TWO polar bears break into an igloo and consume the unhappy occupants. "I love these things," confesses one. "Crunchy on the outside, chewy on the inside." The cartoons of Gary Larson can be a useful preparation for life.

So too can a university education. College cultivates independence, self reliance and, albeit informally, an understanding of the amount of alcohol one can happily consume without being ill.

Unlike Larson, however, college does not usually teach coping with polar bears. Apart from a handful of zoologists, most students knowledge of the area extends no further than the fact that they are large, white and unhappy in Dublin Zoo.

Not many students have stood on Arctic ice with an armed guard behind them in case of polar bears who find Larson funny. This summer UCD PhD students Ciara McMahon from Malahide and Luis Leon Bintro from Barcelona added their names to that small, illustrious few.

"I was working on a platform near the ice," says McMahon. "We had fireworks, low grade dynamite, to throw at any curious bears. I don't know if I'd have been able to if I'd had to." Luckily the only bears seen were spotted from a helicopter.

McMahon and Leon Bintro were engaged in what one EU official has described as the most sensitive project ever funded by the Commission.

The Radiation Physics Research Group in UCD's department of experimental physics, under the leadership of Dr Peter Mitchell, is coordinating development of an advanced model to predict the environmental consequences of the dumping of nuclear waste in the Arctic Shelf Seas by the former Soviet authorities. The 3.4 million ECU project, half funded by the institutions themselves and due to finish in 1999, is known as ARMARA (Arctic Marine Radioecology).

"We are looking at the various mechanisms operating in the water column and the sediment column underneath to find out what happens to plutonium and a number of other long lived radionuclides over time," says Mitchell. The project is a coup for UCD's experimental physics department which recently developed the State's first dating facility.

Seven nuclear submarines with their reactors intact were dumped in the Arctic Seas by the former Soviet Union. The hulks, along with other nuclear waste, are now quietly corroding at the bottom of the sea. The casing on the reactors is already deteriorating and radiation will eventually find its way into the food chain unless something is done.

UCD, along with 12 other European institutions, is trying to predict what will happen in order that preventive steps can be taken. One possibility is that the submarines may be raised and their reactors removed for reprocessing.

So it was that McMahon found herself on the Swedish icebreaker Oden for a chilly six and a half weeks earlier this year, while Leon Bintro endured 11 distinctly nippy weeks on the German research vessel, Polarstern.

"The scenery was very beautiful," says McMahon. "Out on deck alone you could swear that you were the only person left on the planet."

There were over 90 people on the Polarstern, including 51 scientists. The smaller Oden had about 75 people aboard, 34 of them scientists. The two ships met only twice during the expedition. Everyone shared a cabin with one other person and there was no choice in the partner assigned. Both Leon Bintro and McMahon say they were lucky in their cabin mates.

"We were told by the crew that, if you go on trips for six months, you can't even say `Good morning' to anyone by the end of the trip without them taking it the wrong way," says McMahon.

The scientists worked in the 24 hour daylight of the Arctic summer. Temperatures were usually between -2 and -3, although it dropped as low as 10".

Much of the Arctic ice is up to 1.5 metres thick, but it can be thicker. "It was difficult to advance if the ice was more than two or three metres thick," says Leon Bintro. "Then the ship had to move backwards and forwards to get through."

McMahon was interested to note that "the ice layer appears blue. It's the snow that gives it the white colour. As the ship breaks through it turns over huge chunks of ice, like blue cake with white icing."

A total of 75 sea water samples were collected at 41 locations, as well as samples of sediment from depths of between 3,000 and 4,000 metres. "Taking water from 2,000 metres was more difficult," says Leon Bintro. "We were using 36 10 litre bottles sent down in a special frame and each bottle had to be closed electronically at the required depth."

Back in UCD, the samples will be analysed in a total of 250 separate radiochemical determinations.

THE work may have been intense, but life on board was not without its lighter moments. A barbeque with mulled wine was held on the ice there were videos and gym machines on the ships and McMahon amused herself at one point by building a snow penguin.

Fresh fruit ran out in the first weeks of the expedition which in a less enlightened age would have led to scurvy and mutiny However the food was generally very good

As Leon Bintro puts it when you're out on the ice for 11 weeks with the same people there isn't a whole lot else to look forward to.