BHP and Rio Tinto (in a joint venture called Resolution Copper) sought for years to access the underground copper deposit in the Tonto National Forest, next to the San Carlos Apache reservation. The San Carlos Apache and other tribes have always been opposed to mining at Oak Flat, Arizona, a sacred site used for religious ceremonies. However there are no federal laws giving Native Americans control of ancestral lands that are outside reservation boundaries. The tribes were blindsided in 2014 when a proposal to exchange federally owned Oak Flat for private land owned by Resolution Copper was included, at the last minute, in a defence spending bill at the behest of four Arizona members of Congress who supported Resolution’s mining plans; the bill was signed into law by the president, Barack Obama with the caveat that the swap could not occur until an environmental study was published which was due to be in 2021 (see 2020 below).