URF: What are the Impacts on Water?
SOME PEOPLE HAVE EXPRESSED CONCERN THAT SHALE GAS DEVELOPMENT USES TOO MUCH WATER AND MAY AFFECT THE QUALITY OF WATER.
The ERCB 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. Some concerns raised include
Issue: Contamination of groundwater from hydraulic fracturing, which causes fractures or cracks large enough to allow fluid or gas to migrate into shallow groundwater.
ERCB Response: 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 the range of tens of metres and rarely up to 200 metres, making it extremely unlikely for fractures to impact groundwater. For shallow hydraulic fracturing operations, the ERCB has regulations that strictly limit the depth of shallow fracturing, distances to water wells, limit the fracture volumes that can be used and specify the use of nontoxic fracture fluids to ensure groundwater protection.
Issue: There has not been a documented case of direct contamination due to hydraulic fracturing in Alberta. However, there have been cases in other areas where there have been reports of water contamination due to inadequate well construction.
ERCB Response: The ERCB has very strict regulations 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 (Directive 008: Surface Casing Depth Requirements, Directive 009: Casing Cementing Minimum Requirements).
Issue: Hydraulic fracturing operations use water but also produce it; either water is produced from the fracturing process itself or reservoir water is produced along with the gas. In other jurisdictions, these fluids have been stored in open unlined pits or treated and reintroduced into waterways leading to contamination of water sources.
ERCB Response: The ERCB 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.
WATER QUANTITY – WATER VOLUMES USED IN HYDRAULIC FRACTURING
Issue: Although not all unconventional development uses a high volume of water, shale gas development can use significant volumes for the hydraulic fracturing process. Water that is used can be fresh water, recycled water, or nonpotable (salty) water from deeper geological formations. Concerns have been raised on how to ensure the responsible use of our water resources.
ERCB Response: Alberta Environment and Water (AEW) is responsible for the allocation of fresh water in Alberta and has comprehensive requirements governing the use of fresh water. While shale gas development using high water volumes has not yet occurred in Alberta, the ERCB is working with AEW on good water management practices. These practices will be designed to maximize water reuse (or recycling) and the use of saline or wastewater for operations. Fresh water use will be minimized to the greatest extent possible.