wa os northern atoll reef. The island chain is quite long and narrow and has only sparse vegetation. Several ‘tests of nuclear devices were conducted in the near vicinity of this island complex, and thus the extremes in radiation leveis typical of blast areas were found here. A survey using the portable meters was made along a route down the middle of the complex. These measurements ranged from 5 to 20 ur/hr on Aomen, 20 to 330 ur/hr on Lomilik, to 40 ur/hr on troij, and 3 to 7 ur/hr on the causeways. 10 Except for the higher values on Lomilik, these exposure rates were typical of weathered, sandy soils capable of only low retention of radioactive materials. The hot spots on mney Lomilik were depressed areas with clay-like soil. A soil sample was taken from the area of greatest activity. The soil analysis indicated that ®°Cco was responsible for more than 3/4 of the total exposure rate, with *85ch and lesser amounts of ~°?™ph and *°’¢cs contributing almost all the remainder. 155 Traces of 1°° Rh, *°.Rh, 14446, Eu, and ***Am, and thus *°°Pu were also detected (see Figure 12). A 1964 sample from Iroij indicated that at that time ©°Cco contributed about 75% of the total exposure rate, 122 sb about 8%, *87 63 about 9%, and +°2Mph the remainder, in substantial agreement with the 1967 data for Lomilik. Many pieces of fairly radicactive metal scrap were found throughout this area. Although most of the time this contamination was due to °°Cc several samples exhibited only unidentified 240 keV gamma-ray activity.