With the current known mineral deposits on land increasingly being depleted globally, necessitating greater exploration, interest in deep-sea minerals is growing as mining companies look for future sources to exploit.

“The ocean is where future resources exist,” India Council of Scientific and Industrial Research National Institute of Oceanography chief scientist Dr Rahul Sharma said at South Africa’s Council for Geoscience Annual Conference 2017, earlier this month.

Sharma highlighted that minerals from the deep seafloor, such as polymetallic nodules, ferromanganese crusts and hydrothermal sulphides, are potential sources of millions of tonnes of metals such as copper, nickel, cobalt, manganese and iron.

He highlighted that, with up to 0.358-million tonnes of metals mineable a year, with a value of about $963-million, or $18.73-billion, in 20 years, seabed mining was an attractive mining method.

Exploration licences have been acquired from the International Seabed Authority under the United Nations (UN) Law of the Sea over large tracts of the seafloor in the Atlantic, Pacific and Indian oceans in areas beyond traditional national jurisdictions.

Sharma noted that the research and development of technology for environmental studies and mining and exploration were also well under way in preparation for eventual deep-sea mining projects.

Until 2010, only eight contractors had been allotted areas for exploration in international waters by intergovernmental body the Interoceanmetal Joint Organisation, established in 1987 with the objective of exploring, prospecting and exploiting polymetallic nodules in accordance with the 1982 UN Convention on the Law of the Sea.

Six contractors, from France, Russia, Japan, China, Korea and Germany, have been allowed to conduct exploration work in the Pacific, while India has laid claims in the Indian Ocean. Subsequently, many others, including Nauru, Tonga, Kiribati, the UK and Belgium have laid claims in the Pacific Ocean for polymetallic nodules.

Since 2010, China, Korea, India, Russia and France have also staked claims in the Indian and Atlantic oceans for hydrothermal sulphides.

SOUTH AFRICA
In South Africa’s exclusive economic zone (EEZ), Sharma highlighted, there were many areas available for companies to claim for exploration purposes, with significant areas of ferromanganese crust between South Africa and Madagascar.

Government’s Operation Phakisa: Ocean Economy plans to unlock the economic potential of the country’s marine environment through the rapid promotion of marine petroleum and minerals extraction.

Currently, 98% of South Africa’s EEZ has been leased for offshore oil and gas exploration. Operation Phakisa aims to fast-track the drilling of 30 wells in the next ten years and develop infrastructure such as a phased gas pipeline network.

Government has further granted rights for a range of other industrial practices, including offshore mineral sands mining and unconventional gas exploration such as offshore hydraulic fracturing, or ‘fracking’.

Three mining rights have also been granted, in 2012 and 2014, by the Department of Mineral Resources to Green Flash Trading 251, Green Flash Trading 257 and Canadian company Diamond Fields International to prospect for marine phosphates, predominantly used for fertiliser production, on claims covering more than 150 000 km² or 10% of the country’s marine environment.

ENVIRONMENTAL IMPACT
To date, no other country has permitted seabed mining in its EEZ, with considerable resistance to these project proposals. In most cases, governments have opted for a cautious approach in the form of a moratorium, permanent bans or refusal of project proposals, says South African environmental watchdog the Centre for Environmental Rights (CER) legal campaigner Saul Roux.

There will be an environmental impact, said Sharma, noting that many organisms on the seafloor would not survive, owing to sediment plume, the change in the chemical characteristics of the water column and the impact on surface photosynthesis.

Seabed mining requires dredging up the top 3 m of the marine floor, destroying critical, delicate and insufficiently understood sea life.

In South Africa, marine phosphate would require an environmental-impact assessment (EIA). The International Seabed Authority is in the process of developing environmental management regulations for mining in areas beyond national jurisdiction.

However, Roux says it should not be that easy.

There is relatively limited knowledge on the impact of bulk marine sediment mining on marine environments. However, preliminary assessments, undertaken in other countries, outline considerable and irreversible consequences for marine ecosystems and fishery resources, signifying the need for longer-term investigations. These studies note that the likely devastating effects of bulk marine sediment mining, coupled with a lack of knowledge on the method, warrant extreme caution.

Prior to the Green Flash Trading prospecting rights being granted, the World Wide Fund for Nature-South Africa (WWF-SA) commissioned a report on the potential impact of marine sediment mining on the west and south coasts of the Western Cape. The report found that bulk marine sediment in the Green Flash Trading prospecting areas would have a severe and potentially irreversible impact on seabed habitats. The destruction and permanent alteration of marine habitats would be inevitable in light of the type of mining proposed.

The list of potential consequences outlined include the direct destruction of seabed ecosystems, which are the building blocks of marine ecosystems, and the release of hazardous substances such as radioactive materials, methane, hydrogen sulphide and heavy metals locked in the seabed.

Further, seabed mining could lead to the direct destruction of spawning, breeding and feeding habitats for fish species, many of which are commercially important, locally and internationally. Habitat destruction and resultant ecosystem changes in mined areas could also be permanent, as recovery to predisturbed states would occur only on geological time scales.

The report found that marine phosphate mining could have significant and irreversible effects on biodiversity, ecosystem functioning and fishery resources.

In particular, the prospecting rights for marine phosphate mining in South Africa’s EEZ directly overlap with critically endangered ecosystems, ecologically and biologically significant areas and habitats earmarked for protection under another Operation Phakisa initiative designed to establish a network of marine protected areas. Some of the benthic habitat types that coincide with the prospecting areas also do not exist anywhere else, emphasises the CER.

In 2015, a group of organisations that shared the common interest in pursuing a cautious approach towards seabed mining formed a coalition. The Safeguard our Seabed Coalition includes organisations that represent the interests of commercial and small-scale fishing, organised labour, and environmental and environmental justice organisations. The Safeguard our Seabed Coalition is calling for a moratorium, or ban, on marine phosphate mining in South Africa.

In Namibia, for instance, there is already a moratorium on marine phosphate mining, while in New Zealand the first marine phosphate mining application made to the Environmental Protection Authority was refused in 2014.

Looking ahead, Sharma noted that there was still much to be done before seabed mining became a significant commercial enterprise. He noted that governments and agencies alike would need to look at capacity building programmes.

This would include marine surveys undertaken through interdisciplinary research and further EIAs on the impact marine minerals exploration could have on the ocean’s ecosystems and biodiversity.

SOCIOECONOMIC IMPACT
As seabed mining would have significant repercussions on fish stock, it would also impact on the revenue, jobs and livelihoods associated with the fishing industry, Roux notes, adding that it is important that the socioeconomic contributions of fishing are understood and considered in decision- making on seabed mining.

South Africa’s commercial fishing industry employs about 27 000 people directly and 100 000 people indirectly. In the Western Cape, where the country’s prospecting rights are concentrated, the fishing industry contributes about 2% to gross geographic product.

The marine phosphate prospecting areas directly overlap with fishing footprints of several fisheries, including hake longline, tuna pole, west coast rock lobster, small pelagics and the chokka squid sector.

“Notably, the prospecting rights coincide with South Africa’s only Marine Stewardship Council-accredited fishery, which employs 12 000 people and generates R4-billion in revenue a year,” says Roux.

This industry has operated for almost 120 years, creating thousands of jobs. As a renewable industry, it could continue to do so in perpetuity, provided that its trawling grounds are not destroyed by seabed mining.

Further, the latest estimates suggest that there are around 8 078 fishers in South Africa, with the Western Cape home to 1 667 of them. “Small-scale fishers directly rely on healthy marine ecosystems for their livelihood, nutrition, food security and income and this sort of fishing plays a critical role in providing employment and access to protein in coastal communities.

“Marine phosphate mining will likely have a considerable detrimental impact on tourism, particularly coastal and marine tourism. Bulk marine sediment mining requires additional coastal developments that have associated consequences. These include desalination plants, beneficiation facilities and processing plants, as well as increased shipping,” Roux highlights.

DEEP-SEA MINING CHALLENGES
Sharma noted that, besides mining operations taking place about 300 days a year, seabed miners will also have to face extreme working conditions, including temperatures of around 1 ºC, pressures of about 300 to 500 bars, cross-cutting currents, uneven topography and heterogeneous mineral distribution.

Further, miners will have to make do with working in an environment that has no light, at depths of about 5 km below surface and being thousands of kilometres from the shore.

He highlights that, for these reasons, mining companies should invest in self- propelled mining devices that could detect promising targets, allowing for better power consumption and cost and time savings.

Mining companies should also consider screening the ore at seabed level, instead of pumping it up to the surface.