Russia denies Kursk radiation threat

Relatives mourned the sailors deaths last August

MOSCOW, Russia -- Nuclear engineers have denied that there is any chance of radiation leaking during the salvage of the Russian Kursk submarine.

The Russian engineers said there was no possibility of a leak, even if an accident disrupted the salvage effort, The Associated Press news agency reported.

The salvage operation began last week in the Barents Sea to raise the nuclear sub from where it sank last August with 118 sailors on board.

Divers have cut holes in the hull and steel cables will be attached to haul it to the surface.

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The cables will be attacked to 26 hydraulic lifts anchored to a giant pontoon, which will be towed to the Arctic port of Murmansk, AP said

The main fears are that the cables could break, dropping the Kursk back into the sea bottom, or that the submarine would turn upside down during the towing.

Some experts worry about the ability of the Kursk's two nuclear reactors to withstand such shocks, AP said.

However, Nikolai Ponomaryov-Stepnoi, deputy chief of the Kurchatov Institute, Russia's leading nuclear research centre, said that all possible accidents have been studied, and that experts concluded the reactors would remain safe.

"We have reviewed all possible situations that can arise during these operations -- the lifting, towing and placing in the dock -- and we have come to the conclusion that not only under normal circumstances, but even under some kind of trouble, which could occur during any technical operation, the nuclear reactors will remain safe," Ponomaryov-Stepnoi told a news conference on Tuesday.

The Kursk's reactors were designed to withstand enemy strikes, during which "the pressure on the reactor is tens of times stronger than during the most devastating earthquake," said Alexander Kiryushkin, head of the Mechanical Engineering Institute which designed the reactors.

The Kursk was ripped by an explosion and crashed into the sea floor last August, killing all 118 sailors aboard. The cause of the explosion remains unclear, although Russian experts believe a practice torpedo exploded after colliding with another vessel.

An emergency system shut down the reactors, Russian officials said, and no radiation leaks have been reported.