I am going to begin by stating the overall conclusions of the study, so that when I do 
present some of the information, you will be able to see how I arrived at these 
conclusions. A major conclusion of recent studies is that PCB levels in Boston Harbor are 
fairly typical for moderately polluted estuaries, such as New York Harbor and Buzzards 
Bay. PCB levels in Massachusetts Bay are elevated over a wide area, similar in overall 
distribution to the New York Bight Apex, which has been well studied. The PCB 
distributions are more widespread in Massachusetts Bay than they are in New York Bight 
Apex. The depositional basins in Massachusetts Bay are potential traps for PCBs, PAHs 
and other sewage-associated and harbor-associated material that may be transported from 
the coastal area to adjacent receiving waters. The PAH levels in Boston Harbor range 
from values fairly typical for polluted estuaries to some of the highest values reported 
anywhere. This fact is one of the major findings that I have discovered so far in Boston 
Harbor. In the Harbor, we find pockets of very high PAH levels that coincide with high 
coprostanol values. Coprostanol is a fecal steroid, an indicator of (mammalian) sewage 
input, and is often analyzed in sediments along^with toxic organic compounds as a tracer. 
The PAH loading in Massachusetts is similar to that of the New York Bight Apex. 
Offshore Massachusetts Bay and the New York Bight Apex are fairly similar in overall 
loadings of PAHs as determined from sediment concentration distributions. 
Other researchers have determined that the overall health of the region appears to 
be mixed, with degraded bottom habitats observed in the Harbor and sporadically 
offshore. The health of finfish is relatively poor and directly related to pollutant 
concentrations in the animals' habitats, the sediments from which they ultimately derive 
food. 
The residence time of contaminants in Boston Harbor is a key management 
parameter and is really not very well known. From data on other metropolitan harbors, 
such as New York Harbor, I estimate that the contaminant residence time in sediments is 
probably on the order of a decade or more. This raises the question: if we changed 
pollutant inputs, what type of recovery or response time will we observe for chemical 
loadings? It is probably on the order of a decade or more, rather than months or years. 
One of the mistakes we can make in considering toxic contaminant problems of 
Boston Harbor is to consider that sewage sludge inputs and sewage treatment plant inputs 
are the only potential source of toxic contamination in the area. This point does not 
minimize the importance of the sewage issue, but rather indicates that sources other than 
sewage outfalls are very important. All along the Boston Harbor shoreline and in the 
Charles River, there are also combined sewage overflows and other discharges. The 
impacts of riverine inputs, and the Charles River in particular, are not trivial. The 
Charles River is a major source of coliform bacteria and its sediments contain high levels 
of PAHs. 
Despite many studies in the Harbor, I think that our inability to understand the 
system has really been caused by a set of fairly myopic study plans. We have studied 
301(h) (secondary treatment water) problems and sewage outfall problems on a pipe-by- 
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