Use of Geochemical Forensics to Determine Release Eras of Petrochemicals to Groundwater, Whitehorse, Yukon
Dates
Year
2005
Citation
Davis, A., Howe, B., Nicholson, A., McCaffery, S., and Hoenke, K. A., 2005, Use of Geochemical Forensics to Determine Release Eras of Petrochemicals to Groundwater, Whitehorse, Yukon: Environmental Forensics, v. 6, no. 3, p. 253-271.
Summary
At sites where petrochemical releases have occurred comparatively recently (i.e., over the last 20 years), explicit age-dating is a viable approach. However, differentiating among multiparty contamination at sites with several decades of history may mandate a different allocation strategy, especially when there is an uncoordinated body of environmental data. At a location where a refinery operated for 11 months during World War II, and which has been used as a fuel distribution terminal over the ensuing 60 years, regulatory interest was triggered in 1997 when a sheen was detected discharging into the adjacent Yukon River. Our investigation combined disparate forensic tools with data visualization software to establish the sources and [...]
Summary
At sites where petrochemical releases have occurred comparatively recently (i.e., over the last 20 years), explicit age-dating is a viable approach. However, differentiating among multiparty contamination at sites with several decades of history may mandate a different allocation strategy, especially when there is an uncoordinated body of environmental data. At a location where a refinery operated for 11 months during World War II, and which has been used as a fuel distribution terminal over the ensuing 60 years, regulatory interest was triggered in 1997 when a sheen was detected discharging into the adjacent Yukon River. Our investigation combined disparate forensic tools with data visualization software to establish the sources and extent of nine distinct groundwater plumes/product areas and to estimate their periods of release. Plumes were spatially identified based on solute distribution. Earliest Demonstrable Inception Date (EDID) and Latest Possible Initiation Date (LPID) were determined based on petrochemical additives: lead and its derivatives (MTEL, TEL, and TML); MTBE, TAME, and MMT; isotopic ( super(13)C/ super(12)C) and n-C sub(17):pristane ratios; SIM DIS curves; and aerial photography. Of these, aerial photography and additive history proved the best attribution methods to identify the EDID/LPID. This approach appears to be a useful tool when there is a long history of releases, but caution is necessary in interpreting potentially mixed plumes from different eras.
