Australia’s National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA) has approved Beach Energy’s plan for geophysical and geotechnical seabed assessment on the Trefoil field.
The assessment includes geophysical and geotechnical surveys within the Trefoil (T/RL2) and Yolla (T/L1) permits and along a future pipeline route in Commonwealth water open acreage in the Bass Strait.
The sites are located approximately 126 kilometers from Wonthaggi, Victoria, and 94 kilometers from Stanley, Tasmania.
The surveys are required to assess seabed properties for the potential development of the Trefoil gas field.
This environment plan allows for surveys to be undertaken either separately or together any time between December 2021 and 31 December 2023. Exact timing is subject to the availability of suitable vessels, weather, and the receipt of required environmental approvals.
The geophysical survey could take up to 25 days to complete and will include a multibeam echo sounder, side-scan sonar, sub-bottom profiler and magnetometer.
The geotechnical survey could take up to 30 days and will include borehole sampling, core sampling, piezo cone penetrometer test, and visual observations by drop/towed camera.
According to NOPSEMA, Beach Energy submitted the plan on 12 October and it was approved on 3 December.
The potential Trefoil project is a subsea development at the Trefoil field , with a tie-back to the Yolla offshore platform.
The Trefoil gas field is located 38 kilometers east of the Yolla platform. The development of the Trefoil resources through the existing Yolla platform would extend the asset life by approximately 10 years, increase recovery from the Yolla field and defer abandonment of the Yolla platform and Lang Lang Gas Plant.