Between now and Christmas, salvors expect to recover around 4000 tonnes of it. Large chunks, located by divers working at 30-40 metres below the surface, will be hauled from the bottom using large hydraulic grabs.
In a single day, they can expect to retrieve about 50 tonnes of scrap, in loads as large as 6 tonnes at a time.
Once back at port, the debris will be destined for recycling or landfill.
Over the past 17 days, the same barge that was used to carve the Rena's towering accommodation block into pieces has been converted for the new task. Mr Tong expected to put it into action by next week.
"Conceptually, it's been in the making for a long time, and now it's about putting it all together quickly."
Yesterday, salvors were putting the last touches to the 91m-long RMG 1000 and transferring hefty mooring equipment that would hold it in place.
Its 25-strong crew worked at the mercy of swell conditions.
Mr Tong said each job came with its own hurdles to overcome.
"It's challenging ... but it's not unbeatable," Mr Tong said.
A ruling on the Waitangi Tribunal Hearing regarding the Government's handling of the Rena disaster is expected today. The hearing was urgently requested by Motiti Island iwi and was held at Trinity Wharf Hotel at the start of this month