Contractors will use explosives to break up and clear massive boulders brought down onto the Milford Road by a major landslide at the weekend.
Drilling rigs have been moved to the site and have been working to drill holes into the boulders.
The next step would be to drop high powered explosives into the drill-holes, in order to break boulders up to 200 tonnes in weight into pieces small enough to be removed from the site.
Just how long the job will take depends on the weather, but officials hope to have the road open to a single lane by Wednesday.
Photo: NZ Herald