As an indication of the capability of this procedure to produce an alpha spectrometrically acceptable plate, the spectrum in Fig. 2 is presented as typical. This spectrum is one from an actual NAEG vegetation sample supplied to LASL-H7 by LFE. relative positions of 238 U, 235 U, 234 The figure shows the U, and the added 232 U. Typical U recoveries found to date on this type of vegetation sample range from 72-100%. The actual sample represented in the figure contained 239-240 239-240 . . 300 d/m Pu; the amount of Pu found in the U fraction was 0.16 d/m. This calculates to a .05% carry-over of 239-2405... There are several problems yet to be worked out. For instance, this procedure with the current alpha spectrometer cannot quantitatively distinguish between 2354 and 2361 If there is any 2365 to be found U to 236 in NAEG samples, the ratio of U must first be determined by mass spectrometric techniques. The ratio can then be applied to the 235-236 U result from alpha spectrometric measurements to quantify the 239, A second problem noted is that the plates are not as consistently clean as with the Pu procedure now in use. This is due to small amounts of Ni, Cu, Zn, and Fe present in the column eluate which seem quite difficult to remove prior to electrodeposition. However, of the nearly 100 plates thus far prepared only, 5 were unacceptable. It should be noted that the alpha spectrum presented in Fig. 2 represents only one resin column cleanup of the sample. It is believed that the problem of metal interferences can be adequately handled by a second column separation of U, and this feature is incorporated into the tentative procedure. Laboratory Cross-Calibration As part of the continuing effort to cross-calibrate the various NAEGassociated laboratories, LASL-H7 circulated a low-level Pu source for alpha spectrometry. Each laboratory was asked to report the amount of 2385, > 239-2405, | and 2425. they found on the plate. To date, the source has been assayed by three LASL laboratories and three of the five NAEG-associated laboratories. The results (Table 1) show a good agreement for 2425. but both 239-2405, and 2385. undergo substantial variation. For the purposes of NAEG soil analysis where there is an 20