208 



Models often are kinematic and not dynamic. Time to reach equilibrium 

 is not considered (time dependence) . 



Impacts of change in storminess need to be modeled. Perhaps we can 

 use historical data. 



Laser technology for profiles does not appear to be the most useful 

 technology. 



We need to consider impacts of change in sediment availability and 

 freshwater inflow. How does global climate change impact sediment supply? 



The major issue appears to be oversteepening of the inner shelf. This 

 has many people concerned. Is this a valid concern or just a red herring? 



Onshore sediment transport is a potential source of stability to 

 beaches . Does onshore (midshelf shoreward) transport really exist? Theory 

 and observations both are ambiguous regarding this factor. 



Improved understanding of beach nourishment procedures is required. 



SECT. 8. SALTWATER INTRUSION 



The impact of varying recharge and discharge from aquifers must be 

 significant, particularly for phreatic aquifers (unconfined) on islands or 

 peninsulas. On Cape Cod, for example, increased discharge may well 

 dominate over any sea level effects. On the other hand, a 1-in. rise in 

 the phreatic surface will cause a depression in the saltwater interface of 

 40 to 50 in. ; increased recharge due to increased precipitation might 

 overcome effects of relative sea level. 



Tidal mixing along the saltwater/freshwater interface must be 

 understood better. This mixing is important to salt intrusion as well as 

 biological processes: nutrient exchanges, nutrient budgets, and other 

 biochemical interactions. 



Consideration must be given to effects of saltwater intrusion up 

 rivers on groundwater intrusion along the rivers. We cannot address just 

 the coastline. 



SECT. 9. UPRIVER SALTWATER PENETRATION 



We need increased understanding of the basic physics of intrusion 

 mechanics; e.g., mixing (including small-scale turbulence) across density 



