- RADIOLOGICAL CLEANUP OF ENEWETAK ATOLL Description and History: 1526-1972 31 When that war was concluded, Japan, having been on the side of the victorious Allies, was awarded the islands lying north of the equator by the Treaty of Versailles. This was in the form of a mandate to control and develop these islands, but not to fortify them. owe eee - 30 The Japanese established the South Seas Bureau with headquarters at Kolonia in Ponape, and divided the mandated territory into six districts, one of which was the Marshall Islands. Visits to Enewetak were made by the Japanese Navy and by Japanese traders. Both Enewetak and -Ujelang were administered from Ponape, and the only foreign residents on Enewetak were a Japanesetrader and his two assistants. A weather station wasestablished there in the 1930’s, but other Japanese associations with after.43 the atoll languished. defense on the atoll. These were placed on Enjebi, Medren, and Enewetak. About 1,000 laborers and other noncombatant personnel were also present. The aviation personne! were to be evacuated to Truk by flying boat but, for most of them, this operation was begun too late.42 Noting the preparations for battle, the 30 dri-Enewetak inhabitants of Enjebi moved to islands on the eastern reef. BATTLE OF ENEWETAK: FEBRUARY 1944 The original U.S plan for invading the Marshalls included amphibious assaults on strongly defended atolls of the Ratak or eastern chain in order to secure airstrips there. Air reconnaissance in December 1943 showed the construction of a Japanese airstrip on Kwajalein Island, so plans were altered to bypass Wotje, Maloelap, and Mili on the Ratak Atolls, and to attack the north and south ends of Kwajalein Atoll! simultaneously. Planning included the capture of Majuro Atoll which was very lightly The Marshall Islands operation was code-named ‘‘Flintlock’’ and was. under the overall command of Vice Admiral Raymond.A. Spruance. The capture of Enewetak was considered to be a preliminary step to landing on Truk farther west and was code-named ‘‘Catchpole.’’ Many ofthe lessons learned in the previously completed campaign to capture the Gilbert eee construct an airstrip. This was completed in July 1943, and, in October, the detachment at Kwajalein was moved to Enjebi to act as a maintenance force. In January 1944, II0 aviation officers and men were billeted on Enjebi, and 2,686 soldiers were landed on Enewetak to prepare the ~ Enjebi until December 1942, when construction workers arrived to we. Early in World WarII, the Japanese set out, contrary to the termsof the mandate, to make Enewetak Atoll a strategic base in their planned conquestof the Pacific. Japan maintained a guard unit of about 20 men on Islands were employed in the assault on Kwajalein. This included heavy naval bombardment by battleships, use of infantry landing craft to saturate the landing beaches with high explosive fire, use of tracked landing vehicles to transport assault infantry across the coral reefs to dry beaches, and establishment of field artillery on lightly held islands adjacent to the objective islands to provide close-in artillery support for the main assault groups. The result at Kwajalein Atoll was the capture of Roi-Namur in the north and Kwajalein Island in the south, with the loss of 372 killed and 1,582 wounded. The enemy strength was estimated to be 8,675, of which only 265 remained alive to be taken prisoner and, of these, 165 were Korean laborers. The seizure of Enewetak Atoll was to follow immediately The Enewetak Expeditionary Group was commanded by Rear Admiral Harry W. Hill. The assault troops were under Brigadier General ThomasE. Watson. The plan was to complete the occupation in four phases. Phase One was the seizure of twoislets south of Enjebi— Aej (Olive), and Lujor (Pearl)—where field artillery would be emplaced. Phase Two was the landing on Enjebi by Marines, supported by the emplacedfield artillery. Phase Three was to be the seizure of Enewetak Island and Medren. Phase Four was a mopping-up operation of the remaining islands to rid them of any remaining Japanese.44 The map in Figure 1-3l shows the location of these events. At 0700 hours on 17 February 1944, minesweeping began and was followed by the entry of troop transports into the lagoon. Phase One was completed by 1632 hours with the positioning of Marine and Army artillery on Aej and Lujor. Marine scout company landings on Enjebi took place at 0315 hours on 18 February, and the island was secured by 1600 hours. The third phase, the capture of Enewetak and Medren Islands, began on the morning of 19 February with the 106th Infantry landing on Enewetak Island. The island was not pronouncedsecure until! 1630 hours on the 2st. In the meantime, Marine artillery had landed on Japtan, and guns emplaced there and on Enewetak were registered on Medren by 1200 hours on 20 February. Marines landed on Medren at 1900 hours on the 22nd, and Phase Three was completed by 1930 hours of the same day.45 Figures 1-32 and 1-33 show some of the action during the battle. In conducting Phase Four, no opposition was met in landing and occupying the other islands of the atoll. All action had ceased by the evening of 32 E i jttenlens Only 64 Japanese were taken prisoner, some of whom were wounded. Most had died fighting.4® Fifty dri-Enewetak were found on D+1 by American troops and were sheltered in a huge bomb crater. Other people found later in the battle were brought there also, including 17 from Medren. On 24 February 1944, all of the surviving people were moved to