Some people have expressed concerns that shale gas development uses too much water and might affect the quality of water.
The AER works to ensure that all oil and gas development takes place in a manner that protects groundwater and surface water resources.
If addressed properly, there is very little risk to water quality. The following FAQs answer some of the concerns raised.
Question: How does the AER ensure that hydraulic fracturing does not lead to groundwater contamination?
Answer: Most horizontal, multistage fractured wellbores are hundreds or thousands of metres below usable groundwater aquifers. Any vertical fractures that occur as a result of hydraulic fracturing are generally in range from tens of metres up to (rarely) 200 metres, making it extremely unlikely that fractures could impact groundwater. For shallow hydraulic fracturing operations, the AER has strict requirements that limit the proximity to water wells, restrict the fracturing fluid volumes that can be used, and specify the use of only nontoxic fracturing fluids to ensure groundwater protection.
Question: I’ve heard of reports of water contamination due to inadequate well construction. Can that happen in Alberta?
Answer: The AER has very strict requirements for cemented casing (wellbore construction includes the use of steel casing that is cemented into the wellbore) in wells to provide a barrier between the wellbore and any nearby water sources (see Directive 008: Surface Casing Depth Requirements, Directive 009: Casing Cementing Minimum Requirements, and Directive 083: Hydraulic Fracturing – Subsurface Integrity).
Question: Hydraulic fracturing operations use water, but they also bring water from deep underground to the surface. In other jurisdictions, these fluids have been stored in open unlined pits or treated and reintroduced into waterways leading to contamination of water sources. Does this happen in Alberta?
Answer: The AER strictly forbids the use of unlined storage pits to store fluids produced from fracturing operations. Fluids that cannot be recycled or reused must be reinjected and stored in rock formations deep underground, far below groundwater sources.