This project will develop the first integrated technology and comprehensive suite of methods for in situ Supercritical CO2-Enhanced Mineral Recovery (scCO2-EMR) and permanent carbon storage via carbonate mineralization of mafic-ultramafic formations. This technology addresses the need for cost-effective transformative technologies to decarbonize the mining industry, address depletion of high value ore grades, minimize hazardous legacy of tailing piles, and ultimately develop a resilient supply chain of domestic energy-relevant minerals. We propose to transform mining of energy relevant minerals (e.g., Ni, Co, Cu, Pt, Mn), with the initial focus on Ni, using a carbon-negative technology that will leverage existing horizontal drilling technologies to deliver proprietary scCO2-based leaching fluids to mixed-grade ultramafic assets. Energy-relevant mineral rich fluids will be brought to the surface for processing and CO2 will be permanently sequestered at depth in the form of carbonate minerals. Our carbon-negative technology will expand the CM supply chain by harnesses low value assets while creating a carbon-negative pathway that reduces energy cost by 63% and mineralizes ~110 kg CO2 per kg of metal extracted.