humidity level of 99.9 percent.
The humidity and high radiation levels have been hampering repair work at the site.
The new system is to pump water out of the pool to a heat exchanger and return the water to the pool as coolant.
The firm says it plans to lower the pool's temperature to around 40 degrees Celsius in a month and hopes to reduce the humidity level before installing equipment to remove radioactive substances in the building. The firm says it will start operating similar systems at the plant's No.1 and 3 reactors in June, and at the No.4 reactor in July."
Tuesday, May 31, 2011 20:57 +0900 (JST) http://www3.nhk.or.jp/daily/english/31_42.html
The rest of the stories are about CONTAMINATION.
High radioactivity levels at No.1 reactor
"The operator of the damaged Fukushima Daiichi nuclear power plant has reported high levels of radioactive substances in water that has accumulated in the basement of its Number 1 reactor.
Tokyo Electric Power Company says a water sample taken from the reactor building's basement on Friday contained 2.5 million becquerels of radioactive cesium-134 per cubic centimeter. It also detected 2.9 million becquerels of cesium-137 and 30,000 becquerels of iodine-131.
The levels are almost the same as those already measured in contaminated water in the basement of the Number 2 reactor's turbine building.
Water contaminated with highly radioactive substances has flooded the reactor building's basement, apparently after leaking from holes created in the reactor's pressure and containment vessels in the fuel meltdown.
Under the utility's plan to bring the plant under control, a circulatory cooling system is to be installed to decontaminate radioactive water and use it as a coolant.
TEPCO says it will examine ways to decontaminate the water, as its radiation levels are too high for workers to approach."
Monday, May 30, 2011 22:25 +0900 (JST) http://www3.nhk.or.jp/daily/english/30_32.html
Nelle's comment: Is it just me or do the following plans to filter the ocean seem a bit unrealistic?
Seawater purifiers to be set at Fukushima plant
"The operator of the damaged Fukushima Daiichi nuclear power plant says it will install equipment to purify highly radioactive seawater near the reactors' water intakes.
Tokyo Electric Power Company says it will start work on Tuesday to install seawater purifiers, which use the mineral zeolite to absorb radioactive cesium.
The utility previously built undersea silt barriers around the water intakes for the No.2 and 3 reactors after highly contaminated water was found to be leaking into the sea.
But radioactive substances exceeding the government-set safety limits are still being detected both inside and outside the barriers.
To stop contamination entering the sea, TEPCO decided to install new equipment to decontaminate seawater.
It is planning to draw and treat a maximum of 30 tons of water per hour from inside the silt fences, where radiation levels are higher, aiming to reduce contamination in the water outside the fences.
The company says the equipment will be installed around the intakes of the No.2 and 3 reactors, and it will begin preliminary operations as early as Thursday."
Tuesday, May 31, 2011 06:03 +0900 (JST) http://www3.nhk.or.jp/daily/english/31_02.html
Rain increases radioactive water at nuke plant
"Heavy rain has increased the volume of highly radioactive water building up inside the disaster-hit Fukushima Daiichi nuclear plant.
Contaminated water already floods the basements of the turbine and reactor buildings, partly due to water injections to cool down the reactor cores.
Tokyo Electric Power Company, or TEPCO, now says water levels rose faster on Monday as rain poured inside the badly damaged buildings.
In the basement of the No.1 reactor building, radioactive water rose by 37.6 centimeters during the 24 hours through Tuesday morning.
At the No.2 reactor, the level of water rose by 8.6 centimeters in an underground tunnel extending from the building.
The water in the tunnel's shaft is now only about 39 centimeters below ground level. The utility is speeding up work to seal the opening.
TEPCO is planning to decontaminate and recycle the radioactive water as coolant for the reactors. But the system won't be in place until July at the earliest.
In the meantime, the utility is studying steps to prevent rainwater from seeping in. It will also consider new storage sites to which the contaminated water can be quickly transferred as the rainy season approaches."
Tuesday, May 31, 2011 12:32 +0900 (JST) http://www3.nhk.or.jp/daily/english/31_13.html
TEPCO tackles increasing contaminated water
"The operator of the damaged Fukushima Daiichi plant says water accumulating in the basement of the No. 1 reactor building is contaminated with highly radioactive substances. The utility is battling to stop further leaks as the rainy season approaches.
Tokyo Electric Power Company detected 2 million becquerels of radioactive cesium per cubic centimeter of water in the basement of the No. 1 reactor building.
It speculates that radioactive substances from the melted fuel have leaked from the pressure vessel encasing the reactor core.
Large amounts of contaminated water in the plant's buildings are hampering efforts to contain the situation.
TEPCO has created a map showing the distribution of contaminated water at the plant to prevent a recurrence of the accident in March, where 3 workers were exposed to radiation by stepping in contaminated water in the basement of the No. 3 reactor's turbine building.
Rain showers that began Sunday are causing the water levels in the No. 2 and 3 turbine buildings to rise at a faster pace of 3 to 4 millimeters per hour.
The company plans to set up a cooling system to circulate decontaminated water back into reactors. The system is expected to be set up in July.
Until then, the utility needs to come up with measures to prevent further leakage, such as transferring the water to a new storage site."
Tuesday, May 31, 2011 06:03 +0900 (JST) http://www3.nhk.or.jp/daily/english/31_03.html
Nelle's comment: Here is the "map" of Unit 2 from JAIF report release yesterday. The pink areas are puddles of radioactive water. The note describes the one at the lower left as "like light rain." The contamination units are in microSv. I haven't found the map of Unit 1 yet.
This article, written by the former editor of Japan Times Weekly speaks for itself.
Who Will Take the Radioactive Rods from Fukushima? By Yoichi Shimatsu
http://www.globalresearch.ca/index.php?context=va&aid=25064
Global Research, May 31, 2011, 4th Media Beijing – 2011-05-30
"The decommissioning of the Fukushima 1 nuclear plant is delayed by a single problem: Where to dispose of the uranium fuel rods? Many of those rods are extremely radioactive and partially melted, and some contain highly lethal plutonium.
Besides the fissile fuel inside the plant's six reactors, more than 7 tons of spent rods have to be removed to a permanent storage site before workers can bury the Fukushima facility under concrete. The rods cannot be permanently stored in Japan because the country's new waste storage centers on the northeast tip of Honshu are built on unsuitable land. The floors of the Rokkasho reprocessing facility and Mutsu storage unit are cracked from uneven sinking into the boggy soil.
Entombment of the rods inside the Fukushima 1 reactors carries enormous risks because the footing of landfill cannot support the weight of the fuel rods in addition to the reactors and cooling water inside the planned concrete containment walls. The less reactive spent fuel would have to be kept inside air-cooled dry casks. The powerful earthquakes that frequently strike the Tohoku region will eventually undermine the foundations, causing radioactive wastewater to pour unstoppably into the Pacific Ocean. The rods must therefore go to another country.
American Bad Faith
Under the Non-Proliferation Treaty (NPT), signed by Japan in 1970, Washington's negotiators stipulated that used nuclear fuel from Japanese reactors must by law be shipped to the United States for storage or reprocessing to prevent the development of an atomic bomb. Washington has been unable to fulfill its treaty obligations to Tokyo due to the public outcry against the proposed Yucca Mountain storage facility near Las Vegas…." Read More