6.10 YVONNE FIG/QUINCE EXCISION (by Bert Friesen, H&N) 6.10.1 Introduction Radiological surveys of Yvonne in 197] and 1972 revealed several areas with levels of radioactivity sufficiently high to generate concern among participating health physicists. In May, 1972, radioactive particles retrieved from the vicinity of the Quince and Fig ground zero were analyzed and determined to have relatively high concentrations of 39py, This was a unique situation, which is further detailed in the Enewetak Fact Book. AEC officials were concerned that if milligram-sized particles could readily be found, there was a strong likelihood they might be picked up in shoesoles, tire treads, etc., and could lead to significant contamination of other areas and islands. On the basis of a recommendation by the AEC, the Air Force, having administrative control at the time, imposed a quarantine on the island. The quarantine restricted access to the island but permitted legitimate work visits under appropriate controls, The high levels of radioactivity in the Fig/Quince area continued to be of concern until a clean layer of soil was applied to the area as the last step of the cleanup described in following sections. (The Quince test was conducted before the Fig test, so normal references to the series would be Quinee/Fig, but Fig/Quince seems easier to say and became commonusage.) 6.10.2 Pre-Excision Characterization The DNA philosophy regarding cleanup priorities, discussed in Section 2.2.5, assigned a high priority to Yvonne. The DOE position held that Yvonne would likely remain quarantined and that the limited eleanup assets should be expended to produce the long-term result most beneficial to the people of Enewetak, such as cleaning Janet to a degree commensurate with habitation guidelines. The DOE and DNA agreed to participate in a conference, held 4-5 October 1977, to discuss the radiological characterization of Yvonne. The conference was an attempt to determine the level of effort required to obtain information upon which to base estimates of the volume of soil likely to exceed cleanup criteria. Specific tasks were identified and a plan of action set forth, calling for completion of the data-gathering effort by 15 January 1978. Soil samples were collected by the FRST, from both surface and subsurface locations, and processed in the ERSP Laboratory. Although the ERSP cooperated in this effort, the ERSP staff never believed the data gathered were sufficient to adequately define subsurface pockets of elevated TRU activity. On 27 January 1978, the JTG requested that effort be expended to obtain data on surface soil contamination in the Fig/Quince and Cactus Crater areas on northern Yvonne because of the need to construct facilities in or near those areas, DOE responded on 31 January that no data were being developed for Yvonne and suggested a planning meeting to determine the kind and amount of effort needed to meet the JTG request. No formal meeting was held, but after several informal discussions, DOE received a letter on 15 February requesting an in situ survey of the Fig/Quince and Cactus Crater areas so that Army construction teams could avoid areas where the transuranic levels on the surface exceeded 400 pCi/g. The survey was conducted and results transmitted to JTG on 2 March 1978. The data obtained were used as guidance for the location of roadways through the Fig/Quince area and for the location of facilities at the Cactus Crater (Figure 6-25) work site. No additional effort was expended on characterization until later in 1978. A meeting to discuss the cleanup of Yvonne was held 17 October 1978. Element representatives reviewed the status of debris cleanup and previous characterization efforts. DOE reiterated its judgement that additional in situ surveys were needed and many more surface and subsurface soil samples would haveto be collected and analyzed before any reliable excision volume estimates could be constructed. One valuable task assigned as a result of this meeting was to correlate the FRST data collected earlier with the standard grid that had evolved. Even though the earlier results were in terms of grc-~ alpha only, the data did signal the presence or absence of transuranics. Interest in the radiological characterization of Yvonne next surfaced in a letter to ERSP from JTG dated 9 December 1978. The letter requested submittal of a plan for a characterization update to include type of measurements to be taken and method of sampling, time factors for individual tasks and total time to radiologically characterize the island, number of stakes to be surveyed and placed by area, estimated depth of excision to meet Conditions A and D, and an estimate of support required. DOE responded on 15 December with all the requested information, except for estimated 194