Beharra Springs-4 is being drilled to investigate a reservoir interpreted as being separate from the gas field of the same name.
Operator Origin Energy Developments on Friday said the activity was drilling ahead in 8 1/2-inch hole at 2630m.
It will be drilled to the planned intermediate total depth at 3240m measured depth in the Kockatea Shale.
It will primarily target the Late Permian Wagina Sandstone, the main producing reservoir in the Beharra Springs, Beharra North and Tarantula gas fields.
The Century-18 rig will drill the well vertically, after which a coil tubing unit will drill the remaining section of the well to a planned total depth of 3374m in May.
Beharra Springs-4 is 2km north of the Beharra Springs gas plant, 30km southeast of the township of Dongara.
Origin holds a 67% interest in the well, while Arc owns the remaining 33%.
