FY 1982

Elemental composition of suspended particulate matter in the lower Duwamish River and Elliott Bay, Washington

Massoth, G.J., R.A. Feely, and M.F. Lamb

NOAA Tech. Memo. OMPA-17, Boulder, CO, 41 pp (1982)

The distribution and trace element compositions of suspended-particulate matter in the Duwamish River and Elliott Bay were determined from samples collected in February 1980. The results show significant enrichments of Fe, Cr, Ni, Cu, Zn, and Pb in suspended matter from the Duwamish River estuary which is attributed to flocculation processes. In Elliott Bay the trace-element-enriched particles from the Duwamish River form a narrow plume that flows north across the inner Bay and westward along the northern coast where it eventually disperses into the outer Bay and central basin of Puget Sound. In subsurface and near-bottom particulate matter from Elliott Bay significant correlations exist between a number of the trace elements and manganese. These data suggest that newly formed hydrous manganese oxide coatings in the subsurface particulate matter effectively scavenge several trace elements, including Cr, Ni, Cu, Zn, and Pb. The biological implications of these results are discussed.