An Aboriginal organisation at the centre of a legal battle over the site for a nuclear waste dump says a separate consultation process for indigenous people will do little to dampen its discrimination concerns.

The Barngarla Determination Aboriginal Corporation took Kimba Council to court over its plan to host a community vote to gauge support for a waste storage facility near the Eyre Peninsula town.

The organisation argued the poll was discriminatory because it excluded native title holders who did not live in the area.

After losing the Federal Court challenge in July, the Barngarla has lodged an appeal in the Full Court.

Resources Minister Matthew Canavan has since written to Kimba and Flinders Ranges councils saying he will approach indigenous organisations reaffirming his department’s offer to pay for a poll of their members, providing them with a voice.

But the Barngarla board told The Advertiser such a poll was “designed to exclude our people from having a say on equal footing to the rest of the community”.

“It is very simple to solve this problem – all which needs to happen is to allow our people the right to vote with the rest of the Kimba community rather that segregate us,” the board said.

The organisation said Mr Canavan had not provided a template ballot paper and associated material so the ballot could be run on equal terms. The council and Federal Government had also not agreed to consolidate all the results into one process.

The Barngarla board has written to Indigenous Australians Minister Ken Wyatt asking him to intervene.

Three SA sites are being considered for the radioactive waste dump – two near Kimba and one at Wallerberdina Station, near Hawker in the Flinders Ranges. It would hold low and intermediate-level waste, primarily from the production of nuclear medicines.

Polls in the Hawker and Kimba communities were due to happen in August 2018 but were stalled after the Barngarla court appeal was flagged.

The Adnyamathanha Traditional Lands Association (ATLA) has also lodged a complaint with the Human Rights Commission.

Meanwhile, Government staff on Tuesday confirmed at a Flinders Ranges-based consultative committee meeting the minimum size of the nuclear site and its surrounding buffer zone would increase from 100ha to 160ha – as claimed by a source close to the project in The Advertiser last month.

The Government says the extra space will allow for features such as a water treatment plant, power infrastructure and road access, depending on the selected site.

Mr Canavan said the Government had “listened carefully” to communities when shaping ballot boundaries.

“At Kimba it extended to the entire local council area, while at Wallerberdina Station it is the local government area plus an approximate 50km radius,” he said.

“Wherever a boundary is defined there will be a number of groups outside that line, but the process gives those people the ability to fully participate by making a submission that will be taken into account in the decision-making process.”

A spokeswoman for Mr Canavan said details of polls among indigenous organisations would be worked out alongside any groups who wanted to participate.

Maurice Blackburn lawyer Nicki Lees, representing ATLA, said the organisation had made it clear it opposed a nuclear waste dump on its traditional land.

“If the Government is considering further consultation on this project, we would consider this in due course,” she said.

“However, it is important that this is a meaningful process, which hasn’t occurred to date.”

Adnyamathanha woman Regina McKenzie has previously told The Advertiser the long-running debate had disrupted her community.