than reported previously, their concentrations are rather high when compared with recent 
reliable data for these metals in open-ocean waters. For example, typical open-ocean 
surface concentrations of copper are 1 to 2 nmol/1 per liter. Typical clean coastal water, 
on the other hand, contains 2 to 3 nmol/1 per liter of copper. 
The distribution of copper in Boston Harbor reported by Wallace et al. (in press) is of 
particular interest. The distribution of copper at low tide, shown in Figure 10, provides 
three important pieces of information. First, at all stations sampled, the concentration of 
copper exceeded the current EPA standards for marine waters of 2 pg/1 (31.5 nmols/1). 
Second, concentrations in the southern parts of the Harbor were in excess of 200 nmol/1, 
among the highest reported in the reliable literature for estuarine and coastal waters. 
Finally a sample taken directly from the Deer Island plume contained, as expected, a 
higher copper concentration than observed at adjacent stations. 
High concentrations of copper were also Qbserved in the Inner Harbor and may 
reflect a combination of local sources and/or longer residence times of water in the Inner 
Harbor. Unfortunately, our ignorance of the dynamics of metals in Boston Harbor is 
coupled with our ignorance of the physical oceanography of Boston Harbor. Except for 
some initial studies in the vicinity of the Deer Island and Nut Island discharges, virtually 
nothing is known about the physical circulation in the Harbor. 
Perhaps the most remarkable feature of the copper distribution in the Harbor was 
the high concentrations observed in the southernmost areas of the Harbor. These high 
concentrations may reflect a combination of geomorphological, chemical, and biological 
parameters. For instance, the shallow nature of the southern Harbor, coupled with 
biogeochemical remobilization of copper from particles accumulating in the underlying 
sediment may account for this observation. We should also note that the remobilization 
of copper from sediments may involve temporal scales of days and perhaps even hours. 
Recent data on the kinetics of nutrient fluxes from sediments (Garber, 1984) support this 
hypothesis. The possibility that such rapid remobilization might happen is not generally 
considered when assessing impacts of waste disposal in the nearshore zone. 
Finally, with the high ambient concentration of copper in the Harbor, it becomes 
obvious that any discharge of copper to Boston Harbor waters from any source would 
probably violate EPA Water Quality Criteria. The discharge from Boston's new secondary 
plant, when constructed, may therefore have to be located further offshore to meet these 
standards. Unfortunately, the chemical speciation, toxicity, and transport and fate of 
copper and other metals in the Boston Harbor/Massachusetts Bay area are not understood. 
Until such knowledge is obtained, decisions regarding matters such as the extension of the 
outfall, a decision involving hundreds of millions of dollars, must be made in ignorance. 
Knowledge of the sources, distribution, and processes influencing the fate of metals 
in Massachusetts Bay is also non-existent. Evidence that metal concentrations in 
Massachusetts Bay sediments are higher than those observed in clean areas has already 
been presented. However, because of our limited knowledge in the above mentioned 
areas, we cannot make reasonable judgements concerning the potential influence of 
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