British shale gas developer Cuadrilla said said Oct. 29 initial analysis of gas fracked from the second well at its site in northwest England is high quality and shows the country is sitting on a huge natural gas resource.

Cuadrilla began fracking at the second well at Preston New Road earlier this year, but was forced to stop in August after operations caused a 2.9 magnitude earth tremor.

Fracking at the first well at the site, which started last year, had already been halted several times due to seismic activity.

Regulator the Oil and Gas Authority (OGA) has suspended fracking at the second well while it carries out analysis following the tremor, but the company began testing flows from the site earlier this month.

Chief Executive Francis Egan said early tests show the gas extracted was almost free of impurities and had a high calorific, or heating, value.

“Further testing and analysis will be required to validate sustained gas flow rates,: he said in an emailed statement. “There can be no doubt, however, that the UK is sitting on a huge natural gas resource of the highest quality.”

Fracking, or hydraulic fracturing, involves extracting gas from rocks by breaking them up with water and chemicals at high pressure.

The government has signaled support for the shale gas industry and is keen to cut the country’s reliance on imports of natural gas, used to heat around 80% of Britain’s homes.

However, fracking is fiercely opposed by environmentalists who say extracting more fossil fuel is at odds with Britain’s commitment to reduce greenhouse gas emissions.

Cuadrilla is 47.4% owned by Australia’s AJ Lucas, while a fund managed by Riverstone holds a 45.2% stake.