Minerals Report - International Seabed Authority

creates wealth but it can also create a very diverse and wonderful
spectrum of scientific opportunities.
SUMMARY OF THE DISCUSSIONS
During the discussions on the case studies in the development of
the Namibian offshore diamond mining industry, and in the development
of an environmental baseline in a large open-ocean system off southern
Namibia by De Beers Marine, the focus of participants questions were in
five areas. These were with regard to the productivity of the drills used in
offshore mining, the grades of deposits in production, the long-term
impacts from mining, the impact of plumes and tailings disposal on the
seabed on seafloor communities, the applicability of ISO 14001 to deep-sea
mining of nodules, sulphides and crusts, the comparative costs of using
manned versus unmanned vehicles for observations and measurements in
the deep ocean, and the cost of the environmental work undertaken so far.
Dr Corbett was asked about the productivity of the drilling
machines that he had described, in particular the quantity of ore recovered
per hour. He was also asked about the grades of the deposits that De
Beers is currently mining. In response, Dr. Corbett said that there has been
a lot of proprietary knowledge that has gone into developing this offshore
industry, new technologies, neo-science and also the security of the
product. He pointed out that the acquisition of data in the offshore
environment is a very expensive. As a result, he said that from a De Beers
Marine perspective it has to guarantee the security and confidentiality of
the commercial data that it holds and uses on behalf of its clients. He
therefore informed the workshop that he could not provide answers to
these questions since they the responses had to do with commercial data.
He did however say that the productivity of the drilling machines vary
quite significantly around the different types of terrain. He also said that
while he could not provide the workshop with the actual grades of ore
that is being mined, the grades are low and in some areas, comparable to
the type of grades that one would see in terms of the raised beaches in
Namibia that have been published.
A participant asked Dr. Corbett the area of the seabed mined each
year and the total area that had been mined so far in De Beers’ operations.
It was noted that since the mining process is locally destructive, mining
INTERNATIONAL SEABED AUTHORITY 661