CalEnergy, a subsidiary of Warren Buffett's Berkshire Hathaway Energy, owns a 100% interest in exploration permit EP408 which contains the Whicher Range gas field. 

The Whicher Range field, just south of Busselton, is estimated to contain as much as 4 trillion cubic feet in prospective resources. It was first discovered by Union Oil in 1968. 

CalEnergy had hoped to develop the resource as a conventional project and deliver 1 million cubic feet of gas per day as a pilot project. 

The pilot project would then be followed by a larger development campaign. 

Despite the prospectivity of the field, it was never developed as a conventional project. 

Research conducted by Curtin University in 2017 found the field would need at least 58 fracced wells to extract a commercial resource.

CalEnergy insisted at the time it could still be developed as a conventional resource. It undertook a phased appraisal and development campaign in 2013 with its joint venture partner GeoPetro Resources. 

Attempts to stimulate the reservoir encountered difficulties on each occasion, according to well reports from GeoPetro, which subsequently sold its interest and left the field. 

Earlier, operator Amity Oil had diesel-fracced the field to no avail. 

Whicher's geology is known for being a "tough nut to crack" and more than one company has failed in their efforts to commercialise it. 

This was only exacerbated when the McGowan government came to power and introduced a moratorium on fraccing across the state. 

The moratorium was lifted in a northern section of the state in 2018, but this obviously excluded the South West region. 

The Whicher Range-1 and Whicher Range-4 wells were decommissioned in 2019. The final step will be to rehabilitate forest vegetation at the well sites. The work will be conducted in the coming months.