Ground penetrating radar investigations at the Lake Condah Mission Cemetery: locating unmarked graves in areas with extensive subsurface disturbance

Ground penetrating radar (GPR) was used to non-invasively map the location of unmarked graves within the Lake Condah Mission Cemetery in western Victoria as a means of siting future interments. This cemetery was associated with the former Lake Condah Mission (established in 1869) and continues to be an important site for local Indigenous people. It is anecdotally thought to contain more than 100 graves however only 26 are currently marked. The GPR survey identified an additional 14 probable unmarked graves as well as 49 other areas that may contain one or more unmarked burials. The extensive subsurface disturbance present at the site and the presence of many extant tree roots made the effective interpretation of the GPR data difficult. Despite this, it was still possible to delineate areas where no unmarked graves are present. This is an important outcome for managing the cultural heritage of the cemetery because it identifies areas where new graves can be emplaced in a culturally appropriate fashion. This demonstrates the utility of GPR as a means of effectively managing heritage sites containing unmarked graves, even when substantial subsurface disturbance is present.