Disposal of quake debris begins


Work to dispose of debris from the quake-ravaged city of Miyako, Iwate Prefecture, began Thursday in Tokyo with about 30 tons arriving on a train at Tokyo Freight Terminal, the first load from Iwate to be accepted by a local government outside the Tohoku region.

The Tokyo Metropolitan Government plans to accept a total of 11,000 tons of debris from Miyako by next March, as part of plans to dispose of a combined 500,000 tons of debris from both Iwate and Miyagi prefectures, the areas hit hardest by the March 11 earthquake and tsunami, by fiscal 2013.

At the terminal in Shinagawa Ward, debris containers were transshipped onto trucks to be carried to a crushing facility in Ota Ward, from where combustibles will be taken to an incinerator in Koto Ward.

Resulting ash and incombustibles are to be used as landfill in Tokyo Bay.

In light of radiation fears among residents, the metropolitan government plans to monitor and release data weekly on radiation levels in the air at the edge of the crushing premises and once a month on crushed waste, ash and exhaust gas, it said.

Its four crushing facilities, incinerator and landfill site are all located in an industrial zone facing Tokyo Bay.

Miyako is located 260 km north of the crippled Fukushima No. 1 nuclear power plant, while Tokyo is roughly 220 km southwest of the plant.

Tepco denies criticality

Tokyo Electric Power Co. said Thursday the detection of radioactive xenon at its stricken Fukushima No. 1 power plant, indicating recent nuclear fission, was not the result of a sustained nuclear chain reaction known as a criticality, as feared, but a case of “spontaneous” fission.

When it revealed Wednesday that it had detected at its crisis-hit No. 2 reactor xenon-133 and xenon-135, which are typically generated by nuclear fission and have relatively short half-lives, it touched on the possibility that melted fuel inside the reactor may have temporarily gone critical.

Tepco has been analyzing the phenomenon, which did not raise the reactor’s temperature or pressure, with support from the Japan Atomic Energy Agency.

The nuclear crisis at the plant, the world’s worst in 25 years, erupted in the wake of the March 11 earthquake and tsunami, and resulted in the meltdown of nuclear fuel in the six-reactor power complex’s reactors 1, 2 and 3.