Shale gas firm Cuadrilla has announced two new exploration sites in the UK.

It announced the two proposed sites in early February as campaigners opposed to plans for fracking in the UK stepped up plans to challenge developers such as Cuadrilla.

"Cuadrilla’s plans for two exploratory sites are part of its plans to assess the full potential of the Bowland shale formation in north-west England."

Cuadrilla’s plans for two exploratory sites are part of its plans to assess the full potential of the Bowland shale formation in north-west England. It says it will apply for planning permission to drill, hydraulically fracture and test the flow of gas from up to four exploration wells on each site.

It will also apply to install two seismic arrays that would monitor the fracking process.

"We’ve been working hard to assess our site options and have undertaken extensive technical and geological analysis," said Francis Egan, Cuadrilla’s chief executive. "As a result of this work, we have decided to focus on just two sites at this time. This will allow us to reduce the potential impact on the local area during exploration while still gathering the important information we need to determine how much gas could be recovered."

The UK government has given its backing to the development of the UK’s shale gas reserves and has proposed a raft of new policies designed to attract investors as well as reduce public opposition to the plans.

However green groups such as Greenpeace have launched a legal challenge to plans for shale gas exploration by encouraging landowners to use trespassing laws to prevent oil firms from drilling horizontally under their land.

"Instead of planning to strip away long-established homeowners’ rights to make way for drillers, the government should take notice of the growing concerns expressed by millions of people, including many Tory voters, and call it a day on this fracking folly," said Greenpeace UK energy campaigner Lawrence Carter.

In September 2011, Cuadrilla announced it had discovered 200 trillion cubic feet (tcf) of gas in place within the Bowland shale in Lancashire. The government believes that shale gas exploration would trigger investments of £3.7 billion per year and create over 70 000 jobs.

It also believes that the gas would help to improve security of supply and help to plug a gap in the power generation sector left by the retirement of ageing capacity.

Sian Crampsie