Plans to build an incinerator at Haresfield could fall down because the site is near to an area of outstanding natural beauty.
It comes as plans to build four wind turbines near Stinchcombe were thrown out by a Government inspector because of the impact they could have on the environment.
Now planning experts at Stroud District Council have warned that the £500million scheme by Gloucestershire County Council and incinerator firm Urbaser Balfour Beatty to build a waste-to-energy plant at Javelin Park could suffer the same fate if they are heard by an inspector.
Green energy firm Ecotricity had hoped to build their turbines in the Vale of Berkeley but the plan was rejected by the Stroud council.
Then they went to appeal but an inspector backed the council's decision.
Gloucestershire County Council and UBB have been told they could face a similar problem if the incinerator plans are picked up for an appeal or judicial review.
Sue Oppenheimer, chairman of protest group GlosVAIN, said: "I agree a 100 per cent with the concerns.
"It seems reckless to continue with the plans.
"If four wind turbines are going to have an impact on the environment then this huge building certainly will. It is unacceptable."
But a UBB chief has dismissed the claims.
Javier Peiro, project director for UBB, said: "Our proposals for an energy from waste facility at Javelin Park are not located within an Area of Outstanding Natural Beauty.
"Every planning application should be considered on its own merits and Javelin Park is allocated in Gloucestershire's waste core strategy as a suitable site for a strategic waste management facility."