Enewetak Atoll (or Eniwetok Atoll, sometimes also spelled Eniewetok; , , or , ) is a large coral atoll of 40 islands in the Pacific Ocean and with its 850 people forms a legislative district of the Ralik Chain of the Marshall Islands. Its land area totals less than , is not higher than 5 metres and surrounds a deep central lagoon, in circumference. It is the second-westernmost atoll of the Ralik Chain and is west from Bikini Atoll. The U.S. government referred to the atoll as "Eniwetok" until 1974, when it changed its official spelling to "Enewetak" (along with many other Marshall Islands place names, to more properly reflect their  pronunciation by the Marshall Islanders). In 1977–1980, a concrete dome was built on Runit Island to deposit radioactive soil and debris.