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Hydraulic Fracturing and the Karoo

Company News Monday, March 11, 2013: Air Con-Nected Lubricants

South Africa has a great opportunity to secure a sustainable energy future, reducing the dependence on coal by using more environmentally friendly options available in this country, such as natural gas.

A plentiful supply of natural gas – the cleanest of all fossil fuels – may exist in parts of the shale rock formations deep beneath the surface of the South Western Karoo Basin. These can help secure South Africa’s energy future, but only if we can preserve the unique character of the area as well. Technology is playing a major role in Shell’s ability to unlock these supplies of natural gas, and contribute to secure that energy future.

Hydraulic fracturing

Hydraulic fracturing has been used safely for 60 years on 1.1 million wells. In the USA alone, hydraulic fracturing is used in around 35,000 wells a year. This widely-used technique involves the injection of water, sand and other fluids at very high pressure into the rock formation, creating tiny fissures allowing the natural gas to flow. The fluids injected into the rock consists of typically 99% water and sand, and around 1% chemical additives.

This technology, combined with horizontal drilling, has led to a rapid rise in the production of vast resources of natural gas trapped in densely packed rock, known as tight or unconventional gas. In the Karoo, natural gas is held in shale rock.

Decades of industry experience have led to the development of effective techniques for protecting groundwater supplies. The tight gas we produce typically lies over 1000 metres below underground fresh-water aquifers. Where we drill through acquifers to reach the shale, we prevent fracturing fluid from coming into contact with groundwater by casing wells with multiple steel and concrete barriers.

The U.S. Environmental Protection Agency has stated that there is no evidence of chemical contamination of water from fraccing chemicals.

And the U.S. organisation Environmental Defense Fund has stated; “If wells are constructed right and operated right, hydraulic fracturing will not cause a problem.” What’s more, the U.S. Environmental Protection Agency and the independent environmental experts, including the Ground Water Protection Council, describe fracturing as a safe and proven technique.

Safety Steps

Hydraulic fracturing technology has been continuously improved since it was first developed in the 1940s. Shell has made the process even more efficient by using advanced sensors to record what happens when we fracture the rock.

We use the latest seismic technology and software to map out fields below the surface to better target or fracturing. We fracture carefully in stages, locating the spots where tight gas will flow.

We have extensive experience with this technology, and we continue to follow strict measures to protect the environment, the surrounding areas, and local and regional water supplies.

Shell has applied to explore the area to find out if there are gas resources in the Karoo. If we are granted licenses, exploration would involve drilling up to 24 wells over three years. Any possible development is at least nine years away. That is how carefully we need to consider this.