INTRODUCTION

At a meeting of energy and mines ministers in Canada in 2013, it was noted that ‘the North American energy landscape is changing rapidly as technological innovation and increasing aff ordability of horizontal drilling and multistage fracturing technologies have unlocked vast unconventional ‘shale’ oil and gas resources’ and the importance of ‘building on and modernizing existing regulatory frameworks’ in the context of responsible shale oil and gas development. One year later the Council of Canadian Academies (CCA), an independent, not-for-profit organisation that ‘supports independent, authoritative, and evidence-based expert assessment that informs public policy’ released a report in 2014 on the environmental impacts of shale gas development prepared by a panel of multidisciplinary scientific experts. The experts concluded that in light of the uncertainty surrounding some environmental impacts from horizontal drilling and hydraulic fracturing, shale gas development needs to be supported by well-targeted science and management strategies to understand and mitigate potential impacts. The report also notes that Canada's regulatory framework for shale gas development is untested and there is uncertainty about the eff ectiveness of current provincial and federal regulations to mitigate all of the environmental impacts from shale gas development. In some states and provinces, governments have adopted moratoria on shale gas development while they study the potential health, safety and environmental impacts.

Regulators in both the US and Canada at the national, state and provincial levels are considering the potential impacts of shale gas development. In some jurisdictions regulators are modifying regulations created for conventional oil and gas operations, while in other jurisdictions regulators are preparing new guidelines and regulations to mitigate the environmental impacts particularly in the context of water protection. Landowner and environmental groups’ concerns about water contamination have prompted lawsuits in the US and Canada. Some contentious issues facing North American regulators include the potential impacts on water quality from shale gas development, the volume of water used in hydraulic fracturing and impacts on aquifers that are sources of potable water, well integrity, interwellbore communication, the volume of water used in hydraulic fracturing fluids, potential impacts of hydraulic fracturing on landowner water wells, demands for information from landowners and environmental non-governmental organisations (NGOs) about the chemicals in hydraulic fracturing fluids, fluid spills, the management and disposal of flowback fluids, and induced seismicity.