SOME DESIGN ASPECTS OF TRANSURANIC FIELD STUDIES R. 0. Gilbert and L. L. Eberhardt Battelle Pacific Northwest Laboratory, Richland, WA ABSTRACT In this paper, we discuss some design aspects of transuranic field studies. Some of the principal steps in the design of such studies are given and illustrated using examples. This is followed by a review of sampling designs that have been used at nuclear detonation and safety-shot sites on the Nevada Test Site and elsewhere for estimating spatial pattern and total amounts in soil. Some design aspects of ecosystem-type transuranic studies for estimating total amounts as well as movement of transuranics between ecosystem components are also discussed. Acceptance sampling using either attributes or measurements is considered as a possible approach for deciding whether to clean up a contaminated site. Three general guidelines for the design of efficient transuranic studies are presented. INTRODUCTION The design of a transuranic field study depends on a number of factors including objectives, the quantity, kind, and properties of the radionuclides present (related to the source of contamination), the spatial distribution of the contamination over the study site (trends, hot spots, etc.), and a variety of practical considerations involving budget limitations, size of the study site, time allowed for the study, ete. As a consequence, field sampling designs are necessarily site specific. However, there are general guidelines that can be used to help design efficient transuranic field studies. These guidelines are based on statistical methodology developed for sample surveys in other areas of application and on experience in designing transuranic studies. The design of any transuranic study should begin with careful planning well in advance of the actual collection of fleld samples. The first step is to carefully specify objectives. The second step is to define the "population" to which inferences are intended to apply. When these essential steps have