About one quarter of all Canadians rely on groundwater for all their daily water needs, so it’s vitally important that groundwater is protected during oil and gas operations. Concerns are often raised about hydraulic fracturing’s effects on groundwater. However, more than 175,000 wells have been hydraulically fractured in Western Canada over the past 60 years with no evidence of drinking water contamination, according to regulators in BC and Alberta.
The oil and gas industry protects groundwater in a number of ways, but the most effective protection comes from solid well construction. Isolating the groundwater from the wellbore is critical. Here’s how that happens.
Every well begins with a surface hole, drilled to the base of groundwater protection. Then two or more layers of cement and steel casing (see image at right) are used to create a solid barrier between the well and any underground fresh water resources. Only when the steel and cement barrier is in place does drilling continue to the targeted reservoir.
Hydraulic fracturing is only conducted at safe distances from fresh water aquifers. In fact, the resource (oil or gas) is typically beneath 2,000 to 4,000 metres of solid rock, several hundred metres below the deepest fresh water aquifers.
Further, innovative technologies ensure that the fissures created by hydraulic fracturing extend only 50 to 100 metres from the wellbore and are contained within the source rock.
Groundwater is also protected with the use of safe – and often benign – fracturing fluids, as well as recycling, treatment and safe disposal of any water use in oil and gas activities. These industry procedures, combined with government regulations, help ensure that groundwater is safeguarded for the millions of Canadians who rely on it every day.