The organization's report noted that "The Amad Plan was downsized in late 2003 before this plant processed any weapon-grade uranium, although it did process a considerable amount of a non-uranium surrogate material into weapon components. The use of a surrogate material allowed Iran’s nuclear weapons program to learn and practice the fabrication of key nuclear weapon components."The scientists wrote, "The key building of the site, the uranium metals workshop, was apparently gutted and abandoned between late 2010 and early 2011."