| New-Caledonia being the 6th nickel world producer, mining deeply integrates into local history, economy and culture. Regular prospecting covers the increasing need in mineral resources. However, New-Caledonia alsoharbors a very sensible environment with a75% rate of endemism in biodiversity. Mining activities already severelydegraded landscapes, and environmental regulations are becoming more stringent. To limit the impact on natural milieus while accessing virgin areas, mining companies elected helicopter-borne drilling as a strategic prospecting method. For each geological target, a sub-horizontal platform is realized withland clearing and excavation / backfill earthworkon a surface below 50 m2, using helicopter-lifted equipment. Afterwards,topsoil and brushes are leveled back asa compulsory remediation.Nonethelessplatforms still affects the area, mostly through stability,erosion and revegetation issues.This thesis manuscript is dedicated to improving environmental reliability of practices in platform realization. Initially based on assessingthe procedures from 2010 and observing current practiceson sites, the study reveals that incompliances hinder platforms' environmental quality. As a first solution, correcting measures are applied,implementing supervision of operators and validation stages. Then, to set up further ameliorations,trials are designed focusing on support structures and remediation, to select amendments for their efficiency, quickness in application and few additional costs. Through analysis of these experiments, procedural update can be achieved with both adjustmentsto adapt theory to practical feasibility and innovative measures aiming at more environmentally-friendly outcomes.Provided that procedures are being complied to, short term accomplishments demand simple adaptations and innovative addendums. However, improving is a never ending commitment and new ideas are already emerging to pursue practices betterment. |
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