Cory Environmental Resource Management want to build a plant to produce and export electricity from the Hafod Quarry site in Johnstown and sell it to the National Grid.

According to a planning application submitted to Wrexham Council, the proposals will cut down on the amount of greenhouse gases released into the atmosphere.

Hafod environmental campaigner Pauline Smout said she had concerns about the emissions the new plant could give off.

The development would be built to the north east of the landfill and would eventually consist of four gas engine generators. Cory initially want to build one at a time, eventually building more as increasing levels of landfill are deposited.

Gases produced by decomposing biodegradable waste within the landfill site are currently extracted through pipes and burnt off.

The planning application reads: "At present gas at the landfill is simply burnt off by the flare stack at the site. The proposed development... helps combat climate change through generating electricity from the landfill gas, thereby avoiding the need to generate an equivalent amount of energy from burning fossil fuels.

It goes on: "It is estimated that construction would take approximately six months.

"Once constructed, the landfill gas engines will be operational 24 hours a day, seven days a week for the lifetime of the landfill and for the subsequent period while sufficient gas is being generated to sustain the plant."

It adds: "The proposed development also helps combat climate change through generating electricity from the landfill gas, thereby avoiding the need to generate an equivalent amount of energy from burning fossil fuels."

Wrexham Council confirmed an application had been received, but no date had yet been fixed for its consideration.

Campaigners fought for a number of years to stop landfill at the former quarry near Johnstown, where Mersey Waste Holdings began tipping in 2006.

Speaking about the new development Mrs Smout said: "We have no objection to them generating electricity but we have profound concerns about the emissions from the generator.

"Especially as we have a similar thing nearby with another site in Ruabon. We believe this could cause serious health problems."

Landfill operations at the site began in August, 2006. A planning application for the infilling of Hafod Quarry with domestic, commercial and industrial refuse was refused by Clwyd County Council, but after an inquiry, permission was granted by the Welsh Secretary, on appeal, on July 10, 1995.

Part of the southwestern corner of the site was designated as a Site of Special Scientific Interest in July, 2001, and then as a Special Area of Conservation in December, 2004.

Cory Environmental formally took over the ownership and operation of the Hafod site in September.