The mass demolition of more than 1000 Canberra homes contaminated with Mr Fluffy asbestos insulation is poised to begin from next week.
Five Mr Fluffy houses have been earmarked for a pilot study and will be the first demolitions to take place over the coming eight weeks under highly controlled conditions.
The vacant houses are in Farrer, Evatt, Melba and two are in Wanniassa.
Neighbours are currently being doorknocked by members of the Asbestos Response Taskforce to inform them of the impending demolition while the taskforce and WorkSafe ACT work together to manage the process.
A key focus of the pilot is to allow the Taskforce to refine its engagement with the community for the broader demolition program. The demolition of houses will be filmed and the taskforce's engagement activities will be evaluated.
While an eight-week time frame for the demolition has planned, the structural demolition is expected to take less than a day.
The pilot is expected to be completed by the end of July with 50 houses scheduled for demolition as the first tranche of 820 properties agreed to be surrendered in the government's voluntary buy-back program.
Two of the houses are ACT government housing properties while the other three are have been surrendered under the scheme.
Taskforce head Andrew Kefford confirmed that two construction companies, Manteena and Shaw Building Group, had been taken on as project managers for the first 50 homes.
Mr Kefford could not specify how much it would cost for each home to be demolished as they would be individually assessed, based on their levels of contamination. He did not want to compromise what would be a competitive tendering process.
"The overriding consideration in this whole process will be the safety of the community and of the workers doing the activity. Of course, value for money and price is an important consider in what is a very significant program of work for the ACT government."
Just last week a home in Holder was privately demolished while last month a house in Hackett was also privately demolished.
ACT WorkSafe Commissioner Mark McCabe said WorkSafe inspectors monitored both demolitions. He did not know what each demolition cost, but noted that homeowners had had to change contractors midway through the planning process after WorkSafe refused to sign off on the work prior to it starting.
"WorkSafe is committed to ensuring that the removal of asbestos and subsequent demolition of loose-fill asbestos houses will not go ahead unless our inspectors are confident the work can be carried out safely. That is our legislated role and it is the community and the government's expectation. We take those obligations very seriously."
According to the taskforce, the demolition process would be conducted in stages.
Generally in the first 14 days houses would be individually assessed. Site set up and fencing could take five working days, removing the contents of houses up to three working days, while internal asbestos removal, including removal of bonded asbestos also, could take seven days.
The external structural demolition and site remediation could take up to seven days, however actual house demolition would be a day, while site wrap-up could take another four.
Asbestos removed – including loose fill and bonded – would be treated as toxic waste, double-bagged, decontaminated and buried in the asbestos dump at Mugga tip. Internal walls and frames of the house would then be sprayed with a fixative to adhere any other loose fibres before the home was taken down.
All waste from the demolition and house would be buried at the West Belconnen tip – which is expected to receive up to 150,000 tonnes of contaminated material over the demolition program. Waste would be buried under soil at the end of each day with a larger capping of soil for permanent containment.
Mr McCabe said he expected houses would be subject to some plastic containment – although he did not believe houses would be encased in a bubble, as was the case in Downer in 2013 when a house was found to have been missed in the 1988 Commonwealth clean-up.
He said negative air pressure could be achieved using plastic sheeting over roof tiles. Air monitoring would be conducted throughout the process. The house would also be kept wet through mist pumps being used during the duration of the demolition in order to further reduce the potential loose fibres escaping and suppress general dust.
Neighbours were fine to remain on their properties throughout the demolition and ACT Health was also working closely with the taskforce.
Each demolition would include dust air monitoring by a licensed asbestos assessor.
If any concerns were raised by WorkSafe or workers during the work, it will be stopped.
Meanwhile, Mr Kefford said the movement of trucks into and out of suburbs would be planned to try minimise disruptions to the community.
"The safe movement of rubble to disposal sites will be carefully managed and planned and we are working across government to ensure co-ordinated plans are in place."