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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The growth of color centers during irradiation, and the decay after irradiation, has been studied in two glasses using recently developed equipment for making optical absorption and luminescence measurements during and after electron irradiation. The glasses studied were NBS 710, a soda-lime silicate glass and NBS 711, a lead silicate glass. Both glasses exhibit similar coloring characteristics. The radiation induced absorption spectra consists of a weak gaussian shaped band in the visible, a stronger gaussian band in the ultra violet and a band edge "shift" which may be accurately approximated by a third gaussian band. For all absorption bands the color center v.s. dose (or irradiation time) curves can be accurately resolved into two saturating exponential and one linear component. The decay curves obtained after the irradiation is terminated can be accurately expressed by three exponential components. Coloring and decay curves made at different dose rates indicate that the processes responsible for decay after irradiation and electron hole recombination during irradiation play important roles in determining the rate and extent of coloring. The results are qualitatively in agreement with some very simple kinetic treatments for color center formation. In some, but not all, respects the quantitative agreement is also good. Lastly, the results appear to provide strong evidence to conclude that it is necessary to make measurements during irradiation to establish Che formation kinetics of color centers that are unstable at the bombardment temperature.

This report covers the activities of a small group at Brookhaven National Laboratory (BNL) studying radiation damage in.natura1 rock salt, synthetic NaCl crystals, granite, basalt and other minerals of interest for radioactive waste disposal applications. The people involved are: