3. Environmental aspects

The economic production of unconventional gas has required the use of horizontal drilling and hydraulic fracturing techniques, as well as an increase in the number of wells.

It is this large number of wells that makes the environmental footprint larger than in the case of a conventional gas field. However, the use of well clusters (figure 5 ), which enable more than 15 wells to be drilled from a single drilling rig, significantly reduces the footprint of the installations.