Every week, sometimes ever day, Ramona Cocco would step outside her Rutherford home to air so thick you could cut it.

Any hint of a breeze brought with it a sense of dread for Rutherford and Telarah residents - and an inescapable stink followed by the occasional skin rash, stinging eyes, sore throats and aggravated asthma.

Mrs Cocco detailed this week her frustration at having to make countless calls over decades to the NSW Environment Protection Authority (EPA) about the offending burnt oil odour from the notorious Kyle Street plant.

The chronic asthmatic kept meticulous records of every call over almost 22 years.

If people think this is over because Truegain has shutdown, they are kidding themselves, she said.

Were not in the clear by any means. We dont know whats in the soil at that place, what is leaching into the environment and we dont have a clear picture of a clean up plan for the contaminated waste stored there. This fight is a long way from over.

The residents who battled for decades against the infamous stink are now calling for an independent environmental audit of the Truegain site.

They want answers about whats in the soil and whats being done with the contaminants on site.

For too many years they have heard rumours about drums of toxic waste being buried on the site and they worry, if its true, that its leaching.

The full ramifications of this are yet to come out, Mrs Cocco said. People have turned a blind eye to this for too long and its about time we got some answers. This is a community health issue.

The Truegain stench, which first blanketed the suburb decades ago, sparked an outcry with countless complaints to health authorities and the EPA.

Even after two workers from an adjoining business were hospitalised in May 1999, after suffering nausea and headaches from the smell, Truegain continued to operate.

The companys atrocious environmental record, exposed by a Newcastle Herald investigation, included oil and liquid waste dumping into surrounding waterways and properties dating back decades.

More than 40 former workers have spoken out about what they witnessed while working at the refinery detailing how vast quantities of a chemical cocktail were pumped into creeks that run to the Hunter River.

Truegain was also dumping the notorious contaminant per- and poly-fluoroalkyl [PFAS] into Maitland's sewer and the toxic firefighting chemicals - at the heart of the Williamtowns red zone environmental scandal - have been detected in extremely high levels in a creek behind the refinery.

Numerous people have told how they reported the illegal dumping to authorities, who occasionally took action, only for the pollution to continue.

Former workers explained how Truegain managed to fool inspectors time and time and time again when testing was carried out to determine if the stink was coming from the refinery.

They just used to put the plant on hold when the testing was done, said Jeff Gayford, who worked there for almost a decade.

The EPA would be testing the stack and the plant wasnt working to full capacity so the smell didnt get detected. You got used to the smell after a while working there, but it was far from pleasant.

I could stand outside my house, streets away, and id think, theyve just increased the feed. You could smell it, especially on a foggy night.

Resident Stephen Jordan, who served on the EPAs Rutherford Air Quality Liaison Committee established to investigate the source of the odour, said there was a lack of will to solve the problem.

He said the stink made the lives of many residents a misery.

People would get sick, especially in certain pockets, it was a dreadful situation, he said.

We heard rumours that they werent running the plant when the tests were done and we told the EPA at the time.

Their response was, we can only test what we can when were there at the time. It beggars belief that Truegain was allowed to get away with so much for so long. There was no will to solve or tackle any of it.

Residents battled for decades without any relief against the build up of fumes that floated from the refinery that should have been burnt by the plants afterburner.

Maitland Anti-Stink Campaign was formed and the groups motivation was simple.

We hated the smell, worried about the communitys health and wanted it to stop, Mrs Cocco said.

I think the EPA tried to do a good job, but they didnt have the power. The one thing I learnt over all those years is that they are a toothless tiger.

At the time, the EPA defended its inability to resolve the issue saying it needed indisputable evidence against a polluter to take legal action.

An intensive odour investigation was carried out, but for decades Truegain denied it was the source of the stink, claiming it was being victimised.

In September 2008, the EPA issued Truegain with a notice suspending its environmental licence after it detected deficiencies in the odour control systems at the plant.

Truegain appealed the suspension in the Land and Environment Court and held a press conference to put the human side of the story.

Emotional workers and their families told the media about the impact shutting the plant would have on their lives. The companys spokesman said closure would cost 55 jobs and be a $60 million stab to the heart of the Hunter economy.

Despite desperate pleas from the community to close the plant, the prospect of jobs repeatedly trumped environmental and health concerns.

Worried about the harm on 55 households, Justice Terry Sheahan put a stay on the suspension until further order by the court.

Six months later the Department of Environment and Climate Change announced it had cut a deal to revoke the licence suspension following court-ordered improvements undertaken on the Rutherford plant.

Mrs Cocco said the stench soon returned and it only went away when Truegain closed in September 2016.

The government is now having to grapple with the fallout for the plants operation after toxic PFAS chemicals have been found at the plant and in Stony Creek that runs behind the Truegain site.

The whole place should be cordoned off and independent soil testing done, Mr Jordan said.

It cant be allowed to sit there with so many question marks over what impact it is having. The community deserves better, but then again, it always did.

A spokesman for the EPA said contaminants at the site included PFAS, ethylene glycol, oil, grease and petrol, but he refused to reveal how much was stored there.

He said the landowner had contracted Enviropacific Services to treat and remove material containing PFAS. The EPA required the landowner to clean up the sites above ground storages as a priority prior to any contaminated site assessment, he said.

Maitland MP Jenny Aitchison, who campaigned for years against the stink, has called for a review of the clean up of the Truegain site to ensure no further exposure to toxic chemicals.

Ms Aitchison has raised the issue in parliament numerous times and put a series of questions to the Environment Minister Gabrielle Upton about the future of the site, waste stored at the plant and the clean-up process.