Sunday, December 09, 2012

Fracking Gas

More than 20,000 square kilometres (7800 square miles), A quarter of Scotland, covering the entire central belt and a part of the southwest, have been earmarked by the UK Government for possible exploitation by controversial technologies such as fracking to extract gas from wells dug deep into the ground. Scotland is rich in coalbed methane gas because of its coal reserves. Plans are afoot to drill 22 wells to tap the methane gas in coal seams near Falkirk and Stirling. Some 16 exploratory wells have been dug.

One recent study published in an international scientific journal found that 632 chemicals were used to extract underground gas in the US. Of the 353 on which there was detailed information, more than three-quarters were potentially hazardous to health, with over one-third being gender-benders (chemicals that can disrupt sexuality) and one-quarter capable of causing cancer. "These results indicate many chemicals used during the fracturing and drilling stages may have long-term health effects that are not immediately expressed," concluded the researchers from The Endocrine Disruption Exchange in Paonia, Colorado.

 Scottish Environment Protection Agency (Sepa) warns that fracking for gas is "very likely" to bring radioactive wastes to the surface in fluids. The radioactivity is naturally present in the ground, but is released by the process. Sepa also points out that, in addition to the climate pollution caused by burning the gas, there could be accidental emissions. Releasing methane, a much more potent greenhouse gas than carbon, would help accelerate global warming, it says. Mary Church, a spokesperson for Friends of the Earth said  "Communities around the world are seeing the devastating impacts of coalbed methane and shale gas expansion. We need to learn from these experiences and ensure the same doesn't happen here."

The UK Government suspended fracking after it was blamed for causing small earthquakes near Blackpool last year, though it is now expected to give it the go-ahead.

1: Fracking, hydraulic or ballistic: This frees the gas by deliberately fracturing the rock by drilling down and then pumping in high-pressure liquids, or even detonating explosive charges. Fracking can be used to extract the gas from shale, a type of rock, or to free "tight gas" held in deeper, denser rock formations. It can also be used to help mine the methane that inhabits coal seams.

2: Tapping "coalbed methane": This involves drilling into and along the seams, and then pumping out and disposing of large quantities of water, a process known as dewatering. The removal of water may be enough to stimulate the flow of gas, though sometimes fracking may also be necessary.

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