Special Issue on Hazardous Nuclear Waste Disposal

Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology in research and medicine. Radioactive waste is hazardous to most forms of life and the environment, and is regulated by government agencies in order to protect human health and the environment. Safe management of nuclear waste has been accorded high priority right from the inception of the nuclear program. An integrated approach, along with adoption of appropriate technology, has been the key factor in the successful implementation of the waste management strategy. Although it is recognized that the technologies currently adopted are adequate, waste management being a sustainable development, sufficient scope exists for improving of technology to enhance process performance and meet future requirements. The special issue on Perspectives in Hazardous and Nuclear Waste Disposal—Analysis, Design and Practice highlights some contributions in this topic area.

Abdelaal and Rowe studied the antioxidant depletion response of geomembranes. They showed that increasing the pH from 9.5 to 13.5 in solutions that represent typical low-level radioactive waste leachate increased the antioxidant depletion rates detected by both standard and high-pressure oxidative induction time tests (Std-OIT and HP-OIT) and also increased the residual HP-OIT values. Arrhenius modeling is used to predict the length antioxidant depletion stage for each solution.

Snehasis Tripathy et al. studied the characterization and conducted laboratory tests on compacted MX80 bentonite and showed that the applications of thermal and thermohydraulic gradients were found to cause redistributions of water content, dry density, degree of saturation, and suction within compacted bentonites. Kao et al. showed that total petroleum hydrocarbons (TPH) fractionation analysis could be regarded as feasible for future health and risk assessment for the TPH contaminated site. This study provides a streamlined process to develop more practical and economical RBCA strategies for TPH-contaminated sites. Rakesh et al. indicate that soils containing some clay minerals (montmorillonite) have a comparatively higher distribution coefficient ($K_d$) and attain dynamic equilibrium early compared to soil with less clay content. It was also observed that $K_d$ increases with the increase in liquid to solid ratio almost linearly but steeply.

Yashir et al. studied the swelling behavior of bentonite-based backfilling materials and showed that the induced strains caused a decrease in the swelling pressures of the saturated backfilling materials. The study also shows that the swelling index of backfilling materials can be used to assess the recoverable swelling pressure following any induced strain.

Krishna Reddy et al. studied the coupled hydromechanical behavior of landfilled waste in bioreactor landfills and developed a numerical formulation that is then validated. They show that the mathematical model is capable of providing information necessary for the design of effective bioreactor landfills by incorporating coupled hydromechanical processes.

It is hoped that the research findings in the aforementioned articles are useful for nuclear waste and municipal waste disposal practice.