The seabed mining company, Nautilus Minerals, says its world first operation to mine in Papua New Guinea's Bismarck Sea will not discharge any waste into the ocean.
The company hopes to start mining on the sea floor by 2018, despite strong opposition from environmental activists and calls for caution from the scientific community.
But Nautilus' chief executive Mike Johnston says his company has been conducting environmental impact studies since 2006.
He says the results have consistently shown the effects of the operation on the marine environment will be minimal.
"The total area directly impacted by mining is less than point one of a square kilometre. Impacts that are expected from the mining projects do not extend outside the mining lease. There are no tailings associated with our seafloor mining project which is pretty much unheard of for mining."