Traditionally, CSG wells are drilled straight down. These are called vertical wells. Where conditions allow, we can use ‘deviated’ wells instead. These are wells that are drilled at angles away from vertical.
We use them in two major ways:
- in the Bowen Basin, with its deeper, less-porous, thick coal seams, we deviate the well bore until it runs horizontally along the target coal seam.
- in the Surat Basin, on intensively farmed land, we group multiple wells on single, larger pad. From the surface, the bores slant away at around 70 degrees to intersect multiple, thin coal seams.
Deviated drilling lets us reach the same amount of gas underground from a much smaller area on the surface – very important for reducing our impacts on high-production farmland.