Monday 5 December 2016

ONE OF THE PROBLEMS WITH GAS-MINING EMISSIONS


Australia could be underestimating its annual greenhouse gas emissions by an amount equivalent to the output of the nation's entire transport sector”. This was the startling finding released last month by the Melbourne Energy Institute.

According to the report, Australia's carbon accounting problem stems from a failure to include the fugitive emissions released during the production phase of unconventional gas, i.e. gas extracted from coal seams, shale and sandstone. Currently the level of fugitive emissions is set at only 0.1% of production; in other words the authorities are conveniently ignoring them. The authors point out that this level, is in stark contrast to measurements made at US unconventional gas fields, where measured leakage rates have been found to be as high as 17% of production, 170 times higher than Australia's assumed figure.

Hydraulic fracturing, or “fracking”, is a process used to blast apart underground rock seams to release the methane, which is lighter than air and a highly potent greenhouse gas. Therefore it stands to reason that when those rock seams are shattered, not all the gas will conveniently flow into the pipes for capture, but will seep upwards through the fractured rocks to the ground's surface and into the atmosphere.

In south-east Queensland, residents living inside gas fields are reporting a range of health problems which are consistent with the inhalation of methane. The occurrence of fugitive methane in the air was supported when, some three years ago, methane was found bubbling freely up through the Condamine River, and further confirmed by Southern Cross University Researchers who recorded methane levels within the gas fields many times higher than elsewhere.

Any claim that the industry didn't know this would occur should be summarily dismissed. Any engineer would have known the risks, they simply ignored them as an expedient measure to support their grab for riches, and it's still being ignored.

This poses a serious problem for the government which has committed to the Paris agreement calling for emissions reduction because, with every new well drilled, the problem worsens, and those leaks continue for ever, even after extraction ceases and the wells are capped.

- John Edwards

This article was originally published in the VOICES FOR THE EARTH column in The Daily Examiner on November 14, 2016