COUNTY HALL is being urged to come clean about sites shortlisted for a £100m incinerator, amid claims that key decisions have been taken in advance of a full council debate.

Oxfordshire county councillors will next week discuss the implications of burning 200,000 tonnes of household waste a year in a plant to create electricity for thousands of homes.

But some councillors have expressed anger that they will be debating alternatives to burying waste in the ground, with the key decision to build a giant incinerator already made.

The Green Party is today demanding that the list of proposed sites for an incinerator be made public, with locations of schemes from shortlisted companies all immediately released.

The Oxford Times reported before Christmas that after a year assessing alternatives to landfill sites, County Hall had decided to go for incineration.

But Labour county councillor Val Smith said elected representatives were being given no chance to influence a decision costing council taxpayers millions of pounds.

Mrs Smith, who secured the full council debate on waste treatment which will take place on Tuesday, said she was appalled to hear officers declaring that the council was to go for energy-from-waste technology.

She said it represented "a bad day" for Oxfordshire, adding: "It is extremely disappointing that the decision has been made before councillors have had the chance to have this discussion.

"I thought we had seen a real change at the council, with councillors able to have a proper discussion about something that will cost council taxpayers an awful lot of money.

"But if the council is already seeking contracts, it is fairly obvious that a decision has already been made. Maybe we would not win the discussion. But at least we would have had the opportunity to have it.

"Ordinary people have strong views about this. It has implications for our children and grandchildren. And we have to be seen to be making the right decision for them."

Mrs Smith said she had begun with an open mind about the best technology, but after undertaking her own research she was increasingly opposed to incineration.

With four companies believed to be shortlisted, Green county councillor Craig Simmons said the debate would take place with some councillors aware of the proposals from companies and others being kept in the dark because of commercial sensitivity.

He said: "To have a debate without having that information is ridiculous. Clearly some people in the council have access to this information. It is not a level playing field."

The Green Party has also complained that the decision "leaked out" shortly before Christmas when it was unlikely to register with local residents.

He added: "Numerous studies have shown that incineration produces very small amounts of energy and relatively high levels of climate damage."

Roger Belson, council cabinet member for sustainable development, said: "It is ultimately up to the council cabinet to make the final decision anyway, although it is important for the council to have the opportunity to express their opinion. We have not been keeping members in the dark. It is not a stitch-up."

He said the proposed sites were only known to members of the Waste Treatment Board, made up of representatives from the county and district councils.

He added: "We would like to be as open as possible. But we have to respect the confidentiality of the companies involved. Not even members of the county council cabinet or district councils whose borders they are in know at this moment."

He said the list of sites could be not be released until after a shortlist of between two and four companies was declared.

A contract is expected to be signed in 2009, with the incinerator operating by 2012 or 2013.

Contractors on the original shortlist included the companies who run landfill operations at Sutton Courtenay and at Ardley, sparking speculation that the incinerator could be accommodated on a landfill site. There have also been fears it could be built on the outskirts of Oxford.