Susquehanna River, Pennsylvania

In general, silver concentrations in surface waters of the United States decreased between 1970-74 and 1975-79, although concentrations increased in the north Atlantic, Southeast, and lower Mississippi basins (USPHS 1990). About 30 to 70% of the silver in surface waters may be ascribed to suspended particles (Smith and Carson 1977), depending on water hardness or salinity. For example, sediments added to solutions containing 2 pg Ag/L had 74.9 mg Ag/kg DW sediment after 24 h in freshwater, 14.2 mg/kg DW at 1.5% salinity and 6.9 mg/kg DW at 2.3% salinity (Sanders and Abbe 1987). Riverine transport of silver to the ocean is considerable suspended materials in the Susquehanna River, Pennsylvania — that contained as much as 25 mg silver/kg — resulted in an estimated transport of 4.5 metric tons of silver to the ocean each year (USEPA 1980). The most recent measurements of silver in rivers, lakes, and estuaries using clean techniques show levels of about 0.01 pg/L for pristine, nonpolluted areas and 0.01 to 0.1 pg/L in urban and industrialized areas (Ratte 1999). 

Five soils and leachate-sprayed soils from the Susquehanna River basin in Pennsylvania and New York had levels of di(2-ethylhexyl) phthalate ranging from 0.001 to 1.2 mg/kg (Russell McDuffie, 1983). Contaminated soil in the Netherlands was found to contain up to 1.5 mg/kg dry matter (Warns, 1987). Residues of di(2-ethylhexyl) phthalate in soil collected in the vicinity of a di(2-ethylhexyl) phthalate manufacturing plant amounted to up to 0.5 mg/kg (Persson et al., 1978). 

In addition, all young children were able to identify the representational meaning of at least some parts of the representations (understanding at the componential level, see Liben Downs, 1989, 1991). There were, however, confusions in distinguishing incidental from referential features. Sometimes the assumption of fully motivated symbols facilitated correct interpretations, as when children correctly identified the Susquehanna River on the road map of Pennsylvania as a river because it s blue or... 

Sites associated with the Clemson Island tradition date between A.D. 700 and 1300 and are largely found along the north and west branches of the Susquehanna River. Owasco sites generally date between A.D. 900 and 1300 and are concentrated in central and southern New York. The spatial distribution of Owasco sites minimally overlaps the Clemson Island tradition with a few camps reported in north-central Pennsylvania. The settlement patterns of these groups are oriented around agriculturally based hamlets and smaller resource procurement sites. 

St. Anthony s, Fisher Farm, and clay sample 5 are located in central Pennsylvania south of the West Branch of the Susquehanna River. This area is the heartland of the Clemson Island tradition and it seems reasonable that only Clemson Island sherds grouped here. 

The occurrence which has generated more public concern than any other is the well-known Three Mile Island accident. The reactor involved was the second unit of two located on an island in the Susquehanna River, near Harrisburg, Pennsylvania. The layout of the reactor circuit and ancillary systems is shown in Fig. 12.14. The sequence of events leading to the accident is given below. 

Buchanan, J.W. Loper, W.C. Schaffstall, W.P. Hainly, R.A. "Water Resources Data Pennsylvania Water Year 1983 Volume 2. Susquehanna and Potomac River Basins, USGS/WRD/HD-84/060,... 

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