The Queensland government is planning to allow coal seam gas companies to bury waste brine from extraction, but activists say it is a "cheap and nasty" option that will come way too late to prevent environmental damage.
The state's draft plan to manage highly salty wastewater was released this week, 26 years after the first CSG project began in the Bowen Basin and after a decade of rapid expansion.
CSG firms currently store brine in 42 tailings dams as a temporary fix, but the reservoirs are at 58 per cent capacity.
The Department of Environment and Science says there is a risk brine could be accidentally released through wall seepage, overflows during excessive rainfall events or structural failure.
The DES expects CSG waste brine to eventually total as much as six million tonnes, which is the weight of the Great Pyramid of Giza.
The government's draft brine management plan says the most viable option is encapsulation, which involves evaporating the water and depositing leftover salt in a lined landfill.
There is no existing encapsulation capacity or regulation in Queensland, but the department said it will not be needed until 2030.
"While encapsulation of salt has been identified as the most viable long-term solution, salt encapsulation facilities are not currently used by the industry," a DES official told AAP on Tuesday.
"However, the department expects industry will continue to explore opportunities to reduce, manage and reuse salt waste."
The DES said it would set up a new process for companies to report annual brine and salt volumes, and review laws for regulating and consulting on encapsulation facilities by 2023.
Lock The Gate Alliance spokeswoman Ellie Smith said encapsulation was a risky option that was favoured by the CSG industry.
She said an industry-favoured option was chosen because the government had failed to adequately consult scientists or landholders.
Ms Smith criticised the timing of the draft plan after the CSG industry has been rapidly expanding for more than a decade.
"It's an extreme case of putting the cart before the horse," she said.
"This latest consultation is extremely disappointing - it's a plan for a plan.
"It's outrageous the Palaszczuk government is even considering industry's preference of burying the salt and washing its hands of the problem.
"The Palaszczuk government needs to get on the front foot with this waste and use independent expert advice to find the best solution, rather than just the cheap and nasty option that industry prefers."
Queensland Conservation Council water policy officer Nigel Parratt said the draft would allow the CSG industry to operate for another eight years without dealing with waste brine.
"Coal seam gas companies have been operating at scale since the mid-2000s without a formal plan to manage their salt waste appropriately," he said.
"Due to the risk to the environment, communities and agriculture, delaying putting in place a plan for how the CSG industry must manage its salt waste for another 10 years is inconceivable."
