From Paul Greisman, URS
I was greatly disappointed by the misconceptions in your piece on mine tailings
(11 November 2000, p 46).
It states, for example, that the Batu Hijau mine discharges tailings into a
local bay. This is not true. We specified an outfall 3 kilometres long that
would discharge at a depth of 125 metres. The discharge point was sited at this
point to allow the negatively buoyant slurry to flow as a turbidity current
under water, down steep slopes into a canyon and onward to depths exceeding 3000
metres. We applied a numerical model to predict the flow, deposition and
resuspension of tailings. The measurements to date support the predictions of
the model.
Most scientists agree that submarine tailings disposal is environmentally
superior to storage on land.
Vancouver, Canada
