Radiation level in plant still dangerous, robots report

A PAIR of thin robots on treads sent to explore buildings inside Japan’s crippled nuclear reactor came back with disheartening news: radiation levels are far too high for repair crews to go inside.

Nevertheless, officials are hopeful they can stick to their “roadmap” for cleaning up the radiation leak and stabilising the Fukushima Dai-ichi plant by year’s end so they can begin returning tens of thousands of evacuees to their homes.

“Even I had expected high radioactivity in those areas. I’m sure (plant operator Tokyo Electric Power Co) and other experts have factored in those figures when they compiled the roadmap,” chief cabinet secretary Yukio Edano said.

Officials said radiation had spiked in a water tank in Unit 2 and contaminated water was discovered in other areas of the plant.

They also described in detail for the first time the damage to fuel in three troubled reactors, saying pellets had melted.

That damage, sometimes referred to as a partial meltdown, had already been widely assumed, but the confirmation, along with the continued release of radiation from other areas, serves to underscore how difficult and how long the cleanup process will be. In fact, government officials acknowledge there are many setbacks that could crop up to slow down their timeline.

Angry at the slow response to the nuclear crisis and to the earthquake and tsunami that caused it, politicians tore into Prime Minister Naoto Kan.

“You should be bowing your head in apology. You clearly have no leadership at all,” Masashi Waki, from the opposition Liberal Democratic Party, shouted at Kan.

“I am sincerely apologising for what has happened,” Kan said.

Workers have not been able to enter the reactor buildings since the first days after the cooling systems were wrecked by the March 11 earthquake and tsunami that left more than 27,000 people dead or missing. Hydrogen explosions in both buildings in the first few days destroyed their roofs and scattered radioactive debris.

On Sunday, a plant worker opened an outer door to one of the buildings and two Packbots, which resemble drafting lamps on tank-like treads, entered. After the worker closed the door, one robot opened an inner door and both rolled inside to take readings for temperature, pressure and radioactivity. They later entered a second building.

The robots reported radioactivity readings of up to 49 millisieverts per hour inside Unit 1 and up to 57 inside Unit 3, levels too high for workers to realistically enter.