Boerne See oe, PREFACE Betw-en 1948 and 1958 Enewetak Atoll in the Marshall Islands for U.S. nuclear weapons testing and 43 devices were exploded In 1972 the federal government announced that it would rehabil atoll and return it to the government of the Trust Territory o Pacific Islands and, subsequently, to the Enewetak people, who moved to Ujeling in 1947, 125 miles southwest of Enewetak. The Enewetak rehabilitation effort involved many departmen federal governmant with the Defense Nuclear Agency (DNA) being with the major radiological cleanup responsibility. In the pr this cleanup, radiologically contaminated soil and debris fr the islands in the atoll were collected and transported to on the eastern side of the atoll. ‘The contaminated material contained in a soil-cement matrix in Cactus Crater, which had formed by one of the nuclear detonations. This material was by a concrete key-wall and covered by a concrete cap. In ecrder to provide the people of Enewetak and the Marsha government with an objective assessment of the safety of this ment structure, the DNA requested the National Academy of Sciehces, through the Advisory Board on the Built Environment” (ABBE) o National Research Council, to “assess the effectiveness of th Crater structure in preventing harmful amounts of radioactivi becoming available for internal or extern..4 human exposure"; added later that this assessment should bt "set against an un standing of the expected living patterns + f& the people of En terms of their degree of cont#.:% with Rurit Island and their otherwise to residual radioactivity en the atrll." The committee appointed tc conduct the study concentrated on two issues: (1) the potential hazard of trarnsuranics bein ported to the surrounding enviroment from the structure in i configuration, and (2) possible sequences of events that coul the structure's physical integrity and an estimation of radio. hazards that might result from the dome's breachment. Two su issues also concerned the committee and are commented on in t namely, possible hazards associated with the quarantined isla *Formerly the Building Research Advisory Board ° vill (BRAS). present affect tive idiary report; of