Resources Minister Chris Hartcher announced earlier this month the moratorium, which was due to end on December 31, would be extended pending the completion of an independent review.

"The NSW government recognises significant recent community concern over the potential for pollution of aquifers by the coal-seam gas industry as part of the fracking process," Mr Hartcher said. "That's why we're proceeding with caution and making sure the proper frameworks are in place for the protection of our aquifers, our environment and our prime agricultural land."

Greens mining spokesman Jeremy Buckingham welcomed the lengthening of the ban but said it should be extended to the whole industry.

"The minister should clarify whether the fracking ban pertains to existing approvals such as AGL's operations at Camden and Menangle Park."