INTRODUCTION We and individuals from several other organizations are engaged in a major, 4-yr project that has the goal of determining the radiation doses received by residents in the region of the Nevada Test Site (NTS). This complete evaluation wil? include doses received from external gamma and beta exposure due to the fallout field, from external gamma and beta exposure from immersion in the debris clouds, from beta exposure of the skin from direct deposition of fallout, and from internal exposure due to the intake of radionuclides via inhalation and ingestion. included. Al) activities conducted at the NTS will be It is not generally appreciated that tests of nuclear engines and ramjets were conducted at the NTS during the 1959 to 1969 period, and that these reactor tests released radionuclides to offsite locations. One of the important goals of this project is to understand the measurements that were made in the field at the times immediately following the detonations, and the methods of calculation that were used to translate these measurements into estimates of exposure and/or dose. Unfortunately, there was no major effort to calculate the dose that people received from internal emitters and this is a major part of our study. Some radionuclides, such as 905, I, and V37o6 | did receive major attention as time went on (JCAE63), but the available measurement techniques and assessment methods did not permit a complete evaluation. 202