Why were Bikini islanders evacuated again after attempting to return in the 1970s?

Bikini islanders who attempted to return to their homeland in the 1970s were evacuated again in 1978 because it became clear that the atoll remained dangerously contaminated with radiation from the United States nuclear testing program conducted between 1946 and 1958.12

Although the U.S. government initiated a long-range project in 1969 to reclaim the land and facilitate repatriation, the trial resettlement revealed that the environment was not safe for permanent habitation. Scientific assessments determined that radioactivity levels on the atoll were still too high, making it impossible for the islanders to safely consume food grown on the land or reside there permanently. Consequently, the inhabitants were moved back to Kili island. Subsequent cleanup efforts have since deemed the radiation levels low enough to permit limited activities like tourism and scuba diving, but the land remains unsafe for resettlement.123