FIRST ON 7 | Residents in Sydney's south-west say recent flooding has exposed a bubbling coal seam gas leak.
Campbelltown Council and the Environment Protection Agency (EPA) have both launched investigations following concerns from locals that recent flooding has exposed a leak at Menangle Park.
But gas company, AGL, says the bubbles are just air, and are not harmful.
In a statement, AGL said comprehensive testing techniques have already proven that the wells are secure and pose no threat to the community.
"These are just air bubbles that have been trapped beneath the earth's surface - this happens quite commonly," AGL spokesperson Karen Winsbury said.
But local Greens MPs disagree.
"The drilling pits I saw a couple of months ago just over here are now under water and whatever was in those drilling pits has now gone into the Nepean River," claimed Greens MP Max Phillips.
Greens colleague Jeremy Buckingham echoed those sentiments, claiming AGL is an 'arrogant' company.
"They are poisoning the Nepean-Hawkesbury river system," Mr Buckingham said.
Residents like the Scenic Hills Association's Jacqui Kirkby say the EPA's investigation is just for show.
"At the moment we're still waiting for their judgement on AGL's constant breaches of air monitoring on the Camden gas project," Ms Kirkby said.
In a statement, Campbelltown Mayor Sue Dobson said the risk was considered during the approval of the well last year.
"Inundation of the well was a distinct possibility and would be of concern should it occur," Mayor Dobson said.
While AGL says bubbling is common after a long dry spell locals are far from convinced.