Risk Assessment of Ship Collision on FSO Abherka and Oil Spill Modelling Due to Structural Damage

Floating storage and offloading (FSO) is an important vessel in offshore as shuttle storage of crude oil before it will transfer to the onshore facility located near the drilling platform. One of the locations that use FSO is Poleng Field in West Madura Offshore by operating FSO Abherka. Poleng field is supplying for two regions in Java and Kalimantan, it can affect the energy supply of the regions if there is an accident. The possible accident is a ship collision with FSO Abherka in addition the location is near Surabaya West Access Channel (SWAC). It is necessary to conduct a risk assessment of ship collisions on FSO Abherka and a consequences analysis of oil spills due to structural damage. Calculating ship collision frequency using CRASH method using two traffic scenarios found the result of ship collision frequency for external and internal powered collision: 4,20E-03 and 1,28E-03, and external and internal drifting collision: 4,51E-03 and 4,01E-03. Consequences of Collision simulation is conducted in three variations of collision scenario and impacting to the hull damage. Total asset & equipment loss due to collision in various degree of 30°, 60°, and 60° as follows: $23.462.196,03, $23.666.532,98, and $23.921.683,88. Those total asset & equipment loss and environmental impact from the oil spill is on the category of unacceptable. Applying a traffic monitoring system is effective to reduce the frequencies by about 71-93%.