Digging Deep: An Integrated Approach for Assessing the Impacts of Deep-sea Mining

Thomas Peacock, Professor of Mechanical Engineering
Pierre Lermusiaux, Professor of Mechanical Engineering
Glenn Flierl, Professor of Oceanography


Year One Report Executive Summary

This project is performing physical oceanographic and biological modeling in order to support the assessment of the potential impacts of deep-sea mining activities, which are to commence in 2018 in the Bismarck Sea and after which there is likely to be widespread proliferation throughout the global oceans. Our investigations are covering several aspects of the process, including: (i) Developing analytical modeling of the characteristics of mining dewatering plumes that are expected to be produced; (ii) Numerical modeling of mining dewatering plumes; (iii) Regional oceanographic modeling of the proposed Solwara mining site in the Bismarck Sea; and, (iv) Biological modeling for integration with the physical oceanographic modeling. Furthermore, we are pursuing an ambitious plan to perform the first dedicated field studies of dewatering plumes in either 2017 or 2018. At present,we have developed the analytical plume model and performed some associated biological modeling. We recently participated in the 2016 Ventbase Mining Plumes workshop, for which we will contribute to a working document on plume modeling for submission to the International Seabed Authority.


Proposed Work

seafloor

One of the pressing environmental questions facing the ocean is the potential impact of the proliferation of deep-sea mining activities. It has long been determined that the sea floor possesses vast untapped resources of rare metals but only recently have they become economically viable. As such, preparations are now underway at the Solwara 1 site off Papua New Guinea (figure 1), with operations currently scheduled to start in 2017. Although the proposed operations seem sound, there is some concern, that the physical oceanographic and flow transport modeling performed to date is insufficient to rigorously assess the impacts of the project. Of particular concern is whether upwelling and currents could carry pollutants up out of the deep sea, or from spills and leakages into marine food chains where they may poison marine species and the humans that eat them. All of these impacts need to be further quantified and studied.

The focus of this proposal, therefore, is to kick-start an initiative at MIT to assess the impacts of deep-sea mining by developing a high fidelity, regional, physical-biogeochemical oceanographic model of the Bismarck Sea. The latest Lagrangian data processing and nonlinear dynamical systems tools will be used to understand three-dimensional flow transport in the region, in order to provide a clearer understanding of the fate of material released by the mining activities at different depths and locations. The project brings together three MIT faculty with complementary expertise in numerical ocean modeling, dynamical systems methods for flow transport, and modeling of ocean-biological systems. We consider this to be a nucleus of a team that, based on the outcomes of this project, can grow over the next few years to encompass a wider scope, and involve other researchers at MIT and WHOI. The tools we implement and develop can be applied to assess the environmental impact at any proposed location for the growing field of deep-sea mining.

Seafloor production system

FIGURE 1: (ABOVE) THE SOLWARA 1 DEEP-SEA MINING PROJECT (RED RECTANGLE) LIES IN DEPTHS OF 1600M OFF THE COAST OF PAPUA NEW GUINEA, BETWEEN NEW BRITAIN AND NEW IRELAND. (RIGHT) THE NAUTILUS SEAFLOOR PRODUCTION SYSTEM (SPS) INVOLVES SEAFLOOR CUTTING, A RISER AND LIFTING SYSTEM, AND SHIPBOARD OPERATIONS (IMAGE: NAUTILUS MINERALS).