Nitrogen injection for reactor 1~3 stopped again, Tepco reported on 4/7/2012. They started the back-up unit one hour later, but still the reason is not verified. Tepco states, it might be because of the clogging filter.
Nitrogen injection stopped 3 times only in one month. Including the leakage of highly contaminated water, troubles are happening almost everyday.
In this level of radiation, even a disaster dealing robot is collapsed within less than 2 hours. In Fukushima plants, robot called Quince is used, which is developed by Chiba institute of technology and Tohoku university. Assistant professor Mizutani from Tohoku university states, “The bottle neck to develop a robot for radioactive circumstances is the semiconductor.Semiconductor is extremely sensitive for radiation. Semiconductor parts of robot used in space are shielded by lead, which is against gamma ray, but lead can’t be used for Quince because it kills cavalry.Technical specification requires Quince to stand only over 3Sv/h. In total, it’s just over 100Sv.”
With this level of the specification, Quince can’t last longer than 2 hours in reactor2. If it’s 3Sv/h to stand, Quince can’t last longer than 1 hour and 20 minutes.
Aichi Prefecture will accept up to 1 million tons of rubble from earthquake and tsunami-ravaged areas of northeastern Japan.
Aichi is one of 35 prefectures that responded to a central government request by April 6 to accept debris from the Tohoku region.
Aichi's decision came 13 months after the magnitude-9.0 Great East Japan Earthquake.
The central government is seeking to secure agreements from prefectural authorities across Japan to accept some 4 million tons of wreckage from Iwate and Miyagi prefectures.
The government on March 16 sent letters in Prime Minister Yoshihiko Noda's name to 35 prefectures and 10 major cities that had yet to make clear whether they would accept rubble.
In asking for their cooperation, the letters set April 6 as the deadline for a response.
More areas are leaning to helping out, while some are determined not to take part.
In Kyoto Prefecture, five cities and towns, including Maizuru, said they are considering the government's request.
Sapporo rejected the request on grounds the central government is unable to offer guarantees that radiation levels are safe.
Tokushima Prefecture said no municipalities under its jurisdiction intend to accept rubble. It criticized the government for not offering a sufficient explanation.
The government late last month asked eight prefectures and eight major cities that had indicated a willingness to dispose of debris to accept 910,000 tons of rubble.
Tokyo already plans to dispose of 500,000 tons.
Hosono makes new debris plea to Fukushima towns
Environment Minister Goshi Hosono repeated his request Saturday for temporary storage sites to be built in towns around the crippled Fukushima No. 1 plant for radiation-tainted soil and debris before its eventual disposal.
If you build it, they won't come: Environment Minister Goshi Hosono addresses officials from Naraha, Fukushima Prefecture, on Saturday in the town of Iwaki over the central government's plan to build a storage facility for irradiated soil. KYODO
But representatives of Naraha, one of the three towns targeted, refused to budge, according to people who attended a meeting Saturday in Iwaki, Fukushima Prefecture. Naraha's municipal authorities have been based in Iwaki since the nuclear crisis began.
Hosono said the final dump site will be built outside the prefecture, telling Naraha's officials that "this is an issue that has to be resolved by nationwide efforts."
But that wasn't enough to convince them. "How could our children live in such an environment?" one official asked. "Is there any guarantee that government will secure the location for the final dump site?"
Naraha's municipal assembly has unanimously adopted a resolution to oppose the construction of such a storage site in the town.
40,000 tons U.S.-bound
The Environment Ministry said more than 40,000 tons of debris from the March 2011 tsunami are expected to reach North America's West Coast by February 2013.
The debris is part of the 1.33 million tons washed into the ocean from Iwate, Miyagi and Fukushima prefectures.
"Japan is not obligated to recover debris under international law, but we will hold talks with the U.S. and Canada to prevent it from causing problems, such as endangering ships," a ministry official said Friday.
According to ministry estimates, 1.2 tons of half-submerged debris will reach the West Coast around October.