Project Case Study: White Bay Power Station – Roofing, Chimney Repairs and Hazardous Materials Remediation Work
Murphy Remedial Services Pty Ltd was engaged to perform the Roofing, Chimney Repairs and Hazardous Materials Remediation Work at White Bay Power Station, Project No. 110299. The client for the project was Sydney Harbour Foreshore Authority (SHFA). The site is a former coal fired power station that has been closed since the early 1980’s. The project works were undertaken to make selected buildings weather proof by replacing roofs, windows and downpipes. The chimney stabilisation cables were reconditioned and asbestos containing materials were removed from the ceilings in the former administration and staff amenities buildings.
The outline of the scope of works included:
- Site Establishment and sampling
- Early works: removal of asbestos ceilings in Administration Building, Switch House, Control Room and removal of contaminated dust.
- Replacement of asbestos ceilings in Entertainment Hall and Battery Room
- Repairs to the Boiler House North roof
- Repairs to the Boiler House South roof
- Repairs to Boilers House elevations – north, south including sheeting of windows
- Re-roofing of Turbine Hall, Pump House and repairs to elevations
- Re-roofing of Administration Building and repairs to elevations
- Re-roofing of Switch House South and repairs to elevations
- Repairs to roof membrane of Switch House North and repairs to elevations
- Repairs to Control Room roof and elevations (including Link Building)
- Cable and ladder repairs to North and South Chimneys
- Roofing repairs to Coal Handling Shed
- Roofing and metal repairs to Coal Conveyor and Transfer Shed
- Other repairs and miscellaneous work
- Site disestablishment and project handover
- Implementation of effective safety and environmental controls throughout the works
White Bay Power Station is of major significance in terms of heritage and the history of the area. The project was watched closely by the client, politicians and other major stakeholders. The prominent location of the site means that the project works will be visible to a huge number of people using the surrounding commuter routes on the Anzac Bridge and Victoria Road.
The building has heritage aspects and all works taking place had to be sympathetic to the appearance of the building. Consultation with the heritage architect enabled Murphy’s to select materials and techniques that would preserve the fabric and heritage features of the power station buildings.
The varied types of power station buildings required the provision of specialist access methods to carry out the works. Work was required on the two 80m tall chimneys, the 40m tall Boiler House, the main Turbine Hall roof and the smaller Switch House and Control Room buildings. For each structure a specific means of accessing works was adopted.
The environment of the site is contaminated by hazardous materials in many of the structures, due to the materials used during the construction of the power station and the process of power generation. Buildings contain asbestos materials, lead paint, contamination by lead and other metals.
Rolling scaffold access to the Turbine hall roofs
The re-roofing of the long Turbine Hall roof was made possible by building a rolling scaffold platform. This was designed and built by the specialist scaffolders of Murphy’s Access Solutions. The design was submitted to a specialist independent scaffold engineer who approved the concept and construction of the rolling scaffold. The provision of a safe work platform enabled the roofers to remove old roof sheets and lay safety mesh, while preventing falls through the open roof space.
Suspended scaffolding access for demolition of the boiler house concrete roof
The construction of the pitched boiler house roof involved the demolition and removal of a flat concrete roof at a height of over 40m from the boiler house floor. As there was nothing beneath the concrete slab, Murphy’s Access Solutions constructed a bespoke suspended scaffold system to provide a work platform for the breaking of the slab with jackhammers. A chute was built on the side of the Boiler House roof for the removal of concrete debris. This platform was then used for blasting and treating structural steel beams and the building of the new roof.
Removal of asbestos containing ceilings in the admin and switch house
Lifting capabilities for the project was provided by 80T and 150T cranes depending on the reach needed for the lift.
Chimney repair work
The two 80m tall chimneys were stabilised by guy cables. These cables were removed, reconditioned and replaced along with the connections at the base of the chimney. The replacement of the cables was carried out sequentially by rope access specialists and under the guidance and approval of engineers. Structural steel bracing inside the chimney was reconditioned and replaced.
Metal re-roofing work
Brand new metal roofs were installed on the Turbine Hall roof, the Turbine Hall lantern roof, the Pump House roof, the Switch house roof, the Control Room roof, the Link Building and the Boiler House South roof. All new roofing included the installation of insulation and safety wire mesh meeting the Australian Standard. Cappings and flashings completed the roofing work together with box gutter repair and replacement and new downpipe work. Work on the sloped coal conveyor structure was made possible with the installation of handrails by Murphy’s Access Solutions.
Structural steel and blasting works
Corroded steel in the Boiler House and in the Coal Handling Shed was abrasive blasted, treated and painted by specialist contractors. Work in the Coal Handling shed was carried out in hazardous materials PPE including disposable coveralls and masks, due to the lead contamination present in the building.
PROTECTION OF THE ENVIRONMENT
The former power station nature of the site meant that the working environment of the buildings was potentially contaminated with lead, asbestos and other hazardous materials. Before work commenced a NATA hygienist was employed to provide testing of suspected hazardous materials and monitoring of airborne contaminants. The hygienists’ recommendations were followed with regards to safe work methods, removal and disposal of all hazardous materials. Asbestos and lead containing waste was transported to an approved hazardous materials disposal facility and proof of environmentally responsible disposal was obtained. Clearance certificates were obtained following thorough inspection of removed asbestos materials by the hygienists.
Murphy’s operates a Quality Management System accredited to ISO 9001. Inspection and test plans were used throughout the project to track and monitor workmanship and key hold points requiring inspection by engineers or other specialists during the project.
Examples of hold points included:-
- Chimney cable removal and replacement
- Steel beam blasting and paint thickness
- Heritage roofing and other works
- Environmental clearance following removal of asbestos materials.
- Commissioning of suspended and rolling scaffold access
Benefits offered to Client during Project Works;
- Project work programmed to suit client’s requests
- Weekly project meetings with client throughout the project for communication and program updates.
- Preservation of heritage aspects of the building. Approval of proposed materials by the client’s heritage architect.
- Licenced removal of asbestos and hazardous materials discovered during the project.
- Delivery of the project with no lost time injuries, safety or environmental issues.
- Project delivered on-budget, on-time and with high quality workmanship.