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Risks of Shale Gas exploitation in Europe
Context - As opportunities for exploitation of conventional resources of natural gas are becoming more limited, new sources of gas are being increasingly being mobilized in order to meet the demand.
One such important source is shale gas, which needs for extraction a process called « hydraulic fracturing », through which a presurized liquid in injected in the rockbed in order to create fissures and release the gas.
What are the potential health and environmental risks of hydraulic fracturing?
Why are unconventional natural gas resources in Europe likely to be exploited?
Exploration and production of natural gas and oil within Europe has in
the past been mainly focused on resources that can be exploited through
conventional boreholes. These resources are getting more and more
limited in the EU, and in order to meet demand, new sources are being
EU countries are now turning to exploring unconventional natural gas
resources, such as coalbed methane
and shale gas. In order to exploit
these resources, the rock layers need to be altered before the oil and
gas can flow. One of the techniques that can be used talter the rocks
is hydraulic fracturing, where pressurized liquid is injected in the
rocks in order to create fissures and release the gas and oil.
This technique hasn’t yet been used on a large scale in Europe, but
with a growing interest by many European countries to develop
shale gas extraction, the
European Commission has requested this assessment on the health and
environmental risks that could be associated with larger-scale use of
What potential risks were identified?
The potential sources of environmental and health risks that are
associated with hydraulic fracturing operations:
- The use of significant volumes of water and chemicals and
the lower yield of unconventional gas wells compared to conventional
- Ensuring the integrity of wells and other equipment
throughout and after the lifetime of the plant;
- The potential toxicity of chemical additives and the
challenge to develop greener alternatives; ensuring that spillages
of chemicals and waste waters with potential environmental
consequences are avoided ;
- Ensuring a correct identification and selection of
- The uncertainties associated with the long-term presence of
hydraulic fracturing fluid in the underground;
- The unavoidable traffic impacts;
- The potential for development over a wider area than is
typical of conventional gas fields;
- The emissions to the
atmosphere and noise
impacts related to plant and equipment during well construction and
The report identified a high risk for most of the environmental
aspects examined in the case of the cumulative impact of the
installation and exploitation of multiple wells. These include risks of
water contamination as well as release of contaminants in to the air and
in to the ground, and direct risks to
What is recommended to manage those risks?
Some measures can be taken to manage and reduce these risks:
- The development of less environmentally hazardous drilling and
- Development of better casing and cementing methods and
practices in order to increase well integrity;
- Development of a searchable European database of hydraulic
fracturing fluid composition;
- Research in to the risks and causes of
methane migration to
shale gas extraction;
- Development of a system of voluntary ecological initiatives
within sensitive habitats to mitigate future
The EU legislation als needs to be adjusted in order to sufficiently
address the risks and uncertainties associated with high volume
hydraulic fracturing (HVHF) projects.
These are highlights of the report " Support the identification of potential risks for the environment and human health arising from hydrocarbons operations involving hydraulic fracturing in Europe. Report for the European Commission" A report commissioned by DG Environment and produced by AEA Technology. Source document: AEA Technology (2012)