The audit conducted last November found the yellow-lidded recycling bins had a contamination rate of 12 per cent, higher than the 6 to 10 per cent national average.

Some 62 per cent of the rubbish thrown into the red-topped general waste bins should have been disposed of in either the green-lidded food and garden organics bin, or the recycling bin, according to the audit results.

Council's waste education officer Alice Kent said residents could improve simply by understanding what the items they buy are made up of.

"Whether it's cardboard, paper, or plastics and just making sure it's getting in the right bin," she said.

Soiled and shredded paper and cardboard were found in high volumes in red bins when it should be in the green. Meanwhile, polystyrene products and hazards like batteries, light globes, mobile phones, and printer cartridges should be taken to Gregadoo waste collection.

When such high volumes of contaminants are collected with the city's recyclables, Ms Kent said it is not a matter of simply filtering them out.

"Recycling is slightly more problematic. There is an automatic component in the processing of recycling, so clearly that's an area that we need to get better at."

Since January 2018, China's import ban on anything with contamination rates above 0.5 per cent has resulted in tonnes of Australia's recyclables being diverted to landfill or unused stockpiles.

"Most of our recycling is getting through, so I'd say it's not so much a problem here, it's more an issue for metro areas like Sydney and Melbourne," said Ray Carroll, CEO of Wagga Council contractors Kurrajong Recycling.

Some of the city's recycling is channeled to Tumut, but the majority ends up in Sydney or Melbourne. What happens from there is unknown. "We have to find more end markets for our recycling in our own country, to save it from landfill entirely," Mr Carroll said.

Green waste collection has topped the council's audit honour roll.

Last year's sample audit returned only two per cent contamination across the city.

"In the first 12 months of the FOGO contract, nearly 10,000 tonnes of material has been sent to compost, said Mayor Greg Conkey.

"That's 10,000 tonnes that hasn't gone to landfill, that's an incredible result."

The concentration of well-managed green waste has meant that the city is now able to begin turning the collections into usable compost, with the help of a processing plantation in Carrathool.

It will be trialled on sports grounds around the city, and will be made available to the public for free at this Thursday's producers market.

Only 88 of the nation's 500 councils are currently participating in the green waste compost strategy.

To further tackle the recycling and general waste problems, information packs have been circulated to homes across the city.

"There's a website, yourwaste.com.au and there's an A to Z guide so residents can search particular items on there," said Alice Kent, council's waste education and communications officer.

"Now that we've had this waste audit done, it's really highlighted the areas we need to focus on."