Prelude FLNG; Source: Shell

Shell awaits green light for work on gas project off Australia

Shell Australia, a subsidiary of oil major Shell, has submitted an environment plan (EP) to the country’s offshore regulator for the installation of the drilling template on the Crux natural gas field off the coast of Western Australia.

Prelude FLNG; Source: Shell

The National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) confirmed that Shell submitted the environment plan on 13 July 2023, proposing to undertake the installation of the Crux drilling template within production licence AC/L10.

The drilling template is a prefabricated steel structure with a seabed footprint of approximately 266 m3, which will be lowered onto the seabed by a light construction vessel. The purpose of the drilling template is to act as a guide for the subsequent Crux development drilling campaign.

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This EP covers the vessel-based installation of the drilling template and associated activities along with the operation of remotely operated vehicles to aid the drilling template installation and positioning on the seabed. Currently, the drilling template installation is slated to take place between 1 September 2023 and 1 April 2024. This campaign is nominally scheduled to occur over a one-month period subject to acceptable weather and subsurface conditions.

After the drilling template installation activities start, complete installation of the drilling template should take approximately 24 hours. In a bid to account for potential shifts in schedule, the environmental assessment is not seasonally specific and assumes the activities described in this EP may occur at any time during the life of the EP.

The current Crux development drilling EP, which includes a five-year duration, will retain the installation, inspection, and maintenance of the drilling template as part of its activity description to ensure the drilling template structure has an in-force EP for the activity beyond the installation campaign.

The Shell-operated Crux development, which was sanctioned in May 2022, is located in Commonwealth waters in the northern Browse Basin, 190 kilometres offshore northwest Australia and 620 km northeast of Broome, in approximately 165 metres of water depth.

The project is being progressed by the Crux joint venture which comprises Shell Australia as the operator and SGH Energy as its joint venture partner. The first environmental approval for Crux was the Crux Offshore Project Proposal (OPP), which was accepted in August 2020 by NOPSEMA.

According to Shell, the Crux gas field has been identified as a source of backfill gas to the existing Prelude Floating Liquefied Natural Gas (FLNG) facility. As a result, Crux will have the capacity to supply the Prelude FLNG facility with up to 550 million standard cubic feet of gas per day (mmscfd).

The development of this project will consist of a platform operated remotely from Prelude while five wells are expected to be drilled initially. Moreover, an export pipeline will connect the platform to Prelude, which is around 160 kilometres southwest of Crux. Shell anticipates the first gas in 2027.