The migration of the surfactant from the oil into the water phase (in 

 essence, the source of energy for spontaneous emulsification) comes from the 

 redistribution of materials. In order for this system to work in the field 

 as an oil slick dispersant, the surfactant must be brought into contact with 

 the oil phase initially, such as in crop dusting oil slicks. 



It is also interesting to note that as the surfactant diffuses through 

 the interface, there is a reduction in interfacial tension. Over the entire 

 oil/water interface, there are dissimilar values of interfacial tension due 

 to the somewhat random diffusion of the surfactant at varying sites along 

 the interface. Any difference in interfacial tension produces a spreading 

 pressure, tv, which causes rapid movements of the interface. This inter- 

 facial turbulence also aids in the dispersion of the oil into the water phase. 



CONCLUSION AND FUTURE OUTLOOK 



There is increased recognition that there is a role for chemical dis- 

 persants in minimizing damage from oil spills. The improved effectiveness 

 afforded by the self-mix dispersant system has been demonstrated. In addition, 

 several organizations are planning major field demonstrations of this type 

 of dispersant system. In these experiments, the water column will be sampled 

 in the environs of the dispersed oil in order to establish the rate of dilution 

 of oil concentration. The resolution of this important aspect (i.e., the 

 dilution and resultant toxicity of dispersed oil) will help place the various 

 laboratory bioassays, wherein dilution of the dispersed oil concentration 

 is not considered, in a more proper perspective. 



Conventional (mixing required) dispersants will continue to be used in 

 the immediate future where mixing energy is conveniently available and the 

 spill size is relatively small. Hardware (sprays, booms, mixing breaker 

 boards, etc.) have been well-developed for boat applications. In this regard, 

 some dispersants are now formulated as concentrates (high surface-active agent 

 content) for greater oil -to-chemical treatment ratios, thereby permitting 

 workboats to remain on station longer before having to replenish supplies. 



LITERATURE CITED 



Battelle Pacific Northwest Laboratory. 1973. Effects of oil and chemically 

 dispersed oil on selected marine biota - a laboratory study. Richman, 

 Washington. 



McAuliffe, CD., A.E. Smalley, R.D. Groover, W.M. Welsh, W.J. Pickle, and 



G.E. Jones. 1975. Pages 555-566 in Chevron Main Pass block 41 oil spill: 

 chemical and biological investigations. Proc. joint conf. on prevention 

 and control of oil spills. San Francisco, California. 



Oda, A. 1968. A report on the laboratory evaluation of five chemical additives 

 used for the removal of oil slicks on water. Ontario Water Resour. Comm., 

 Toronto, Canada. 



Rodina, A. 6. 1949. Bacteria as food of aquatic animals. Priroda 38:23-26. 



Smith, J.E. 1968. Torrey Canyon pollution and marine life. Cambridge 

 University Press, New York, New York. 



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