10-3 



Co and Ag in the major Connecticut rivers that the dissolved trace-metal 

 concentration is maintained at low levels in stream water and thus the 

 primary mode of transportation to the estuarine zone is via particles. 



Our work on the Quinnipiac River, a river carry inq effluents 

 from the major metal industries of Meriden and Wallingford and entering 

 into New Haven Harbor, supports this expectation. Figure 10-1 shows the 

 distribution of total silver in Quinnipiac River waters and demonstrates 

 an increase in concentration through Wallingford. In Wallingford, the 

 >0.45pm fraction (associated with particles) adds to the 3 pg/1 delivered 

 from the uncontaminated reservoirs. 



Figure 10-2 shows that the bottom sediments of the system are 

 strongly impacted by the trafce-metal injections from industry. The 

 remarkable feature of the observed pattern, however, is that the concen- 

 trations of Ag, Pb and Cu decrease almost to ambient precontaminated 

 sediment values shortly after the point of impact. This is probably due 

 to the presence of a series of small dams along the Quinnipiac River 

 that allow the metal- laden particles to settle out. 



The Housatonic River, emptying into the Sound about 15 km to the 

 west of New Haven Harbor, with its heavily polluted tributary, the Nauga- 

 tuck River, as mentioned above, supplies a significant amount of trace 

 metals to the adjacent part of the Long Island Sound, mainly in particle 

 form (Turekian, 1971) . In contrast, as noted above, the Quinnipiac River, 

 although also polluted by metals, appears to be retaining the metal-contami- 

 nated sediments behind a series of dams. The stream transport of trace 

 metals to New Haven Harbor and on to the Sound is minimal compared to sources 

 in the harbor itself as we shall see. The role of damming is certainly 

 one important factor in inhibiting transfer of metal-polluted sediments to 

 the estuarine zone. 



Sewer Outfalls - New Haven Harbor 



Applequist, Katz and Turekian (1972) showed that the mercury 

 concentration in the sediments of New Haven Harbor varied in relation to 



