5.6 Complementarity of laboratory and in-situ techniques

As it was mentioned before, in-situ techniques are useful to establish the spatial / depth distribution of the radioactive contaminants, including the identification of hot spots. In most of the situations, the more important information for a site assessment might be the distribution trends or the gradient of change in the measured values. 2D and 3D representation of the results can be of help to address remediation / clean-up actions and to optimize the costs of associated projects.

When the activity or dose rate levels exceeds the levels established for a particular verification (critical exposure dose levels, compliance to a remediation criterion, among other cases), a very accurate determination is of less relevance, and in-situ techniques might be the choice.

Laboratory analysis might serve to verify the accuracy of in-situ results, or to make an unequivocal identification of radionuclides in the cases of complex contamination. The investigation of effects of contamination on the flora, fauna or the population usually requires of measuring relatively low activity levels, and the use of laboratory analysis is then the only alternative.