C around the world are researching, developing and demonstrating disposal of long-lived radioactive waste in engineered repositories located in suitable deep underground geological formations as the reference solution to protect present and future generations and the environment. In some countries, actual implementation of geological disposal projects is only a few years away. Countries are als...

This paper aims at describing numerical methods developed within the Melodie code to perform 3D saturated flow and transport calculations in the framework of radioactive waste geological repository. The diffusive type terms are discretised by a standard finite-element method and the convective term is treated with a Godunov-type finite-volume approach. The simulation domain is meshed using a st...

Low carbon steel has been considered a suitable material for component of the multi-barrier system employed on the geological disposal of high-level radioactive waste (HLW). A non negligible amount of dihydrogen (H2) is expected to be produced over the years within the geological repository due to the anoxic corrosion of metallic materials and also to the water radiolysis. The influence of the ...

Some of the low level radioactive wastes from reprocessing of spent nuclear fuels contain nitrates. Nitrates can be present in the form of soluble salts and can be reduced by various reactions. Among them, reduction by metal compounds and microorganisms seems to be important in the underground repository. Reduction by microorganism is more important in near field area than inside the repository...

Countries around the world are researching, developing and demonstrating disposal of long-lived radioactive waste in engineered repositories located in suitable deep underground geological formations as the reference solution to protect present and future generations and the environment. In some countries, actual implementation of geological disposal projects is only a few years away. Countries...

Any activity involving radioactive materials, in industry, research, medical applications, and most notably nuclear power production, produces radioactive waste. The high level (life threatening doses of radiation) and long lived (radiation levels remaining intact up to 100.000 and even millions of years) wastes mainly from nuclear power plants, are thought to be too dangerous to keep forever w...

Bentonite is a preferred buffer and backfill material for deep geological disposal of high-level nuclear waste (HLW). Bentonite does not retain anions by virtue of its negatively charged basal surface. Imparting anion retention ability to bentonite is important to enable the expansive clay to retain long-lived (129)I (iodine-129; half-life = 16 million years) species that may escape from the HL...

The behaviour of the deep geological repository planned by SKB will depend on the climatic evolution over a long term, such as the advance and retreat of ice sheets after glaciation and deglaciation periods. The melt water enriched in oxygen due to a deglaciation episode will infiltrate into the geological media and may compromise the reducing conditions of the repository. It has been establish...