THE Rev Dr John Cameron (Letters, October 10) is much too complacent about the dangers of the highly dubious method of shale gas extraction termed fracking. From his comments, the evidence suggests that he is failing to keep in touch with the findings of peer-reviewed science.

It is today quite undeniable that dwindling fossil fuel reserves are not a problem either for Scotland or the world. There is plenty to warm the planet into an irretrievable death spiral. So, why is anyone searching for new sources of fossil fuels? If we are to preserve an ecologically healthy planet, the science is unanimously saying that it will be necessary, in 20 to 30 years, for mankind to have abandoned fossil fuels in favour of renewable energy. In these circumstances, support for any proposal that the UK should resort to extracting shale gas, by sanctioning fracking, is simply inexplicable. However, it will not happen for several reasons.

The residents of northern England are well aware of the earth tremors which accompanied fracking tests near Blackpool, and will be wary of fracking in their neighbourhoods, and so they should be. Recent research, reported in a geological sciences journal, points to direct links between fracking in the United States and a magnitude 5.7 earthquake in the near vicinity of well activity. This is not an insignificant event.

They should also be concerned that extensive testing near shale gas extraction wells, in the US, has discovered that ground water pollution has occurred within a one mile radius of the well head for nearly all wells tested. This is further compounded by the detection, by satellite, of abnormal methane leakage into the atmosphere, from the vicinity of the majority of fracking installations. Methane is a powerful greenhouse gas.

Furthermore, a new study from the Johns Hopkins Bloomberg School of Public Health has linked hydraulic fracturing to premature births and high-risk pregnancies. Pre-term births were 40 percent higher among women who lived in areas of intense drilling and fracking operations, and the pregnancies of these women were 30 percent more likely to be considered “high-risk,” according to the study. Again these are not insignificant statistics.

In the US some of these disadvantages of fracking can be tolerated because the wells exist in the vast expanses of meagrely populated prairie. Nevertheless recent reports suggest that even the gung-ho Americans are beginning to question this technology. In crowded Britain the technology has little chance of securing public acceptance.

Alan J Sangster,

37 Craigmount Terrace, Edinburgh.

IN reply to the Rev Dr John Cameron, my concern over fracking (Letters, October 9) concerned water wastage and proven leakage.

Dr Cameron cites one million wells sunk in the last 50 years. The New York Department of Environmental Conservation estimates that each well needs between 2.4 and 7.8 million gallons of water over its life time - with growing populations and regular droughts, can any country countenance such waste? New York has now banned fracking.

He also states that steel and concrete linings fully seal all wells and there has never been a single leak. Really? In the mid-west states of America, many wells suffer repeated leaks caused by ground movement brought on by other wells nearby and by fractures in the thin and brittle concrete. Poor operating practices, brought on by the inevitable cost-cutting as fuel prices fall, don't help matters. These well documented leaks cause methane contamination of domestic water supplies and natural water courses.

As always the clarion cry for fracking is cheap fuel for the masses. Without water there will be no masses.

John Elder,

14/8 Howden Hall Road, Edinburgh.