>$1 billion spent. No reserves. “The 2021 PEA is preliminary in nature, and includes Inferred mineral resources that are considered too speculative geologically to have economic considerations applied to them that would enable them to be categorized as mineral reserves. There is no assurance that the 2021 PEA will be realized. Mineral Resources that are not mineral reserves do not have demonstrated economic viability, and there is no assurance that the Pebble Project mineral resources will ever be upgraded to reserves.”
https://www.sec.gov/Archives/edgar/data/1164771/000106299322013102/exhibit99-2.htm
A “preliminary economic assessment” or “PEA” is typically the first stage of economic analysis and the accuracy level is the lowest.