Beta and Gamma Comparative Dose Estimates on Enewetak Atol] K. W. Crase, P. H. Gudiksen, and W. L. Robison ABSTRACT Enewetak Atoll is one of the Pacific atolls used for atmospheric testing of U. S. nuclear weapons. Beta dose and gamma ray exposure measurements were made on two islands of the Enewetak Atoll during July-August 1976 to determine the beta and low energy gamma contr ibution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable Nal detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a beta attenuator indicate that approximately 29% of the total dose rate at 1 meter in air is due to beta or low energy gamma contribution. Studies on the effect of ground cover on this contribution indicate that it is relatively insensitive to thickness of ground cover. Integral 30-year external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey (EN73). Integral 30-year shallow external dose estimates are 25 to 50% higher than whole body estimates. Due to the low penetrating ability of the betas or low energy gammas, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose, “Work performed under the auspices of the U.S. Department of Energy by the Lawrence Livermore National Laboratory under contract number W-7405-ENG-48." - 5004291