Industrial Stream Pollutionin Virginia A
PROGRESS REPORT
By STUART C. CRAWFORD, '38
Consulting chemist, whose stream pollution studies have won critical acclaim from experts in the field, Stuart C. Crawford, '38, has done notable work for' Virginia industries. He was singled out for high praise by L. L. Hedgepeth, executive secretary of the Virginia State Water Control Board.
T HE
abatement of pollution is primarily a technical problem. This prosaic statement is intended to emphasize the differences between the legal, ethical, and conservational aspects of the general subject of stream pollution, and the essentially technical considerations involved in the abatement of this nuisance . The failure to recognize such differences may seriously handicap the progress of corrective work. This is a controversal subject. And, as is usual with such issues, the proponents of all the various viewpoints have strong arguments. Yet it is doubtful if arguments will ever settle the matter to anyone's satisfaction. Since the beginning of agitation for the correction of polluted streams the procedure has been largely that of "choosing up sides." The conservation-minded individual is regarded as anti-industry. The industrialist is pictured as one who delights in the ruination of the waterways of the nation. Now, who can win such an argument? A brief consideration of the mechanisms resulting in pollution of streams may not be amiss. One eminent authority has proposed viewing the subject in the light of a financial balance sheet. Stripping this approach to its essential considerations it may be viewed simply as Assets vs. Liabilities. The assets may be regarded as the oxygen resources of a stream. Some of the contributing factors to this side of the balance
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sheet are natural character of the water , quantity and turbulence of flow, and natural biological population. After assessing the positive value of such components the natural solvency of the river may be evaluated. Against the assets must be charged the various sources of pollution. Normally these may be defined as natural sources, meaning decay of vegetation, and related sources, sanitary sewage as representing the wastes from municipalities, and finally the wastes resulting from industrial operations. Also, the nature , extent, and frequency of the sources of pollution must be considered . Obviously, the problem is one of degree. Thus the matter may be summed up as follows: the stream may be unquestionably solvent with present assets exceeding all liabilities; it may be solvent with present assets plus anticipated revenue exceeding all liabilities; another degree may be represented as temporary solvency with anticipated liabilities foreshadowing an inevitable bankruptcy; finally , present insolvency may be the case. When viewed in this manner the problem becomes simple and a definition of pollution is clearly evident. When one's liabilities exceed the assets bankruptcy results. In a stream this is called septicity . The problem of correcting an existing pollution condition is mainly dependent upon the source of the pollution. This separates the field of municipal from that of industrial waste treatment. The science pertaining to evaluation and treatment of domestic wastes is relatively well established as a branch of sanitary engineering. Such is not true when dealing with industrial wastes. The conventional methods employed in sanitary engineering are not usually applicable without modification. New approaches must be developed which may vary from industry to industry as the nature of the wastes changes. And added complication results when the over-all picture is a combination of domestic and industrial wastes. Usually this is the situation . When the stream sanitarian is confronted with an undesirable industrial condition his task is no different from that of any other technical man confronted with a problem. First , he must ferret out and measure the individual sources causing the pollution. Then he must define and ~valuate the problem in acceptable units of measurement. Second, all feasible remedial steps must be taken within the plant to diminish the original problem. Third, a method of treatment must be devised to render the balance acceptable to the receiving stream. Concurrently with this program a definitive study of the characteristics and behavior of the stream must be made . This will provide final criteria by which the success of the endeavor may be determined. It is a slow and tedious study. What takes a paragraph to write may have taken years to determine. This is due to the magnitude of the average industrial problem. "Population Equivalent" is the common denominator used to compare all types of wastes. The following data published from the United States Public Health Service emphasizes the complexity of the industrial problem.
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