Santos said losses of up to $100,000 a day caused by protesters in the Pilliga forest would be passed onto consumers when gas from CSG wells comes online.
Head of Santos’ east coast arm, James Baulderstone, said sustained protests at work sites in north-west NSW were causing delays and pushing up costs.
The comments come after around 120 farmers and community members descended on the CSG site on Thursday, disrupting work by the oil and gas giant for hours.
Baulderstone said there was a group of around 20 permanent protesters camped in the forest, The Australian reported.
"These people are diving under trucks, bolting themselves on, refusing to comply with police, they are taking the law into their own hands . . . that's where these groups overstep the line," he said.
Having lost around a month’s worth of work at the project, Baulderstone warned costs would be handed over to consumers.
"What it does is adds to the cost base. At a loss of $100,000 a day, when I sell the gas in three years the consumer will have to pay for a portion of that," he said.
As part of its work in NSW, Santos plans to drill 15 exploration wells in the Pilliga State forest.
The company says it has all the required approvals to undertake CSG activity in the area, stating it would supply 25 per cent of NSW's gas needs short-term and up to 50 per cent long-term.
Activism has been common at the site as some residents accuse Santos of not having a social licence in to operate.
They say CSG work will affect water and have lasting environmental impacts.
“The water under the Pilliga, recharged in this forest, supports the entire region, and that’s why people have come from across the region to risk arrest to stop Santos from drilling into the Pilliga again,” Spring Plain farmer Kim Revell said.
Baulderstone said debate about water and the environment was important but urged activists to fine a “middle ground”.
“Which isn't doing everything everywhere, but neither is shut the gate and do nothing," he said.