Runit Dome
© U.S. DEPARTMENT OF ENERGY (PUBLIC DOMAIN)Aerial photo of the Runit Dome.
The tropical blue skies over the southern Pacific Ocean were enveloped by towering mushroom clouds lingering over the Marshall Islands in 1954 as the United States continued its testing of nuclear weapons.

The United States conducted 67 nuclear weapon tests from 1946 to 1958 on the pristine Marshall Islands. The most powerful test was the "Bravo" hydrogen bomb in 1954, which was about 1,000 times more powerful than the bomb dropped on Hiroshima, Japan.

The extensive nuclear bomb testing blanketed the islands in radioactive ash, covering it in the fine, white, powder-like substance. Children, unaware of what the radioactive ash was, played in the "snow" and ate it according to the Atomic Heritage Foundation.

Today, there are growing concerns that the temporary containment of the nuclear waste resulting from those tests is leaking into the Pacific Ocean and could be cracked wide open from the next storm that rolls by. Specifically, the site is believed to be leaking one of the most toxic substances in the world, the radioactive isotope plutonium-239, a byproduct of nuclear bombs that decays with a half-life of 24,100 years.

Runit Dome from above.
© U.S. DEPARTMENT OF ENERGY (PUBLIC DOMAIN)Runit Dome from above.
In 1977 the United States worked to clean up the radioactive waste left strewn across the Marshall Islands. In total, an estimated 73,000 cubic meters of radioactive soil was collected across the Marshall Islands. The US used a crater from an especially large nuclear bomb test on Runit Island to stash away the radioactive soil. The 328-foot crater from a May 1958 test was designated the dumping ground.

As this was considered a temporary solution, the crater bottom was not lined with impervious material, which would have prevented radioactive waste from entering the below aquifers and Pacific Ocean. After the material was piled into the crater, an 18-inch thick concrete dome was positioned on top of it as a temporary containment. Plans for permanent radioactive waste storage were never finalized and thus the temporary solution has sat as-is for nearly 40 years.

Shortly afterward, in 1983 the Marshall Islands agreed on their severity from the United States and with it, the islands released the United States of any responsibility for past nuclear testing.
Bikini Atoll, Micronesia
© GettyJuly 25, 1946 - A nuclear weapon test by the American military at Bikini Atoll, Micronesia. The explosion was part of Operation Crossroads.
Rising sea level, soil shifting, and storms have all caused new concern over the integrity of the "nuclear coffin" and its ability to contain radioactive waste. The dome is reportedly cracking and the local government fears the next big storm may split the concrete dome apart. In addition, groundwater models suggest that seawater is almost certainly accessing the crater. However, it is unclear how much nuclear waste is seeping from the unlined crater bottom into the Pacific Ocean and groundwater aquifers.

Despite recent awareness around the issue, the Marshallese government does not have the money or expertise to properly clean up and isolate the nuclear waste. Thus, the Marshallese are left helpless as their tropical islands continue to leak deadly radioactive waste across its coral reefs.