hamber ions 1 ed on iformity ar both ap were measureon the iks of for a with the have mate. ite e area arious osure y NaI(T1) ibute st all Figure ¥ is S415. 2ntical sible -e that j May 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 levels 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, 10 to 40 wr/hr on Troij, and 3 to 7 ur/hr on the causeways. 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 Lomilik were depressed areas with clay-like soil. A soil sample was taken from the area of greatest activity. The soil analysis indicated that e°Co was responsible for more than 3/4 of the total exposure rate, with *#°Sb and lesser amounts of ~°*™Rh and *7’cs contributing almost all the remainder. MTraces of 1°" Rh, +°1Rh, 144% Ge, *5° Bu, and 247 Am, and thus ***pu were also detected (see Figure 12). A 1964 sample from Iroij indicated that at that time *°Co contributed about 75% of the total exposure rate, **8sh about 8%, *°’Ccs about 9%, and *°®™ph the remainder, in substantial agreement with the 1967 data for Lomilik. Many pieces of fairly radioactive metal scrap were found throughout this area. Although mest of the time this contamination was due to °°Co, several samples exhibited only unidentified 240 keV gamma-ray activity. rate would ita and is connected to west ng the -~ 39 - myeye 1! Er ne