Australia has rejected Putrajaya's bid to send back radioactive waste from Lynas' rare earth processing plant in Gebeng, Kuantan.

Western Australia's Mines, Petroleum, Energy and Industrial Relations Minister Bill Johnston (above) acknowledged that the best way to dispose of such waste was to return it to its place of origin, but said Western Australia would not accept the waste back from overseas.

The rare earth processed at Lynas' facility in Kuantan, dubbed the "Lynas Advanced Material Plant (Lamp)", originates from Mount Weld in Western Australia.

“Generally speaking, the best place for contaminated material is where it comes from, which in this case would be in the mine void, but we are not going to take mine waste back from overseas,” Johnston told The Australian.

Energy, Science, Technology, Environment and Climate Change Minister Yeo Bee Yin had required Lynas to ship its waste back to Australia as part of its licensing condition, in particular, the water leech purification (WLP) residue.

The Lynas facility produces two kinds of waste, namely radioactive WLP residue and non-radioactive neutralisation underflow (NUF).

Up to December last year, the accumulated WLP residue at Lynas' facility was 451,564 tonnes, while the NUF waste amounted to 1.113 million tonnes.

Lynas has sought to turn the NUF into commercial products, but pilot studies found that its use as fertiliser led to elevated levels of heavy metal in produce, albeit still within permissible levels.

However, a ministerial review committee also warned that the heavy metal levels could increase further if used in large quantities.

As for the WLP, Putrajaya would likely have to explore other alternatives after Australia has put on record that it won't accept the waste.

Yeo had stressed that her ministry would not allow unlimited accumulation of wastes at the Lynas facility in Kuantan.

However, other ministers, including Entrepreneurship Development Minister Mohd Redzuan Md Yusof, have disagreed with the approach, stating that Australia would not accept such a proposal.