An audit found that the method also met the requirements of the relevant technical agencies.

Department of minerals and geoscience director-general Zamri Ramli said this in a statement today when commenting on media reports about uncontrolled REE mining in the area potentially causing landslides.

He said this mining technology involved minimal land clearing and tree felling.

Zamri said this method used a low-concentration of ammonium sulphate solution that was injected into the soil to extract rare minerals through an ion exchange reaction.

The minerals flow through a piping system and are collected at the foot of the hillside for the next process.

This would not cause disturbances in the stability and cohesive force of the soil, he added.

“The in-situ leaching mining method carried out in ion-adsorption clay surfaces can only be implemented for REE minerals found above the groundwater level.

“This is to guarantee the effectiveness of the targeted leaching process and to avoid contamination of the groundwater,” he said.

Zamri said as a control and mitigation measure for groundwater pollution, monitoring wells were dug in several strategic locations to detect the possibility of leakage.

He said a specific procedure was also outlined to control pollution, such as a flushing method to stop the further flow of pollutants.

“In conclusion, NR-REE mining using this in-situ leaching method is the latest sustainable method where the impact on the environment can be controlled.

“It offers low operating cost and a good level of worker safety,” he said.