necessary correetions. The laboratory data from surface soil samples were used to estimate the ratio of TRU to 24! Am, which was multiplied by the corrected in situ data to get raw TRU estimates. The final step in processing data for initial surface characterization was to use the TRU data in the kriging programs to make estimates of average TRU activity. These estimates were then used to define preliminary cleanup boundaries, and to determine where to take more measurements. Data from the additional measurements were processed to the stage of raw TRU estimates, and were then used to determine refined boundaries and estimate the volume of soil to be removed. After each soil lift, the in situ remeasurement data were processed to the raw TRU data stage, and used to check against the applicable cleanup criterion. The final post-cleanup data were treated in the same manner, and were used in estimating the total TRU activity removed and for the final characterization. Data Preservation. The DRI statistician was responsible for assuring the preservation of all in situ data, including the gamma spectra. During the cleanup, the EIC lab manager was responsible for preserving the laboratory gamma spectra. After the field work ended, all spectra were transferred to DRI-Las Vegas to be prepared for long-term storage. AS soon as a set of IMP data tapes came into the data processing office from the field, the EG&G scientist checked for errors and determined any efficiency correction. The tape was then copied to magnetie disk, the errors corrected, and relevant comments from the field log sheets added to the stored spectra. From this point on, there were always at least two copies of each spectrum on magnetie media. For example, the cartridge tapes were not recycled until the data had been copied to magnetic tape in Las Vegas from a second disk copy of the data. The disks used to carry the second copy to Las Vegas were also recycled, but not until the data on magnetic tape had been verified. The data extracted from the spectra were also preserved in multiple copies. Printouts of identifying information were made both in Enewetak and at Las Vegas, and these showed the 241 4m data. The Tam data were arranged in matrices according to location and stored on cartridge tape, with a hard copy in the files. Matrices of computed TRU data and of estimates of area average TRU were also stored on cartridge tape with hard copies in the files. The cartridge tapes and magnetic disks were stored in a fireproof file to protect them. When a tropical storm or typhoon approached the atoll, the tapes, disks, files and notebooks of data and results were double-bagged and sealed in waterproof plastic and stored in the fireproof file. The program disks and tapes were also stored in the file and were similarly protected during severe storms. Once, when personnel were evacuated from the atoll because of an approaching typhoon, the tapes, disks, notebooks, etc., were also evacuated with the departing personnel. Other aspects of the preservation of programs included having copies on both disk and cartridge tape, with a documented hard copy in a programs notebook. Copies of the programs and documentation were also kept in Las Vegas. 5.3.3 Data Transmittal Typieally, formal data transmittals would be drafted by the DRI statistician, then the text and illustrations would be reviewed by the ERSP tech advisor. Necessary revisions would be made, and the document sent to the ERSP managerfor review and transmittal to JTG. Information that was ordinarily sent in formal transmittals included initial characterization estimates of TRU activity, preliminary cleanup boundaries, revised boundaries, estimates of total soil volume to be removed and of total TRU activity removed. Radiological cleanup status charts were maintained routinely, and were included in the Quarterly Operations Reports. Some Tech Notes were also included in formal transmittals when they were needed for complete understanding of the results. 150