Your source states that 4 pilot wells have been drilled in the area.
How can you be certain that the casings on these have not been badly constructed allowing methane to migrate up from deep shale layers to near the surface?
You and I can only go on what the company states and that is that tests on the wells show that they are intact and no gas is/was being produced from or around them.
They have to make a legal statement to the regulatory body that this is so - and so far that regulatory body has not contradicted their statement.
ETA : Source of the above is from an
Origin ASX (Australian Stock Exchange) statement. Not a good idea to lie in them.
Is there any way of telling the difference between gas from sub-surface layers and gas from deep layers?
Not if the gas is from the same formation. If the gas's source are different coal seams/formations it may be possible to differentiate between the sources by analysing the gas's make up. Google "hydrocarbon fingerprinting".
Unless there was very careful monitoring of the gas seepage into the river before the wells were drilled, how does anyone know that there hasn't been a significant increase ?
Why do you unskeptically accept the reassurances of the drilling companies?
Not unsceptically, but their anecdotal "evidence" is that locals have reported these types of leaks for the past 30+ years.
About as valid an anecdote as the YouTube video that has no provenance at all.
Oh, and those wells in the area were not fracced. This would be a matter of record with the regulatory body as well.
Why do you characterise those concerned citizens who critisize fracking as delibertately misinforming scare mongers?
I only criticise those that deliberately misinform as scare mongers.
Without provenance, I could speculate that the YouTuber knew of the history of gas releasing into the Condamine River (if it is true) and has taken advantage of the current scaremongering about fraccing to put up an unsubstantiated claim that this is caused by CSG drilling.
btw 2 quotes from Brisbane Times article,
The bubbling in the Condamine River near Chinchilla was most likely naturally occurring coal seam methane and not linked to coal seam gas mining, Queensland Natural Resources Minister Andrew Cripps said today.
"Speculation about the actual cause of bubbling gas in the Condamine River based on limited information is unhelpful and irresponsible and does not contribute to informed commentary on this industry," he said
So speculation is irresponsible unless of course you are a politician speculating that it's most likely not linked to coal seem gas mining
What speculation?
He repeated what Origin told him after they said they tested the well for gas leaks and that these pilot wells never produced gas.
He was commenting on the speculation by anti-CSG groups.....
Let's look at that.
Earlier in the day, NSW Greens MP Jeremy Buckingham has seized upon the video, claiming it as proof the industry is unsafe in a statement released this morning.
"Gas bubbling up through a 5km stretch of the Condamine River is the worst case recorded so far of what appears to be pollution related to fracking for coal seam gas," Mr Buckingham said.
These were pilot wells that
were never fracced and never produced gas.
This answers your previous question regarding my gripe about misinformation.
Here is a prime example of a "concerned citizen" bandwagonning on the fraccing debate and scaremongering by spreading misinformation.