• Australia
  • Oceania
  • Asia-Pacific
Case Study

Tailings Pipeline removal and replacement

Project Scope of Work

Amman Nusa Tenggara (AMNT), Batu Hijau, Indonesia disposes of tailing into Senunu canyon via a subsea HDPE pipeline. Tailings are conveyed offshore at Senunu Bay approximately 3.5km to a water to depth of 125m

The scope of work included Installation and stabilization of the replacement Western 44inch HDPE tailings pipeline (the “new pipeline”) and recovery of one existing (Western 44inch) HDPE pipeline (the “redundant pipeline”) that was comprised of the following main activities below:

1.Preconstruction ROV site survey

2.Removal of Debris and Stabilisation

3.Installation of HDPE Pipeline by Modified Bottom Tow method​

4.Stabilization of Offshore End of Tailings Line

5.Hydro-testing Support, Commissioning, and Handover​

6.Removal of redundant HDPE pipe (towed back to Benete Bay

Project Summary

 

 

 

The project was notable for a number of things. Firstly, the logistical administration to bring the Fire Opal into Indonesia which is under a cabotage regime. Secondly the  pre-project planning and engineering to execute a relatively new (to Shelf) subsea activity of pipeline bottom towing. Finally, the excellent performance of the Fire Opal with zero vessel downtime and  less than 0.005% down time due to ROVs, and a completely clean sheet for HSE incidents.