Bermuda's Airport dump could "poison'' Castle Harbour, says Government Conservation Officer Mr. David Wingate.

Mr. Wingate, who has done extensive work on the Nonsuch Island nature reserve on the edge of the harbour, said floating debris from the metal dump frequently washes up on the island's beach.

Cars and other large metals have long been dumped in the harbour on the edge of the Airport as a way of disposing of the waste while reclaiming land.

Tests conducted by the Bermuda Biological Station for Research Inc. have shown "appreciable amounts of heavy metals and other contaminants'' coming off the dump into the water, Mr. Wingate told The Royal Gazette .

Now, with a tenfold increase in the volumes of waste going to the Airport since the recent closure of the Pembroke Dump, "it's going to be a hell of a lot more, and it's going to start really poisoning Castle Harbour'', he said.

The Royal Gazette recently reported that cars and appliances were being dumped into the harbour without being properly crushed or drained of toxins.

Yesterday, Works & Engineering Minister the Hon. Leonard Gibbons said Government was working "very diligently'' on a plan to have the metals shipped out of Bermuda to a smelter in the United States.

"It's not confirmed yet,'' but "it is a solution,'' Mr. Gibbons said. Nearly all cars came to the dump from dealers and were already drained of fluids when they arrived, he said.

While working on the plan to ship metals abroad, Government continued building an underwater "cell'' out of blocks made from a mixture of Tynes Bay Incinerator ash and concrete, he said. The wall of blocks, which officials have estimated will take a year to build in water 30 to 40 feet deep, would stop the problem of debris floating away from the dump.

Mr. Wingate voiced concerns about that approach as well.

Not only will it take a long time, but "the blocks themselves are a potential source of leachate,'' he said, noting the Bio-Station was also studying that issue.

Mr. Wingate said that several years ago he recommended "a very expensive solution, which is probably why they haven't done it''.

Sheet piling should be used to create "a coralled area'' to contain the metal waste, he said. "At least you would get rid of the float-off problem, and you would also reduce the leaching of pollutants to a great extent to Castle Harbour.'' While the sheet piling would be expensive, it would not cost as much as the incinerator did, he said. "It's a question of how much you value our marine environment, against the cost.'' Even the sheet piling was only "a half solution'', Mr. Wingate said. "The real solution is keeping the really deadly pollutants out of the waste stream by recycling them.'' Mr. Wingate said the deterioration of the beach habitat at Nonsuch Island has been "nothing short of catastrophic'' since the 1960s.

"I've seen an appalling deterioration in that particular habitat. It's manifested in a decline in the use of the beach by shore birds.'' He estimated about one-third of the decline was due to the Airport dump, and the rest due to a general increase in ocean pollution.