Landowners on sleepy Gambier Island are threatening to use a constitutional challenge in their fight to keep an old naval wreck from being sunk as an artificial reef in the pristine waters of Howe Sound.

It's the latest skirmish in the battle over whether the two thousand ton Canadian helicopter destroyer HMCS Annapolis can be sunk in Halkett Bay -- a divers' paradise that would be the wreck sunk closest to a big city in B.C.

"Nobody wants a lawsuit," said Andrew Strang, one of the landowners. "But we're a determined bunch."

The Annapolis is being cleaned of hydrocarbons and heavy machinery by a group of volunteers with the Artificial Reef Society of B.C.

They expect to pass an Environment Canada review in the next few months, which would give them permission to sink the vessel in Halkett Bay before the fall.

"The shape of the hangar lends itself to a cave, and this will be a natural swim through for divers and an excellent area for rockfish," said Howard Robins, the ARSBC president.

"There's a huge benefit for eco-tourism, divers are excited, and so are we," he said.

But a lawyer representing the landowners says if Environment Canada -- a federal agency -- won't stop the process, he says the provincial government should be forced to step in.

"The Court of Appeal of B.C. has stated categorically that the Province owns (the waters)," Martin Peters wrote in an e-mail to CTV News.

"However, the feds are potentially approving the dumping of naval junk onto the provincial property without any apparent input or concern by the provincial minister of environment," Peters wrote.

A lawsuit, if successful, could reshape the laws around ocean dumping across the country, he said.

Robins said that if the landowners shouldn't worry about pollution.

"People seem to think we're polluting, but we're not polluting," said Robins. "We would never sink a ship if there were pollutants on board. And we do our best to make sure that nothing would hit the water."

Environment Canada's review would be conducted at some point in the summer, he said.

With a report from CTV British Columbia's Jon Woodward