Help by Learning About CSG

Drilling rig near Miles, Queensland

I recently drove to Chinchilla in Queensland to find out about the effects of coal seam gas mining on a small country town since production began in 2006. I met Karen Auty, a resident of the town, who knows many people in the area who live on lifestyle blocks, productive farming land and in the town.

I interviewed Karen and am posting her comments along with my observations and research in a series of blogs on CSG education, before and after a gas boom, roads and litter, noise and air pollution, and health impacts, including mental health.

When CSG mining companies first came to Chinchilla no one questioned them as natural gas had been extracted at nearby Roma for sixty years without problems. (See blog 1/5/2015 Roma Oil & Gas.)

‘Australians need to get educated,’ said Karen. ‘They need to learn what CSG is and learn the difference between LPG and natural gas, and between conventional and unconventional gas.’

Check out the Elgas LPG Gas blog for the difference between LPG and natural gas. http://www.elgas.com.au/blog/486-comparison-lpg-natural-gas-propane-butane-methane-lng-cng

At Roma, conventional gas was extracted from sandstone above the Great Artesian Basin. This natural gas, which may have migrated from another strata, perhaps coal, is found in layers of sandstone, trapped by an impermeable ‘cap’ rock. Drilling through the ‘cap’ rock allows the gas to flow out naturally. Legislation ensured that exploration companies compensated for any damage to real improvements on properties. If the drillers didn’t find gas, they often found water and the farmer had a free bore. Conventional gas extraction requires less wells and infrastructure than unconventional gas.

Coal seam gas is an unconventional gas as it has a completely different recovery process. It is found in coal seams above and below the Great Artesian Basin. If the gas is below the Basin, drillers penetrate the impermeable strata underlying the Basin then drill into the coal seams below. Salty water has to be extracted from the coal seam before the gas will flow. Drilling may release into the water other toxic chemicals, found naturally in the coal seams. Fracking is used to increase the flow if the gas will not flow naturally and may also release chemicals. During the fracking process, chemicals, sand and water are blasted into the well to fracture the coal seam.

Gas and water are piped to large central processing plants where they are separated. The gas is then piped to market and large amounts of salty water, often containing toxic chemicals, is piped to huge plastic lined dams. This water is treated in massive reverse osmosis (RO) plants designed to remove the salts and chemicals. The energy for this massive infrastructure may come from a company’s gas-fired power station.

The treated water, sometimes called ‘beneficial water’ is then disposed of. It is used by industry; it supplements town water supplies and creeks; it waters gravel roads for dust suppression; and irrigates stock feed crops and planted native hardwood forests. The remaining salty toxic sludge is stored in ‘transfer ponds’. Some companies have ‘pilot projects’ to drill another well below the coal seam and reinject the sludge there. In the past there was talk of the salt being recovered and used for table salt but now that has changed to industrial purposes. The only other alternatives are to dump it in the ocean or into landfill. Due to the high costs of disposal most of this toxic sludge sits in ‘transfer ponds’ with spillways waiting for the next flood. The method of disposal of this salty water is one of the major concerns of people opposed to CSG. The known spills from these ponds have had catastrophic effects on the landscape and have continued to spread to the surrounding environment over time.

When the gas no longer flows from the wells they are capped with steel piping and cement to stop the water in aquifers or the Great Artesian Basin leaking into the coal seams below and to secure the hydraulic pressure. Over time the earth shifts and salt corrodes steel. People opposed to CSG are concerned that thousands of capped wells will create an environmental disaster for future generations.

‘If these processes concern you the best thing you can do is contact the gas companies that work in your area and ask them questions,’ said Karen. ‘Ask them where is all the waste salt going? Where is all the treated (RO) water going? Can you explain how the reverse osmosis process can filter out those contaminants that we are so fearful of. Get educated, then write letters to politicians and the editor of your local newspapers.’