The U.S. Corps of Engineers approved two major mining projects last week, essentially ending the permitting process and allowing the mines to move to the construction stage. Both projects have been in development for more than 20 years. The Rosemont mine in Sahuarita, Arizona, is a $1.9 billion project. Industrial Info first reported on the project in the site study stage in 1996. The NorthMet polymetallic mine in Hoyt Lakes, Minnesota, is a $1.2 billion project, which was first reported by Industrial Info in 1999. However, don't expect the projects to go to construction immediately as litigation from environmental groups regarding water and land use are expected to further delay the projects.