Robot looks inside Japan's toxic wasteland

READINGS from a robot which entered two crippled buildings at Japan's tsunami-flooded nuclear plant for the first time in more than a month displayed a harsh environment still too radioactive for workers to enter.

Officials said the radiation readings for Unit 1 and Unit 3 at the Fukushima Dai-ichi plant do not alter plans for stabilising the complex by the end of the year under a "road map" released by the plant operator on Sunday.

Workers have not gone inside the two reactor buildings since the first days after the plant's cooling systems were damaged by a catastrophic earthquake and tsunami on 11 March. Hydrogen explosions in both buildings destroyed their roofs and littered them with radioactive debris.

A US-made robot entered the buildings on Sunday and took readings for temperature, pressure and radioactivity. More data must be collected and radioactivity reduced before workers are allowed inside, said Hidehiko Nishiyama of Japan's Nuclear and Industrial Safety Agency.

"It's a harsh environment for humans to work inside," he said.

It is still possible, he added, to achieve plant operator Tokyo Electric Power's (Tepco's) goal of a cold shutdown of the plant within six to nine months, as laid out in a timetable the company announced yesterday.

"I do believe we must be creative to come up with ways to achieve our goals," Mr Nishiyama said. "I still think the plan... is as appropriate as we can get at the moment."

Tepco official Takeshi Makigami said the robots must pave the way for workers to be able to re-enter the building.

"What robots can do is limited, so eventually, people must enter the buildings," he said.

As work continued inside the plant to reduce radiation levels and stem leaks into the sea, the defence ministry said it would send about 2,500 soldiers to join the hundreds of police, fitted with protective suits, who are searching for bodies in tsunami debris around the plant.

As of yesterday, searchers had located 66 bodies and recovered 63, police said.

The earthquake and tsunami have left more than 27,000 people dead or missing.

The robots being used inside the plant, called Packbots, are made by the iRobot company of Bedford, Massachusetts. Travelling on tank-like treads, the devices opened doors and explored the insides of the reactor buildings, coming back with radioactivity readings of up to 49 millisieverts per hour inside Unit 1 and up to 57 millisieverts per hour inside Unit 3.

The legal limit for nuclear workers has more than doubled, since the crisis began, to 250 millisieverts.

Tepco's plan for ending the crisis, drawn up on government orders, is meant to be a first step towards allowing some of the tens of thousands of residents evacuated from the area around the plant return to their homes.