Roy Hill Underground Services, Pilbara, Western Australia

Roy Hill Underground Services, Pilbara, Western Australia
  • Client: Decmil
  • Contract: value $2m

Project description

Decmil engaged Monford to deliver the underground services for the Roy Hill project in Western Australia’s Pilbara Region.

This included earthworks, service conduits, water services, electrical HV works, precast concrete pits and road lighting

Scope of work


  • Remove windrow/berm along road and cart to stockpile
  • Excavate 2.50m deep for underground service trenches
  • Excavate by hand to locate and expose services – as installed by separate contractors
  • Supply and install suitable bedding material obtained from commercial sources
  • Backfill conditioned material in trenches and compact in layers not exceeding 300mm thick
  • Cart excess material to site spoil
  • Cart away excess spoil
  • Directional drilling and install 100mm PE conduit under site HV road

Service Conduits – Electrical & Comms

  • Install 150mm HD PVC conduit
  • Install 80mm HD PVC conduits
  • Install 100mm HD OVC white communications conduits
  • Supply and install 50mm HD PVC white communications conduits to boom cates

Water services (SC&T to indication location)

  • Install 250mm HDPE potable water pipeline
  • Test and disinfect HDPE potable water line
  • Realign and replace storm water inlet pit in apron slab

Electrical HV works

  • Take delivery of HV cable and install part in conduit or direct buried trenche
  • Test cable upon receipt and hand over to the project principal
  • Install 150mm HD PVC conduit incl bends, elbows, etc
  • Install polymeric protection slabs to direct buried cable only

Precast concrete pits

  • Excavate to install pits • Install 900mm to 1200mm diameter pits, exceeding 1m deep internally
  • Install 900 to 1200mm diameter pits, not exceeding 2m deep internally
  • Install 1200mm diameter pits, not exceeding 2.5m deep internally
  • Core and stop pits and conduits as required, make good lifting holes, etc
  • Remove pit lids and adjust finish levels to FFL design
  • Remove communication cover on pits, replace with electrical pit cover, and vice versa

Road lighting

  • In-situ bases – 8m pole
  • In-situ bases – 12m pole
  • In-situ bases – 20m pole