RIASSUNTO
Abstract
Any mineral exploitation from sea water or from the floors of estuaries, bays, or the adjacent continental shelves will almost always involved a disturbance of the natural marine environment and an alteration of the marine ecology. Where these operations impinge upon man's other activities or harm a beneficial use, consideration must be given to potential harm and steps taken to minimize or eliminate the injurious factors.
Potential pollutants from ineral activities include heat, turbidity, settleable solids, toxicants, deoxygenators, tainting substances, and growth nutrients as well as materials such as acids or bases which will change the chemical composition of the sea water. The pollutants are environmental stresses which, when combined with other stresses, can be harmful at diminished levels.
Although most activities are localized and the pollution is also local, consideration must be given to massive discharges caused by accidents or catastrophies. Particular attention is now required for operations conducted in United States waters which must meet new state and federal regulations.
The activities in the Santa Barbara Channel in recent months indicates the importance that environmental pollution can have in marine mineral exploitation.
Introduction
It has been generally assumed that the ocean is so vast and the water circulation is so good that all of the waste products of mankind could be discharged into the sea without any noticeable effect, provided only that the points of discharge were distant enough from shore. This reasoning was valid as long as the volume of the discharge was small and its toxicity slight. We now understand, however, that such an assumption was a great oversimplification. The explosive growth of our population, especially in areas near the ocean, the rapidly creasing volume of our waste products and our increasing dependence on marine resources have all made a careful consideration of marine disposal absolutely necessary.
The world ocean has been the repository for soluble and particulate material brought down in rain and washed into the sea from rivers for billions of years. It is still the final resting place for almost all of the waste products that we discharge into streams or into the air. Ultimately, all discussions of pollution and its effects must end with the ocean.
Mining ventures in the marine environment have some specialized pollutional aspects, as well as the same general effects produced by any industrial operation. In general, the principal mining problems are caused by the alteration of the environment when a naturally present material is removed. The nature of sea water and the characteristics of the liquid ocean require that thought be given before an peration is begun of the possible results and how they can be minimized.
Something About the Oceans
Although the world ocean is staggering in its immensity, covering nearly three-quarters of the surface of the earth to an average depth of more than two miles, we are really concerned only with the edges where the continents and the waters of the sea meet.
Since mining technology does not, at present, permit us to venture into the deep ocean with any substantial effort, any marine mining venture will be conducted either on the continental shelf or in an indentation along the oceanic periphery.