Woodside Burrup Pty. Ltd. (Woodside) proposes to undertake a third monitor (M3) 4D marine seismic survey (MSS) as part of a reservoir management and surveillance program of the Pluto gas field which straddles the WA-34-L and WA-49-L permits The survey will acquire time lapse data that will be used to review subtle changes of fluid movement and gas pressure saturation in the gas reservoir, caused by hydrocarbons being depleted through production. To obtain these time lapse images, the seismic survey will follow as accurately as possible the sail lines acquired by previous monitor surveys (Pluto 4D Baseline and Monitor 1 in 2016 and Pluto Monitor 2 in 2020).

The Petroleum Activity will take place in Commonwealth waters within the North Carnarvon Basin, Exmouth Plateau, about 28 km north-west of the Montebello Islands and 150 km north-west of Dampier and is expected to take 40 days from late December 2026 to February 2027. The sound source will not be discharged during December to avoid the pygmy blue whales’ peak southern migration. In the event the Petroleum Activity does not occur during the target period, a contingency for the same period in the subsequent year (i.e. late December 2027 to February 2028) in included.

Activities proposed to be undertaken are as follows:
• 4D seismic data acquisition using a seismic survey vessel towing an acoustic source array and receiver cables (streamers).
• support operations from a support vessel and chase vessel.