BAM Ritchies

Case Study: Pluto LNG Project

Client: Woodside Burrup Pty Ltd

Main Contractor: Van Oord/BAM Ritchies jv

Location: Dampier, Australia

Date: 2008

As part of the Pluto LNG Project, BAM Ritchies undertook blasting to create a new berth pocket within an operational supply base and a trench for an underwater trunkline shore crossing.

The berth pocket was blasted to eight metres below datum, the area involving 6107m2 with some 7752m3 blasted, plus a quay-wall sheet-pile trench 126m long, 3m wide and down to 13.5m below datum. Additionally a 5m wide trench was blasted for a trunkline shore crossing within a narrow window of opportunity during spring tides.

Blasting was undertaken with 17,650kg of Orica’s Powergel Buster, using three different diameters of cartridges to ensure the design criteria were met. Non-electric Exel Enduradets and surface Connectadets allowed controlled blasting and single hole initiation to meet the strict restriction for ground vibration and water borne pressure waves.

On completion, no high spots were found or any other remedial work was required.

Very strict environmental controls were adhered to so that there were no oil spills or damage to marine life (especially dolphins and turtles).

The barge used was van Oord’s self elevating platform BHD Supply using three legs and six anchors. Drilling was carried out with two rigs over a 'moon pool' utilising down-the-hole hammers with 115mm drill bit diameters and overburden casings having a diameter of 152.4mm.