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.