Geotechnical investigtion and designs, Boral Peppertree Quarry, NSW, Australia
Boral’s largest hard rock quarry development in Australia, the Boral Peppertree Quarry is in Marulan South, in the NSW Southern Tablelands region.
PSM was engaged to complete geotechnical investigations and prepare designs and specifications for the plant site, the rail embankment, a water storage dam and associated spillway feeding into twin 4 m diameter corrugated steel pipes through the rail embankment. PSM was also asked to maintain a geotechnical site presence during construction.
engineering AND technical opportunities
Keeping costs down and minimising rehandling of material were key considerations of this project. Engineering and technical opportunities included:
- Construction of a 20 m high rail embankment, a 114 ML dam, 100 m long twin 4 m diameter corrugated steel pipes spillway, the quarry plant platform, and the noise bunds with material won from site borrow pits
- Enough characterisation of existing ground conditions to allow planning and costing of construction activities.
approach and innovationS
Following a rigorous assessment and modelling, PSM’s tailored approach included:
- Targeted borehole and test pit investigation to supplement geological model of site
- Characterisation of subsurface conditions in a way that allowed contractors to understand how the material would behave once excavated
- Preparation of design using available site materials
- Education of the client regarding costs and risks associated with various levels of material rehandling.
As the principal consultant, PSM planned and executed a targeted geotechnical site investigation at a reduced cost. An experienced contractor successfully implemented the design within the expected timeframe and with no ongoing contract claims at completion of the works. PSM’s presence on site during construction allowed the design to be optimised and was certified completed in accordance with the design.