New Caledonia, a Pacific archipelago, is a biodiversity “hotspot” with exceptionally high numbers of endemic species that are severely threatened, especially by mining activity. Administered by France since 1853, New Caledonia has a population of approximately 269,000, comprised of several ethnic groups, primarily Melanesians known as Kanak (40 percent), and people of European ancestry (29 percent). Mined since 1874, New Caledonia currently hosts over 30 active mine sites, some run by locally-based entrepreneurs and others by multinational corporations. Grande Terre, the main island, is estimated to possess nearly 25 percent of the world’s nickel reserves and is the second largest producer of ferronickel and fifth greatest source of nickel ore. Vale’s “Southern Refinery” project, at first named Goro Nickel and now officially called Vale Nouvelle-Calédonie, is located at the southern tip of the main island of New Caledonia. It involves mining nickel and cobalt, as well as construction of a refinery that uses hydrometallurgical technology. In this procedure, never before implemented in New Caledonia, acid under pressure leaches nickel and cobalt from the ore, with effluent discharged into the sea. Vale completed a pilot refinery in 1999 and the commercial refinery in 2008. Operations are continuing, despite delays caused by acid leaks in 2009, 2010, 2012, and 2014 (both the first and most recent of which devastated the local freshwater ecosystem), and the effluent diffuser’s rupture in 2013. Rhéébù Nùù, a group led entirely by Kanak, was formed in 2002 to focus on the Southern Refinery. While not entirely opposed to the mining project, these protestors had concerns about its potential environmental impacts, particularly on the marine resources upon which the local population depends for subsistence and livelihood. Rhéébù Nùù, and the villagers they represented, were especially concerned about what was popularly known as “the pipe”, the diffuser that would transport waste products, including neutralized sulfuric acid and dissolved metals, into the Havannah Canal, where local people fish. The most dangerous impact has been almost entirely ignored: mercury from the coal-fired power plant, which will contaminate local seafood, upon which the communities depend for sustenance. They were also concerned that Kanak would not benefit adequately from employment with the project, as evidenced by the company importing Filipino workers for the construction phase. Believing that local residents needed to keep an “eye” on the project, they named the group Rhéébù Nùù, “eye of the country” in the indigenous language Numèè. For six years, Rhéébù Nùù leaders initiated a series of actions including pamphlets denouncing the company’s activities, public meetings at local villages, open letters sent to political leaders, legal action in the courts, and blockades of the construction site which turned into violent encounters with armed police. In early 2008, Vale began laying the submarine pipeline for its effluent diffuser, sparking fresh protests and blockades, especially at nearby Ouen Island. However, in September 2008, four Rhéébù Nùù leaders, twenty-five customary authorities and two Goro Nickel representatives signed a “Pact for Sustainable Development of the Far South [of New Caledonia]”. Through this agreement, the mining company committed to creating both a Corporate Foundation to fund local development initiatives and a “Consultative Customary Environmental Committee” composed of senior male customary authorities who could recommend further studies, to recruiting and training ten local youth as “environmental technicians”, and to an extensive reforestation program. In exchange, Rhéébù Nùù members committed to “assert their point of view not through violent or illegal actions, but by dialogue”.
UPDATE Feb 2019: Vale confirmed a massive investment of 500 millions of dollars  for the period 2019-2022, to meet the increasing demand of nickel and cobalt by the electric automobile industry. In a citation reported in the newspaper ""Il s'agit d'un signe de confiance dans la transformation du marché. Jusqu'alors, on exportait pour les aciéries mais nous sommes en train de changer complètement de pied, vers des segments de marché qui demandent un nickel premium, notamment pour les batteries des voitures électriques", stated Antonin Beurrier, CEO of Vale-NC .
Production is aimed to increase from 35,000 to 50,000 tonnes of nickel within ten years. Cobalt extraction is projected to amount to 2,000 tonnes in 2019 .
Yet, increased concern in Nouvelle Caledonie for dam safety after the tragedy in Brumadinho (Brazil, 25th Jan 2019), urged all dams in the country to be put in greater safety. It also urged Vale to scrap a waste park project called PGA Prony Pernod (which would included a 4 km long and 80 m high dam. Vale Nouvelle-Calédonie then announced a new project, "Lucy", for storing dried waste .