Risk Analysis Of The Proposed Hides LNG Pipeline, Papua New Guinea

J.C. Braybrooke and M. Broise

This paper discusses the results of desk and field investigations undertaken for a risk analysis of the proposed Hides- Wewak LNG Gas Pipeline project in Papua New Guinea (PNG);

The proposed project would have entailed construction of approximately 410km of a 660mm diameter (26-inch) gas pipeline from Tagari to Dallman Harbour near Wewak, and a 90 km oil pipeline from Tagari to the Kutubu Central Production Facility.

The project life was to have been fifty years and hence the risk analysis had to assess the hazards in terms of their probability of occurrence within that time frame. Due to the proposed limited storage capacity at Dalman Harbour very long return period events (say 1 in 5000 years or a probability of occurrence of 0.01 in the lifetime of the pipeline) were considered important. For planning purposes pipeline outage periods of greater than about three days were considered unacceptable. From overseas experience with pipeline breaks this was judged to be equivalent to either the loss of tens to hundreds of metres of pipeline or to multiple pipeline breaks occurring during a single event. Events which could produce such losses were deemed to be project ‘no go’ events.

The investigation was a concept level review of the proposed pipeline alignment to assess the vulnerability of the pipeline to regional geohazards.