Ausgrid Marrickville


CLIENT: ENERGY AUSTRALIA

Project Case Study:

Metal Roof Replacement, Asbestos Ceiling Removal, Ceiling Replacement and Installation of Fire Retardant Panels

Marrickville Zone Substation – Meeks Road, Marrickville 

SCOPE OF WORK 

The works included:-

  • Construction of external scaffolding
  • Structural steel works
  • Construction of internal scaffolding protection work for switchgear
  • Construction and installation of louvres
  • The removal and replacement of metal roofing over the main substation building
  • Removal and replacement of the lower and handling bay roofs
  • The removal and disposal of asbestos ceiling panels from the interior of the building
  • Installation of Promatect fire retardant sheeting
  • Brickwork crack repair works

METHOD

External Scaffolding

Marrickville Zone Substation

The project required the replacement of the roof and internal works. External scaffolding was erected and certified by Murphy’s Energy Australia qualified scaffolders. The scaffolding erected externally acted as a work platform and fall protection for workers replacing the roof.

Internal Scaffolding

Specialist “bird-cage” scaffolding was required for interior works for this project. A galvanised tube and fit scaffolding system was necessary for the protection of internal switchgear. This allowed EA engineers access to the pull-out sections of the switch gear as the scaffold legs were able to be constructed around these areas, as the substation remained live throughout the work. Internal switch gear was screened during the erection of the scaffold to permit the scaffold crew to erect the scaffold safely. The internal scaffolding was lined with black plastic so that the protected switchgear was isolated from dust that would be created during the subsequent works carried out such as the replacement of the louvres.

Construction and installation of Louvres

This work was carried out internally in the substation building using the internal scaffolding protected by two-layers of black plastic. Because it was necessary to cut through 3 layers of bricks to fit the louvres, a large amount of dust would be produced. In addition to the black plastic on the “bird-cage” scaffolding, a bubble enclosure was constructed to contain the dust and prevent it reaching the working switchgear of the substation. As the cutting and installation work progressed, dust production was reduced by spraying water and using industrial grade vacuums.

The louvres for each opening were removed and replaced the same day to maintain the security of the building and keep it weatherproof.

Removal and Replacement of Main Substation Roof and of the lower and handling bay roofs and roof structure

The roof replacement works were completed in a manner which ensures the weatherproofing and security of the building was maintained at all times. All removed materials were reinstated on the same day. Staging and programming the works in this manner was a slow and tedious process for Murphy’s, but it ensured Energy Australia internal switchgear equipment was protected at all times and eliminated the risk of them being damaged. Murphy’s removed and reinstated the roof sheeting in 2.4m sections at a time in order to eliminate the risk of water ingress.

All materials were raised or lowered by scissor lift. Crane use was not an option as the site location was too close to Sydney international airport. Roof sheeting, timber purlins and top plates were removed. Existing steel rods in the brickwork were treated with Nitoprime Zincrich Epoxy. New purlins were bolted in place and Australian Standard Safety Mesh was laid. Fire protection boards were installed, Promatect H boards, top hat battens and Colorbond Klip-Lok roof sheeting laid.

The removal and disposal of asbestos ceiling panels from the interior of the building

Murphy’s organised NATA accredited hygienists for asbestos air monitoring and asbestos clearance certificates. The works area was isolated and signage erected to warn of asbestos removal in progress. Personnel removing the asbestos were required to wear correct PPE for asbestos removal, disposable coveralls, dust masks and disposable gloves, all of which were renewed each shift. The ceiling sheets were sprayed down with PVA glue before removing to minimise release of asbestos fibres and were then wrapped in two layers of black plastic and sealed with duct tape for disposal. The area was progressively decontaminated with a HEPA vacuum and PVA glue. After removal and decontamination, the area was reviewed by the NATA accredited hygienist and a clearance certificate issued.

All Asbestos removal works were monitored and executed in accordance with relevant legislation and Codes of Practice. Air-monitoring was established each day of the Asbestos removal and decontamination works, and we attained appropriate clearance certificates to verify compliant removal works.

Brickwork crack repair works

Murphy’s used the Helibar product and method to repair the brickwork in various areas throughout the substation. These brickwork repairs were completed alongside other project works so they could be programmed simultaneously with the controls for the other works in place.

Quality Management 

Marrickville Zone Substation

For all works on the project Murphy’s management developed Inspection Test Plans (ITP’s). These procedural documents were issued to and implemented by our site manager to ensure all works completed were in accordance with the project specification and relevant Australian Standards.

Project Control Group meetings were held throughout the project to keep open communication between Energy Australia and Murphy’s and the construction programme was updated progressively.

Safety Management

All Murphy’s project personnel were trained in the Energy Australia 3 day course for substation entry, electrical safety rules and CPR. All staff were trained in work activities through SWMS for all tasks and through specific safety training where required such as scaffolding, asbestos removal. Murphy’s Site Manager was the site first aider and Energy Australia had a Risk Management Technician monitoring the project throughout the works.

A Project Specific Management Plan was created and used to guide works for the project. Risk assessments before and during the project were conducted and used to formulate the Safe Work Method Statements which covered all high risk work on site.

All personnel undertook the Murphy’s Site Specific Induction before being allowed to start work on the project. The site was regularly inspected and audited to make sure the safety systems being used on site were effective.

Environmental Management

All waste produced on site was minimised and disposed of using a licensed environmental waste handler as appropriate. All staff were trained in environmental aspects of work during their Energy Australia training and Murphy’s Site Specific Induction.

Asbestos waste was double-wrapped in black plastic, sealed with duct tape and taken for legislatively compliant disposal at the asbestos waste disposal facility at SITA Kemps Creek.

Benefits offered to Client during Project Works;

–   Substation functioned as normal for Energy Australia through effective communication from Murphy’s both on and off-site

–   Substation was kept secure and watertight throughout the works

–   No OHS and/or Environmental issues due to good development and implementation of controls as outlined in the Project Safety Management Plan (PSMP)

–   Project delivered on-budget and on-time

Due to the high risks associated with the project – Working with Asbestos, Working at Heights, Working adjacent to a Transformer Yard and many more, Murphy’s assigned a highly trained and experienced team to the works.

Murphy’s project team all worked together to successfully deliver the project both on and off site. This included the development of all approved documentation and implementation at work-site level.

The project was delivered on time without any issues throughout the course of the works and Energy Australia was very pleased with the completed project.