1983 年 18 巻 1 号 p. 11-16
The influence of interstitial water velocity on the migration of Sr-85 and Cs-137 in an aerated sandy soil layer was studied at different feed water velocities and feed times. As well known, it was found that Sr-85 migrated with interstitial water, but Cs-137 little migrated with interstitial water. The apparent migration velocity for each fraction corresponding to three concentrations (2×10-2, 1×10-2 and 5×10-3μCi/g) of Sr-85 was further investigated. At constant interstitial water velocity (1cm/mm), different values were given for the apparent migration velocity of three fractions, and the fraction with thin concentration migrated faster. At constant feeding time (100hr), there was a linear relationship between apparent migration velocity of three fractions and interstitial water velocity, in the range of slow water velocity (<1cm/mim). However, there was no linear relationship between apparent migration velocity of two fractions (equal to the concentration of 1×10-2 and 5×10-3μCi/g) and interstitial water velocity, in the range of fast water velocity (>1cm/min).