31. 



considerably slower than predicted for free diffusion. 



Transport by ocean currents along the Atlantic coast of the 

 United States is reviewed in Appendix V. Our present knowledge con- 

 cerning the details of bottom circulation in shallow inshore regions of 

 the Atlantic coast is practically nil. In some areas we have fairly de- 

 tailed information concerning the surface circulation, and we have rather 

 broad hints as to the behavior of the bottom waters, but there is little 

 information detailed enough to permit a reliable, quantitative prediction 

 of the rate of flow shoreward and of the quantities of materials that will 

 be transported from a given disposal area. 



In general, disposal sites have been placed in areas in which the 

 predominant circulation, estimated from known or extrapolated surface 

 circulation, appears to parallel the coast, thereby making direct trans- 

 port to the immediate coast line improbable. 



Of special interest are the following features: (a) landward flow 

 of bottom water at the mouths of estuaries; (b) a general stagnation of 

 bottom water in a region south of Nantucket Shoals, during the approx- 

 imately six months of the year in which these waters are stratified; 

 (c) suggestion of a general shoreward movement of bottom water, in 

 the area from Virginia to New Jersey, during the summer months, and 

 a seaward flow during the winter; (d) a counterclockwise eddy in the 

 Gulf of Maine that may produce longshore non-tidal drifts of up to 6 



