Rena recovery authorities have confirmed oil sheens spotted near Astrolabe Reef last year came from the wreck.
The latest report on the project released yesterday also says the wreck has moved into deeper waters.
The oil sheens, first reported in December, prompted salvors Resolve Salvage and Fire to recover 992 litres of oil trapped within and near the substantially degraded engine room.
"This operation was in response to intermittent oil sheens being observed on the surface during debris clearance operations.