They hoped the "Can't Eat Coal, Can't Drink Gas" rally would make people aware that although a gas plant in the Scenic Hills Protection Area wouldn't happen, AGL still had plans for the site.

"What we're finding out in the community is that everyone thinks the Camden Gas Project stage three that was going to come into the Scenic Hills is over," said Scenic Hills Association campaigner Jacqui Kirkby.

"Because the newspapers made a big deal about the gas treatment plant when the minister knocked that on the head, people thought it was over.

"But it's still going ahead — just without the gas plant.

"They're planning to put 72 wells in, along with all the infrastructure."

Ms Kirkby said the SHA did not intend to let the issue go and took heart from the statewide and national interest in the Scenic Hills shown at the rally.

More than 1200 people from around the state attended the event on Sunday, March 20 in Martin Place where Greg Burke of the SHA spoke.

"There were people who came down from Queensland to speak at that rally," she said.

"They came down to warn us what you can expect if it goes ahead here because it's a disaster up there."

The rally was organised by the Lock the Gate Alliance to oppose the devastating impact of mining on the environment, community health, people's livelihoods, property values and water and food security.