R8 AM Contamination Source Identification and Apportionment
Thursday, 17 November 2005: 8:00 AM - 11:40 AM in 331-332

(SOW-1117-572296) Source contribution of bioavailable polycyclic aromatic hydrocarbons and the impact of seasonal and episodic events in the Willamette River, Oregon.

Sower, G¹, Sethajintanin, D¹, Grove, R^{1, 2}, Anderson, K¹, ¹ Oregon State University, Corvallis, Oregon² USGS Forest and Rangeland Ecosystem Science Center, Corvallis, Oregon

ABSTRACT- Concentrations of biologically available EPA priority pollutant polycyclic aromatic hydrocarbons (PAHs) along 18 miles of the lower Willamette River were determined by sampling water with passive sampling devices and analyzed using HPLC with diode array and fluorescence detectors. The study area includes the Portland Harbor (approx. river mile (RM) 3.5 – 9.5) and McCormick and Baxter (RM 7) superfund sites. Designated as a superfund site in 2000, Portland Harbor is a heavily industrialized stretch of the Willamette contaminated with heavy metals, polychlorinated biphenyls (PCBs), dioxin/furans, pesticides, and PAHs. Within Portland Harbor lies the former wood treating site of McCormick and Baxter which was designated a superfund site in 1994 and is characterized by soil, sediment and water contamination by PAHs, penta-chlorophenol, and heavy metals. Additional potential sources of PAHs include urban runoff, fires and spills. Fluoranthene to pyrene and phenanthrene to anthracene ratios were used to help identify sources. These ratios varied spatially and temporally at almost all sampling sites suggesting that the major sources of PAH contamination vary depending on several factors including, but not limited to, precipitation and river flow levels.

Key words: PAHs, SPMD, passive sampling, source apportionment