The south London incinerator project faces the risk of collapse according to secret documents seen by this website.

Despite opposition, Viridor was granted planning permission in 2014 for an energy recovery facility at the existing landfill and recycling site in Beddington Lane, Sutton.

The contract is the biggest ever signed by the councils involved and includes councils run by Labour, the Conservatives and the Liberal Democrats.

From May 2013: Council grants planning permission to south London incinerator

The incinerator will deal with up to 302,000 tonnes of non-recyclable waste from Merton, Croydon, Sutton and Kingston councils and burn it to create energy distributed to neighbouring homes in the form of heat and electricity.

Opponents, including campaign group Stop the Incinerator, hired a legal team including Ed Miliband's wife Justine Thornton in an ultimately unsuccessful bid to block the proposals.

But, according to restricted documents released by mistake into the public domain, waste giant Viridor is unhappy with the permission it was given and wants a new permission to run a bigger, noisier site with longer opening hours.

If it fails it says it would be "not obliged to proceed to the construction of their proposed facility".

The restricted report, published on the South London Waste Partnership (SLWP) partner Kingston Council's website, says: "Viridor has been of the view that certain conditions of the approval could render it ‘unsatisfactory’ under the terms of the Project Agreement.

For more on the history of the incinerator fight see

"The issues contributing to this view were chiefly around the opening hours, the noise restrictions and the costs of complying with the conditions imposed under the planning permission being in excess of the £1.4m, a figure stipulated in their contract with the Partnership.

"This does not mean that Viridor has at any time formed a view that the decision of the local planning authority was wrong, but Unsatisfactory Planning Permission would mean that under the terms of the project agreement with the Partnership they are not obliged to proceed to the construction of their proposed facility."

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Kingston Council has since removed the report from its website. 

After being given the go ahead to build the plant in March 2014 Viridor gave notice, under the terms of its contract with the SLWP, that it considered the planning permission issued by Sutton Council to be "unsatisfactory".

According to the parts of the report that were classified private, the contract allows the waste giant to consider the proposals as unsatisfactory if it costs Viridor more than £1.4m to work in practice, for example for any "onsite and off-site works" required to meet planning requirements.

Chief among its issues are opening hours and noise restrictions and this has led to Viridor to seek "further clarity" from Sutton.

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The SLWP believe there has been "significant progress" but that "ultimately, if Viridor continues to consider the planning consent to be ‘unsatisfactory’, it would need to decide whether it still wishes to proceed to construction of the facility, or move to a Revised Project Plan.

The report added: "Should Viridor decide not to proceed to construction as a result of an unsatisfactory planning permission both the Partnership and Viridor will need to consider a Revised Project Plan under the mechanics set out under the Project Agreement."

The restricted 133 pages of the report, which include details of unsuccessful bidders for a refuse and recycling site contract, finances and communications strategies, have since been removed but were online for days.

A statement published this afternoon on Viridor's website read: "Viridor has been informed that confidential documents relating to the contractual process were published on the Kingston Council website.

"The published report included information regarding Viridor’s options on how to proceed with the project, should the cost of meeting restrictions placed by planning permissions become prohibitive.

“Unsatisfactory planning” is a contractual mechanism enabling Viridor to review restrictions imposed by the planning conditions.

"Viridor has submitted the details required by the planning conditions to London Borough of Sutton and these have recently been substantially approved.

"Viridor is not seeking amendments to opening hours or noise restrictions. Viridor continues to wait for the outcome of the Challenge, currently with the Court of Appeal, regarding the planning permission granted by the London Borough of Sutton.

"Viridor looks forward to implementing the planning permission in the near future in order to provide an essential residual waste solution to the residents of South London."

The non-restricted section report also reveals that one in three dump workers have faced disciplinary action since Kingston Council took back from financially troubled EWC in July 2013.

Members of the SLWP were greeted by protestors outside this evening's meeting at Croydon Town Hall, chaired by Merton Labour councillor Judy Saunders with vice-chairman David Cunningham, Kingston Council's lead member for environment.