Case Study—King River Delta

“Where for the first time ever in Tasmania, we’ve had proper and natural vegetation cover in a tailings environment”

For more than a century, 100 million tonnes of tailings and slag containing heavy metals and other elements from the Mt Lyell mine had been dumped into the Queen and King Rivers.

In some places, the contaminated sediment on river beds and banks is more than 100 metres thick and a tailings delta (essentially a large artificial beach) had formed at the mouth of the King River.

The river delta covers about 3.5 square kilometres and major toxic contaminants included arsenic, chromium, copper, lead, mercury, nickel, selenium and zinc.

In 1994 the dumping stopped but the discharge of acid mine drainage water from Mt Lyell into the river and harbour is expected to continue for the next 600 years.

Virotec was selected as the preferred technology provider from successfully treating and revegetated mine waste rock and tailings at the Rossarden Mine in eastern Tasmania.