How does drilling for shale gas affect groundwater?
Shale gas deposits are typically 3-4km below ground, while freshwater aquifers are usually about 300m below the surface. (International Gas Union).
Shale gas deposits are separated from the fresh water aquifers by extensive layers of impermeable geological formations. These layers form efficient natural barriers between fresh water and gas resources.
Shale gas wells have several layers of steel casing and cement that form a continuous protective barrier between the well and the rock. Millions of oil and gas wells have been drilled through aquifers without causing problems. (See: International Gas Union, Shale gas – the facts about environmental concerns.)
Regulators require monitoring and management conditions appropriate to each site during and after production. This includes monitoring the levels and quality of local groundwater.