Hundreds gathered in Kimba on Sunday to rally against the proposed National Radioactive Waste Management Facility in the wake of the announcement that Kimba would be the host.
Resources minister Matt Canavan announced on Saturday morning that he had selected Napandee at Kimba, just a day before the planned protest.
No Radioactive Waste on Agricultural Land in Kimba or SA secretary Toni Scott said the group began planning the rally before Christmas because they believed their opposition to the facility was not being heard.
"It's just a way of people coming along, listening to our concerns, being here showing us their support and showing that there is big opposition on Eyre Peninsula," she said.
Among attendees at the rally were people from neighbouring communities including Whyalla and Cleve, as well as members of the Flinders Ranges community protesting in solidarity with Kimba after the proposed site in their community was ruled out in late 2019.
Mrs Scott said it was important those outside Kimba's boundaries had a chance to have their opinion heard after being unable to participate in the vote.
She said Minister Canavan's announcement only referenced the opinions of submissions made locally despite the government receiving 3200 submissions altogether.
"The people beyond Kimba on our boundaries haven't really had an outlet to express their opinion apart from writing a submission," she said.
"The minister hasn't taken the outside submissions into consideration in his media release anyway."
She said Mr Canavan implied opposition outside the district was coming from anti-nuclear interest groups rather than concerned community members.
"He hasn't actually acknowledged people on Eyre Peninsula who are opposed, he's basically said that they are part of an anti-nuclear group which is pretty disrespectful," she said.
Among a busload of attendees from the Cleve district was Darke Peak farmer Doug Pearson, who said farmers in his district were taking on the same reputational risks without the compensation or chance to be heard.
"They don't segregate the Kimba grain from the Darke Peak grain or the Cleve grain," he said.
Mr Pearson said with most of his business dealing with overseas markets, he was concerned buyers would demand a lower price due to the proximity of the facility.
He said the voting process was "absolutely ridiculous," with only Kimba residents allowed to participate in the ballot and little consultation held outside the district borders.
Speakers at the rally ranged from local farmers to politicians, with each speaker sharing the sentiment that allowing a single landowner to volunteer a site before community consultation had been an inherently divisive and painful process.
Among the speakers was federal senator Rex Patrick, who said his Centre Alliance party and the Greens would work to send the required enabling legislation to a senate committee to ensure the political process was scrutinised.
Mrs Scott said the group was "horrified" the government had chosen to make the announcement the day before the rally and while neighbours had previously been given prior warning of major announcements, they only found out Napandee had been selected late Friday night when news reports began circulating.
She said communication with the federal government ahead of the rally had received no response.
"We thought it might have been nice if (Mr Canavan) could have sent a representative to come to our rally and listen to what we have to say... and then maybe make your decision after rather than the day before," she said.
"All it shows is they don't really care about what the opposing people have to say."