The Clash of Coal Seam Gas and the Great Artesian Basin

My step father told me about this issue today. The clash of economy and ecology. One has short term profit and the other millions of years to cumulate. I will be interested to learn the outcome.

http://www.abc.net.au/environment/articles/2011/03/22/3169602.htm

Coal seam gas extraction is the latest environmental battleground. Amidst the protests about land access, is the question of whether one of Australia’s geological and cultural icons is at risk.

ACROSS MOSTLY peaceful pastoral lands and farming communities some very clear and defined battle lines are being drawn. The nation’s vast stores of methane gas, locked up for millions of years in coal seams, are ripe for exploitation and major national and international companies are already moving in.

In the last six months, the Federal Government has approved three major coal seam gas (CSG) projects in Queensland worth $66 billion. Collectively and under myriad management rules and conditions set down by state and federal government, these three projects alone will drill more 18,000 wells in the coming decades. Overall, the state government expects between 25,000 and 35,000 wells to be drilled.

But environmental groups alongside some farmers and residents are staging blockades, locking gates and calling for moratoria on the entire industry. They say the coal seam gas industry is compromising prime agricultural lands and placing the rights of mining companies above all else.

However it may be Australia’s underground water reserves, ancient water held in rocks for millennia that cause a bigger headache for the gas companies. Australia’s famous Great Artesian Basin may be compromised by too many gas wells operating in the same area.
Extraction

To get to the coal seam gas, energy companies drill a well several hundred metres deep into the coal seam. The gas escapes back up the bore hole, along with differing quantities and qualities of the underground water. One project recently approved will extract, at its peak, 170 million litres of water per day.

Dr John Williams, a member of the influential Wentworth Group of Concerned Scientists and former head of CSIRO Land and Water, says the combined impacts of multiple major projects isn’t being addressed.

“Environmental impact statements (EIS) let you have death by a thousand cuts,” he says, referring to the lengthy documents which companies provide as part of their applications to governments. They are compiled by private consultants paid by the companies.

“The development of these resources needs to be seen as part of regional planning. At the moment we are letting one thing happen at a time.”

Dr Williams says existing knowledge about the Great Artesian Basin is not being brought together with the possible impacts of mining.

The Great Artesian Basin extends across nearly two million square kilometres covering parts of Queensland, the Northern Territory, South Australia and New South Wales. It comprises 22 per cent of the land in Australia. Due to a quirk of geology, the water held in the sponge-like rocks underground is under pressure. This means that when a bore is sunk, farmers often do not need a pump to bring water to the surface – it flows naturally.

The basin has allowed the expansion of grazing and cropping in regions of Australia that would otherwise not be viable. But the bores puncturing the groundwater reserves, known as aquifers, are taking their toll. Pressure has dropped in the basin to the point that one-third of previously free-flowing wells now must be pumped. To combat this, the wells are progressively being capped in a government-sponsored program.

There is also the question of recharge: water is being extracted from these reserves faster than it is replenished.

“The Great Artesian Basin has an important place in our culture and heritage,” says Dr Williams. “It allowed us to develop grazing and pastoral lands. It has an important history but it had been badly managed.

“We have moved on a bit now but just as we get it back under control we seem to be exposing it to risk.”
Incomplete knowledge

A central question not yet clearly answered is whether or not the process of drilling interferes with aquifers which are above or below the coal seams.

In September last year, a month before the Federal Government approved the first two projects, Geoscience Australia completed an analysis (pdf) of how the three projects would affect groundwater.

While some issues were manageable, Geoscience Australia said the “overriding issue in CSG development is the uncertainty surrounding the potential cumulative, regional scale impacts of multiple developments”.

“The information provided in the assessed EIS documents is not fully adequate for understanding the likely impacts of widespread CSG development across the Surat and Bowen Basins,” the report said, “nor will any level of information or modelling that can be provided by individual proponents.”

A separate report (pdf), which also relied on environmental impact statements, was commissioned by Federal Environment Minister Tony Burke’s department to look at potential impacts on surface and groundwater in the Murray Darling Basin. It raised the issue of surface subsidence which the industry had said would be “minor” as a result of drilling.

The report pointed out that “even small changes to the land surface due to subsidence may alter overland flow paths initiating new erosion features in susceptible areas.” Subsidence could also “change or cause fracturing in aquifers which may alter the hydraulic connectivity.”

Queensland Minister for Environment and Resource Management Kate Jones says the government is responding with an “LNG enforcement team” of 50 officers which will monitor data from 300 bores this year.

“This will enable us to validate and confirm the monitoring data supplied by CSG companies and determine whether company monitoring programmes are conducted appropriately. Their job is to make sure that the companies do the right thing in line with the new conditions.”

Companies would have to submit water management and monitoring plans to the federal government showing how impacts on water resources would be minimised.

Thresholds for pressure in aquifers would be set and monitored and companies must have plans to re-establish pressure if things went wrong.

Testing the waters

Critics have accused the Queensland and Federal Governments of granting approvals before enough is known about cumulative impacts. Already the CSG industry has drilled 3,000 wells in the state.

But Minister Jones says: “In areas where the impacts of different resource companies could overlap, a regional groundwater model is being developed to ensure the overall impact of all developments is taken into account.”

The Queensland Water Commission will develop the model, she says, and make recommendations to Government.

“The Government believes protection of the Great Artesian Basin is too important to leave to a piecemeal regulatory regime.”

In the meantime, the CSG companies are allowed to continue their work. One company says it will add $2 billion a year to the Queensland economy and create 9,000 jobs.

“The Queensland Government has adopted an adaptive management regime. This means that approvals can be modified to ensure the environment is protected if strict monitoring requirements detect any unexpected or unacceptable impacts.

Minister Jones says over the lifecycle of CSG, the fuel releases 50 per cent less emissions of greenhouse gases than coal. The gas, she says “is an important transitionary fuel as we move away from coal powered energy”.

Yet Queensland Government figures supplied to ABC Environment show that little of this gas will actually be used for energy in Australia. By 2014 when exports start, 80 per cent of all Queensland’s coal seam gas will be exported with no growth in domestic supply.

Fracking

Fracking Hydraulic fracturing, also known as fracking (or fraccing), is a technique employed at some (but not all) coal seam gas wells to increase the flow of gas. The Queensland Government says the CSG industry has advised that between 10 and 40 per cent of all wells will be fracked in the future. One report prepared for a CSG company says in some areas, as many as 70 per cent of wells will be fracked.

Water, sand and toxic chemicals are pumped into the coal seams at high pressure to widen the gaps between coal rocks and allow more gas to escape.

A fact sheet (pdf) on fracking, published by Queensland’s Department of Employment, Economic Development and Innovation says, fracking is “safe”, the risk of groundwater contamination is “minimal” and the chemicals used are “safe when used correctly”.

Dr Jim Underschultz, who leads research into technologies used in gas and geothermal industries at CSIRO, says there are two main concerns about fracking. “One is the actual fluid and what the chemical make up is and how much that might impact the [associated] water.”

One set of chemicals known as BTEX (benzene, toluene, ethylbenzene and xylene) have been banned in Queensland over safety concerns and NSW has indicated it will follow suit.

A second concern, Dr Underschultz says, depends on how well each well bore has been designed.

“There is a risk that when you induce a fracture, rather than it be contained within the coal zone it might extend into an aquifer above. If that’s the case, there’s a concern that the methane gas could leak into the overlying aquifer.”