As cleanup efforts continue in Washington state at a decommissioned U.S. nuclear facility that played a crucial role in the country's acquisition of the atom bomb in World War II, questions linger over whether the site has caused serious health issues for workers and local residents.

Construction began on the facility, known as the Hanford site, eighty years ago, in 1943, and involved the building of the world's first large-scale nuclear reactor.

Through the Manhattan Project, a U.S. government research and development program for building nuclear weapons, the site's B reactor, erected on a 580-square-mile stretch of land next to the Columbia River in south-central Washington, produced the nuclear material for one of the only two atomic bombs ever used in an armed conflict.