Plans to build a nuclear waste facility on the Lincolnshire coast could hit tourism, campaigners warned after a council agreed to look at the proposal.
Radioactive Waste Management (RWM), a government company, has identified a potential site at a former gas terminal in Theddlethorpe, near Mablethorpe.
Lincolnshire County Council (LCC) agreed at a meeting on Tuesday to join a working group to explore the idea.
Opponents said the move would create uncertainty for local businesses and residents.
As part of its role, a working group would help to identify a search area to carry out more feasibility studies and would engage with local communities.
However, campaigner Ken Smith told the meeting the proposals could put people off coming to visit the coast, adding RWM could walk away at any moment, leaving tourism businesses with a "Sword of Damocles" hanging over their heads.
"The proposal is not a matter of we could lose tourism, and gain extra jobs… it's a matter of we could lose tourism and gain absolutely nothing," he said.
"To my view… you're taking a huge gamble and it's not one I will be prepared to take myself."
Councillors, who voted to move the plans forward, felt they would be left unable to influence any future decisions if they refused to join the group.
Councillor Ian Fleetwood said: “It’s far better to be inside the tent, gaining information... rather than being on the outside looking in."
Ray Wootten, who chaired the meeting of the authority's environment and economic scrutiny committee, said: "Today demonstrates there are concerns, however, we haven't got a view whether we support it or not.
"And I believe - quite rightly so - the residents will have the final say."
Before the meeting, about 20 people from campaign group Guardians of the East Coast staged a protest outside.
Sara Bright, from the group, told the Local Democracy Reporting Service she understood the council's position, but said: "They feel they have to be in the working group to have a seat at the table, but if no council participates in the working group there won't be one.
“If RWM give millions over the years and find that site to be suitable according to their standards, do LCC really think they will be able to withdraw?”
She added the group was planning to stage a further protest in October and would be seeking legal advice.
RWM said it had invited both the county council and East Lindsey District Council, which covers Theddlethorpe, to join a working group to explore whether the former Theddlethorpe Gas Terminal site might be an appropriate location to securely dispose of the UK's higher activity radioactive waste - known as a Geological Disposal Facility (GDF).
“Forming a working group is just a first stage to opening discussions, as a pre-cursor to forming a community partnership that could take these discussions forward for the longer-term," a spokesperson said.
The firm said the multi-billion pound project would create thousands of jobs, but the process ultimately required a community to give clear consent.