10-41 



As the long time-scale study (Table 10-4) covers several years 

 which bracket the construction and operation of the New Haven Harbor 

 United Illuminating power plant, it is evident that the impact of this 

 plant on the biota of the region is not measurable so far as the trace 

 metals are concerned. 



SUMMARY AND CONCLUSIONS 



Long Island Sound 



Trace metals are supplied to Long Island Sound by three path- 

 ways: (1) atmosphere, (2) metal-rich particles from contaminated undammed 

 streams directly leading into the Sound and (3) trace-metal-rich organic 

 particles derived from sewer outfalls that debouch into harbors. 



Mussels and oysters growing on hard substrates along the 

 shores of Lo^g Island Sound utilize and reflect the trace-metal- 

 enriched particles associated with the second two sources. ) 



These trace-metal-rich sources also imprint themselves on the 

 bottom sediments although the bottom circulation in the Sound tends to 

 mobilize and homogenize the sediment at the sediment-water interface. 



Over a long timeframe the sediments of the deeper parts of 

 Long Island Sound serve as the principal repository for trace metals 

 injected into the Sound due to the higher frequency of deep distribution 

 by Crustacea in sediments found in deeper waters. 



New Haven Harbor 



Trace metals enter New Haven Harbor from the Quinnipiac 

 River, major sewer outfalls located near Long Wharf and New Haven Harbor 

 Station as well as from the atmosphere. The dominant source is the 



