The Pacific paradise of Enewtak Atoll harbours a devastating secret - the toxic legacy of American nuclear testing. Between 1946 and 1958, the US military tested 43 nuclear bombs in the Pacific. Now a concrete dome - 46cm thick - seals 80,000 cubic meters of radioactive waste on the deserted island of Runit. But the dome is not working. Rising sea levels threaten to flush a vast stash of highly radioactive plutonium into the Pacific Ocean. This is not the only fallout - the soldiers who cleaned up the mess and the Marshallese islanders are abandoned by a government refusing any responsibility.