Australian regulator accepts Beach Energy’s plan for Trefoil seabed assessment

Australia’s National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) has approved Beach Energy’s plan for a geophysical and geotechnical seabed assessment on the Trefoil field offshore Australia.

According to NOPSEMA, Beach Energy submitted the plan on 25 February 2020. It was approved on Wednesday, 29 April.

In the plan, Beach Energy proposed to undertake a geophysical and geotechnical seabed assessment within the Rockhopper (T/RL3), Trefoil (T/RL2), and Yolla (T/L1) permits and open acreage within the Bass Strait.

The seabed assessment operational area is approximately 126 kilometres from the coast of Victoria and 94 kilometres from Tasmania.

The seabed assessment consists of surveys which will evaluate the potential development of the Trefoil and Rockhopper fields and is required to determine the placement of a rig for the future drilling of a well within the Trefoil field and for surveying a potential pipeline tieback route to the Yolla platform.

The geophysical and geotechnical surveys will potentially be undertaken separately and take up to 25 and 55 days, respectively, between April 2020 and 31 December 2021. Timings of the surveys are contingent on the availability of suitable vessels, weather, and the receipt of required environmental approvals.

NOPSEMA said that the seabed assessment consists of a geophysical survey which will collect bathymetry data and detect seabed hazards. The survey will be done using a multibeam echo sounder, side-scan sonar, sub-bottom profiler, and a magnetometer.

The geotechnical survey will collect information on the properties of the seabed and the underlying shallow sediments by borehole sampling, core sampling, and performing a piezo cone penetrometer test.

The seabed assessment area will cover a 6×6 kilometre area over the proposed well location and a 1×40 kilometre corridor from the proposed well location to the Yolla platform and will cover a total area of 68.32 square kilometres.

As the well location has not yet been finalised the seabed assessment area will be within the operational area which covers 552 square kilometres.