Spatial variability of fallout Caesium-137 in Austrian alpine regions

As part of the Austrian soil contamination survey, total process standard d eviations of soil deposition measurement originating from spatial variabili ty of fallout deposition and measuring uncertainties have been determined. The total coefficient of variation (CV) of Cs-137 fallout in a 1 ha area, m easured by soil core sampling, amounts to 21.5%. The measuring process cont ributes with 12.2% leaving a 17.7% CV purely due to spatial variability of the fallout. Representativity of the measured contamination is being assess ed by calculating confidence intervals (95%), which vary between +/-25% and 42% of the measured values for different sampling methods used for the sur vey on which the Austrian caesium map is based. (C) 1999 Elsevier Science L td. All rights reserved.