of Dr. Donald Jones, LLL H&S. Data interpretation, evaluation and reporting were accomplished by Drs. P. H. Gudikson and D. Jones, and Mr. O. D. T. Lynch, Jr. Presurvey Plarninzg - Background Studies 4 The testing program impact on the Eniwetok environment complicates any realistic attempt at evaluation. To formulate a practical survey plan, all available information had to be reviewed. Background information was obtained from all possible sources. The laboratories which conducted the experiments had reports and data on the original nuclear devices, their composition, associated experiments, ete. Actual test information, fallout patterns, radiological safety reports, etc., came from AEC sources, in-house. Construction drawings and information on modifications to the topography were available from the testing support contractor, Holmes & Narver, Inc. (H&N). Other organizations, including the various universities which conducted environmental studies during and after the testing program, had subsequent survey information. Several organizations had personnel who were associated and located at Eniwetok Atoll during the test operations. There was a wealth of information available in old reports, records, documents, etc., stored in archives. This information provided insight into what conditions could be anticipated and/or encountered. Much useful information was forthcoming, along with some anticipated problems: contradictory statements and reports. On the whole, the effort was very successful and was a deciding factor in the development of the soil sampling and terrestrial radiation survey programs.