A central Australian Indigenous elder has threatened to throw herself in front of a road train if a proposed radioactive waste management facility is approved to be built on her ancestral lands.

The federal court held a special sitting at the Muckaty community on Monday, 120km north of Tennant Creek in the Northern Territory, to hear the evidence of Milwayi traditional owner Bunny Nabarula, about 84.

Members of the Lauder family of the Ngapa clan laid false claim to the land when they along with the Northern Land Council (NLC) nominated the site for a national nuclear waste storage facility, say members of four other clans who are against it.

In 2007 the NLC nominated the site to the commonwealth and agreed on a package of $9m to be held in a charitable trust, $2m for a road on Indigenous land and $1m for scholarships over five years.

A $200,000 payment was made to a narrow group of Indigenous families, which Nabarula dismissed as dirty money.

She told the court her Milwayi people had principal claim to the land, and that the Ngapa dreaming just passed through it.

"If that dump goes ahead I will go mad," she stood and shouted at the court.

"Me and my family ... We will block the road and let the truck run us over."

She told the court it hurt her feelings to even contemplate the waste facility being approved, but was coaxed back into her seat.

"It will destroy everything," she said.

Justice Anthony North is seeking to ascertain whether those against the facility are opposed to the dump or the deal, and Nabarula said she didn't want it located anywhere on Australian soil.

Tom Keely, representing the NLC, said she had "a lot of complaints" against the land council.

"Whatever they do, it's not quite enough to satisfy you," he said.

He suggested she was against the facility before she really knew what was being proposed, and said Nabarula thought she had more culture and was therefore better than the Lauder family and felt she could take over their lands.

He said that when the dump was proposed in 2007 the Milwayi people did not claim the land as theirs, something Nabarula disputed.

We have got the culture in the bottom of our hearts, she said.

The trial continues.

