I was doing some research on Derm's website and froun this...

I was doing some research on Derm's website and froun this little gem on BTEX

http://www.derm.qld.gov.au/environmental_management/coal-seam-gas/pdf/btex-report.pdf

It is quite laughable actually. It makes it clear that the main sources of exposure are driving your car, fumes at petrol stations etc.

How about this "Driving a motor vehicle one hour per day is estimated to add 40 µg of benzene to a person’s daily intake. Levels up to 10,000 µg/m 3(3,000 ppb) have been measured in air at petrol stations.

I think that the level erroneous at Cougar was less than 10 µg/m3. Which means that driving in your car for an hour would gives the same exposure as drinking 4000 litres of water. That is 6 years at 2 litres per day. Drive from Brisbane to Sydney and you have a lifetime exposure from drinking the water at Kingaroy.