KILOMETRES under France lies a reserve of gas that could provide energy for the country for the next 30 years... but it is desperately difficult to extract and getting it out could pollute the country's water sources for the rest of time.
Although shale gas has been known about for years, it has always been problematic and prohibitively expensive to extract.
Unlike North Sea gas, which is found in large open-pored sedimentary rock reservoirs, the shale gas under France is found in impermeable shale formations between one and three kilometres deep, just below the freshwater aquifers.
No exploratory drilling has yet been done, so the reserves are only theoretical, but there are thought to be shale gas reservoirs running from the Pas-de-Calais down to the Ile-de-France, and across the south of France from the Dordogne to Savoie, taking in the Tarn-et- Garonne, Tarn, Lot, Aveyron, Hérault, Cantal, Lozère, Gard, Ardèche, Drôme and Vaucluse.
There could be enough gas to supply France for 30 years, but cracking open the shale formations could allow toxic water to pollute the aquifers. In addition, shale gas wells have lower productivity than conventional wells and production falls off very quickly, meaning dozens – if not hundreds – of wells would be needed.
With oil prices soaring owing to demand from the Far East, it may be a resource that could slash France's energy bill. Some predictions say there is four times more shale gas than natural gas in the world and it is now a major part of US gas production, rising from one per cent of production in 2000 to 12 per cent now.
Shale gas formed when muddy deposits of rotting vegetation were laid down up to 300 million years ago. The mud became compacted and buried deep within the Earth, and the organic material decomposed into hydrocarbons under the pressure and heat.
Exploration teams have to drill vertically and then horizontally to reach the shale gas reservoirs. There they use a technique developed in the US known as hydraulic fracturing – hydrofracking – which is akin to setting off a series of explosions to open up the rock and let the gas gather so that it can be piped to the surface.
Millions of litres of water are forced into the well under huge pressure, along with tonnes of sand and chemicals to prop open the fractures, and to keep the water liquid and let the gas flow.
However, studies have blamed the drilling process for large-scale water and air pollution and high levels of radioactivity in waste water from the drilling. The process was highlighted in the Oscar-nominated film Gasland, which showed inflammable gas in tapwater.
In March 2010, the then ecology minister, Jean-Louis Borloo, agreed permits for drilling in the east and south of France, prompting a wave of protests from concerned citizens and elected officials.
Ministers have now belatedly reacted to their complaints. Prime Minister François Fillon has ordered a halt to drilling until the middle of June when two reports on the environmental and economic effects of the exploration are examined.
"He said: "Exploration work for shale oil and Exploration work for shale gas has sparked legitimate questions from populations living near the sites."
His move came after the ecology minister, Nathalie Kosciusko-Morizet, met with a barrage of protest when she arrived in Sarlat in the Dordogne.
President Sarkozy avoided a similar protest on a visit to Lauzerte in the Tarn-et-Garonne to talk to dairy farmers; roads up to the bastide town were closed off and protestors from Non au Gaz de Schiste kept out.
Towns and villages across the affected regions have held public meetings, with some, such as one in Cazals in the Lot, being bilingual. A major event is planned for Cahors on April 17.
Websites in English have also been set up, including www.SchisteHappens.com, which is leading protests in the English-speaking community, along with Belinda Berry's www.noshalegas.wordpress.com. A petition has so far attract- ed 82,000 signatures.
Ms Berry, who lives near Montcuq in the Lot, said she set up the website to gather useful information and rational arguments so that people could know the implications.
"As well as contamination of drinking water, there is also the sheer ugliness of having several boreholes in an area, the heavy lorries on the roads and the dangers of having hundreds of litres of dirty and polluted water lying around.
"Oil and gas companies are very aggressive and I am worried that, once they get a foothold in the area, they will be very difficult to stop."
Sarlat Green councillor Frédéric Inizan echoed her fears, saying: "We don't trust the government. We are not reassured and believe the interests of big business will be put before ecological and health issues.
"The minister says the American system won't be used here, but as far as we know, nobody has come up with an alternative. We will do everything we can to keep the pressure up."
Another Sarlat councillor, Jean-Fred Droin, said: "In the Dordogne, 46 per cent of our economy comes from tourism and that would be destroyed if there was drilling in the area."
"We have to make economic choices and we should stick with tourism. It would also be a disaster for our children if we left them with a polluted water table."
Oil firm had started 'fracking' near Paris
OIL EXPLORATION firm Vermilion Energy was set to carry out the first commercial tests of horizontal hydrofracking in France just 60km east of Paris when ecology minister Nathalie Kosciusko-Morizet called a halt to "unconventional drilling".
The company, France's largest top oil pro- ducer at 8,501 barrels a day, drilled three exploration wells in the Lias shale underlying the Ile-de-France last year and used "fracking" technology in two of them to test for oil recovery.
Both are now producing nominal quantities of oil and Vermilion was about to start a large-scale operation when the minister called her moratorium.
Another company, Toréador Resources, had been planning to start drilling three exploratory wells at its Château Thierry site outside Paris.
