St Joseph’s College, Hunters Hill, appointed FDC to deliver an upgrade of the existing swimming pool precinct, with Perfect Contracting awarded the demolition and civil works package in early 2021.
The project involved demolition of the existing swimming pool and associated enabling works to facilitate construction of a new Olympic class facility. The original pool measured approximately 30 by 25 metres and 2.7 metres deep at the deep end. It comprised a 300 millimetre thick reinforced concrete floor and 250 millimetre thick reinforced concrete walls.
Demolition & Asbestos Removal Works
Demolition was carried out using a fleet of 20 tonne plus excavators fitted with hydraulic breakers. Due to the size and reinforcement of the structure, the works required a controlled demolition sequence and sustained heavy breaking to reduce the pool shell to manageable rubble. Approximately 4,000 tonnes of masonry was demolished, processed and stockpiled within one week.
Material was removed from site using two 8 wheel hook trucks and one 10 wheeler tipper, with haulage averaging approximately 190 tonnes per day to a recycling facility at Camellia. Backloaded road base was returned to site for use in temporary roads and walkways. All vehicle movements across the school grounds were tightly controlled, with each entering vehicle escorted to maintain site safety. The works were completed with zero incidents.
In parallel with the demolition works, approximately 500 tonnes of asbestos contaminated soil was removed from the eastern end of the site. The contaminated material was excavated, managed and disposed of in accordance with EPA requirements, with spoil transported to a licensed facility at Eastern Creek.
Civil Construction Works
Following completion of demolition and bulk removal, the project transitioned to civil works to support the new facility. The redevelopment included construction preparation for a new underfloor pump room, a new poolside amenities building with change rooms, and associated service installations.
To accommodate new plumbing and electrical services, sandstone cutting was undertaken using a 750 millimetre rock saw mounted to a 5 tonne excavator. The cutting works enabled precise trenching and service corridors within the constrained site environment. Sandstone recovered during these works was retained by the school for future use.
Bulk excavation then proceeded to achieve the revised design levels. The excavation encountered virgin soil, substantial sandstone seams and evidence of previous excavation and construction activity. Continuous attachment changes between buckets and rippers were required to maintain progress and ensure segregation of VENM and GSW materials. Due to limited working space, stockpiles could not remain in fixed positions and were relocated repeatedly throughout the programme, with some materials moved approximately 20 times before final export.
As excavation progressed, piling works were undertaken at the western end of the pool, including installation of sixty 600 millimetre diameter piles to a depth of 2.0 metres. Load out operations continued using a fleet of subcontracted 10 wheeler tippers together with in house haulage, with material transported off site as clean fill to construction projects across greater Sydney. Achieving the required excavation depth and profile took approximately eight weeks due to variable ground conditions and the constraints of the live site environment.
The project was also affected by a two week COVID lockdown delay. Once work resumed, the predominantly plant based nature of the remaining activities enabled the site to continue operating under the required restrictions, with additional controls implemented to maintain compliance.
The final stage of the works involved detailed trim of the pool excavation. The sandstone substrate and irregular seam profile required careful trimming to achieve final design levels. Final trim was completed using a 24 tonne excavator supported by a 5 tonne excavator, achieving a finished surface within 10 millimetres of final level across the entire pool. This exceeded the specified tolerance of 20 millimetres. A temporary VENM ramp was then used to track plant out of the excavation before being removed during the final day of load out.
Perfect Contracting completed the demolition, hazmat, excavation and civil works package at St Joseph’s College safely and to specification, delivering a technically complex package within an operational school environment.
We Get It Done.
By Daniel Green
Perfect Contracting acknowledges the Aboriginal and Torres Strait Isander people as Traditional Custodians of the country on which we live and work. We pay our respects to the Traditional Custodians and Elders past, present and future, and honour their connection to the land and ongoing contribution to society.