Waste site characterization through digital analysis of historical aerial photographs

Abstract

Historical aerial photographs have been used to provide a physical history and preliminary mapping in forma tion for characterizing a Department of Energy waste burial site at Los Alamos National Laboratory. The photographs were digitally scanned in order to perform on-screen computer change detection. The digital analysis of these photographs allowed disparate views of the waste site to be transformed so that they matched in scale, orientation, and extent. This was especially useful for oblique photographs of the waste site. The coregistered images were studied individually (and in comparison with each other) to identify features which were indicative of human activity at the site and to provide a physical history of natural and human induced changes. The coregistered images were imported to a geographic information system and geographically coded to a common coordinate system. The geographic information system was used to extract the boundaries of features such as suspected trenches and disturbed soil. This preliminary analysis forms a basis for planning and comparing the results from other remote sensing and geophysical surveys which will be used to improve the characterization of the waste site.