A Close Look at Deep Sea Mining

The future of the mining industry is inherently unsustainable but mining corporations think they may have an answer to prolong their survival: the ocean floor.

Christian Noyce Portrait

By: Christian Noyce
2014 Summer Intern

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The future of the mining industry is inherently unsustainable but mining corporations think they may have an answer to prolong their survival: the ocean floor. Because of the high prices of rare earth metals, Nautilus Minerals has become the first company to choose to skip extracting what little low grade metals are left from our mountaintops and land, instead opting to sign a lease to recover higher grade rare earth metals from polymetallic nodules, manganese crusts, and sulfide deposits under water off the coast of Papua New Guinea. Polymetallic nodules include high amounts of nickel, copper, cobalt and manganese; manganese crusts contain mostly cobalt and some platinum; and sulfide deposits include copper, lead, zinc along with some gold and silver.

Nautilus Minerals Seafloor Production SystemThe Ethical Metalsmiths community advocates for responsible and just mining practices. EM tries to reduce the need and demand for newly mined metals through metal recycling projects such as Radical Jewelry Makeover. EM believes that the demand for gold and other metals can be met by the current supply and therefore we only support legitimate, minimal, responsible and just mining development.  As of now, deep sea mining does not meet all of those criteria.

EM members have traveled to see firsthand those criteria in Peru where EM members source FAIRMINED gold.  EM members observed the responsible practices and communicated directly with the local owners and member miners, and surrounding community.  As regards deep-sea underwater mining, we are strongly concerned about the environmental effects on the ocean ecosystems as well as the social and environmental impacts on the coastal communities caught up in Nautilus Minerals’ project plans. 

We know more about the moon than our oceans.  Only three people have visited the deepest part of the ocean but over 500 have been to space.  We have better maps of Mars than we do of our own ocean floor.  Despite hundreds of years of exploration, we have only covered about 5% of the ocean and biologists estimate that up to 5,000,000 marine species have yet to be discovered.  With $17.8 billion dollars spent on space exploration in 2013, and only $5 billion spent on oceanic exploration, it seems as though we should fund more oceanic research before deep-sea mining forces the extinction of species before we know what they are and what opportunities they offer mankind. (Figure 1 (above) Nautilus Minerals' rendition of their Seafloor Production System. Nautilus Minerals.)

Deep Sea Mining Greenpeace InfographicPolymetallic nodules, manganese crusts, and sulfide deposits, are also projected to be high in profit.  With decreases in technological prices and increases in metal prices, the practice of deep sea mining could soon become a reality, perhaps as soon as 2017.  This process entails large robotic machines, called Bulk Cutters, which weigh 310 tons and are being produced by the company Soil Machine Dynamics.  The robots will be sent down to the ocean floor to grind up ore and hydrothermal vents, where extremely exotic sea creatures such as giant tube worms (Riftia pachyptila) live, creating a rock slurry which is pumped up to a collector vessel floating at sea. (Figure 2 (above) Greenpeace’s rendition of Nautilus Minerals’ Seafloor Production System. Greenpeace.)

Giant tube wormsNautilus Minerals, the leader in deep sea mining, may potentially recover cleaner rare earth metals than current land based production methods do. Intensive research, planning, risk mitigation and the advances of technology hope to decrease environmental degradation.   The risk to the environment is far greater, however, in the form of large scale disaster.  EM fears the potential of large scale environmental disaster similar to the Deepwater Horizon oil spill.  During the spill, British Petroleum’s fail safes were unable to stem the flow of oil gushing out of the sea floor.  The prospects of a rogue tank-sized robotic vehicle on the ocean floor gobbling up ecologically diverse habitats concerns us here at EM and it sadly is not out of the realm of possibilities. (Figure 3 (above) - Riftia pachyptila "giant tube worms")

According to Nautilus Minerals, advances in Remotely Operated Vehicles (ROVs) make exploring for deep sea ore plausible and essentially safe.  Nautilus Minerals hopes to send the ROVs to cut and crush ore deposits on the sea floor.  The ROVs will then suck up the crushed ore like a gigantic vacuum bringing the ore slurry up through tubing to a support tanker much like the oil tankers we see today.  These tankers separate the sea water from the ore, pumping the used seawater back to the ocean floor.  The tankers discharge the ore into a transportation barge to be taken back to land and processed further.  Once on land, the processing portion is very similar to other land based mining organizations.

Though the treatment of the ore is similar once it arrives on land, the economic benefits are far different than land based mining.  Preliminary studies conclude that seabed ore is of a higher grade than land based ore. Nautilus Minerals’ potential site off the coast of Papua New Guinea are thought to have deposits that contain 6.8% copper compared to approximately 0.6% copper found in land based mining operations.  In other words, within every ton of oceanic rock there are more desired minerals as compared to a land based ton of rock, impacting less seafloor than if conventional production on land.  The amount of land destroyed by deep sea mining will be far less than conventional mining but it still creates major damage to a very diverse and densely populated habitat.  We project deep sea mining as a potential boom.  “In total, about 6,000 km of mid-ocean ridge in international waters are now being explored for potential seafloor mining.  In total, around 7.5% of the global mid-ocean ridge – the geological backbone of our planet- is now being explored for its mineral wealth,” says Dr. Jon Copley, a marine biologist monitoring the development of deep sea mining.  Imagine if 7.5% of the United States - approximately the size of Texas - were mined and inhabitable. Life would be different, just like life will be different for the diverse ecosystems where these companies will be mining.

Much of this life occurs at hydrothermal vents which spew extremely hot sulfuric acid, copper, gold and other metals out from the divergent plates of the earth’s crust.  These minerals sink back down to the seabed, creating mini volcanic-like structures out of the pure minerals.  To date, organizations have been licensed 1.2 million square kilometers of seafloor to be harvested by the likes of Nautilus Minerals.

The ROVs (Figure 4 (left) Computer generated image of Nautilus Minerals' Seafloor Production Tools) will remove some of the most biologically diverse and active vents and habitat on planet earth.  This concerns environmentalists even though the production area is much smaller than land based mining.  All that grinding and crushing of the vents will create noise pollution and large plumes of sediment that have the potential to spread over a larger area of habitat, impacting whales and possibly smothering other sensitive species in a larger swath of habitation.  Scientific research concludes that these ROVs will disturb and suspend 16% of the floor sediment in the surrounding water and predict it will take 20 years for sediment to regain its original density. This disturbance could destroy species’ environments and feeding grounds. Even after the slurry of ore is pumped up to the ship the environmental impacts do not stop.  The waste water is pumped back down to the ocean floor, and even if it is filtered prior to return, it could contain sedimentary particles and heavy metals that are harmful to ocean floor species and migrate to human consumption through seafood and shellfish and via water tables.

These environmental impacts potentially affect the individuals who need our support the most: the citizens of Papa New Guinea, Fiji, Tonga and other developing nations.  Even though Papua New Guinea has already taken a 15% stake in Nautilus, contributing $120 million, they will most likely receive minimal profits or benefit from the large Canadian, American and other industrialized nations’ companies that float the enormous capital needed to fund these research-intensive, environmentally-problematic, and technically-demanding projects. (Figure 5 (below) Nautilus Minerals’ Location of Tenements map. Mineral Policy Institute.)Map of deep sea mine claims

With the large potential for profit as well looming environmental degradation, Ethical Metalsmiths watches carefully the movement of this burgeoning industry.  While deep sea mining seems appealing with regards to pushing the technological boundaries of mankind and exciting to those more profit driven, we caution against the unintended consequences of large, corporate, deep-sea mining operations.  EM advocates that Nautilus Minerals wait for the establishment of international environmental guidelines from the United Nations and the International Seabed Authority before beginning deep sea mining operations.

About the Author:

Christian Noyce is a senior of Grinnell College in Grinnell, IA studying economics and general science-physics. At Grinnell he co-directs the student government’s environmental committee where he analyzed the college’s environmental curriculum’s strengths and weaknesses to determine the appropriate approach towards an environmental studies major, advocate for sustainable living on campus through educational programming, and maintained composting and plastic bag recycling drives.  Christian has studied learning behaviors of environmental tourists on the ground in Costa Rica and has explored the environmental history of the United States.

FIGURES: Figure 1. Nautilus Minerals' rendition of their Seafloor Production System. Nautilus Minerals.
Figure 2. Greenpeace’s rendition of Nautilus Minerals’ Seafloor Production System. http://www.greenpeace.org/international/Global/international/photos/oceans/2013/seabed-mining/DSM-infographic.jpg. Greenpeace.
Figure 3. Riftia pachyptila (http://oncirculation.files.wordpress.com/2012/06/tubewormsgovwww-nsf-gov.jpg)
Figure 4. Computer generated blueprints of Nautilus Minerals' Seafloor Production Tools. http://www.pngindustrynews.net/commonlib/ImageEnlarge.asp?strImageFileName=bulk-cutter.jpg&strImageCaption=A computer model of what the completed bulk cutter will look like. Image courtesy of Nautilus Minerals.
Figure 5. Nautilus Minerals’ Location of Tenements map. http://www.mpi.org.au/wp-content/uploads/2009/08/dyual-island-deep-sea-mining-tenements.jpeg. Mineral Policy Institute.



Deep Sea Mining Campaign: A Project of the Ocean Foundation
Stop Experimental Seabed Mining Petition

News Articles

Aldhous, Peter. "The Deep Sea Gold Rush." New Scientist 29 June 2011: n. pag. Academic Search Premier. Web. 16 June 2014. <http://search.ebscohost.com/login.aspx?direct=true&db=aph&AN=62537931=ehost-live>.
"Deep Sea Mining Licences Issued." BBC News. Ed. David Shukman. BBC, 23 July 2014. Web. 13 Aug. 2014. <http://www.bbc.com/news/science-environment-28442640>.
"Mining the Bottom of the Ocean Is as Bad for the Environment as It Sounds." Motherboard. Motherboard, 7 Aug. 2014. Web. 08 Aug. 2014. <http://motherboard.vice.com/read/mining-the-bottom-of-the-ocean-is-as-bad-for-the-environment-as-it-sounds>.
Thomason, Robert. "CIA Cover Story Gives Birth to Deep Ocean Mining." DC Bureau. Natural Resources News Service, 10 Mar. 2014. Web. 08 Aug. 2014. <http://www.dcbureau.org/201403109664/natural-resources-news-service/cia-cover-story-gives-birth-deep-ocean-mining.html>.

Scientific Journal Articles

Becker, Hermann J., Bernd Grupe, Horst U. Oebius, and F. Liu. "The Behaviour of Deep-sea Sediments under the Impact of Nodule Mining Processes." Pergamon 48 (2001): 3609-627. Print.
Frank, Richard A. "Environmental Aspects of Deepsea Mining." Virginia Journal of International Law 15.4 (1975): 815-26. Print.
Nagender Nath, B., and R. Sharma. "Environmental and Deep-Sea Mining: A Perspective." Marine Georesources and Geotechnology 18 (200): 285-94. Print.
Thiel, Hjalmar, and Gerd Schriever. "Deep-Sea Mining, Environmental Impact of the DISCOL Project." Ambio 19.5 (1990): 245-50. JSTOR. Web. 16 June 2014.