Research Is under way to characterize the effects of selfirradiation on radwastes which may be generated when organic ion-exchange media are used in water demineralization or decontamination operations at nuclear facilities. External factors affecting the relation between laboratory evaluations and field performance are emphasized• Initial experiments do not yet indicate substantial radiation dose-rate effects on radiolytic gas yields or acid product formation, when (fully swollen) sulfonic acid resins are irradiated in a sealed air environment. At the same time, oxygen gae is removed from the environment of irradiated resins. Interaction between mild steel coupons and acidic species produced in the irradiation Induced decomposition of sulfonic acid resin results in irradiation enhanced corrosion. Corrosion rates depend on radiation dose rate, moisture content and resin chemical loading. In some caaas, corrosion rates decrease with time, suggesting depletion of acidic species within the resin bed, or a synergistic interaction between resin and corrosion coupon. Implications of these and other results on evaluating field behavior of radwsate containing ion-exchange media are discussed.

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This report presents the analytical results for tritium content of soil cores taken at the Barnwell, South Carolina, disposal site, field measurements at Barnwell, concentrations of free chelating agents in selected trench waters, and the analyses of water samples collected at the Maxey Flats, Kentucky, disposal site. Tritium contents in soil cores taken below the trenches show a decrease in tritium with depth to a minimum value at approximately ten meters, followed by an increase below this depth. This deeper maximum probably represents the downward movement of the previous years seasonal maxima for water infiltration into the trenches. This amount of downward migration from the trench bottom is approximately what would be expected based on the hydraulic conductivity of these sediments. Field measurements of trench waters at the Barnwell, South Carolina, disposal site indicate that the waters are chemically oxidizing regimes relative to those at Maxey Flats and West Valley. Analyses were performed to determine the amounts of free chelating agents DTPA, EDTA, and NTA in selected trenches at the Maxey Flats, West Valley, Barnwell, and Sheffield, disposal sites. Amounts of free chelating agents were generally below lj.ig/g, with one samp}e as high as 28••llg/g. No drastic changes in trench water compositions were observed relative to previous sampling at Maxey Flats. The experimental interceptor trenches contain detectable amounts of strontium and plutonium. Tritium contents vary from typical disposal trench levels (E7-E8 pCi/L) in trench IT-2E, downward four oders of magnitude in trench IT-5 in a decreasing trend along the line of experimental trenches.. .

Water samples from the disposal trenches of two low-level radioactive waste burial sites were analyzed for their inorganic, organic, and radionuclide contents. Since oxidation of the trench waters can occur during their movement along the groundwater flow path,experiments were performed to measure the chemical and physical changes that occur in these waters upon oxidation. In addition to the highly acidic conditions of the oxidized Maxey Flats trench water, low concentrations of chelating agents, shown to exist in trench waters, may be responsible for keeping radionuclides in solution following oxidation of anoxic trench leachates from Maxey Flats and West Valley burial sites.