The Tokyo Metropolitan government simply announced on November 24, 2011 that it will be accepting the disaster debris from Onagawa-machi in Miyagi Prefecture starting early December and lasting till March 2013, and the debris (which is radioactive, by the way) will be burned in the waste incineration plants operated by the 23 Special Wards and by municipalities in Tama District (western Tokyo). The agreement has already been signed.
In my November 15 post, I wrote about this deal. But I apparently forgot to write about my speculation at that time (I did in my Japanese blog) that the only reason I could think of as to why the Assembly of the Special Ward Mayors was being consulted in accepting the Miyagi debris was that the debris would be burned in the regular incineration plants in the 23 Wards. I was exactly right, and I don't enjoy having been right on this.
From NHK Kabun tweet:
Debris from Onagawa-machi, Miyagi Prefecture will be brought to Tokyo by the Tokyo 23 Special Wards and municipalities in Tama District of Tokyo starting early next month till March of 2013. 100,000 tonnes of debris will be processed. It will be burned in the waste incineration plants operated by the municipalities, and the ashes will be buried in the landfill on the Tokyo Bay. (November 24)
They are confident that bag filters will reduce or eliminate the radioactive materials on the debris, which will be flammable wood debris, according to the Tokyo Metropolitan Bureau of Environment.
How radioactive it can be? The Bureau of Environment's announcement has a link to the test result of burning the debris and measuring the radiation in Ishinomaki City in Miyagi Prefecture. The number is 2300 becquerels/kg of radioactive cesium in the ashes. Since it is so far below the 8000 becquerels/kg safety standard set by the Ministry of the Environment, there is no problem burning and burying, in the minds of the Tokyo Metropolitan governor and politicians and bureaucrats (and their celebrity supporters...).
By the way, the document from Onagawa-machi makes it clear that the debris may be burned in the private incineration plants in addition to the municipal incineration plants, and that the ashes may be used in "eco-cement".
Again, the only private incineration plant that would meet the spec (more than 100 tonnes per day capacity) is that TEPCO subsidiary, Tokyo Rinkai Recycle Power.