ABSTRACT

The concentrations of ²³⁸Pu and ^{239, 240}Pu were measured in surface air and rain samples collected at Fayetteville (36°N, 94°W), Arkansas, during the period between October 1971 and November 1973. The ²³⁸PU/^{239, 240}Pu ratios in many of the samples were found to be in the range between 0.1 and 0.3. These results indicate that appreciable amounts of ²³⁸Pu are being injected into the atmosphere by the recent nuclear weapons tests.