UNCERTAINTY OF THE LONG-TERM RESUSPENSION FACTOR

Resuspension of contaminated soil into the atmosphere is one of the ke y processes that must be considered in the estimation of inhalation do ses to humans. Data for air and soil contamination collected in Ukrain e over several years since the Chernobyl accident have permitted analy sis of resuspension in terms of the underlying mechanisms. Various emp irical models for the resuspension factor as a function of time (e.g. Linsley, Garland, Anspaugh, etc.) are compared to the observed resuspe nsion factors over time (9 yr) at two sites; in general, these models give overestimates for the resuspension factor as a function of time. The observed values of the resuspension Factor range from greater than 10(-5) m(-1) at early time points to around 10(-10) m(-1) al later po ints. The uncertainty in the resuspension Factor is decreased to withi n 1 order of magnitude if annual averaging of the experimental data is used and ii the resuspension factor is determined as a function of ri me and of the predominant regional conditions of vegetative cover and climate. (C) 1997 Elsevier Science Ltd.