Yeelirrie proposal puts subterranean fauna at risk, says EPA

Cameco's proposal for uranium mining at the Yeelirrie deposit should not be given the go-head because it does not adequately protect underground fauna, the Western Australia Environmental Protection Authority has recommended to Australia's minister for environment.

Cameco's proposal for uranium mining at the Yeelirrie deposit should not be given the go-head because it does not adequately protect underground fauna, the Western Australia Environmental Protection Authority (EPA) has recommended to Australia's minister for environment.

Yeelirrie (Image: Cameco Australia)

An environmental scoping study for the shallow Yeelirrie deposit submitted by former owner BHP Billiton received approval from the Western Australia EPA in 2010. Cameco purchased Yeelirrie from BHP Billiton in 2012. In November 2014, Cameco submitted a new proposal to the EPA to mine up to 7500 tonnes of uranium oxide concentrate per year at Yeelirrie over 22 years - a greater quantity over a shorter period than foreseen in BHP Billiton's proposal. The uranium oxide concentrate would be transported by road to the port of Adelaide for export.

Cameco's proposed two open-pit mines at Yeelirrie would total some nine kilometres in length, be up to 1.5 km wide and up to 15 metres deep. Their construction would involve the direct disturbance of 2422 hectares of land. The open pits would be dewatered, mined and backfilled progressively throughout the life of the mine. The ore and waste rock would be stockpiled near the open pit. Ore would be processed within the metallurgical plant using an alkali tank leaching process, and waste rock backfilled into the pit.

The EPA announced today that it has completed its environmental impact assessment on Cameco's proposal and has submitted recommendations and advice to the environment minister.

"Of the nine [key environmental] factors assessed, one - subterranean fauna - was unable to meet the EPA's environmental objectives," the agency said. "The other eight factors, including potential impacts to flora and vegetation and to human health, as well as rehabilitation and decommissioning, met the objectives."

It said, "The proposal has the potential to directly impact subterranean fauna by the removal of habitat during mining and temporary removal of habitat (stygofauna) during dewatering."

Cameco said more than 850 samples have been taken from the Yeelirrie project area, which has identified 73 species of stygofauna - fauna which occur below the water table. Of these, 11 species are currently only known from the impact area.

The EPA said it was of the opinion that "there remains too great a chance of a loss of species that are restricted to the impact area and therefore considers that the impact is such that the proposal should not be implemented".

However, it recommends that if the minister allows Cameco to go ahead with the Yeelirrie project, "appropriate conditions" regarding the impacts on subterranean fauna should be imposed.

"Uncertainty surrounding the potential for serious or irreversible damage to subterranean fauna species may be mitigated by further scientific investigation, research and study to determine if the restricted species either extend beyond the impact area of the proposal, or a compelling case is made that their habitat is continuous and extensive well beyond the impact area," the EPA said.

"An industry-funded research program with the long-term aim of reducing uncertainty surrounding the conservation of subterranean fauna species in the presence of mining may assist with improving the currently limited scientific understanding of subterranean fauna across the state and inefficient sampling methods," the EPA suggested. "A commitment by the proponent to support such a program could potentially and indirectly offset the local impacts it might have on subterranean fauna at Yeelirrie to the broader benefit of subterranean fauna conservation state-wide."

In a statement, Cameco said it "respects the findings of the EPA and acknowledges the complexity and uncertainty involved with assessing subterranean fauna".

Cameco Australia managing director Brian Reilly said, "Sampling and impact management for subterranean fauna at Yeelirrie is very complex and this is reflected in the EPA's findings. We believe that with further sampling and research, subterranean fauna can be appropriately managed at Yeelirrie and we will work with government agencies and stakeholders to find a way forward."

Yeelirrie has 127.3 million pounds U3O8 (49,000 tU) of measured and indicated uranium resources, with an average grade of 0.16% U3O8.

Researched and written
by World Nuclear News