Shoreline Erosion 
Metals composition has been measured in very few soil samples. Data 
from three studies were used in conjunction with the reported 
composition of "average earth's crust" to determine representative 
values of Puget Sound shoreline soils. Concentrations of PAH's and 
PCB's in regional soils were assumed to be equal to zero. 
Atmospheric Inputs 
Inputs of metals and organics resulting from atmospheric transport and 
deposition have received very limited study. Lead and total suspended 
particulate data are most readily available for a number of Puget Sound 
stations. Metals data available for airborne dust collected at the 
University of Washington were also available. The ratio of lead to 
other metals in this dust was used to estimate ambient metals 
concentrations in other areas. PAH concentrations were also estimated 
from a single study and the assumption that the PAH input is 
proportional to the input of atmospheric lead. 
Municipal Discharges 
Considerably more data are available for the major municipal sewage 
effluent discharge then for other sources. However, little data exist 
for many of the smaller discharges. Therefore the concentrations of 
metals and organics reported in the Metro TPPS report were considered 
to be representative of all Puget Sound Municipal discharges. 
Industrial Discharges 
Available NPDES monitoring and inspection reports were used to estimate 
metals concentrations in industrial discharges. Available data were 
not adequate to estimate industrial inputs of organic compounds. It 
should be noted that the major contribution of metals to Puget Sound 
from industrial effluents was the ASARCO smelter near Tacoma. Which is 
now closed. Other significant industrial inputs were the pulp and 
paper mills which may have made an even greater contribution prior to 
implementation of secondary treatment facilities in the mid-1970's 
(Quinlan et al. 1985, pg. 74). 
The total Puget Sound inputs for the selected priority metals and 
synthetic organic chemicals associated with the various sources are 
presented in Tables 1 and 2. It is apparent that metal inputs are 
dominated by the major nonpoint sources (riverine and shoreline 
erosion). The large contributions of metals from shoreline erosion 
reflect the fact that the metals are natural elements present at 
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