OFFICLAL USE ONL Safety. Mr. Catlin pointed out that EPA took over the Federal Radiation Council's function and they are charged with providing guidance with respect to radiation problems, The mechanism for discussions between agencies which was provided by the FRC no longer exists. As an interim procedure the AEC may mecessarily have to set some of its own guidelines since the reorganization setting up EPA has caused a serious delay in providing this information. Dr. Stout asked about the problem of determining degree of exposure to plutonium and asked whether there might be exposures that we simply don't know about. Mr. Catlin thought there might be such exposures but that it would be relatively unlikely. Detection methods are not sensitive enough to detect very low levels of exposure. He pointed out that if plutonium facilities are not controlled by the AEC and if they continue to proliferate, the problem of plutonium exposure could become acute. Dr. Stout asked where the necessary instrumentation for detection of low levels would come from. Dr. Totter felt that the Division of Biology and Medicine's instrument development program would probably be able to meet the requirement. Mr. Facer, from the Division of Military Application, discussed the problem of plutonium contamination of soil. Among the areas where such contamination has occurred are Palomares in Spain, Thule, Greenland, the Nevada Test Site, the test sites in the Pacific, and the Rocky Flats operation in Colorado. Accidents, weapons tests, etc., have all contributed to spreading plutonium around. Mr. Facer felt strongly that the criteria for cleaning up an area are far too conservative in view of the biomedical evidence concerning the likelihood of a significant exposure from resuspension of plutonium from the soil or through movement up the ecosystem. In Spain they removed 5500 drums of soil where the contamination was relatively high and deep-ploughed a square mile area where any level of plutonium was detectable. Dr. Bair then introduced the biomedical portion of the briefing. The first speaker was Dr. Engelmann, who described current studies on the resuspension of radioactive materials from the ground surface. Various contractors have undertaken systematic studies of the factors involved in resuspension. Earlier attempts to estimate a single constant which represented a resuspension factor’ proved not to be very helpful. One current approach that is being used is the direct one of "salting'’ an area with a contaminant and making direct measurements of how it moves down wind. These studies are being conducted at Rocky Flats. Dr. Engelmann pointed out that plutonium may quickly gets attached to larger particles which puts many of the particles beyond the respirable range. At present, they estimate that 20-40% of the plutonium contamination at Rocky Flats is in the respirable range. Dr. Engelmann closed by outlining additional ongoing and proposed research being monitored by his branch of DBM. | Mr. Jared Davis, former ly of the DBM staff, and now with the Nevada Operations Office, described the studies on plutonium contamination by alpha OFFICIAL USE ONLY