Schalk Burger | Mining Weekly
In its 2014 session, held in February, world regulatory body the International Seabed Authority’s (ISA’s) Legal and Technical Commission was preparing draft regulations for the exploitation of polymetallic nodules in three areas approved for deep-seabed exploration worldwide. The first of the awarded exploration licences will expire in 2016.
The ISA has, thus far, granted 14 of its 166 member States exploration licences in these three areas. Five other exploration plans have been approved, but have not yet been concluded in the form of a contract, while a further seven exploration plans are being considered by the ISA Legal and Technical Commission.
In one of the three deep-seabed exploration areas currently permitted by international law, China, South Korea, Germany and India are among the States prospecting for polymetallic nodules and sulphides in the Central Indian basin and the Indian Ridge, far to the south-east of South Africa.
They are part of the international seabed mining exploration projects looking for polymetallic nodules along enormous undersea ridges, vast abyssal plains and geological fault lines in the Central Indian basin of the Indian Ocean, north-east of Mauritius and Réunion; and in the Equatorial North Pacific Ocean, south-east of Hawaii. Meanwhile, exploration for polymetallic sulphides is being undertaken in the Mid-Atlantic Ridge of the Atlantic Ocean and in the Southwest Indian Ridge, south of Madagascar.
Polymetallic nodules are deposits or accretions partially buried in deep-seabed sediments that contain manganese, nickel, cobalt and copper. Polymetallic sulphides often precipitate from deep-sea hydrothermal vents found along the mid-ocean ridges and contain copper, zinc, lead, gold and silver. Deep-seabed mining licences to explore for cobalt sulphides, manganese nodules, polymetallic sulphides and cobalt-rich ferromanganese crusts have been awarded to various international mining companies.
Further, commercial companies have been granted rights by several countries, including Ghana and Papua New Guinea, to mine the seabed in their exclusive economic zones for gold, silver, zinc and copper using dredging, mining and oil and gas equipment and techniques.
In Southern African waters, diamond company De Beers, coastal mining company Panda Marine and South African State-owned Alexkor mine diamonds from the coast and seabed on the West Coast.
Off the coast of Papua New Guinea, Canadian deep-seabed miner Nautilus Minerals – the first company to receive an ISA exploration licence – found that indicated mineral resources are 7.2% copper, 5.0 g/t gold, 23 g/t silver and 0.4% zinc, while inferred mine- ral resources are 8.1% copper, 6.4 g/t gold, 34 g/t silver and 0.9% zinc.
In its technical study towards developing a regulatory framework for polymetallic nodule exploitation, the ISA reports that “the renewed interest in the potential for commercial exploitation of deep-seabed polymetallic nodules is driven by an increase in demand for metals, a rise in metal prices and a decline in the tonnage and grade of land-based nickel, copper and cobalt sulphide deposits, as well as technological advances in deep-seabed mining and processing”.
History of Seabed Mining
In the past, seabed and subsoil beyond the limits of national jurisdiction were considered unregulated territory until the United Nations declared them the common heritage of human- kind in 1970. Since the 1982 United Nations Law of the Sea, the seabed can only be subjected to mining “for the benefit of all human- kind”, in accordance with the founding charter of the ISA.
Nevertheless, the ISA states: “Seabed mining has a smaller footprint and uses a more environment-friendly process than terrestrial mining. It does not impact [on] waterways, has reduced carbon emission, as a result of limited heavy machinery with less overburden, meaning a smaller volume of nonvaluable rock is removed and disposed of before the resource is exposed.”
Seabed mining also does not require additional roads, surface ore transport systems, buildings or other permanent infrastructure that could disrupt indigenous or native populations or habitats.
However, the ISA reports that the potential impact on the marine environment includes the removal of organisms and their habitats along with the mineral deposits and the smother- ing of adjacent communities by any sediment plume that may be created. “Exploration and exploitation must be carried out with minimal environmental impact.”
Meanwhile, the ISA has funded research projects to examine the potential impact of seabed mining and how to assess and mitigate these effects. Exploitation regulations will include obligations and recommendations to reduce any potential environmental impact, the organisation states.
Regulations for limited sampling exploration in international waters include significant environmental and deep-sea chemosynthetic ecosystem monitoring and management obliga- tions. State companies conducting exploration must collect baseline environmental data during this phase and during exploitation to develop their environmental monitoring plans and to determine the environmental impact of exploitation. The data must be analysed to improve understanding of the cumulative environmental impact of all aspects of exploitation.
Analysis of the data collected in the environmental monitoring programmes during exploitation will provide important feedback to, and inform potential modification of, environ- mental monitoring plans and systems. The ISA aims to establish exploitation regulations that will be modified and improved as it receives feedback from environmental studies during exploitation.
“Because exploitation will not be a public enterprise, questions immediately emerge about how to appropriately divide both profit and risk. These, in turn, raise difficult resource rent questions about capturing windfall profits and rents in the name of social justice. Both environmental destruction and the division of rent must somehow be addressed in the eventual fiscal package,” the ISA warns.
Mining Techniques and Environmental Concerns
There are several deep-seabed mining techniques, depending on the mineralisation of the resource. Some companies use a seabed-crawler machine that pumps the mineral-bearing gravels to the surface.
Other techniques use cutting machines, similar to those used for coal mining, that cut mineral-bearing rock on the seabed before the resultant sand, gravel and silt are collected by another machine and pumped as a seawater slurry to a production support vessel on the surface. Processed materials are then returned to the deep-sea area being mined.
However, the techniques may increase turbidity of the water column in the area of exploitation and may negatively affect the filter- feeding benthic organisms living on the seabed at extreme depths.
Coastal alluvial diamond mining company Panda Marine claims that marine mining has a low environmental impact, when practised responsibly, and the disturbance of the seabed and soils release nutrients that provide an additional boost to native animal populations, especially zooplankton that can help to boost the depleted Atlantic fish stocks off the western coast of Southern Africa.
Canadian marine miner Marine Mining Corp, exploring for gold off Ghana’s coast, notes that its operations require no chemical alteration of the rocks – the sands are brought up to the surface, gold removed by gravitational separation and the remaining materials returned to the seafloor.
Marine Mining says a review of similar ope- rations around the world reports little or no environmental concerns, even off heavily popu- lated and monitored beaches, such as Florida.
“In addition, the company has been investigating existing environmental problems on the coast to see whether mining operations can be tailored to ameliorate them. Many points along the coast have been modified to suit the tourist industry, and one of the results has been coastal erosion, which now endangers a number of villages. An offshore mining project may pump offshore sands to the beach to replenish them, or gravels and boulders to buffer them,” highlights Marine Mining Corp exploration manager Michael Gipp.
De Beers Marine Mining, mining off Namibia’s coast, carries out daily environmental management at an operational level and ensures legal compliance on environmental obligations.
The ISA Marine Mining Code notes that, despite States having explicit marine environmental obligations, there is little national environmental regulation of marine mining, especially beyond the territorial sea. Further, other than the ISA’s marine environmental work related to marine minerals exploration and exploitation in the areas being explored, there is none in any marine area beyond national jurisdiction.
“By developing and promulgating the code, the marine mining industry is assuming a share of the extensive responsibilities for marine environmental protection that are assigned under international law to States. The code also enables the marine mining industry to meet the requirements for regulatory predictability and reduction of risk, including environmental regulations and risks, and in facilitating financial and operational planning,” the ISA notes.
Further, a critical problem is “high grading” that, while not allowed, is “an all too frequent practice” involving a mining operation targeting only high-grade portions of reserves to maximise profits and minimise expenses, leaving significant, but lower-grade, portions behind in their concession areas.
Therefore, the ISA says: “A ‘whole of the deposit’ approach to nodule exploitation is required that includes a comprehensive resource and reserve assessment of the proposed mining area and the adoption of a sequential mining plan that maximises reserve recovery, utilisation and metal recovery.
“Provision for periodic review and update of the mining plan must be made and performance guarantees and ‘failure to perform’ penalties, with the latter escalating over time to discourage behaviour inconsistent with approved mining plans, must be included in the regulatory framework for polymetallic nodule exploitation.”
The ISA technical study for exploitation regulations recommends a phased licensing approach to grant three-year fixed-tenure mining licences to companies, which will improve the accountability of companies throughout deep-seabed mining operations through periodic review and analysis of performance.
Proposed regulations for exploitation include granting provisional mining licences after receiving detailed bankable feasibility studies, which must be preceded by a pilot mining ope- ration to prove economic, environmental and technical analyses done during exploration.
“An application for a tenured mining licence would include the data, information, analysis and conclusions of the detailed bankable feasi- bility study and full environmental-impact assessment and proposed work plans. This will provide data, information and analysis allowing the ISA to determine whether a full-scale mining operation could be undertaken in an acceptable and minimally environmentally invasive way,” the authority concludes.