Onderzoek naar de radioactiviteit van depositie. Resultaten over 1989

Abstract

This report summarizes the results of measurements of radionuclides deposited at Bilthoven in the Netherlands in 1989. The total depositions of H-3 (1560+-130 Bq/m2), Be-7 (740+-40 Bq/m2), Pb-210 (94+-7 Bq/m2) and Po-210 (24+-4 Bq/m2) were not substantially changed compared to those in previous years. The same applies to the deposited gross alpha- (43+-1 Bq/m2), gross beta- (89+- 3 Bq/m2), gross gamma-activity (128 +- 5 Bq/m2). The depositions of Cs-134 and Cs-137 were <2,6 Bq/m2 and <3 Bq/m2 respectively. In 1988 these depositions were <5 Bq/m2 and <6 Bq/m2. The weekly deposition of gross gamma-activity, H-3 and Be-7 were correlated with the amount of precipitation. In 1989 the consequences of "Chernobyl" were no longer perceptible in the deposition in the Netherlands.