FY 1988

Sources and sinks of Pb, Cu, Zn and Mn in the main basin of Puget Sound

Paulson, A.J., R.A. Feely, H.C. Curl, Jr., E.A. Crecelius, and G.P. Romberg

NOAA Tech. Memo. ERL PMEL-77, NTIS: PB88-219464, 26 pp (1988)

Municipal, industrial and atmospheric sources contributed 66% of the total Pb added to the main basin of Puget Sound. Advective inputs were the major sources of total Cu and Zn ( 40%) while riverine and erosional sources contributed about 30%. The discharge of the particle-bound trace metals from rivers minimized the impacts of particulate anthropogenic sources, which constituted 50%, 23% and 18% of the total particulate Pb, Cu and Zn inputs, respectively. While advective transport was the major source of dissolved Cu and Zn ( 60% of all dissolved inputs), industrial, municipal and atmospheric inputs contributed 85%, 30% and 38% of the dissolved Pb, Cu and Zn inputs, respectively. Diffusion of dissolved Mn was the major source of Mn to the main basin. About 75% of the dissolved Pb discharged into the main basin of Puget Sound was lost from the dissolved phase and was balanced by a similar gain in the particulate phase. Because of the effective retention of particles within the main basin, extensive scavenging resulted in about 70% of the total Pb added to the main basin being retained in the underlying sediments. The sources of dissolved and particulate Cu and Zn were comparable with the sinks within the errors of the analyses indicating their quasi-conservative nature. Advection removed about 60% of the total Cu and Zn added to the main basin while 40% was deposited in the sediments of Puget Sound. The rapid oxidative precipitation allowed only 10% of the dissolved Mn added to the main basin to leave the main basin in the dissolved form.