Marine Geospatial Ecology Lab

Present and future of Regional Environmental Management Plan for Seabed Mining in Areas Beyond National Jurisdiction

Present and future of Regional Environmental Management Plan for Seabed Mining in Areas Beyond National Jurisdiction (ABNJ)

By Elisabetta Menini, PhD Student in Marine Science and Conservation, Nicholas School of the Environment, Duke University.

The world has been talking about deep seabed mining since the 1970’s when the process to establish the United Nation Convention of the Law of the Sea (UNCLOS) began. Currently, it is one of the strongest international legislative documents ratified by 168 countries. Among the detailed description of rights and duty of its member States in the marine space and environment, it established the International Seabed Authority (ISA) to manage the human activities (deep seabed mining in particular) in the “Area” defined as the soil and subsoil found in international waters beyond 200 nm from the cost (Kim, 2017). The Area and its resources (living and non-living) are defined as common heritage of humankind and are the place of the vast and most unknown environment in the marine realm: the deep sea (below 200 m depth) (Danovaro et al., 2017). 

The three types of existing mineral resources found in the deep sea are the focus of interest of deep seabed mining: the manganese nodules are mineral conglomerate potato-size structures; the cobalt crusts on seamounts, are present as a dark thick layer on a hard rock substrata and the massive sulfide deposits are formed by precipitation of the metals contained in hydrothermal fluids (fig 1). All three type of these deep-sea mineral resources contain precious and rare metals including zinc, cobalt, manganese, copper and gold, which are used in products such as phones and batteries, and “green technologies” such as electric cars and solar panels. Several mineral resources are becoming more difficult to find and extract on land, and the only remaining frontier is believed to be the deposits found in the deep sea. Alternative sources such as metal recycling, are not considered sufficient for the growing marked demand for minerals (Beaulieu, 2017).

Figure 1. (a) Manganese nodules on abyssal plain with an (NOAA, 2019); (b) cobalt crust (World Ocean Review, 2014); (c) sulfide deposits on chimneys of hydrothermal vents (photo credit: Nautilus Minerals, form Parkins, 2014).

Deep seabed mining is a very controversial topic, especially among scientists studying life in the deep sea. Most of the mineral resources are found in areas that often coincide with areas rich in biodiversity. Therefore, if the industry eventually moves forward, a large amount of known and unknown creatures will likely perish. Many manganese nodules are actual substrate for different organisms. Cobalt crusts can be populated with deep sea corals and sponges, and the massive sulfide deposit on hydrothermal vents are one of the most prolific habitats in the deep sea. A high loss of biodiversity will be inevitable if seabed mining happens. Each stage of the practice will have an high impact on the environment: scraping the minerals will modify substrata forever; toxic substances and particulates from extraction will be dispersed in the water column, the noise of the machines and pumps that will be used to transport the material to the surface will disturb marine life; additionally, light will likely disturb different marine organisms since they normally live in the dark (Gollner et al., 2017).  Most of the animals inhabiting the deep sea live for hundreds of years and reproduce very rarely (corals for example). Consequently, the impact of seabed mining could bring to local extinction of deep-sea organisms (Gollner at al., 2017; Van Dover et al., 2018).

The International Seabed Authority (ISA) is the intergovernmental organism created to manage the seafloor in ABNJ and is leading the establishment of Regional Environmental Management Plans (REMPs) to manage seabed mining activities and to protect the Environment from harmful effects. Currently, there are 18 contracted exploration areas for Polymetallyc Noduls between the Pacific Ocean and Indian Ocean, 7 for sulfide deposits on the Mid-Atlantic Ridge and on the South-West Indian Ridge, and 5 for cobalt crusts in the north West Pacific. These contracted areas will be managed through REMPs. Currently, the only REMP in place is on the Clarion Clipperton Zone (CCZ) in the Pacific Ocean. Here, the abyssal plain rich in polymetallic nodules is currently being explored. Within the CCZ REMP, nine Areas of Particular Environmental Interest (APEI) of 200 km x 200 km are established to protect the benthic environment (Wedding et al, 2015).

The next REMP that may be establish in the near future is the one on the Mid-Atlantic Ridge. Here, there are contracted exploration areas for massive sulfide deposits along the axis of the ridge, by the Government of Poland, the Government of France with Ifremer, and Russia. The main interest seems to be directed to the inactive vents fields which are characterized by the absence of highly dense biological assemblages (Van Dover, 2019). However, 11 active vent fields, that are rare and unique habitats for numerous vents obligates species, are included in the contractor’s exploration areas and it still undetermined if they are going to be future target for the exploitation of mineral resources. The scientific community is advocating to protect active vents fields from mining activities for years, which highlights the importance of this habitat in the deep sea. They are also collaborating with the ISA in science-based workshops to provide information for policy makers. These workshops, where MGEL played an active role as facilitator and as provider of technical assistance and scientific and spatial information, happened throughout 2019 and 2020 (Clearly et al. 2019, ISA 2019). The decision-making process for the establishment of the REMP on the Area of the Mid Atlantic Ridge has been planned to be finalized before the end of 2020, but with the current pandemic caused by the virus covid-19 it might be delayed.

The regulatory framework to manage seabed mining is not quite ready, the studies on the impacts of seabed mining activities are still ongoing, and not all the Regional Environmental Plans have been approved. The spatial plan for the REMP on the Area of the Mid Atlantic Ridge is still under discussion, but it will likely take into consideration spatial measures and regulations applied at different scales (Dunn et al, 2018). The Mid-Atlantic Ridge is a very heterogeneous environment that needs a different approach than the process on the CCZ. There are different oceanographic characteristics that influence the biochemical and physical connections between habitats, which have to be reflected in the management plan.

The aim of the REMPs should be to balance the damages of seabed mining and the protection of the ecosystems, but the uncertainties are countless. No one has ever tested the mining procedures in international waters yet. More time and more scientific information is needed to better predict the effects of mining operations on deep sea biodiversity. The Law of the Sea clearly states that the deep-sea environment in ABNJ must be protected for the sake of humankind as a whole, and to date the conditions do not seems sufficient to respect this legal principle. However, the level of collaboration between ISA and the international scientific community is unprecedented and, despite the controversial topic, this is setting a new historical perspective on international collaboration for environmental management plans.


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