POLITICIANS and community members lined up last week to criticise AGL's plans to use the controversial hydraulic fracturing (fracking) technique in its Camden operation.
The company had proposed to use a different technique to extract the gas but last week refused to rule out using fracking in the proposed northern expansion of the Camden Gas Project.
Fracking is used to stimulate the flow of coal seam gas from the coal by blasting in water, sand and chemicals, typically different types of surfactants.
Southern Cross University senior lecturer in the school of environment, science and engineering, Malcolm Clark, said there was no way to know how the rock would react when fracking was taking place.
"You don't know what the rock is like distal to where you are drilling and you don't know what weaknesses it may have," Dr Clark said.
Dr Clark said this uncertainty could mean that the process of fracking could open up other unknown faults in the earth, possibly releasing gases trapped in earth.
AGL had proposed using a horizontal drilling technique, which involves the drilling of a vertical shaft down to the coal seam and then drilling along the seam to stimulate the flow of gas instead of fracking.
An AGL spokesman said the company proposed to use horizontal drilling on wells in the northern expansion, but had included "a range of drilling, well stimulation and techniques" in their planning application to the NSW Planning Department.
"If any vertical well is drilled in the future, such a well will likely require fracture well stimulation to promote the flow of natural gas," the spokeswoman said.
The company will hold a community open day on February 1.
Scenic Hills Association spokeswoman Jacqui Kirkby said AGL had never ruled fracking out.
"We've looked at it really carefully and CSG mining is too experimental and there are too many things that could go wrong."
A spokeswoman for Resources Minister Chris Hartcher said the state government had not given AGL the green light to frack in the planned expansion and the company would need multi-agency approval to do so.
Campbelltown MP Bryan Doyle said he was opposed to fracking in the Camden Gas Project northern expansion.
"Fracking is a vital component to maximise their output so I always thought they might do it," he said. "I have concerns that that's not appropriate land use under a residential area, and I have concerns for the aquifers."
Macquarie Fields MP Andrew McDonald said the O'Farrell government needed to immediately ban fracking and stop the expansion of coal seam gas in south-western Sydney.
"I fear fracking near the Sydney water catchment and Campbelltown community will put public health and safety at risk for generations," he said.
Camden MP Chris Patterson said he was "bitterly disappointed" that AGL had gone back on its word not to use fracking. "What AGL and other companies need to understand is they are dealing with a real lack of confidence," he said.
Wollondilly MP Jai Rowell said he was against the use of fracking within the coal seam gas project.
"There is no denying that we need to meet the energy needs of the state however that should not be as a result of fracking around homes or in Sydney catchment areas in Wollondilly," he said.
"As a community we must actively seek out the facts about this proposal and pursue the right avenues to ensure we receive accurate advice and make our voices heard."
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