A field method for measurement of Cs-137 contamination depth profiles is de
scribed. The method is based on the use of a collimated dip detector create
d as a gamma-ray probe: CSI(TI) scintillating crystal + PIN photodiode + fr
ont-end electronics. The presented method allows determination of specific
activity distribution with vertical spatial resolution of 5 cm. Exposure ti
me for one point in the distribution profile is less than 180 s if the leve
l of specific activity is more than 50 Bq/kg. This method may be applied fo
r efficient and quick inspection of a contaminated river's flood planes in
areas with leakage of radioactive wastes. Application of the method for suc
h a task gives an effective solution to obtain qualitative and quantitative
characteristics of contamination.