Polluted ground water
ONE of the major concerns around fracking is the potential for the process to contaminate groundwater. Contamination can happen at many stages in the process and while best practice can reduce the risk of well failure, accidental spillage or negligence, it cannot eliminate the risk. Wells have failed and contamination has occurred in the United States rendering some drinking water sources unusable.
The cement casings used to line the bore holes that carry gas and contaminated water in and out of the well can corrode or fail resulting in the migration of contaminated waste water and/or methane gas into aquifers.
Gas and other substances can also migrate from the fractures underground and cause water sources to bubble with methane as we have seen in Queensland with the Condamine River, now described by locals as looking like “lemonade.”
Spillage of contaminated waste water and fracking fluid can happen at multiple stages in the fracking process including at the transport phase. Thousands of truck movements are required for each frack at each well to bring water, chemicals and waste in and out of the area. A single spill can contaminate surface water for decades.
The waste water ponds are lined with plastic and there are already cases documented in Australia where toxic fluid has leached from these ponds. The waste water ponds are also a risk in the case of a flood when the ponds could overflow and contaminate surface water.
In 2014 gas giant AGL’s pilot coal seam gas well at Gloucester in northern NSW was closed after banned chemicals were found in water samples.
With tens of thousands of frack wells potentially dotting the WA landscape in the next few decades, if the fracking inquiry finds in favour of the practice, there could be chance of a catastrophic failure and an irreversible contamination of our groundwater resources.
Volume of water used
The fracking process uses vast amounts of water. Each time a well is fracked it uses around 8 million litres of water, the equivalent of the daily water use of 65,000 people. The amount of water will vary depending on the geology but in general the water used per frack has increased over the past few years.
Wells are fracked multiple times and gasfields contain multiple wells so the amount of water used in the process quickly adds up. In drier areas like the WA Mid West this water use is of particular concern.
What to do with the water once it has been used to frack a well is another problem. Fracking fluid contains a toxic mix of chemicals and in addition when the water burps back up the pipe it can bring with it a cocktail of even more nasty chemicals and radioactive materials, heavy metals and salts from the water inside the broken rocks it has shattered. This makes fracking waste water a major problem for fracking companies.
Sometimes the water is reinjected deep underground but this also has its problems including that the water is taken out of the water cycle resulting in a permanent loss of that water from the system. Reinjection can also cause earth tremors and earthquakes. No one really knows the long-term impact of highly contaminated water reinjected back underground.
Often the waste water is left in ponds to evaporate or is released after into waterways after some “treatment” but this too has its problems including leaching of chemicals into surface water or shallow groundwater aquifers; poisoning of wildlife that is attracted to water sources; and soil contamination.