This opticn does not specify action against radioactivity in soil of the islands such as ALICE, BELLE, and CLARA, nor does it recommend that residences be built on JANET. By implication, therefore, resettlement of JANET would have to wait for radioactive decay and weathering processes to reduce contamination levels to acceptable values on these islands. Since the predominant isotopes, 1370, and 9065, each have half-lives of thirty years, the waiting period could ‘s aeAé be slightly more than one. generation for each factor of two reduction in dose. On the other hand the reduction could proceed at a somewhat faster rate. marrow On JANET, reducing the maximum annual child's bone/dose from 0.72 rem/yr (Table 4, Case D-I) to the guide level of 0.25 rem/yr through natural decay of the 90 about Sr would theoretically require a wait of/50 years considering only radiological decay. It is not expected that such a reduction will actually take that long. Option IV a. All of Option III a, c, d, e, and f, plus: b. Return to JANET and build residences and community center in locations shown on the Master Plan. c. Remove a minimum of 30 cm of soil in all areas where pandanus and breadfruit are to be grown on JANET; import clean soil in which to establish these plants; or import pandanus and breadfruit from the southern islands. If these actions proved to be as effective as the theoretical predictions, this would permit return of the Enjebi people to their island. It should be emphasized, however, thateven with the above actions, predicted doses are af nr ped spear or sliphedlyabove the criteria for annual exposures and also above the . Penasal 30 year criteria. fr A e The levels are expected to be well above those of Option III. 021