Doubts have been raised about claims made in the environmental impact statement for Santos’ controversial plans to drill 850 coal seam gas wells in and around the Pilliga state forest.

The full statement has not been publicly released yet but questions are being raised about the economic and environmental claims in it, which are summarised in a “fact sheet” released by Santos.

Rod Campbell from the Australia Institute said he would be keen to see the full statement, since the summary seemed to differ to claims made in a report commissioned by Santos in 2011.

The new summary claims the project will create 200 ongoing local jobs. But the 2011 report said it would create only 168 ongoing jobs, with only 38 of those in the immediate local area.

“The gas industry have a record of being loose with the truth around this project,” Campbell said. “[The industry body] wouldn’t even turn up to a forum to discuss its economic impacts with the community and with members of Queensland communities affected by gas. Then they lied about not being invited.

“So we will be very interested in what the EIS has to say about jobs, economic impacts and ongoing gas supply to NSW and the rest of the east coast.”

Santos said they had data from more than 13,000 hours of on-ground surveys over several years, which assured them they would avoid significant environmental impacts.

The full document will be released in the coming days or weeks and assessed by the NSW Department of Planning and Environment.

Mike Young, director of resource assessments at the department, said: “The department will be consulting broadly on this application, including holding public information sessions in the local area during the exhibition period.”

After almost three years of delays submitting its environmental impact statement for the Narrabri project, Santos packaged it into a “non-core” standalone business in 2016, raising expectations it would either be scrapped or sold.

Georgina Woods, from anti CSG group the Lock the Gate Alliance, said: “Santos is setting the scene for another showdown over coal seam gas in regional New South Wales in the lead up to the 2019 state election.

“This project makes no sense economically, socially, politically or environmentally and it is our hope that it soon falls over under the weight of public opposition and economic absurdity.”

Sally Hunter, a farmer and mother from Narrabri, said the release of the EIS would trigger a major showdown.

“This community is well-informed about the damaging impacts of unconventional gas and will confront this threat with unity and energy,” she said. “It is an existential threat to our farms and livelihoods and that is how we will respond to it.

“It is only a matter of time until Santos’ Narrabri gas project contaminates our precious groundwater again.

“We cannot accept any risk to the groundwater on which we utterly rely. A CSG field in the Pilliga would be the beginning of the end of the health and productivity of our food producing region.”

Coal seam gas has been proposed as a low-emissions fuel but those claims usually fail to take account of leaks of methane gas directly to the atmosphere. Once those are considered, research suggests that coal seam gas could be at least as carbon-intensive as coal.