The deadly remnants of a war that won't go away

Eighty years after the end of World War II, leftover munitions have been dubbed the problem that will never be fixed. 

Cities have been rebuilt, borders redrawn - but there's still an estimated 1.6 million tonnes of ordinance on ocean floors. Some experts say there's a lot more than that. 

The New Zealand Navy is doing its part to whittle down that number, taking part recently in a joint operation near a lagoon in Tuvalu to remove 22,500 pound AN-M43 aerial bombs most likely dumped there by the US military at the end of the fighting in World War II. Operation Render Safe was run by the Australian Navy, with Canada and US Marines also taking part.

However the Tuvalu find is a drop in the ocean of a project that may never end.  

And ERW - or explosive remnants of war - are also a clear and present danger on land. Some of our Pacific Islands are still in dire need of a clean up.

"I don't even think you could put enough zeros on how much would be needed to do it properly," says RNZ Pacific journalist Koroi Hawkins. He grew up in the Solomon Islands where WWII relics were, and still are, part of the landscape. 

"How many millions of dollars would you need to go through those salvage and secure operations? There's just not, at the moment, any political will to be doing any of that stuff, because there's so much out there." 

He talks to The Detail about life growing up with gunpowder as a regular feature; the continuing loss of life and limb as old ordnance explodes; and the proliferation of it throughout the islands around where the battle of Guadalcanal took place.  

The Detail also talks to Lieutenant Commander Simon Marston, the officer in charge of the dive group at HMNZS Matataua, which is the specialist unit that took part in Operation Render Safe. New Zealand has an equivalent operation, called Pukaurua. 

Every two years the unit tries to get up to the islands to do some work around removing old ordnance. While they're there diving for bombs, they lay the groundwork for the next trip, talking to elders who have had passed down to them the locations of dumped munitions. 

"It's not always as easy as a government saying, 'We've got all this stuff we need to get rid of, can you please come and do it?' There are other considerations...in Vanuatu for example these things are at the entrance to the port. So if we start closing down ports that have cruise ships alongside, it becomes quite messy."    

Some high-end support is also needed for the people doing the defusing - including a helicopter on standby for evacuations and specialist medical people on hand. 

"Really the amount of work ourselves, the ADF, US and other countries that are involved [have done]...we really haven't skimmed the surface of it to be honest. It's not gone away." 

Dr Margo Edwards is a marine geologist at the University of Hawaii who's been involved in projects finding and mapping munitions - many of them chemical weapons.

"People are moving further out into the oceans," she says. 

"When these things were first disposed, most of them were intended to be at depths that people would never reach. I don't think they were conceiving of undersea cables, or wind power installed at sea - so we are expanding our reach into the ocean and that's why we are encountering these legacy items."

Some in shallow water are encrusted in corals and a very labour-intensive method called 'cut and capture' is used to neutralise them. A small hole is made in the metal casing and the dangerous contents are sucked out.

"But the alternative is to destroy all the animals that have formed a habitat after decades on the munitions - and that's in some ways even worse than have the constituents leak out into the environment." 

Those constituents include explosive chemicals like TNT, and chemical agents like mustard that were meant to explode and create aerosols that would harm the enemy. 

The danger to us now depends on where in the world you are, how deep the munitions are, how damaged they are, and what environmental conditions they're in. 

There have been efforts to encase them in concrete, or blowing them up where they are, or use remotely operated vehicles to pick them up from the bottom and bring them up to the surface where chemical neutralisation processes that didn't exist in the 1940s can be used. 

"The options back then [for disposal] were not ideal," she says. 

"You basically could bury them, which meant if they leaked because of corrosion they could potentially leak into a water table which would be bad." 

They could also be burnt in very fancy ovens, but that risked explosion. Or you could dispose of them in the sea, which is about 70 percent of the planet. 

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