2011-03-18 11:20

An aerial view taken from a helicopter from Japan's Self-Defence Force shows damage sustained to the No 4 reactor (C) at the Fukushima Daiichi nuclear power complex in this handout taken March 16, 2011 and released March 17, 2011. [Photo/Agencies]

TOKYO - Japanese engineers raced to restore a power cable to a quake-ravaged nuclear power plant on Friday in the hope of restarting pumps needed to pour cold water on overheating fuel rods and avert a catastrophic release of radiation.

Officials said they hoped to fix the cable to two reactors on Friday and to two others by Sunday, but said work would stop in the morning to allow helicopters and fire trucks to resume pouring water on the Fukushima Daiichi plant, about 240 km (150 miles) north of Tokyo.

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"Preparatory work has so far not progressed as fast as we had hoped," an official of plant operator Tokyo Electric Power Co (TEPCO) told a news briefing, adding that engineers had to be constantly checked for radiation levels.

Washington and other foreign capitals have expressed growing alarm about radiation leaking from the plant, severely damaged by a magnitude 9.0 earthquake and tsunami a week ago that triggered a series of destructive explosions and compromised the nuclear reactors and spent fuel storage tanks.

Worst case scenarios would involve millions of people in Japan threatened by exposure to radioactive material, but prevailing winds are likely to carry any contaminated smoke or steam away from the densely populated Tokyo area to dissipate over the Pacific ocean.

US President Barack Obama said the crisis posed no risk to any US territory. He nevertheless ordered a comprehensive review of domestic nuclear plants.

"We do not expect harmful levels of radiation to reach the United States, whether it's the West Coast, Hawaii, Alaska, or US territories in the Pacific," Obama said. "That is the judgment of our Nuclear Regulatory Commission and many other experts."

Yukiya Amano, head of the Vienna-based International Atomic Energy Agency (IAEA), was due back in his homeland later on Friday with an international team of experts after earlier complaining about a lack of information from Japan.

Graham Andrew, his senior aide, called the situation at the plant "reasonably stable" but the government said white smoke or steam was still rising from three reactors and helicopters used to dump water on the plant had shown exposure to small amounts of radiation.

"The situation remains very serious, but there has been no significant worsening since yesterday," Andrew said.

Even if TEPCO manages to connect the power, it is not clear the pumps will work as they may have been damaged in the earthquake or subsequent explosions.  

US officials took pains not to criticise Japan's government, but Washington's actions indicated a divide with its close ally about the perilousness of the world's worst nuclear accident since the Chernobyl disaster in 1986.