The Coal Seam Gas (or Coal Bed Methane) industry, and the mining industry, present the greatest threats to the GAB today. These industries use enormous quantities of this good potable and finite GAB water, and turn it to “waste water” – which then becomes a problem to get rid of, as it pollutes the environment with millions of tonnes of salt, contaminated with heavy metals and other pollutants.
For CSG extraction, the water must be removed from the coal seam, to extract the gas. Not only does CSG extraction require a lot of water to start the extraction process, but the aquifer itself must be de-watered to lower the pressure to allow the gas to escape. The volume of water to be removed from the aquifers is staggering – the latest figures are that the equivalent of twenty times Sydney Harbour (10 million megalitres) will be extracted from the GAB for CSG.
To date, over $500 million has been spent by governments and bore owners in trying to slow the depletion of the GAB and to restore its diminishing pressure. CSG extraction does the exact opposite of what GABSI has been trying to achieve. GABSI is trying to conserve the GAB and restore pressure; CSG extraction de-waters and de-pressurises the GAB, to extract the gas.
The CSG industry is ‘young’ in Australia, but because the govt’s are getting such huge amounts of money from it, the industry is booming at an unbelievable pace. We should be able to learn from the mistakes the U.S. has made, where CSG mining (they call it “natural gas” in the U.S.) has been going on for twenty years. There it has drained the aquifers, and caused incredible environmental damage, pollution and underground fracturing, methane migration, and enormous health problems – and the issue is actually now before Congress as they belatedly try to tighten up their Safe Drinking Water act.
To extract the gas from the coal seam, they use a process of injecting water, sand and a supposedly “trade secret” mix of chemicals into the rock strata, under great pressure, to crack the rock along its horizontal strata, in order to release the gas trapped within the rock layers (this is known as the Halliburton method).
As that process occurs, some of the fluids used escape rapidly, and appear as “spills” on the surface, and around drilling rigs; some stay in the groundwater; some “migrate” along the various cracked strata, and contaminate the groundwater or rivers further “down gradient”. Some of these ‘fracking fluids’ contain volatile chemicals, others are known to be toxic, and carcinogenic. Many of these ‘secret’ chemicals are now known, as a result of “leaks” and traces identified in groundwater studies (initially in America – as their csg industry has been going for a long time, and the disastrous consequences are now all too evident).
Information obtained from environmental clean-up sites shows that known toxins are routinely being used, including hydrochloric acid, diesel fuel (which contains benzene, toluene, and xylene) as well as formaldehyde, polyacrylamides, and chromates. These chemicals include known carcinogens and other hazardous substances, and are being used here in Australia.
This industry is ‘self-regulated’ - and so a system of constant and random inspections by an independent body, should be immediately introduced. No other industry, that has the potential to have such an enormous detrimental impact on the environment – and on our vital, life-giving water – is allowed to conduct their business without stringent inspections.