New Method for Determining Degree of Pollution Described A STAFF I\EPORT J U D G I N G by the unexpectedly large a t tendance a t the fifth Industrial Waste Conference at Purdue on N o v . 29 and 30, industry is rapidly becoming seriously concerned with the problems of waste disposal. T h e sponsors of the meeting, anticipating a total attendance of about 300, were pleasantly surprised when they totaled up their gate to discover that it came t o almost 500, about 350 of whom were from outside the university. Observers who were familiar with attendance at previous meetings said that there was a much stronger representation from industrial organizations this year than there had been in the past. Several speakers on the program pointed out that there is a distressing difference between the volume of fundamental data available on sanitary waste which has been studied intensively by government laboratories for many years and that on industrial wastes which have only in recent years been the subject of comprehensive investigation. ISetc Assay Method In a program of highly specific discussions of individual installations, one individual fundamental contribution stood out. Ruth Patrick of the Academy of Natural Sciences of Philadelphia described a new biological assay method for determining the degree of pollution in natural waters into which wastes have been discharged. T h e biological oxygen demand or B.O.D. which has classically been one of the prime i n dexes of such pollution has been under attack for some years by fundamental scientists as unreliable and sometimes
Ruth Patrick oj the Academy of Natural Sciences of Philadelphia presents new biological assay method for determining degree oj pollution in water
misleading. Dr. Patrick's finding* tend to support this criticism and further to indicate that other chemical analyses» usually used in conjunction with B.O.D determinations can be equally mUloading. Starting from the assumption th.-n the undesirable· characteristic of pollution is that it destroys the normal floia and fauna in natural waters, Dr. Patrick based her method directly on an examination of aquatic growths. Hoi data tend to show that the number of species represented in each of seven groupings is significant rather than the number of individuals present in the species. Apparently polluting agents destroy individual species selectively. By comparing the changing ratios of these species numbers she has been able to classify waters from healthy to very polluted by a direct observation. These direct classifications d o not correlate with results of conventional derivative tests. Dr. Patrick submitted that if properly organized, the method could be used almost as cheaply a s present survey methods and it has the advantage of not presenting the insurmountable problem of determining and analyzing for every possible toxicagent or combination which may occur in industrial wastes. She also expressed the hope that certain indicator forms of plant or animal life could b e found which which would permit laboratory evaluation of exist-
How to control pollutants is the question as R- R. Baxter and S. E. Hancock of E. C. Schleyer Pump Co· and Ray W. Clark of LinkBelt Co· get together
VOLUME
2 7, N O .
51
» DECEMBER
19,
1949
ing stream conditions or of the efficacy of waste treatment processes. Papers by John E . Tarmen of W. H . & 1 . D . Betz, Consultants, and C. F . Waite of King-Seeley Corp., discussing various techniques for inactivating cyanide-containing wastes, gave chlorinalion with cither liquid chlorine or hypochlorites a clean lead in this field. Chlorination was also recommended for treatment of sugar beet processing water by E . A. Pearson of the University of California. This author claimed that in addition to the elimination of the mo>st objectionable pollutants, this treatment makes possible the recovery of considerable usuable sugar from the waste water. Wastes Can Pay Companies which have undertaken serious study of their waste problème have in some cases found that efficient techniques can actually save them money. R. G. Arner, in a paper added to the program, described the performance of a new waste disposal system brought into operation at the Sinclair Refining Co.'s East Chicago plant during the past summer which has cut the volume of effluent substantially and has resulted in a marked increase in \*olume of economic products from the refinery. A similar economic result was reported by J. R . McMahan of Chas. Pfizer & Co. in a description of a unit for handling wastes from their Terre Haute antibiotic production. Previously the extracted nutrient solut i o n from this process was discarded and required the addition of about 5,000 pounds of chlorine per day to make it suitable for introduction into public waters. By recycling this fluid and extracting solids which are salable as vitam i n Bis supplemental cattle food it has b e e n possible t o reduce the treatment requirements to about 300 pounds of chlorine per d a y ; this effects a double economic benefit.
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