The Lepse is a more menacing ship now than she ever was when she patrolled the Atlantic as part of the Soviet Navy. In her hold lie scores of spent fuel rods that once drove Soviet nuclear icebreakers through the polar seas. Most are slotted into special insulation tubes. Some overheated, expanded and bent in the nuclear acci dents which plagued the icebreaker fleet. With cavalier insouciance to the danger, Russian workmen went in with sledgehammers in an attempt to force them down the tubes. They shattered and fell to the bottom of the Lepse's storage hold, where they now lie, emitting huge doses of lethal radiation.

The Soviet authorities simply covered the converted hold with a thick layer of concrete, hoping the problem would go away. They planned to tow the ship out and scuttle her. But since Chernobyl the Russians have become acutely concerned by their appalling nuclear safety record. Instead, the directors of the icebreaker fleet have now called for Western help.

Experts from Britain's Atomic Energy Authority are among those contracted to open the rusting hold, send in robots to extract the lethal rods, encase them in glass and dispose of them deep in Siberia.

Meanwhile, the ship remains moored in the narrow, fog-bound channel in Russia's far north. A collision with the submarines, fishing vessels and warships using Russia's main ice-free port, could trigger a nuclear catastrophe. It is the sort of disaster that Western environmentalists believe could now happen in scores of ageing reactors across the former Soviet Union. This is the nightmare that brought President Clinton, John Major and leaders of the world's most powerful nations to Moscow at the weekend to offer President Yeltsin help in cleaning up and making safe his polluted country.

Murmansk, the destination for the wartime Arctic convoys, is a desolate place. Scarred by shoddy postwar reconstruction, it is a city that grew rich on the secretive Soviet military build-up, but now lives in fear of the deadly radiation it thinks will leak from the 185 nuclear reactors ­ submarine, civilian and military ­ scattered around the region. The radioactivity dumped off the Murmansk coast accounts for two thirds of all the radioactive waste ever dumped in all the oceans of the world.

The Lepse has become a symbol of a nuclear problem. The genial captain has grown used to the crude radioactive warning dangling from a rope on the quayside. He now barely notices the nearby Lenin, the former icebreaker and pride of Khrushchev's Soviet Union, that 30 years ago kept the northern sea routes to Japan open all winter. The ship stands, rusty and forlorn, waiting to be scrapped. The Soviet attitude to nuclear safety was even more alarming then: after the reactor overheated, they cut a hole in the hull and dropped it in the ocean.

The icebreaker fleet is now more modern. The Russians showed off their latest Finnish-built ship, her nuclear heart encased in glass and constantly checked. But where will the spent fuel rods be stored? The old storage tanks are full, the sea is now out of bounds and the land is too contaminated.

The civilian fleet admits its nuclear problems, at least. The worry is the submarine fleet of more than 70 boats is idling in harbour, with the old nuclear reactors still intact and still dangerous. The navy would like Western help, but does not welcome prying eyes. I toured the old harbour on a bleak dark day last October; in future, the most dangerous waste dumps may be off-limits. Few will then know what dangers still lurk there .

MICHAEL BINYON