A standard operating procedure (SOP), for soil sampling, for the detection of volatile organic compounds and leachate associated with human decomposition from a shallow, unmarked, homicide grave

The aim of this paper is to provide a forensic geology standard operating procedure (SOP) for the collection of soil, for the detection of volatile organic compounds (VOC) and leachate associated with decomposing human remains in a shallow, unmarked, homicide grave. This assumes that human remains undergo partial or complete decomposition after burial and that the VOCs and leachate plumes generated subsequently migrate from the grave. These are expected to be influenced by several factors, including for example the cause of death, time elapsed since burial, climate and weather, topography, geological characteristics of the soils and bedrock, hydrogeology and taphonomy. This SOP has been used in a number of high-profile police and law enforcement searches (see for example Donnelly et al. 2020. Analysis of soil following a police-led open area search and the recovery of a cold case homicide grave, Forensic Soil Science and Geology, 492, https://doi.org/10.1144/SP492-2017-337). This approach remains experimental and further research and operational test work are recommended at known (recovered) homicide graves. This might become applicable as a future reconnaissance method applied to searches taking place over large areas to help reduce the preliminary search area where VOC and leachates are detectable.