The documents linked to below contain advice and information to assist in the decision making process for the removal and disposal of potentially contaminated building materials. If the age (pre 1988) and construction of the structure lead a person to believe that the building may contain asbestos, then it should be treated as though it does.
if work is undertaken [such as removal and disposal of asbestos containing material] in a workplace, then the
Code of Practice for the Safe Removal of Asbestos 2nd Edition [OHSC: 2002(2005)]
and the
Code of Practice for the Management and Control of Asbestos in Workplaces [NOHSC:2018(2005)] apply.
CCA treated timber [copper, chrome arsenate] can also pose a risk to health due to residues in the ash.
Rain water tanks can also be affected by bushfire.
http://healthywa.wa.gov.au/Articles/N_R/Rainwater-tanks-after-a-bushfire
Property Hazards After Bushfires.
http://www.greenbushes.crc.net.au/uploads/6/3/2/6/63266341/property_hazards_after_bushfires.pdf
Management of Fire Damaged Asbestos.
http://www.greenbushes.crc.net.au/uploads/6/3/2/6/63266341/management_of_fire_damaged_asbestos.pdf
Asbestos Fire Containment.
http://www.greenbushes.crc.net.au/uploads/6/3/2/6/63266341/asbestos_fire_contamination_brochure-oct2014.pdf