Australian offshore regulator, the National Offshore Petroleum Safety & Environmental Management Authority (Nopsema), is evaluating the environmental plan for Inpex’s proposed subsea expansion of its Ichthys liquefied natural gas project.

Inpex is proposing to install subsea umbilicals, risers and flowlines (Surf) infrastructure associated with the next stage of the Ichthys LNG project.

The subsea production system will be expanded through the installation of a new gathering system and new infrastructure required to connect new production wells to the existing gathering systems on Block WA-50-L off Western Australia.

According the environment plan, the proposed activities will be undertaken over five years. The offshore work is expected to start in the first quarter of 2021 although “the exact timing for commencement and completion will be dependent upon approvals, vessel availability, operational efficiencies and weather conditions”.

The coronavirus and the latest oil price crash could too impact the schedule. Less than a week after Inpex filed its environmental plan the company announced it was reviewing its investment plans group-wide and pursuing further cost reduction measures because of the economic uncertainty.

The scope of work outlined in the Ichthys expansion environmental plan, which Inpex submitted to the regulator on 19 March, includes survey activities; installation, mechanical completion and commissioning of the Surf infrastructure; and commissioning of the wellhead Xmas trees at drill centres.

All subsea activities will involve remotely operated underwater vehicles (ROVs) with on-board cameras to monitor and perform the installation activities

Nopsema will also look at the potential environmental impact of equipment transfers, refuelling and crew transfers.

A joint venture of US contractors McDermott International and Baker Hughes is working on the large subsea contract for the offshore expansion of the Ichthys field.

Offshore installation will begin in 2020 and will be completed in 2023, using state-of-the-art assets including McDermott's derrick lay vessel DLV 2000.

The Ichthys joint venture comprises Inpex on 66.245%, Total with 26% and Japanese LNG customers having 7.755%