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The thermoluminescent characteristics of 15 soil and 73 mineral and rock samples were examined. The soils of widely different chemical types showed wide range of thermoluminescent characteristics. Generally, soils high in lime content showed very high TL. One soil, which was relatively high in free iron content exhibited no TL. The natural TL of soils appeared to be affected by the kinds and amounts of mineral and rock materials present. Since the TL of the different samples even of the same mineral species varied widely, there appeared to be no criterion by which minerals could be identified or classified on the basis of their natural TL. Different lots of samples, however, might be differentiated from each other. Most soils and minerals showed only little, if any, TL below 200°C.

Water and ammonium acetate extractable Zn, Mn, Cu, Cr, Co, and Fe in four different soils were examined. The soils were heated at various temperatures (100°, 200°, 300°, 400°, 500°, 800°, and 1,000°C). The extractability of these elements did not show any consistent trend among the soils examined, but soil heating did change their extractability.

The effect of organic (fulvic and humic acids) and inorganic fractions of soil on the sorption and exractability of 239Pu(IV) as a function of pH was determined by using an equilibrium batch technique. The results indicated that Pu(IV) is strongly sorbed on the inorganic fraction of the soil under soil pH condtionsnormally encountered in natural environments. Plutonium appeared to form stable complexes or chelates with fulvic and humic acids in the pH range studied (1.3 to 11.7). In mixtures of pure fulvic or humic acids with soil inorganic fractions, the extractability of Pu was substantially influenced by organic-inorganic interaction. The influence of the inorganic fractions was more evident in the lower pH ranges, whereas that of the inorganic materials was most evident in the higher pH ranges, generally above pH 6. Some implications of the results on plutonium movements in solids were discussed.

Using an equilibrium batch technique, we determined the effect of clay minerals on the extractability of 239Pu(IV). The <2 μm size fractions of three American Petroleum Institute reference clay minerals (montmorillonite No. 26, Kaolinite No. 3, and illite No. 35) were used. The extractability of Pu from clay suspensions prepared on an equal weight basis differed to some extent from those prepared on an equal equivalency basis. The Pu extractability also depended on clay-solution ratio, clay mineral type, clay particle size distribution, NO3−concentration, and pH.

Laboratory experiments were conducted to determine the effect of induced aggregation of soil materials on the chemical extractability of Sr90 and Pm147 contaminants in the soil. Four different binding agents (Portland cement, ferrous sulfate, sodium silicate, and polyester coating resin) were used to induce soil aggregation. In general, each binding agent increased the water-extractable fraction of Sr90, while it decreased the NH4OAc-extractable fraction. The increase of the water-extractable fraction was due to exchange displacement during the interaction of the soil particulates and the binding agent. The decrease of the NH4OAc-extractable fraction was considered to be due to the blocking action resulting from the interaction of soil particulates and the binding agent. The extractability of Pm147 differed from Sr90 in that the NH4OAc-extractable fraction was increased by FeSO4and the water-extractable fraction was decreased by the resin treatment. Several reasons for these effects are given.

The distribution of different forms of N in desert soils collected at Nevada Test Site were examined. Soil profiles were sampled in 7.6-cm increments to various depths of which the maximum was 91.4 cm. Among the soil profiles examined, the different forms of N in the surface layer (0.0–7.6 cm) was always NO2-N (not detectable) < extract-able NH4,-N < NO3-N < fixed NH4+-N < organic N. In the sublayers, some variations from this order of N forms occurred in that the extractable NH4-N was greater than NO3-N with the presence of trace amount of NO2-N and/or the fixed NH4-N was greater than organic N. The amount of total N was the greatest in the surface layer and usually decreased very sharply in the second layer (7.6–15.2 cm). Below the second layer, the total-N contents generally varied slightly. In the surface layers, the total N was always accounted for primarily by organic N. Depending on the soil and the profile layer, the concentration of the total extractable inorganic N ranged from 0.00004 to 0.00586 percent by weight of oven-dry soil. Expressed as percentage of total N, the range was 0.33 to 16.17. The amount of fixed NH4+-N varied somewhat with different soils, but within any given soil profile, it generally varied slightly. The fixed NH4-N in the profiles collected in different areas and under different plant species ranged from 0.0028 to 0.0079 percent by weight. Expressed as percentage of total N, the range was 3.4 to 74.4. The exchangeable K concentration under the plant was 41 to 240 percent greater than in the bare soil. The higher exchangeable K plus the higher organic matter content was considered to cause the lower NH4-N fixation under the plant compared to its fixation in the bare soil.