The fate of heavy oil wastes in soil microcosms II: a performance assessment of source correlation indices

Chemical fingerprinting is commonly undertaken to assist in the resolution of multi-party liability disputes, particularly when contaminants have migrated beyond property boundaries, in litigation-driven environmental assessments related to oil spills, and in assessing potential environmental impacts following releases of petroleum products into the environment. In this paper, we present data relating to the performance of source correlation indices for selected heavy oils over the course of a 9-month microcosm study. The results obtained in this study demonstrated that hopane pair indices varied little in magnitude, and may therefore be considered reliable source correlation indices. Over the course of the 9-month microcosm study [17α(H)21β(H)-norhopane: 17α(H)21β(H)-hopane] exhibited mean values of 0.7±0.1 for a heavy ballast oil, and mean values that varied between 0.6 and 0.7 (±0.05) for a crude oil. Similarly [(17α(H)21β(H)-homohopane (22S): 17α(H)21β(H)-homohopane (22R)] gave a mean value of 1.3 (precisions less than 0.05) and [17α(H)21β(H)-bishomohopane: 17α(H)21β(H)-methylhopane] varied between 1.3 and 1.6 (precision up to 0.1) for the same crude oil. These source correlation indices may be used to support a correlation between fresh and weathered oil samples for source identification purposes involving heavy and crude oil contamination of the terrestrial environment.