The rediscovery of an old VHS tape, left forgotten on the shelves of the Northern Territory Library, has unearthed a tense and important piece of Australian history.

Key points: The 1980 documentary Dirt Cheap showcased the Mirarr people's fight against uranium mining

The 1980 documentary Dirt Cheap showcased the Mirarr people's fight against uranium mining The Northern Territory Library recently hunted down the only digital copy of the documentary so it could be shown at a film festival

The Northern Territory Library recently hunted down the only digital copy of the documentary so it could be shown at a film festival Filmmaker Ned Lander says the movie created a stir at the time of its release

The rare copy of the nearly 40-year-old documentary Dirt Cheap, which details the early pushback against uranium mining in Kakadu National Park, was practically unwatchable due to its age.

But the recent find sparked a "goose hunt" for the lone digital version in existence, so it could be screened to a new generation at the Darwin International Film Festival.

"Dirt Cheap is one of those films that I'd heard rumours of over the years — it was made around that really heady time in the 1970s where land rights for Indigenous people was being developed," Charlie Ward, the library's collection development coordinator, said.

"We investigated whether we had it in the library collection, and what I discovered was there was a VHS sitting on the shelf, but being 40 years old, it was pretty blurry.

"It was a bit psychedelic.

Charlie Ward, the Library & Archives NT collection development co-ordinator, found an old VHS of Dirt Cheap. ( ABC News: Matt Garrick )

"So then that led into a whole process of trying to find another copy, and it turned out that it hadn't ever been digitised.

"There wasn't a mastered version anywhere in any cultural institution in Australia."

But the search eventually yielded a result, with a copy found in a hard drive in the seaside Darwin suburb of Fannie Bay.

"That was the only place that this film existed in a form that could be viewable these days," Mr Ward said.

Filmmakers 'surrounded by wild pigs and crocodiles'

One of Dirt Cheap's filmmakers, Ned Lander, said making the documentary had been a "life changer" and it had created a stir upon its release in 1980.

Film producer Ned Lander worked as a cinematographer on Dirt Cheap, and said it created a stir when it was released. ( Supplied: Ned Lander )

"It's incredibly hard work making documentaries like that, particularly in those days, in the 1970s, trying to raise the money and convince people that's it's OK to go and spend months and months out bush," Mr Lander said.

"And 'no', you wouldn't be in touch with them, and, 'yes', you were going to spend all their money.

"We were surrounded by wild pigs and crocodiles, and coming from the city, you were somewhat out of your depth."

The film documented the concerns of the Mirarr people during what was a tense period of negotiation in the lead-up to the 1979 Ranger Uranium Mining Agreement.

It also showcased the pressures and broken promises the traditional owners faced.

"When we made Dirt Cheap they were in the final stages of negotiating this agreement, which somehow brought together the idea that traditional owners would, inevitably, agree to uranium mining on their country," Mr Lander said.

Solicitor Eric Pratt, then Northern Land Council chairman Galarrwuy Yunupingu and minister for Aboriginal affairs Ian Viner. ( Supplied: Ned Lander )

"It was very, very apparent to us that people were not ready to sign the agreement in relation to mining, and this was being done under pressure.

"I think the film shows that — that the government had decided it was time but the people hadn't."

Mirarr resistance inspires protests around nation

Against the push of government and business interests, the Mirarr stood resolute in their bid to protect their land.

"As a child growing up I saw the struggle of my family, including my grandfather — they [had] been struggling," traditional owner Jimmy Nabanardi-Mudjandi said.

Mirarr senior traditional owner Yvonne Maragarula stands on Mirarr country at the Ranger uranium mine. ( Supplied: Dominic O'Brien )

"I'm really proud of them, but it's sad because they're not here to see what the new future of Jabiru's gonna be."

The resistance from the Mirarr had a flow-on effect around the nation.

Banner-waving protesters took to the streets in Melbourne and Sydney in great numbers, scenes which Dirt Cheap captures in vivid detail.

"Mirarr people got major support from around Australia, from around the whole nation," Mr Nabanardi-Mudjandi said.

"There's been lots of support all through the years, and they still support us now."

Next stage of uranium mining looms

In the decades since the film's release, uranium has been mined at Kakadu, but the Ranger mine is now expected to wind up in 2021.

Mr Nabanardi-Mudjandi said it was vital the land was protected during its rehabilitation.

"We are watching them, what they're doing," he said.

Mr Nabanardi-Mudjandi will be a special guest when Dirt Cheap screens as part of the Darwin International Film Festival at the Northern Territory Library at 5:30pm on Wednesday.