Ms Grierson, whose electorate takes in the affected area, said the site had been poorly assessed by the federal government-appointed independent expert scientific committee.

‘‘I am strongly of the view, and [Federal Environment Minister] Tony Burke knows this, that it is the wrong site. It is a sensitive environmental site and it is critical to our water supply,’’ she said.

‘‘I understand the importance of low cost energy for manufacturing but at this stage, for me, the risk to our environment is too high.’’

The expert scientific committee had placed the Fullerton Cove project within the Gloucester geological basin, when it was part of the Sydney basin, Ms Grierson said.

‘‘I don’t think at this stage they have covered themselves in glory in their assessment of Fullerton Cove,’’ she said.

‘‘They also say they don’t have enough data on this at the moment and they hope that this [project] will provide them with some. That’s a terribly distressing and damning admission. ’’

Environment Minister Tony Burke said the federal government’s powers relating to coal seam gas projects were limited to matters contained in federal environmental law.

“There is now a higher level of scrutiny of impacts on underground water as a result of changes made in recent months,’’ he said. “All decisions that are made are rigorous and conform with national environment law.”

The project’s proponents, Dart Energy, and the state government defended the project. Energy Minister Chris Hartcher said the company’s application had been subject to a multi-agency environmental assessment, which found the project was environmentally safe.

A Dart Energy spokesman said all necessary environmental assessments for the project had been undertaken.

‘‘The project has been intensively scrutinised on environmental grounds and Dart believes the project is a sustainable one that will deliver a significant benefit to the local and NSW economies,’’ he said.

Protesters weather poor conditions

RESIDENTS blockading a Fullerton Cove coal seam gas pilot project remained at the site last night despite rain and the threat of blustery wind and possible hail.

The group of about 30 said it would fight on in face of the adverse weather and was planning to hold a meeting on the threat of coal seam gas.

The blockade began on Monday morning in protest against Dart Energy’s plan to drill four test holes at the Fullerton Cove Road site.

Two protesters, Julie Wood and Lisa McDonald, locked themselves to a tractor blocking the site on Wednesday and remained there last night.

Spokesman Lindsay Clout said the group would stay strong and plans to hold a family fun day on Sunday for all Hunter residents.

It will include rides, music and food and Mr Clout encouraged people to get involved.

‘‘This issue is much bigger than Fullerton Cove,’’ he said.

Mr Clout said the group was grateful of the many visiting residents and businesses for their generous support and funding.