Verve Energy engaged CMA Contracting (a Delta Group company) to complete major industrial demolition and remediation works at its Kwinana Power Station in suburban Perth.

The scope of works included:

  • Demolition of existing 140 metre chimney stack and adjacent boiler house structure down to foundation levels – limited to a footprint of 100m x 70m and including a 50m x 60m exclusion zone at the base of the stack.
  • Engineering study, including simulation and modelling for proposed deconstruction methodology.
  • Emissions, noise and vibration controls to protect adjacent structures and operating plant/assets.
  • Remediation and rehabilitation of contaminated soil – including 95% MMDD and 300mm thick limestone layer.
  • Transport logistics, including traffic management and supervision.
  • Recycling of construction waste materials.

Our custom designed, in-house demolition works programme was the first of its kind in Australia and involved a partnership with MB-Abbruchtechnik to fabricate specialised machinery that could deconstruct the stack ‘top-down’ whilst achieving strict emissions, noise and vibration controls. Our solution centered on a shear with a kibble slung from a tower crane attached to the side of the stack and dropping all debris into the kibble or down the centre of the stack.

The second stage of our programme involved an induced collapse of the boiler house structure following the safe removal of large volumes of friable asbestos. Our programme design also took into consideration an adjacent turbine hall structure that was protected by a temporary framework of steel columns and cross-braces as well as concrete footings. The computer modelling and simulation techniques we adopted allowed us to predict how the structure would behave in the initial stationary position and throughout the induced collapse.

Following a successful ‘drop’ we processed and recycled more than 3,000t of construction waste materials before undertaking the remediation and rehabilitation of contaminated soil:

  • Analytical sampling and testing.
  • Soil classification and excavation, including the removal of footings and soil underneath boiler house and chimney stack structures – down to 2.5m – and transport to licensed landfill facilities.
  • Site drainage, set out and placement of engineered fill.