Locals in Western Australia's Wheatbelt fear they will become a dumping ground for Perth's rubbish after the state's environmental watchdog recommended signing off on the controversial proposal to build a new landfill site.

The project was first proposed near the town of York more than a decade ago but has just been given conditional approval by the Environmental Protection Authority.

The Great Southern Landfill project now sits with WA's Environment Minister Reece Whitby, who must decide whether the project, which would see up to 250,000 tonnes of waste dumped at Allawuna Farm annually, should go ahead.

Avon Valley Residents Association chair Keith Schekkerman said it had always faced strong community opposition.

"We hope that the government will veto the whole project as being environmentally unsound," he said.

The Shire of York, which lies just beyond the eastern fringe of Perth's metropolitan area, in the Wheatbelt region of WA, banned landfill developments under its planning rules in 2018. 

The community's main concern was over potential impacts on the environment, with many fearing that leachate, the liquid that drains from the landfill, will impact the Mundaring water catchment.

The fertile soil of the Avon Valley supports an agricultural industry dominated by cropping and grazing, and Mr Schekkerman said the landfill would be located next to the water catchment.

"This alone should raise some alarm bells," he said. 

"Landfills will leak and over time pollute the water table, which in all likelihood is connected to the catchment area."

But Mr Schekkerman said the waste being transported the 80km from Perth to the site was also a sticking point.

In its report, the EPA acknowledged the potential for leachate to seep out of the landfill causing contamination of surface and groundwater.

But it said the project's proponent, Alkina Holdings, had provided enough information to show that there would be no significant impact on inland waters.

It said the landfill's design was consistent with current industry practice and was suitable for the proposed location.

Kay Davies, whose farm is near the proposed landfill site, said the fight had been a lengthy and arduous one, and the EPA's latest recommendation was a disappointment.

"I really feel that this is a big mistake," she said.

Beyond their environmental concerns, they were also worried about the danger of hundreds more trucking movements on country roads.

It comes as deadlines loom on a number of major landfills set to reach capacity in Perth's metropolitan area.

Alkina Holdings has justified its proposal by pointing to figures estimating a 20 to 60-million-tonne shortage of landfill space in WA by 2050.  

Alkina said the proposed landfill would also meet the future waste needs of the local region.

And while the state government has a vision for a sustainable, low-waste future, its latest state infrastructure strategy said landfills continued to play a role for the foreseeable future.

The EPA's recommendation is now subject to an appeals period, with the Shire of York and residents preparing to lodge their opposition.

Minister Whitby acknowledged the recommendation, noting it was based on environmental factors only.

"The EPA recognises the level of community concern and notes the proposal is not consistent with the Shire of York’s current planning scheme," Minister Whitby said. 

He planned to consult with his cabinet colleagues, including the planning and water ministers, at the end of the appeals process.

"Land use planning, as well as social and economic impacts, will be considered before I make a final decision," Minister Whitby said.