Seabed
Mining
Seabed mining is an experimental industrial field, which involves extracting submerged minerals and resources from the sea floor.
What is seabed
mining?
Seabed mining is an experimental industrial field, which involves extracting submerged minerals and resources from the sea floor, either by dredging sand or lifting material in any other manner. Globally and in New Zealand, sand has been the primary target; primarily for use in construction but recently, for replenishment of urban beaches.
Where is it happening?
Right now, there is no actual seabed mining in Aotearoa. There is, however, sand mining.
What's the difference? Sand mining involves dredging sand and taking it away for use to fill other beaches, to make concrete, etc. It's highly destructive.
Seabed mining involves digging up the seabed, extracting the minerals - usually on board a ship - and then dumping the majority of the waste back onto the seabed. This causes far more damage than sand mining, because it leaves sediment hanging in the water column, as well as creating "dead zones" on the seafloor.
The ironsands off the west coast of the North Island of New Zealand, are a unique geological and marine environment, currently in the crosshairs of global mining companies looking to exploit their high iron content and low extraction costs.
Sand mining sites of significance in New Zealand include the Kaipara Harbour (primarily for construction sand), and Pakiri Beach for concrete and the replenishment of Auckland’s beaches. These operations have been traditionally carried out in shallow depths (up to 25 metres), by suction dredges pumping sand onto barges.
What are the impacts?
Much of the science around the environmental impacts of all these emerging ideas is incomplete and unproven. The common consequence of all types of operations is the obliteration of any marine life in the mined area and in surrounding areas due to the smothering effects of the plume created when unwanted matter is released back to the sea floor.
Impacts from seabed mining cause erosion, destruction of ecosystems and destroy habitats of endangered species.