Table 3. Distribution of plutonium in size fractions and contribution of sizes to total soil plutonium in desert pavement Sample Depth Size Range (ym) (cm) Activity* 2,000-840 840-250 250-125 125-53 53-20 20-5 5-2 <2 - 2.5 A B C 2,007 94 0.8 3,017 1,077 10.0 3,945 1,365 12.6 22,295 3,634 33.6 76,271 2,700 24,9 58,338 1,633 15.1 30,099 217 2.0 13,143 104 1.0 2.5- 5.0 A B C 16 0 0 23 7 3.8 291 82 44.3 73 10 5.4 638 25 13.5 369 41 22.2 266 12 6.5 196 8 4.3 5.0- 7.5 A B C 7 0 0 3 1 2.6 33 8 21.0 38 5 13.2 15 1 2.6 78 9 23.7 72 5 13.2 172 9 23.7 7.5-10.0 A B C 7 0 0 20 6 3.6 23 7 4.2 78 11 6.6 725 26 15.5 711 83 49.4 215 9 5.4 640 26 15.5 0 *A = dpm/g in size fraction; B = contribution in dpm/g of soil, activity rounded off to nearest whole number; C = percentage contribution of activity in size fraction to soil.