Anti-fracking activists claim the public has been “misled” because there was no mention of shale gas when Cheshire West and Chester Council gave permission for test drilling near Chester and Ellesmere Port.

Nexen Exploration UK Ltd, now owned by IGas, gained permission to drill two exploratory boleholes for coal bed methane (CBM) appraisal, production and extraction at Ince Marshes in April 2010.

The council was told the average depth would be 762m, but in fact the company drilled to 1,469m and found shale around that depth.

The same company gained permission to drill two exploratory boleholes for CBM appraisal and production at Ellesmere Port in January 2010. The test drill operation is due to begin this autumn but the firm now describes Ellesmere Port as a shale licence area.

Anti-fracker Matt Bryan said: “The public have been misled over the company’s hidden agenda to go after shale gas.

“There was no mention of looking for shale in the early stage documents, no mention of hydraulic fracturing – and they have drilled much deeper at Ince Marshes than was indicated by the average depth of 762m that was anticipated (1,469m in reality) in the application with seemingly no repercussions because the council has failed to stipulate a maximum drill depth.

“In recent press releases and investors reports, IGas are openly describing the Cheshire area as shale licence deposits and as part of their wider hydraulic fracturing programme with no mention made to CBM.

“We predict they will use this same loophole on their other licences across Cheshire.”

Cheshire West and Chester Council was unaware IGas had drilled to 1,469m instead of the anticipated 762m at Ince Marshes but insisted there was no breach of planning consent because “the presence of shale gas could well have been detected within this overall depth (762m) and planning permission has not been breached”.

But geologist Kevin Walsh said even if IGas had only drilled to 762m, it would be impossible to encounter shale.

“You cannot accidentally hit the shale gas as there is over 1,000 feet of millstone grit below the CBM coal seams,” he said.

IGas spokesman Paul Smith said: “Our exploratory work involves drilling as far down as the dinantian limestone in order that we meet our obligations to the British Geological Survey.

“Should we encounter shale gas, we will appraise it but we do not have planning permission to carry out the process of hydraulic fracturing necessary to extract it.”

“As part of a broader strategy for the North West we are interested in the potential of shale gas reserves in the region and recently published a report which highlighted potential economic benefits, but as yet no sites have been identified.”

British Geological Survey spokesman Clive Mitchell denied his organisation set a drill depth but said it could be a governmental requirement.