Bill Kerswell, who has sat on various traveller advisory panels, said he fears the Gorsebrook Road site could be unfit for humans as it may have had toxic waste on it in the past.
But Wolverhampton Council said an independent firm carried out ground investigations in the summer and found it to be safe for use as a transit site.
Interactive map shows site of the land:
Spokesperson for the council, Danielle Taylor, said: “As a council, we take health and safety very seriously.
“A comprehensive ground investigation was undertaken this summer by an independent company, Ground Investigation and Piling Ltd, who specialise in such works.
“Their report concludes that there would be no requirements for any remediation works to be carried out with respect to human health for use of the land as a transit site.”
WATCH: Heated public meeting over traveller site plans
There has been a fierce backlash from residents and businesses over the plan for the site in Whitmore Reans, near the Winning Post pub.
A heated public meeting was told this week by the council’s head of business services, Colin Parr, that the site had “received waste in the 1970s for a couple of years”.
And Mr Kerswell said there were concerns about pollution there.
He said: “I have been involved in several tips and former landfills and they are full of toxic waste and appalling chemicals.
“If you wouldn’t put houses on the site then you shouldn’t put travellers on there.”
Council bosses say they must provide a legal site for travellers to pitch up if they are to retain powers to protect 60 public spaces in the city, which could otherwise be left vulnerable.
An injunction protecting the sites is due to be reviewed in December and could be lifted if the legal travellers site is not pushed through.
However, the proposal has proved contentious with people living nearby making clear they are prepared to fight it all the way.