BHP Stack Removal
- Locations Olympic Dam Mine, Roxby Downs, South Australia
- Client BHP
- Contract High Risk Stack Removal
- Cost $150,000
- Duration 2 Weeks
Demolition and removal of 90 metre high stack
McMahon Services were engaged by BHP to undertake this high risk stack demolition project due to our experience with similar works and our ability to quickly mobilise a professional team to site. The 90m high stack had buckled at the base, creating a severe safety issue as the 20 tonne weight of the stack could potentially collapse at any given time.
The 90m stack was to be removed in addition to a 20m elbow stack towards the base that fed into a filtration plant. The main steel structure supporting the stack was to remain. Scaffolding was erected the entire way up of the 90m stack in 15m sections. At these 15m sections, the stack was braced to four points of the supporting structure for additional support.
McMahon Services removed the stack with precision oxy cutting in 2m sections beginning at the top and working down. Each section once cut was lifted out using a 250 tonne crane and brought to ground for BHP to dispose of on-site.
Challenges
The main challenge faced with this project was the extreme winds. Winds exceeding 10% meant that no crane lifts were possible, therefore the duration of the project was pushed out slightly, ensuring safety was top priority.
