"Ironically it will probably end up as part of the fill required back in Tory Street."
That fill will be poured into a hole left from the demolition process.
Becker said the building's foundations would be dug out including a small area of ground that is contaminated.
Wellington City Council project manager Gunther Wild said the same process would be undertaken at 61 Molesworth Street.
He said in total there was 6000 tonnes of demolition rubble and 300 tonnes of that was steel.
"We are looking to sort through as much of that as possible so pulling out any steel, copper and aluminum," he said.
Meanwhile, one of the nine cars trapped in the Reading Cinema car park can now be seen as demolition progresses.
It was deemed too unsafe for the car's owners to rescue their vehicles from the claws of demolition excavators.
However, Becker said the cars would not be crushed along with the rest of the building if it could be managed.
He said the cars would be plucked out and made available to owners and insurance companies.
"When the excavator gets to the point where the car is located they'll make the effort to retrieve the car. It will be with the excavator equipment so the car will sustain some damage.
"They'll remove it and then place it in a bin to capture the cars and make sure any fluids like petrol or oil or diesel is contained."
Becker said the cars would likely be write-offs but that would be determined on a case by case basis.
"There's no point in needlessly destroying something if you can find another way."
