TABLE OF CONTENTS TEXT If. INTRODUCTION. 2... ccc cee ce tee eet eee eee twee eee 1 INSTRUMENTATION, DATA COLLECTION AND ANALYSTIS....... 4 A. Instrumentation... eee eee eee eee eee tte eee Spectrometer System. ..... cc eee tee ee eee eee Ionization Chamber... ..... cc eee ee ee ee ee eens Portable Scintillation Detector........... eee eee G. M. Survey Meters... .... cc wee cee ee ee eee ee eee Thermoluminescent DoOSimetersS...... ce eee eee eee eee 5 5 5 6 7 8 B. SOil Sampling. ..... cece eee eee ee ee ete tee ee eee 10 C. Error Estimates and Data Evaluation.............. 13 ITI. EXTERNAL ENVIRONMENTAL RADIATION ON BIKINI ATOLL....15 A. Bikini Island... ... cece cee ee ee ee tte 16 Total and Individual Tsotope Exposure Rates Along the 0 TranSect....... cece eee eee ee ee eae 17 Total and Individual Isotope Exposure Rates Along the Village Road Transect...........+000.% 22 Total Exposure Rates Along the 1 Transect....... »23 Total Exposure Rates Along the South and North End TransectsS..... ec cee eee eee ee ee ee eee eee 24 Neeiyetll Whang Error in Total Gamma-Ray Exposure Rates.......... 13 Error in Partial Exposure Rates for Major EMLtters. .. cece ee ee ce ee eee eee eee ene eee 13 Error in TLD Results..... cc... eee eee eee ee eens 14 Overall Consistency of Data... ... ccc eee eee ee eee 14 Wee ad here Page Total and Individual Isotope Exposure Rates at hemaad hag 9 the Clearing Experiment Site..................6- 24 Summary of Exposure Rates on Bikini Island.......28 B. Eneu C. Bokantuak, Iomelen, Rojkere, Eonjebi............. 31 %, 4 \ tae