Nickel mining in New Caledonia
Encyclopedia
Nickel mining in New Caledonia is a major sector of the New Caledonia
New Caledonia
New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

n economy. The islands contain about 7,100,000 tonnes of nickel
Nickel
Nickel is a chemical element with the chemical symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile...

 which is about 10% of the world's nickel reserves. With the annual production of about 107,000 tonnes in 2009, New Caledonia was the world's fifth largest producer after Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

 (266,000), Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...

 (189,000), Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 (181,000) and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 (167,000). Nickel production in New Caledonia accounts for 7–10% the country’s GDP
Gross domestic product
Gross domestic product refers to the market value of all final goods and services produced within a country in a given period. GDP per capita is often considered an indicator of a country's standard of living....

 and is responsible for as much as 80% towards foreign earnings. With the exclusion of tourism, nickel ore and derived metallurgical products represent about 97% of the total value of exports.

History

New Caledonia has the longest history of mining in the Pacific islands. Nickel was found in New Caledonia in 1864 by the engineer Jules Garnier. It was distributed in the ore layers which cover about one third of the area of the main island of New Caledonia. The nickel concentration was inhomogeneous and also varied with the depth. Whereas its usual concentration was 2–5%, it could reach 10–15% in scattered deposits of green garnierite
Garnierite
Garnierite is a general name for a green nickel ore which is found in pockets and veins within weathered and serpentinized ultramafic rocks. It forms by lateritic weathering of ultramafic rocks and occurs in many nickel laterite deposits in the world. It is an important nickel ore, having a large...

. Those areas were developed first using primitive manual extraction methods and were gradually depleted, resulting in the present average concentration of about 2.6%. This nickel is located at the depth of about 30 metres (98.4 ft). Shallower layers of 10–20 m (32.8–65.6 ft) also contain nickel, but at twice smaller concentration. They remain unexploited and constitute most of the nickel reserves of New Caledonia.

Wide-scale mining started in 1875 in Houaïlou
Houaïlou
Houaïlou is a commune in the North Province of New Caledonia, an overseas territory of France in the Pacific Ocean....

 and Canala
Canala
Canala is a commune in the North Province of New Caledonia, an overseas territory of France in the Pacific Ocean.-History:On 25 April 1995 about 47% of the territory of Canala was detached and became the commune of Kouaoua....

 communes. Early mining was done by hand and then gradually became mechanised. By beginning of the 20th century two large mines at Bourai and Thio were established. In the initial years, after nickel was discovered mining was done in about 330 mines. However in 1981 there were only 30 functional mines as against 130 in the early 1970s.

Because of the remote location of the islands, about half of the ore was smelted
Smelting
Smelting is a form of extractive metallurgy; its main use is to produce a metal from its ore. This includes iron extraction from iron ore, and copper extraction and other base metals from their ores...

 locally, despite the underdeveloped industrial infrastructure of New Caledonia. Another half was exported, mainly to Japan. The first nickel smelter was built in 1879 with two other added in 1910 and 1913. The smelted product contained about 70–80% nickel and was sent for refining to France. Because of low nickel content in the ore, local smelting resulted in vast amount of displaced rocks near the smelters that changed the local landscape.

The production of ore was nearly constant between 1875 and 1948, but then increased about 70 times reaching a peak of about 8 million tonnes in 1971. This rise followed by a decline, to about 4 million tonnes of ore in 1981, due to cyclones, reducing demand for the metal and increasing role of other world producers, such as Indonesia, Philippines and Australia. Correspondingly, the mined area decreased from 21500–8700 ha (53,127.6–21,498.1 acre) and the number of people employed in the industry from about 6,200 to about 3,600. Nearly half of them worked at the mines and another half at the major Doniambo processing plant near Noumea
Nouméa
Nouméa is the capital city of the French territory of New Caledonia. It is situated on a peninsula in the south of New Caledonia's main island, Grande Terre, and is home to the majority of the island's European, Polynesian , Indonesian, and Vietnamese populations, as well as many Melanesians,...

.

Mines

Strip mining is the most common technique adopted for nickel mining and statistics show that stripping of 500 million tonnes of overburden had to be removed to extract nickel ore, which amounted to clearing an area of 20 hectares (49.4 acre) per million tonne (five million tonnes of ore per year generate 25 million tonnes of tailings).

The local nickel industry is dominated by the French company Eramet
Eramet
Eramet is a French multinational mining and metallurgy company, listed on the Euronext Paris exchange under the symbol ERA.The company produces non-ferrous metals and derivatives, nickel alloys and superalloys, and high-performance special steels....

 which has a 60% interest in its nickel mining subsidiary, SLN (Societe Le Nickel) in New Caledonia. Other firms such as Falconbridge Ltd.
Falconbridge Ltd.
Falconbridge Limited was a Toronto, Ontario-based natural resources company with operations in 18 countries, involved in the exploration, mining, processing, and marketing of metal and mineral products, including nickel, copper, cobalt, and platinum. It was listed on the TSX and NYSE , and had...

, Inco
Inco
Vale Canada Limited is a wholly owned subsidiary of the Brazilian mining company Vale. It is Vale's nickel mining and metals division and is headquartered in Toronto, Ontario, Canada...

, Argosy Minerals and QNI however are still active in New Caledonia, particularly Inco in the Goro mine which produces both nickel and cobalt
Cobalt
Cobalt is a chemical element with symbol Co and atomic number 27. It is found naturally only in chemically combined form. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal....

, about 54,000 tonnes of nickel annually.

Despite a decline in the nickel mining, New Caledonia remains one of world's largest producers of laterite
Laterite
Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...

, a source of ferronickel
Ferroalloy
Ferroalloy refers to various alloys of iron with a high proportion of one or more other element, manganese or silicon for example. It is used in the production of steels and alloys as a raw material.The main ferroalloys are:*FeAl – ferroaluminum...

 (an alloy of iron and nickel) which constitutes about 20% of country's production. Another 80% is nickel extracted from saprolite
Saprolite
Saprolite is a chemically weathered rock. Saprolites form in the lower zones of soil profiles and represent deep weathering of the bedrock surface. In most outcrops its color comes from ferric compounds...

. In 2008, New Caledonian ferro-nickel was mostly exported to the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 (41.8%), Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 (18.2%), Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...

 (18.2%), China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 (8.0%), India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, South Korea
South Korea
The Republic of Korea , , is a sovereign state in East Asia, located on the southern portion of the Korean Peninsula. It is neighbored by the People's Republic of China to the west, Japan to the east, North Korea to the north, and the East China Sea and Republic of China to the south...

 (2.4%) and the United States. On the contrary, all smelted nickel is sent to France.

The major mines are Goro
Goro, New Caledonia
Goro is a major mining settlement in South Province, New Caledonia. The Goro mine is one of the world's biggest nickel mines....

, Thio
Thio, New Caledonia
Thio is a commune in the South Province of New Caledonia, an overseas territory of France in the Pacific Ocean.A novel Aerial tramway existed here at the start of the 20th century to facilitate loading ore ships offshore...

, Koniambo, Kouaoua
Kouaoua
Kouaoua is a commune in the North Province of New Caledonia, an overseas territory of France in the Pacific Ocean. Nickel mining is operated in Kouaoua.-History:...

, Nepoui – Kopeto and Etoile du Nord. Recently the new Tiebaghi
Tiebaghi
Tiebaghi is a mine and former village in Kaala-Gomen, New Caledonia. Located on an ultramafic massif, it was the largest chromium mine in the world in 1941, producing about 54,000 tons per year. During World War II it produced about 4400 tons of nickel per year. The mine is currently extensively...

 mine has been opened which will be responsible for some 30% of SLN’s annual production, accounting to 20,000 tonnes per year.

Goro Nickel Plant

Goro Nickel Plant
Goro, New Caledonia
Goro is a major mining settlement in South Province, New Caledonia. The Goro mine is one of the world's biggest nickel mines....

, is one of the largest under construction, estimated to cost $3.2bn, with planned capacity of 60,000 tonnes of nickel per year from laterite
Laterite
Laterites are soil types rich in iron and aluminium, formed in hot and wet tropical areas. Nearly all laterites are rusty-red because of iron oxides. They develop by intensive and long-lasting weathering of the underlying parent rock...

 with proven reserves of 120 million tonnes. In addition, cobalt will also be mined here from saprolite
Saprolite
Saprolite is a chemically weathered rock. Saprolites form in the lower zones of soil profiles and represent deep weathering of the bedrock surface. In most outcrops its color comes from ferric compounds...

 deposits. The proposed method is opencast extraction from the depths of 50–60 m (the shallower layers have no commecial value). The major share in the Plant is held by a consortium with Vale Inco (of Brazil) holding a 69% hare and a joint company called Sumic Nickel Netherlands, Japan's Sumitomo Metal Mining Co. Ltd., and Mitsui Co. Ltd., holding 21%.share. The three provinces of New Caledonia hold the balance 10 % share. The project was stalled for a while as the local community of Kanak people stiffly opposed the project, particularly of laying the offshore line. The plant is yet to be commissioned.

Environmental impact due to Nickel mining

Even though the nickel mining operation is crucial to the economy of the region, its environmental adverse impacts on the environment and ecology have invited protests from the Environmental lobbies. The environmental groups, with its social and political undertones are seeking remedial measures to redress mines' landscape impacts and the ecological aspects. Some of the impacts brought out are the following.

Ramsar Organization
Ramsar Convention
The Ramsar Convention is an international treaty for the conservation and sustainable utilization of wetlands, i.e., to stem the progressive encroachment on and loss of wetlands now and in the future, recognizing the fundamental ecological functions of wetlands and their economic, cultural,...

 dealing with wetlands has brought out a few adverse effects from the nickel mining operations on the wetlands in the interior regions of New Caledonia. Many wetlands have either been lost or spoiled. Rivers and streams have been choked with tailings from the waste material dumped from the nickel mines. This has resulted in rise in bed levels of the rivers and consequent flooding affecting fertile agricultural lands. Many river delta areas have been affected creating changes in aquatic flora and fauna; the mining effluents are reported to have affected about 40 streams in their middle and lower reaches. Even estuaries and bays are reportedly affected by the “red clay and lateritic sub-soil,” which covers some of the mangrove forests.

During the boom period of nickel extraction in the state, there were serious visible effects on the environment, consequent to stripping of hill slopes. Erosion of hill slopes are reported to have continued, even after closure of some open cut mines in the Theo Mining Centre on the east coast of the main island. It is reported that the Thio centre provides, especially its Plateau mine (Theo Mining centre once produced 20 million tones of nickel ore), the most striking example of the environmental damage caused by mining activity in New Caledonia. A study carried out in 1991 had observed that 1 million tonnes of solid mass of dumped material from the nickel mines caused shift of the delta of a lagoon by about 300 m due to sedimentation. However, it is also observed that nickel mining is a "politically sensitive subject...it remains the most important economic sector on the island”. Studies done at Noumea (the capital of the Island) had established that the flumes from nickel factories jetted out a plume of black and red smoke. The discharges from the factories had also recorded high levels of nickel, arsenic and lead, apart from phenol
Phenol
Phenol, also known as carbolic acid, phenic acid, is an organic compound with the chemical formula C6H5OH. It is a white crystalline solid. The molecule consists of a phenyl , bonded to a hydroxyl group. It is produced on a large scale as a precursor to many materials and useful compounds...

, hydrocarbon
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons from which one hydrogen atom has been removed are functional groups, called hydrocarbyls....

s, hydrogen sulfide
Hydrogen sulfide
Hydrogen sulfide is the chemical compound with the formula . It is a colorless, very poisonous, flammable gas with the characteristic foul odor of expired eggs perceptible at concentrations as low as 0.00047 parts per million...

, PCB and pyraline. The head of the bay area also recorded higher levels of nitrites, nitrates and phosphates.

Mines now in operation are better managed under opencast mining as compared to the past. However, according to environmental impact studies carried out, two new large nickel mining and processing plants have been identified as detrimental to the adjoining coral reefs and also to plant and animal species. Planned mitigation measures may still eliminate some adapted species.

Pollution abatement measures

The government of New Caledonia has evolved strategies, technologies and policies to maintain the balance between environmental conservation measures and mining industry. The new legislation has ensured enforcement of installing pollution abatement equipment followed by re-plantation of vegetation after mine is exploited, and technological improvements for efficient economic extraction concomitant with environmental friendly pollution control measures. The government regulations have been effectively adopted by mine inspectors and through environmental impact assessments since 1992, even though regulations have been existence for 15 years prior to that. Apart from introducing new techniques, other measures adopted for environmental abatement are: 14 zones covering 19430 hectares (48,012.5 acre) have been declared protected areas from prospecting or mining, construction of sedimentation barriers, catchment area treatment, creation of settlement basin and terraces to reduce silt flow into streams and rivers, minimum road building activity in the area of mining, creation of a vegetation barrier along roads and in the vicinity of the mines, adopt satellite remote sensing techniques for mapping and locating mining areas which would avoid road building for the purpose and completely re-vegetate the closed or fully extracted mines. In addition, a monitoring team of inspectors of mines is also instituted to check and ensure that pollution abatement measures are fully implemented. In 1994, a mining centre was set up at Nepoui-Kopeto not only to increase productivity levels by adopting modern mining methods but also to develop pollution control capabilities at mining sites.
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