New Caledonia, a specific full size research laboratory to investigate
lateritic Mining resources exploitation development, governance, impacts
over the last century and to promote a new model for responsible mining
Abstract
New Caledonia owns about 25% of the world’s nickel resources, and
around 9% of the world’s reserves, distributed over 300,000 hectares of
concessions allocated to date (18% of the total surface of the main
island). Supergene weathering of ultramafic rocks have led to the
genesis of lateritic nickel-rich ores of garnierite type
(NiO> 1.5%) and / or iron oxi-hydroxide type (NiO
<1.5%) under tropical lateritic conditions that have
prevailed over 30 millions of years. These conditions have shaped the
landscapes while offering Ni-rich regolith easy to exploit by open pit
mining. Since 1880, nickel has been so far used as an economic driver
and a societal development impetus. Since 1998, three worldwide projects
have been developed, using pyrometallurgy (Ni-Si) and more recently
hydrometallurgy (Ni-Fe) ore processes. However, natural erosion,
anthropogenic disturbances (climate change, fires, urbanization, mining)
can add up to disrupt the whole terrestrial and marine ecosystem
functioning at the regional scale.This critical mined zone is covered by
terrestrial ecosystems of great endemic biodiversity and adjoining a
lagoon that has been listed as a UNESCO World Heritage Site in 2008.
Such ecosystems are a valuable natural resource for the sustainable
future for the next generations. Are mining and preserving ecosystems
compatible, and for what economic and societal model? The conference
reviews a collective research approach (mining, terrestrial and marine
ecosystems impacts, restoration, biorecycling) to address this question.
The corpus of acquired knowledge allows to propose an inclusive model of
responsible mining activity, based on the “co-valorization” of both
non-renewable and renewable primary resources through the development of
circular economy and bio-economy principles, and applied all along the
“mining ecosystem” project management. Considering i)the present day
low GDP input of nickel mining in New Caledonia, the 98% dependency
rate from fossil sources of energy, the CO2 emissions and the volatile
Ni-market international context, this model, if followed, will reinforce
the societal cohesion and develop a sustainable economy diversification,
while enhancing energy transition and a better ecological efficiency.