Radiological survey of Johnston Atoll. Dates of survey: April-August 1980. Revision 1

A radiological survey was conducted over all land areas of Johnston Atoll between April and August 1980. The survey was performed to locate and quantify residual surface transuranic (i.e., plutonium and americium) contamination resulting from three THOR missile aborts which occurred during that portion of the 1962 atmospheric nuclear testing series conducted by the United States from Johnston Island. A high purity germanium planar detector was utilized to enhance the detection sensitivity for the 59.5 keV gamma ray from /sup 241/Am. Results are reported as equivalent surface concentration in units of nCi/m/sup 2/. Conversion factors are also included for several other assumed source distributions. Soil samples were obtained to determine plutonium-to-americium ratios. 7 references, 14 figures, 1 table.