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resulted in the selection of possible damsites at Miles 29.9, 32.4, 32.8, 37.5, and 39.5. Profiles and geologic sections of these river sites were made, and from these data preliminary engineering studies eliminated the sites at Miles 29.9 and 32.4. Of the remaining sites, Miles 32.8, 37.5, and 39.5, all indicated foundation materials suitable for a concrete dam. The Mile 37.5 site was considered inferior because of a badly eroded joint system behind the left abutment, and was, therefore, eliminated from further field studies. During a 4-year period, from 1950 to 1953, both field and office investigations were conducted at Miles 32.8 and 39.5. Extensive drilling and mapping of both sites, as well as reconnaissance estimates prepared by the Chief Engineer's office, revealed both sites to be suitable for a concrete dam. Further economic and engineering studies resulted in the selection of the Mile 39.5 site. A dam at Mile 39.5 would develop approximately 30 feet more power head, and provide about 114, 000 acre-feet more storage capacity than could be obtained from a similar dam at Mile 32.8. This additional power head and reservoir capacity would create approximately $3,000,000 more annual power benefits, with no decrease in the project's benefit-cost ratio. Alternate sediment-retention damsite--Reconnaissance field studies were made of several possible locations of a sediment-retention dam on the Paria River and its tributaries before a final site was selected. The Paria River site was selected because studies indicated that the cost of obtaining adequate sediment storage capacity by the construction of a dam at this site would be less than that of dams located at other sites. 38Epson Perfection 4870 Photo, 400 dpi, 8 bit, 14,348,288 byte