FARMERS and activists want ironclad guarantees that unconventional gas exploration in the Otway Basin will not lead to contamination of aquifers underpinning agricultural production in the South East.
A 5657-square kilometre mining block in the Otway Basin closed for bidding in April, confirming the region's status as a key component in the State Government's Roadmap for Unconventional Gas in South Australia.
State Mineral Resources and Energy Minister Tom Koutsantonis says it is the second most prospective onshore gas province behind the Cooper Basin, where commercial shale gas is already in production.
It attracted two bids, while another 392km2 block in the Cooper Basin attracted three.
"SA attracted combined spending in mineral resource and petroleum exploration of more than $600m in 2012," Mr Koutsantonis said.
"Almost half of that total was spent on petroleum exploration in this State."
The new block in the Otway Basin included parts of Penola, Robe and Saint Clair rift troughs.
Duck Island Partners beef stud co-principal James Darling, Keith, said a precautionary approach needed to be taken to a new unconventional gas industry in the region.
"There have been major issues about exploration licences being granted over huge areas and renewed on no basis whatsoever in New South Wales, in particular," he said.
"There are issues of farmers' rights, issues of government carrying out their proper responsibilities and issues concerning groundwater contamination."
This included leakage from one aquifer to the next as a result of drilling and fracking, but it also included the chemicals being pumped down into the shales to release the gas, and how the used water was disposed of.
"All of these things amount to major concerns and I think the Lock the Gate alliance is actually advocating very well on behalf of rural Australia," Mr Darling said.
Lock the Gate formed in 2010 after New South Wales and Queensland communities became concerned about mining on good agricultural land and areas of fragile groundwater and environmental significance.
SA member Andrew Cooper says the State Government's roadmap is "frightening".
"It opens up, in my calculations, some 35pc of the State to PELs, a lot of them gas, in this clean, green age," he said.
"Mount Gambier relies on groundwater to drink, so it may be a bit of a problem down there."
There was little control over fracking water once it had been injected into the earth.
"No one has ever convinced me that they've got any control over where those fractures go, hence we get people in Queensland with filthy water because it cross- contaminates into the groundwater," Mr Cooper said.
"I'm not really anti-mining, but this destroys rural communities and prime farmland."
Existing Otway exploration licences already cover about 4416.9km2, including 3334.9km2 targeting shale gas and basin-centred gas.
They cover land surrounding Penola, north of Mount Gambier, east of Robe and above Port MacDonnell.
A Cooper Energy spokesperson said the Otway Basin had proven itself as a prospective site for conventional and shale gas.
"The Otway Basin has been the focus of exploration drilling by numerous exploration and production companies over the years, but Cooper has not conducted any hydraulic fracturing."
From the limited amount of drilling conducted so far, Cooper Energy estimated the potential gas within its acreage to be between 14 trillion cubic feet and 44tcf.
Department for Manufacturing, Innovation, Trade, Resources and Energy executive director Barry Goldstein said it was impossible for fracking fissures created to extract shale gas from 3000 metres to 4000m below the surface to reach all the way upwards into potable aquifers, which in the SE's gambier formation is at 500m.
"How much pressure do you think you'd need to exert to be able to lift 3km of rock?" he said.
"It's a physical impossibility and anyone who understands rock physics will know that.
"Unfortunately, rock physics is pretty boring to the general public."
Mr Goldstein said fissures extended from tens to hundreds of metres – not thousands.
Coonawarra vigneron Dennis Vice, Highbank Wines and Accommodation, says surveys have found linkages between different aquifers at different depths.
"That's a concern when you start looking for gas," he said.
"The extraction affects the pressures on the water table."
The groundwater system was extensive and stretched into Victoria and rigorous checks and balances were required.
"When we talk of scientists, there has to be transparency in terms of what information turns up so we can pursue all aspects of this issue together," Mr Vice said.
The Cooper Energy spokesperson said shale targets in the region were below 2500m and well-removed from aquifers, which were above 200m.
He could not offer a "meaningful comment" on the potential to negatively impact the water table height and groundwater pressure until there was a "sufficiently detailed proposal and impact analysis to discuss".
Beach Energy Investor Relations general manager Chris Jamieson said any fracture stimulation activities would be subject to a detailed Environmental Impact Report and Statement of Environmental Objectives first, "which would involve community consultation and ministerial approval."
*Full report in Stock Journal, June 13 issue, 2013.