Maritime investigators in the Solomon Islands have revealed key evidence from a grounded ship that's leaking oil was taken in the aftermath of the disaster without their knowledge.
They say they were "shocked" to learn the voice data recorder had been seized by the vessel owner and taken to Australia without their knowledge.
Bag after bag of oil-covered sand loaded up and shipped out. It's time consuming manual labour.
"It's thick, it's sticky but it doesn't take to water very kindly so therefore it's easy to coagulate I suppose," Mark Williamson, Pacific Project Logistics, told Newshub.
More than 100 tonnes of oil has leaked out of the Solomon Trader after it hit a reef while loading bauxite - soil used to make aluminium.
"In the context of the Solomon Islands...it is serious...it is serious," Director Maritime Safety Administration, Jonah Mitau, said.
On the night it hit the reef, the weather was poor. The vessel owner says at the time, the ship was "fully crewed".
But investigators believe the person on anchor watch didn't alert the captain quickly enough to the impending disaster.
"The lookout on that night... There may be a failure with the lookout on the night," Mitau said.
Of more concern to investigators is the vessel's voice data recorder - taken without their knowledge.
"We are in shock. It is the equipment I send my investigators over to Rennell to try and retrieve it and suddenly we learn that it is in Australia," Mitau said.
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The vessel's insurer told Newshub that due to "acts of vandalism and theft after the vessel's grounding, an owner's representative considered it prudent to remove and safeguard the voice data recorder".
It says it informed local police - but Mitau says what's happened is "unusual".
"Exactly the same as the black box on the planes - the first person to remove it would be the investigators and not whoever else," Mitau said.
Negotiations are now taking place so the downloading of audio can be witnessed by both parties.
Back on the beaches, locals say the crisis is due to government allowing mining firms to act irresponsibly for too long.
"They just forget our voice...So this leader is just interested in getting money without considering what will affect the local people," resident, Ezekiel Kago'vai, said.
Newshub has been told 200 people from just one tribe have made complaints about the mining and the law not being enforced, but that the Government took no action.
Repeated requests have been made to the Prime Minister for an interview, but his office has told us he's too busy preparing for the upcoming election.