The Queensland Department of Natural Resources is considering two controversial applications to mine a river on a sprawling Cape York cattle station, the ABC can reveal.

Key points: The applications are to excavate for gold and tin ore in the West Normanby River

The applications are to excavate for gold and tin ore in the West Normanby River Conservationists describe the plan as "the left hand not knowing what the right hand is doing"

Conservationists describe the plan as "the left hand not knowing what the right hand is doing" Conservationists want in-stream mining banned

This is despite the same cattle station being bought last month by the state's environment department in an effort to ensure conservation of the Great Barrier Reef.

The apparent contradiction — one department potentially approving mining, with another department seeking to protect the environment — has been described by conservationists as "the left hand not knowing what the right hand is doing".

The applications propose the excavation of gold and tin ore in the West Normanby River on Springvale Station, which was bought last month by the state for $7 million.

The West Normanby joins the eastern branch of the river before flowing out into Princess Charlotte Bay and the Great Barrier Reef Marine Park.

The Australian Conservation Foundation's Andrew Picone said in-stream mining was from a bygone era and should be banned, especially in reef catchments like the Normanby.

"You do the mining in the dry season, but as soon as the wet season hits, everything is picked up and sent down the river, and down into the lagoons in Lakefield National Park and then out into the Great Barrier Reef in the marine park," he said.

An example of gully erosion at Springvale Station in the upper Normanby basin. ( Supplied: Kerry Trapnell )

Jeff Shellberg, a geomorphologist with the Australian Rivers Institute, said just a single alluvial or in-stream mine could create thousands of tonnes of fine sediment a year.

"Basically bulldozers and excavators are brought into the channel, dig up the channel bed, the trees and armour layer of the river are removed and they're trying to access sediment and gold trapped in the sediment in the river bed," said Dr Shellberg.

Local farmer, councillor behind one mine application

Last month the Queensland Government announced it had bought Springvale Station because it was the most eroded property on Cape York, contributing 30-40 per cent of the gully sediment in the Normanby catchment.

"If by buying this property we can drive down sediment at the rate scientists say we can, I think that will be money very well spent," said Environment Minister Steven Miles at the time.

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The purchase was slammed by former local mayor Graham Elmes who grew up on Springvale Station.

Now a state councillor for Agforce, Mr Elmes said the $7 million spent on the property was a "waste of taxpayers' money" and an "absolute joke".

"By the time the sediment gets from there to the Great Barrier Reef there's nothing left of it," he told ABC Radio Far North Queensland last month.

The ABC has since discovered that Mr Elmes and his wife are behind one of the applications to mine the West Normanby on Springvale Station for gold and tin, through their company Isabella Mining Pty Ltd.

7.30 asked Mr Elmes why he had not disclosed that he was seeking to mine on Springvale when criticising the state's purchase of the station.

"Mining has been going on in the area for the last 100 years," he said.

"We have regulations in place to make sure you're not contaminating the river, so we work 100 per cent to those regulations.

"As you take the material out you return the material from where it's come from and you don't let dirty water get into the main stream of your river."

Kings Plains station is downstream from Springvale. ( Supplied: Kerry Trapnell )

Tim Hughes is a director of the independent and not-for-profit South Endeavour Trust, which has bought Kings Plains station downstream of Springvale.

The station is run both as a grazing enterprise and a nature reserve, with extensive work being done to stem sediment flowing from the property, down the Normanby system and onto the reef.

Mr Hughes wants the applications to mine on Springvale refused.

"Why are taxpayers giving us money to reduce sediment? Giving other people money to reduce sediment?" he asked.

"Why are hundreds of millions of dollars being spent on reducing sediment if we're actually providing for other people to create sediment for very, very small private gain and no public benefit? I don't understand it."

Mining applications subject to 'rigorous' assessment

The Department of Natural Resources and Mines told the ABC the in-stream mining applications on Springvale Station were going through a "rigorous and transparent" assessment process.

"This process determines whether applications meet strict environmental, public interest, appropriate land use, compensation, native title and technical requirements," a department spokesman said.

The department is also considering a third in-stream mining application for the Laura River further to the west. The Laura empties into the Normanby River which flows into Princess Charlotte Bay in the reef catchment.

"We get barramundi, catfish in [the river], and freshwater crayfish, turtles," said traditional owner Roy Banjo.

"There are heaps of cultural sites in the area. Where they're planning to mine there are some artefacts there."

"This mining is essentially a third-world kind of country practice operating in a first-world country," said Dr Shellberg of the Australian River Institute.

"Many other countries have banned this kind of mining because of its direct impact on river health and downstream ecosystems."

The ABC contacted the North Queensland Miners Association which represents alluvial miners, but it declined to comment on the applications to mine the West Normanby and Laura Rivers.