In the North-west Marine Region (NWMR) offshore from Western Australia (WA), the geophysical company Spectrum Geo Pty Ltd (Spectrum) proposes to acquire multi-client marine seismic surveys (MSS) within the Greater Exmouth operational area. The Greater Exmouth operational area comprises of an area of approximately 105,600 square kilometres (km2) of Australian Commonwealth waters. The Greater Exmouth MSS may be acquired as a single survey, or as separate surveys (not concurrently) depending on weather, vessel availability and regulatory and operator financial approvals. At the closest point, the southern boundary of the operational area is ~ 67 km from the nearest land (Hermite Island) and ~ 124 km from the mainland coastline (Dampier town). South of the operational area are the Montebello Islands Commonwealth marine reserve boundary (~28 km away) and Barrow Island marine management area (~80 km away). The northeast corner of the operational area overlaps with the multiple use zone of the Argo-Rowley Terrace CMR and is ~50 km to the boundary of the Argo-Rowley Terrace CMR Marine Park zone (IUCN zone II). The Greater Exmouth operational area excludes WA State waters. Water depths throughout the operational area range from 33–3,300 m, and seismic activities will not occur in water shallower than 100 m, or within 12 km of the Glomar shoals. Operational DetailsIn terms of technical methods and procedures, the proposed MSS will be similar to others conducted in Australian marine waters. No unique or unusual equipment or operations are proposed. The proposed MSS will be undertaken using a purpose-built, seismic survey vessel. During the proposed activities, the survey vessel will traverse a series of pre-determined sail lines within the operational area at a speed of approximately 8–9 km/hour. The operating pressure for the acoustic source will be approximately 2,000 psi with a maximum volume of 4,350 cubic inches.Timing of the ActivityThe Greater Exmouth EP is designed for a duration of three years. The timing of commencement and duration of individual surveys have not yet been determined, but the first survey (once the EP is accepted) will not occur before Q4 2017. The MSS activity will also not occur during peak pygmy blue whale migration periods. Furthermore, the commencement of each survey will be dependent on fair sea state conditions suitable for marine seismic acquisition, vessel(s) availability, client data schedule requirements and granting of approvals from the appropriate government bodies.