First Re Purpose Platform through Decommissioning Activity
Authors: Mohd Kamil Muhammad Beheshti 
Published: November 2020

The objective of this paper is to share about the most recent decommissioning project in Malaysia which is Ophir Field Abandonment activity. Interesting facts about this project is most of the petroleum facilities are recovered and repurpose to re-use for other Field Development project. Upon successful abandonment of the field by August 2019, the wet tow transportation activity of the Wellhead Platform had been the 1st of such activity in Malaysia, as well as the 1st offshore platform to be repurpose through decommissioning activity.

Ophir field is a small production field located 210km North East of offshore Terengganu. Ophir development plan was installation of standalone-suction pile Wellhead Platform structure with few development wells. The oil is transported via means of flexible flowline into a Floating Production Storage & Offloading (FPSO) for processing prior to lifting for market needs. Such standalone-suction pile Wellhead Platform structure was the 1st installed in Malaysia.

As Ophir operator monetizing the hydrocarbon, the field experienced several reservoir issues. Further technical assessment and economic scenarios were exhaustively evaluated. As a result of the exhaustive evaluation, the field had received Cease of Production certificate by PETRONAS to proceed with abandonment activity.

Per PETRONAS Procedure & Guideline for Upstream Facilities (PPGUA) requirement, Ophir Abandonment Plan is reviewed and deliberated in 3 stages gated decommissioning review process known as Abandonment Review (AR). The stages review consists of abandonment project planning, Decommissioning Option Assessment and Decommissioning Project Execution.

Decommissioning of upstream facility is a niche subject in Malaysia, thus educating various internal and external stakeholders were required in order to establish the key steps for the decommissioning execution. Liaison with related state agencies was done through Zone Economic Exclusive sitting, with Petroleum Safety Unit's (PSU) as the secretariat. PSU is one of the unit under Ministry of Domestic Trade, Cooperative and Consumerism (MDTCC) who is responsible in coordinating the policies, licensing, regulations and activities related to the safety of petroleum, petrochemical and gas industry in Malaysia.

Ophir Abandonment project is uniquely interesting because most of the petroleum facilities and accessories such as flexible flowline, Wellhead Platform, FPSO mooring lines and anchors had been recovered, transported and repurpose for a new Field Development project. The Wellhead Platform weighted around 900 MT was removed via single lift method and wet towed 100 km to the new field and such wet tow activity is the first of its kind in Malaysia. Various engineering and structure simulation were conducted to ensure the abandonment activity scheduled in August 2019 executed smoothly without any HSE incident and impact to the environment.

There were few great experiences and important lessons that PETRONAS had learned from this project. PETRONAS believes that the culture of sharing experiences and lesson learnt will be the epitome for each operators & contractors to work safely, stimulate creativity and strive towards decommissioning cost compression for every decommissioning project.