Runit Island

Runit Island is a small islet on Enewetak Atoll in the Marshall Islands notable for the concrete-capped containment structure that holds radioactive debris from U.S. nuclear testing in the mid-20th century. The containment structure, popularly known as the Runit Dome or Cactus Dome, covers a crater into which contaminated soil and fragments were placed and then sealed with a concrete cap.

The dome was constructed as part of a cleanup operation carried out in 1979-1980 to consolidate contamination left by atmospheric and underground tests conducted at Enewetak between the 1940s and 1950s. The site has been the subject of ongoing attention because of the long-lived radioactive material beneath the cap and concerns about erosion, sea-level rise and storm impacts.

Runit Island and the dome are remote and not generally developed for tourism; access is by boat from other parts of Enewetak Atoll and visits are limited by logistics and environmental sensitivity.

The island lies within Enewetak Atoll in the northern Marshall Islands, in a remote part of the central Pacific Ocean; the atoll comprises reef islets surrounding a central lagoon and is sparsely inhabited.

• Cleanup and dome date: The dome was installed in 1979-1980 during a U.S. Army-led cleanup operation that consolidated radioactive debris from nuclear testing onto the island and capped it with concrete.
• Environmental concerns: The site remains an environmental and health concern due to the presence of radioactive materials and the effects of sea-level rise and storm damage on the dome's integrity.

What to See #

• Runit Dome (Cactus Dome): The concrete sealed structure commonly called the Runit Dome or "Cactus Dome," which covers a crater filled with contaminated soil and debris left from nuclear testing cleanup operations.