Remediation of Frozen Ground Contaminated with Petroleum Hydrocarbons: Feasibility and Limits

Petroleum pollution is a significant problem in cold regions. We define cold regions as Arctic and sub-Arctic, Antarctic and sub-Antarctic, and alpine regions that exhibit permafrost or seasonally frozen ground (Filler et al. 2008b). Encountered in gravel pads, roads, and abandoned waste dumps, at remote air strips, research stations, and legacy military and mine sites, with fuel storage and dispensing facilities, and as leaked or spilled product along transport corridors (i.e., pipeline and roads), petroleum is persistent in and difficult to remove from frozen ground. Economic limitations on cleanup are associated with remoteness, access (where regulated), scant local resources, and complex logistics. Physical changes to ground brought on by sub-freezing air temperatures reduce microbial activity and alter physicochemical properties of petroleum (e.g., partial pressures — aqueous/vapor phase partitioning — and volatility). We are beginning to understand freeze–thaw effects and cryoturbation in cold contaminated soils (Biggar and Neufeld 1996; Chuvilin et al. 2001; Barnes et al. 2004; Bigger et al. 2006; Barnes and Wolfe 2008; Barnes and Biggar 2008). Cleanup decision making is usually dictated by financial circumstances, regulatory pressure, perceived risks, and liability associated with lease responsibility or transfer of land ownership (Snape et al. 2008a). Ideally, a practical remediation strategy is chosen based on a feasibility study of alternatives, with consideration for sitespecific conditions, and acceptable trade-off between cost and treatment duration. From the responsible party perspective, the cost–time relationship (Fig. 19.1) is often the single most important aspect of decision making in environmental cleanup. The regulatory perspective also considers human and ecosystem health to be of paramount importance. Irrespective of stakeholder perspective, the development of cost-effective and timely remediation strategies benefits all. Figure 19.1 illustrates cost–time relationships for developed soil treatments that have been used in cold regions.