A Ticking Time Bomb: The Concrete Dome of Runit Island

AT Hall
March 10, 2018

Submitted as coursework for PH241, Stanford University, Winter 2018


Fig. 1: The Runit Dome on the Enewetak Atoll. (Source: Wikimedia Commons)

The Marshall Islands are located in the Pacific Ocean. They lie right between Hawaii and Australia with absolutely no major land masses around. This stretch of islands seem to be peaceful, thriving, and clean if looked at from afar. But as you pass over, there is one island with an interesting structure built on it. It looks almost like a UFO that crashed from space, but it is actually just a giant concrete dome. This dome can be found on Runit Island on the Enewetak Atoll. This stretch of islands is one of the most radiated pieces of land in the world.

Nuclear Testing in on the Bikini and Enewetak Atolls

During the period between 1948 and 1958, the United Stated conducted all sorts of nuclear tests in the northern parts of the Marshall Islands. Two groups of islands, in particular, were the targets: the Bikini and Enewetak Atolls. The ten-year period in which this testing took place absolutely devastated all forms of life on these stretches of islands. In the Enewetak Atoll, there were 42 atmospheric nuclear weapons tests that took place in the near-surface environments of the atoll. [1] The Bikini Atoll took less of a hit; it had 14 tests run in that time. [1] Runit island alone experienced eight round surface tests, eight barge tests conducted from anchor points in the nearby lagoon and on the ocean reef, and one targeted airdrop. [1] These two Atolls alone during 1948 to 1958 accounted for more than 50% of the global fallout from 66 different nuclear tests. [2]

Runit Island

The Runit Island dome symbolizes all of the testing done in this area. It is an attempt to save the environment by putting away hazardous nuclear material. Unfortunately, it is actually making the situation worse. In 1958, Runit Island was the sight of a "Quince" nuclear test and in 1979 when the United Stated went to clean up after the testing approximately "266 GBq of TRU activity (Pu-238 + Pu-239 + Pu-240 + Am-241 = TRU) contained in 8,200 m3 of soil was recovered from the...Quince zone." [1] The island was eventually deemed uninhabitable. In 1979 the United States sent out a cleanup crew to contain the radioactive material. [1] A concrete dome inches thick was constructed constructed to house 111,000 cubic yards of radioactive material that accumulated through 12 years of tests (Fig. 1). [3] One of the major problems of the construction was that the bottom was not sealed with concrete. As a result, radioactive waste is slowly and continuously leaking into the ocean.


The United States devastated this pocket of islands with no regard to its ecosystem. It contaminated the waters and the land to the point that people can no longer live there safely. Runit Islands dome was an attempt at cleaning up the mess. Unfortunately, it is still hurting the environment. Today, there are other concerns with the dome. Sea levels are rising, and if the dome gets covered, all of the nuclear waste will be exposed to the ocean. If this happens, who knows how far the effects will be felt. Something needs to be done in regards to the safety of this dome.

© AT Hall. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.


[1] K. O. Buesseler et al., "Lingering Radioactivity at the Bikini and Enewetak Atolls," Sci. Total Environ. 621, 1185 (2018).

[2] C. Jose, K. Wall, and J. Hendrik, "This Dome in Pacific Houses Tons of Nuclear Waste and It's Leaking," The Guardian, 3 Jul 15.

[3] T. F. Hamilton et al., "Frequency Distribution, Isotopic Composition and Physical Characterization of Plutonium-Bearing Particles From the Fig-Quince Zone on Runit Island, Enewetak Atoll," J. Radioan. Nucl. Chem. 282, 1019 (2009).