Wine growers have warned the Hunter's billion dollar wine industry could be put at risk if the state government redirects millions of tonnes of Sydney's garbage to the region.
The government recently revealed that without new waste solutions, Sydney's landfill capacity would be exhausted within the next decade. This would significantly drive up waste management costs due to the need to transport waste to regional areas.
Environment Minister Penny Sharpe said her preference was to increase recycling initiatives rather than build more landfills.
The government is investigating options for new waste management infrastructure to help cope with the growing crisis.
The Hunter's mining voids were previously identified as a potential 'super dumps' for Sydney's waste in the early 2000s. However, the plan was scrapped following a massive community backlash.
Hunter Valley Wine and Tourism Association advocate Ian Napier said local vignerons were concerned that the region could be targeted again.
Among the association's concerns is the potential spread of Phylloxera, a small, aphid-like insect that destroys vines.
"We try to prevent trucks that have come from Phylloxera areas, such as around Camden, because if it gets into the roots of the vineyards it will cause a calamity," Mr Napier said.
"If they were to do anything they would have to do it under some pretty strict ecological guidelines where the truck tyres were washed before they came into the area."
Another concern was increased truck movements throughout the region.
"Traffic is a major issue for the vineyards," Mr Napier said.
"I don't know what the route would be but it would have to come out of Sydney somewhere. You would be adding to the challenges we already face getting up the M1 and M15 (Hunter Expressway)."
Singleton mayor Sue Moore, who was a councillor when the Hunter was last discussed as a potential solution for Sydney's waste problems, urged the government to learn from the mistakes of the past.
"There were a multitude of problems with it last time and I'm sure there would be no appetite for it today. It would still be the same conversation," she said.
"Hopefully the government would be mindful of not going down that path so far that it caused all of the angst that it did last time."
A NSW Environment Protection Authority spokeswoman said the government was taking action to prevent the need for more landfill sites.
"The government recently held the state's first Circular Economy Summit bringing together industry, environment groups and government to discuss how best to achieve this," she said.
The EPA is taking steps to address diminishing landfill capacity, such as developing the first NSW Waste Infrastructure Plan.
"This plan, to be released next year, will strategically guide investment in waste and resource recovery infrastructure where it is needed," the spokeswoman said.
"No decisions have been made about the location of essential waste management infrastructure."