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Working frack site raises new concerns about natural gas extraction

Posted by: Saving Water SA (Cape Town, South Africa) – partnered with Water Rhapsody conservation systems – 15 June 2011

By: Sarah Wild – guest of Royal Dutch Shell in Wyoming

Having seen a natural gas extraction facility that works — and, despite its problems, Shell’s onshore natural gas development in Pinedale, Wyoming, works — it is not certain whether natural gas extraction will be the holy grail of energy and the employment cash cow that SA expects it to be.

Wyoming’s Pinedale anticline raises new concerns about natural gas extraction

The country has been divided since it became public that Shell and several other energy companies had fixed their gaze on the Karoo and the shale gas reserves far beneath its surface.

Some have argued that it will solve SA’s energy crisis, ensuring a fuel supply for about 200 years; help the country move away from its dependence on coal; and create “unprecedented” employment.

According to the US Energy Information Administration, SA has technically recoverable shale gas resources of 13,7-trillion cubic metres, which could allow it to be energy independent.

The 1,1-trillion cubic metres of natural gas from the Pinedale Anticline can supply 10-million homes with electricity for more than 30 years.

Others have said natural gas would simply reinforce SA’s dependence on fossil fuels and cause irreparable environmental damage to an area with world- renowned biodiversity.

The Pinedale facility debunks a number of the myths but raises new concerns about natural gas extraction, including the contentious technique of hydraulic fracturing or “fracking”.

A natural gas well costs about $3m to drill and frack, depending on its depth. Perhaps the most important aspect of natural gas exploration is that the techniques used — from drilling to the composition of the chemicals — vary according to the geography, geology and temperature, among other variables, of the area. A well, which can be up to 2km deep, is drilled into the ground, with a mixture of diesel-based lubricants, biocides and water to reduce friction.

Most of the “flowback” — a fluid containing the drilling mixture, natural gas and solids — is regurgitated back into the drill hole. At Pinedale, this flowback is filtered and reused.

Once the well has been dug, cylinders with explosive charges are lowered into the hole. The charges are detonated, perforating the rock. Only then does the fracking occur. A water solution of fracking chemicals and sand is injected into the well under high pressure, making fissures in the rock about 3cm wide. Once again, flowback emerges from the well. Shell engineers say nearly all of this fluid is recovered over time.

Both of these processes — drilling and fracking — require fresh water. This is the first major, and possibly insurmountable, hurdle for natural gas exploration in SA. The Pinedale facility uses ground water for drilling. Although it is filtered after use, it cannot be recycled for drinking; it can only be reused in the drilling and fracking processes.

While the Pinedale area has about 1500 lakes as well as rivers running through it, the Karoo is semi-arid. In fact, SA as a whole is considered semi-arid, with its water resources under stress.

One fracking stage can use up to 20000 barrels of water — about 2,3-million litres — and a well can have up to 14 fracking stages, which could translate into 32-million litres of water. Moreover, in SA, Shell alone has applied to drill 24 wells, eight wells on three different sites.

That translates into a possible 772,8-million litres of water, about 300 Olympic swimming pools.

In Pinedale, Shell points out that 60% of the water it uses is recycled from previously used fluid. However, natural gas development has been taking place in Pinedale for more than 60 years, with Shell occupying rigs for more than 10 years.

There is well-developed infrastructure — kilometres of piping, water treatment facilities — that allows it to recycle its water, as well as economies of scale that make it feasible.

SA does not have this, and, yes, it would be able to build it up over time, but the country does not have the water to waste.

The first step in natural gas development is exploring for the gas, which requires the wells to be drilled. This means that the water used in these initial stages — the millions of litres of water — would not be salvageable.

Perhaps the largest myth surrounding natural gas exploration in SA is that it would be an engine of job creation.

Shell’s Pinedale facility, which houses 425 wells, has a staff of 66. Most of its work — drilling, fracking, water filtering — is outsourced to specialist companies. SA, which does not have a natural gas industry, would have to bring in foreign skills .

There is the possibility of secondary job creation, but that would start to gain traction only after the initial exploration phase, which takes about three years. However, those jobs may come at the expense of other s as it may not be possible for agriculture and tourism — the revenue generators in the Eastern Cape — and mining to co-exist. But that would become apparent only after production had begun.

As would be the unintended consequences of natural gas development. Citizens in Pinedale have experienced spiking ozone levels as a direct result of natural gas development. These cause respiratory problems in children and the elderly. An engineer on the Pinedale site said the problem could not have been foreseen since it was unique to the area.

This raises the question: if the techniques and chemicals used in natural gas exploration vary according to location, is it possible to rule out that exploration on each new site could result in unexpected and possibly fatal consequences?

However, since natural gas exploration has been taking place in the US for decades, it is fairly well regulated. The federal government employs two staff members who take readings daily from different locations around the anticline, monitoring fugitive gas emissions and water quality.

The question then is whether SA has the capacity to monitor natural gas exploration with the vigilance it requires.

Even before that, SA needs regulation to govern the exploration and development of these resources. Then the country can decide whether Shell and the other hopeful companies meet the necessary criteria — rather than the other way round.

Natural gas exploration works in some places, but it is uncertain — given the lack of a natural gas industry, water scarcity and the absence of regulation — whether it will work here.

Source: Business Day

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