. Dr. James L. Liverman -4- August 17, 1977 Ocean dumpin~~as considered to be the preferred solution by most of the reviewers. While the. quantities-of soil and debris are high (75,000225,000 yds3), the plutonium inventory is estimated to be only in the order of 20 Ci, an insignificant smount to dump into the Pacific Ocean compared to that which is already present in the ocean from weapons test fallout. Presently 3-4 Cl is transported from the waters of the lagoon to the open ocean each year. We understand that EPA interprets PL 92-532 to effectively prohibit ocean dumping by the U.S. H&ever, the U.S. has contributed technical guidance and is signatory to the international agreement on the dumping of radionuclides in the ocean under the London Convention which “allows” dumping of much larger quantities than 20 Ci of plutonium. Advantages of deep ocean dumping include the removal of the plutonium completely from the Atoll environment and the elimination of the need for any future monitoring and maintenance. However, the EIS would probably have to be reopened and an oceanographic survey. performed. Lagoon dumping as an acceptable aitermate ta Gceaa dumping minimizes international ramifications. Since .soil would be slowly dispensed to the lagoon during the cleanup and only a small fraction of the bound plutonium will be remobilized, the actual impact on the lagoon water concentration till be slight. It can be demonstrated by computation that less than 0.01% of the plutonium would be remobilized to the . solution phase during disposal to the lagoon. The majority of material would settle to the floor of the lagoon. Concentrations of plutonium in aquatic organisms might increase, but since the residence time for sea water in the lagoon is about 150 days, the concentrations would shortly be reduced to smbi.entlevels. Again, the EIS would have to be reopened and permits obtained from the EPA, other Federal agencies and the Trust Territory. . ., s