Table 8. Comparison of radiochemical results from separate samples of a largevolume soil specimen. (Ratios are A to B sample aliquot) .4 Master log number 240 40: 23984 241 : 23904 239 5K 2394240, atom ratio atom ratio dpm/g dpm/g 243 Pu dpm/g 241 90 Am dpm/g Sr dpm/g Bikini soil O01-0065-01 1.01 40.4% 1.21 42.1% 1.02 +0.8% 1.02 20.6% 1.23 42.2% 01-0088-9] 1.01 40.9 0.86049.3 1.03 40.9 1.03 40.8 0.88329.4 0.90928.6 0.98742.1 0.968t1.1% 0.99041.7 01-0111-01 0.998+0.6 1.09 42.8 1.00 +1.6 1.00 41.3 1.10 £4.4 O1-0134-32 0.98542.5 0.90 +15 0.92744.3 0.920£3.3 0.84546.5 - 01-0157-32 1.01 40.3 1.03 40.9 1,00 40.5 1.01 40.4 1.03 41.2 —_—— 1.00 40.7 O1-0180-32 0.99741.1 0.93044.8 1.00 40.8 0.99840.9 0.93044.9 —_— 9.99842.4 O01-0226-32 1.01 £0.4 1.01 40.8 0.99540.5 0.99940.4 1.01 +1.0 _ 01-0318-95 0,992#2.2 01-0343-90 0.99840.8 0.955+1.3 1.04 +2.2 1.04 41.9 0.99342.6 O1-0387-95 0.9844#2.2 0.99 +28 1.06 3.6 1.05 +2.4 1.1 O1-0525-71 1,01 40.8 1.16 47.4 0.95641.3 0.95941.0 O1-0548-72 0.984+3.5 1.07 46.1 1.06 44.2 01-0617-92 1.01 41.2 1.06 44,4 1,03 40.9 1.04 +0,.9 1.09 +4.5 1.0041.1% 1.0411% 1,01£4.0% 1.0144.0% 1.0411% 06-0709-32 0.99441.1%2 0.91 411% 1.01 40.9% ' Average 1.03 +4.0 0.95044.5 1.03 £2.4 0.985£2.0 0.970£3.3 0.96522.7 1.04 40.8 1.08 46.4 0.96542.6 428 0.95110.9 1.11 £7.5 —_——— 1.03 $2.6 — 1.02 43.4 0.99248.6% 0.99743.22 Eneu soil 1.01 40.9% 0.92 111% _olcl 1.01 41.9% 06-0755-32 0.978+3.8 1.05 +2.4 1.04 #2.6 _— 1.08 +6.5 06-0893-92 1.02 +1.5 ——- 0.96141.4 0.97141.3 —_—— _ 0.98846 .3 Average 0.99742.1% ——— 1.0144.4% 1.0143.4% —_—- —_—_ 1.0344.7% * All results are reported to a reference time of 1 January 1975 (001.00 2, 75). 7241 signal or calculation of a detection limit. Wet-chemistry measurements served two purposes: Am concentration more accurately. Uncertainties in self-absorption to permit corrections because of voids resulting comparison of two different methods 41an, for measuring and for other can limit the accuracy of 241oy samples, assessment via gamma spectrometry. from settling of the soil in the to provide greater sensitivity for detecting ereo than available Thus, from routine gamma measurement. 41 Am data for soil samples reported via gamma Comparison data for 52 soil samples are presented in Table 9. it appears that the The mean spectrometry may be systematically low by about 20 percent. Even so, value for the MCL:LLL ratio is. the effect of -a 20 percent bias will 1.2 + 164, with evidence for signifi- be negligible on the estimated exter- cant bias. nal dose since For soil samples, wet very small fraction to the total. chemistry is expected to assess the ~16- a] J010098 Lam contributed a