Producing energy from any source gives rise to environmental risks, and extracting shale gas is under consideration as a future method in the UK. Based on experience from the USA and stringent UK regulations, the BSIF Liquid Pollution Control Group makes recommendations for tackling spills control when extracting shale gas.
Rising living standards and increasing use of personal computers, smart phones and tablets all mean energy consumption in the UK continues to rise. Conservation of energy through smart meters, improved fuel efficiency, and home insulation has had great effect in modifying demand, and such measures will continue to limit energy consumption, but they will not stop it increasing.
At the moment UK energy supplies are provided by natural gas (40%), coal (10%), nuclear power (25%), biomass (12%) and renewables (12%). With climate change targets, the closure of coal mines, concerns surrounding nuclear power and the high cost of renewables, Britain needs additional diverse sources of energy.
Enormous effort is going into new technology such as clean gas power stations, thermo-voltaic light, new battery developments and seismic surveying, which will alter the relative attractions of nuclear, gas, and renewable sources, but predicting which technology will meet the increased demand at a sensible cost with acceptable carbon emissions is difficult. No single source will supply all our requirements, and cost is important: 4 million households in the UK live in fuel poverty, and the UK’s current energy costs are some of the highest in the world.
One option under consideration is the extraction of shale gas. It is argued that the cost of British shale gas would be low because:
a) There are huge volumes.
b) It is relatively easy to extract.
c) It is an effective way of reducing carbon emissions compared to other sources.
d) The cost of distribution is low as the gas infrastructure is already in place.
But a new industry would bring its own set of requirements on pollution control to avoid environmental spills. All energy sources, gas, coal, nuclear, biomass, and renewables carry environmental risks. Environmental concerns around shale gas focus on:
a) Although carbon emissions are lower, they may still not reach required levels.
b) Heavy traffic in locations close to residential areas.
c) Earthquake risk.
d) Contamination of ground water.
Setting up a drilling site would need heavy equipment, sand and other inputs, causing initial disruption, and the drilling typically takes several weeks, but then gas production would go on for decades with few lorry movements. However, a major concern is the heavy goods vehicle transportation of the large volumes of flowback water created, and the BSIF Liquid Pollution Control Group agrees with leading shale gas companies that the water should be processed on site.
Contamination of groundwater is a risk, but a peer reviewed study of contamination of groundwater
by Duke University (The Effects of Shale Gas Exploration and Hydraulic Fracturing on the Quality of
Water Resources in the United States by Avner Vengosh et al) found fracking has not contaminated
ground water. However the study did find that accidental spills of fracking waste water could be
dangerous to surface water in the area. This could become a risk to groundwater through seepage
into the ground if there is no liner across the site. Both surface water and groundwater should be
adequately protected, but groundwater is especially challenging and more costly to remediate once
pollution has occurred.
The most authoritative recent report on experience from the USA by the Environmental Protection
Agency (https://cfpub.epa.gov/ncea/hfstudy/recordisplay.cfm?deid=332990) found scientific
evidence that hydraulic fracturing activities can impact drinking water resources under some
circumstances. The report identifies certain conditions under which impacts from hydraulic
fracturing activities can be more frequent or severe:
Water withdrawals for hydraulic fracturing in times or areas of low water availability,
particularly in areas with limited or declining groundwater resources;
Spills during the handling of hydraulic fracturing fluids and chemicals or produced water that
result in large volumes or high concentrations of chemicals reaching groundwater resources;
Injection of hydraulic fracturing fluids into wells with inadequate mechanical integrity,
allowing gases or liquids to move to groundwater resources;
Injection of hydraulic fracturing fluids directly into groundwater resources;
Discharge of inadequately treated hydraulic fracturing wastewater to surface water;
Disposal or storage of hydraulic fracturing wastewater in unlined pits resulting in
contamination of groundwater resources.
Some extraction activities are quoted as giving rise to environmental issues, when in fact they have
already been addressed in the UK in regulations:
Injection of hydraulic fracturing fluids directly into groundwater resources: Not allowed in the UK
Discharge of inadequately treated fracturing wastewater to surface water: Not allowed in the UK
Disposal or storage of hydraulic fracturing wastewater in unlined pits: Not allowed in the UK
If extraction of shale gas is given the go-ahead in Britain, the BSIF Liquid Pollution Control Group
makes the following recommendations:
Flowback water from fracking should be treated on or near site to minimize vehicle
movements and the associated disruption.
Spill control measures will be site specific but they should reflect:
The requirements of the Environment Agency’s Onshore Oil & Gas Sector Guidance
Version 1, 17 August 2016
Relevant recommendations from CIRIA 736 Containment systems for the prevention
Best available technologies developed for shale gas sites, especially from the USA
Spill awareness and response training should be provided by accredited organisations to all site
operators. The BSIF is working with UKOOG (UK Onshore Oil and Gas) to promote accredited
training and spread of best practice.