135 



duction as well as some new drilling. Yet, the company exploiting the 

 oil reserves has restored all abandoned well sites and taken special 

 efforts to make their facilities blend into the natural environment 

 (fig. IV.2.24). This example is an exception to general practice, but 

 nevertheless points out the resource exploitation is not necessarily 

 synonomous with environmental destruction. 



Recovery of minerals from submerged estuarine zone bottoms by 

 surface mining, that is, dredging, is primarily directed toward sand, 

 gravel, and oyster shell production. Sand and gravel operations are 

 prevalent throughout coastal areas wherever suitable deposits and a 

 market exist. Most sand and gravel dredging operations supply nearby 

 users; therefore, they tend to be distributed in relationship to con- 

 struction and to population. 



The concentration of population and industrial development in the 

 estuarine zone, the accessibility of estuarine areas for sand and gravel 

 dredging, and the efficiency of barge transport to coastal construction 

 areas all tend to increase the pressure on submerged estuarine sand 

 and gravel deposits, particularly as coastal shore deposits are ex- 

 hausted. While no data are available on the present relative impor- 

 tance of shore and submerged deposits in the various biophysical 

 regions, it is certain that all available sources of sand and gravel 

 deposits will be exploited intensively. 



Oyster shell production is an extremely useful construction material 

 in the Gulf of Mexico ,:)iophysical region. Twenty of the 22 million tons 

 of annual U.S. production are in the Gulf States with Texas and 

 Louisiana producing \he vast majority of it. The major oyster shell 

 deposits are in shallow embayments such as Galveston Bay, Tex., and 

 Mobile Bay, Ala. 



Phosphate rock is an important estuarine mineral resource; about 

 75 percent of the total U.S. production is in the estuarine zone of 

 Florida and North Carolina, particularly around Tampa Bay and 

 Pamlico Sound. Considerable deposits of phosphate rock underlie 

 much of the South Atlantic biophysical region, and these may be sub- 

 ject to future exploitation. 



Ocean water is a great reservoir of dissolved minerals, some of which 

 are extracted commercially. Installations in the estuarine zone in Cali- 

 fornia, New Jersey, Texas, and Florida extract magnesium compounds 

 from coastal ocean water and supply the bulk of U.S. production. Large 

 ponds are used in California for the evaporation of saline water to 

 produce commercial salt ; many of these have been built in marshes or 

 shallow estuarine waters. 



SHORELINE DEVELOPMENT 



The use or development of estuarine water either depends upon, or 

 governs, land or shoreline use. Examination of some of the purposes 

 of shoreline development illustrates this relationship. 



Recreational shoreline development is based on potential water 

 use. Recreational facilities included : Marinas which support boating 

 activities ; beaches which are necessary for the swimmers ; parks that 

 cater to those seeking aesthetic enjoyment of the water; fishing piers 

 and vacation cottages, motels, and hotels (fig. IV.2.13). Although 



42-847 O — 70 10 



