McDermott wraps up first subsea campaign for Santos

McDermott International has completed a subsea campaign at the Bayu-Undan infill well Phase 3C project in the Timor Sea under its first subsea engineering, procurement, construction and installation (EPCI) contract with Santos.

McDermott’s scope included a tieback of a single in-field well to existing facilities, re-using existing flexible flowline, with a new umbilical and certain infrastructure.

Work commenced in May and concluded in December 2021.

In line with McDermott and Santos’ sustainability goals, local Timor-Leste businesses were engaged to execute components of the project, including concrete mattress manufacture, marine training and experience onboard the primary installation vessel, the Lay Vessel 108.

According to McDermott, a key to the execution was the recovery of existing flexible flowlines, flushing to clear hydrocarbons, re-laying and a tieback from a new in-field well to the existing Bayu-Undan facility.

Recovery and reusing existing flexible flowlines was a significant factor in enabling the work to be completed nine months from award and within the project schedule, the company added.

Said to be one of Timor-Leste’s largest gas fields, Bayu-Undan is located approximately 500 kilometers off the northwest coast of Darwin, Australia, and 200 kilometers off the southeast coast of Timor-Leste.

The project comprises three production wells and will develop additional natural gas and liquids reserves, extending field life as well as production from the offshore facilities and the Darwin LNG plant.

The field was discovered in 1995 and commercial production began in April 2004, delivering 115,000 bpd of condensates and LPG.

Production from the Phase 3C infill drilling program started at the end of July 2021, followed by Santos’ announcement that the outcome from the first well was better than anticipated.

The Australian energy giant signed a Memorandum of Understanding (MOU) with the Timor-Leste regulator Autoridade Nacional do Petróleo e Minerais (ANPM) in September last year to progress carbon capture and storage (CCS) at the Bayu-Undan field.

The proposed CCS project entered into the front-end engineering and design (FEED) phase just a few days ago.