I will explain for others, coal seams lay under impervious layers of sand stone. Fracking is used in approx 8 to 10 percent of wells. Depending on where. Where I work, we have the Walloon coal seam. The coal seam is loose, hence no fracking is done that I know of.
CSG is one of the most inspected and tested industries in Australia. We are constantly monitored by government departments. Our wells in world terms are second to none. We hardly ever have a methane leak and when we do, it's minimal. We have had multi millon dollar test equipment testing for gas leaks in the fields from time to time from 3rd party resources. And the test every single well for leaks.
The local feed lots have more methane coming out of the cows backsides .
The trouble is, other countries have CSG wells that leak like sieves and do cause environmental damage. Unfortunately movies are made and everybody thinks that all around the world it is the same.
Just to expand this further, methane does naturally leak from coal seams from shallow seams from time to time when the sandstone is fractured natually. The coal seam gas being under ground are held under pressure from water hence the coal seams are dewatered to make it easier to bring the gas to surface. The dept of coal seams vary from as a example 100 metres to over a 1000 metres deep.