326 



Pacific Southwest regions ; fortunately these regions both have moder- 

 ate water temperatures which make possible efficient use of the avail- 

 able cooling water. 



There are, however, 47 nuclear powerplants built or scheduled for 

 completion by 1976. All of these are in the megawatt range, with 

 a combined capacity of nearly 35,000 megawatts of electrical power. 

 While the bulk of these will be in the cooler parts of the Nation, 12 will 

 be in the South Atlantic, Gulf, and Caribbean regions where water 

 temperatures are high, greater volumes must be used to achieve proper 

 cooling, and the increase in water temperature through the powerplant 

 may be sufficient to cause environmental damage. 



WASTE DISPOSAL 



The concentration of population and industrial development in the 

 estuarine zone has led naturally to the use of estuarine waters for 

 removal of the waste materials of man's civilization from his immedi- 

 ate vicinity. It is unlikely that cities were built on the coastline with 

 any conscious consideration of the use of the estuarine environment 

 for waste disposal, yet it has happened that this use has become one 

 of the major uses of estuarine waters and the associated land. Virtu- 

 ally all of the cities and industries in the costal counties dispose of 

 wastes either directly or indirectly into the estuarine zone. 



Liquid waste discharges to estuarine systems include domestic waste 

 products, industrial waste materials of all degrees of chemical com- 

 plexity and sophistication, used cooling water with its thermal load, 

 and storm runoff. These wastes affect the estuarine environment in 

 different ways and can eliminate other uses. 



Liquid wastes are not the only concern. The use of the estuarine 

 shoreline for refuse dumps and landfills results in considerable debris 

 getting into the water; water leaching through these dumps has a 

 pollutional impact on the estuarine water. Spoil disposal from dredg- 

 ing activities is another form of solid waste material that contributes 

 to estuarine degradation, and solid materials entering the estuary in 

 the form of debris from storm runoff can be significant in terms of 

 damaging beneficial uses. 



Waste disposal is a highly significant and universal use of the estu- 

 arine resource and it is likely to remain so. Along with the many other 

 socioeconomic uses of the estuarine environment, it must be managed so 

 that it does not damage the biophysical environment. 



EXPIiOITATION OF MINERAL RESOURCES 



Minerals within the water, on the bottom, and under the bottom are a 

 valuable part of the estuarine resource and are being exploited widely. 



Subbottom mining operations are limited to the recovery of sulfur, 

 petroleum, and natural gas, with the major operations occurring in 

 Louisiana, Texas, California, and Alaska. These operations exist both 

 in the estuaries and out on the Continental Shelves with the govern- 

 ing criterion for location being the location of reserves. 



Recovery of minerals from submerged estuarine zone bottoms by 

 surface mining; i.e., dredging, is primarily directed toward sand, 

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



