An iconic chimney in Wollongong will come down like 14 tonnes of bricks, and surrounding residents fear a shower of toxins will descend with it.
The Port Kembla Copper stack will be demolished on Thursday with explosives used to bring the stack down, which will occur between 8.45am and 11am.
Police, State Emergency Service volunteers and the police helicopter will help with the delicate operation, including the evacuation of residents within the 300m exclusion zone.
Residents fear the chimney has not been properly assessed for asbestos.
Concerned resident Julie Renshaw said levels four to 22 of the stack were not accessible and not guaranteed to be asbestos free.
She said her main concern was the pre-school across the road from the site.
"They have been contacted by (Port Kembla Copper)," she told AAP.
"But as far as liability goes for the future ... our concern is, worse case scenario one of these children does develop a respiratory illness, there is no support for them at all."
However, Port Kembla Copper's Ian Wilson said there was only a very "fine patina of material adhering to the bricks".
"PKC is doing everything it can to demonstrate to everybody's satisfaction that the stack does not contain residual asbestos hazard," he told ABC Radio.
Wollongong City councillor Vicki Curran put forward an urgent motion on Monday night to stop the demolition because of life-threatening hazards.
The motion was not passed.
Ms Curran said there had not been an adequate asbestos assessment of the entire stack, only the bottom levels.
"We are going to see 14-tonnes of brick rubble and dust being dispersed by explosion into our atmosphere," she told AAP.
PKC will wet down dust as it is created to minimise the chances of dust leaving the site.
