Common Questions

Explanations of the terms used in other pages


Biogeochemistry is the science of how chemical, biological, physical and geological processes and reactions interact to govern the natural environment.


Carbon Capture and Storage (CCS)

CCS is a technology whereby Carbon Dioxide (CO2), produced during the use of fossil fuels in electricity generation and other industrial processes, is captured and prevented from entering the atmosphere.  CCS comprises 3 stages: separating and capturing the CO2 from large industrial plants; compressing it for transportation and then injecting it at several km depth underground in carefully selected geological formations.

See also


Environmental impacts

Broadly these are impacts of a proposed project or development on the environment in terms of its effects on human health and ecosystems.  Cultural and socio/economic impacts are also considered. Formally, these are all evaluated as part of an analytical Environmental Impact Assessment by which the anticipated effects of a project on the environment can be measured and evaluated.



The disposal of waste in deep geological formations e.g spent fuel at Olkiluoto, Finland.



Geomicrobiology is the science where Biology meets Geology. It examines microbes and microbial processes to understand their role in geological processes. Examples of such processes include: element cycling, formation and degradation of minerals, development of groundwater chemistry, impacts on fluid and contaminant movement in rocks, rock weathering, soil and sediment formation.


Natural analogues

There are many definitions but the generally accepted term for natural analogue in the context of radioactive waste disposal is described as  ‘”…an occurrence of materials or processes which resemble those expected in a proposed geological waste repository (Côme & Chapman, 1986)”. More recently, Alexander et al (2015) have said that the term ‘natural analogue’ has taken on a particular meaning associated with providing supporting arguments for a repository safety assessment.


Radioactive Waste

The International Atomic Energy Agency definition of radioactive waste (IAEA, 1994) is ‘Any material that contains or is contaminated by radionuclides at concentrations or radioactivity levels greater than the exempted quantities established by the competent authorities, and or which no use is foreseen.’   Radioactive materials can be used for many purposes such as generating power, treating medical conditions and for research purposes. All of these generate waste and, if contaminated or activated by radioactivity above certain defined levels, are categorised as radioactive waste. Waste is broadly categorised as low, medium and high level according to its level of radioactivity.

The IAEA provides a detailed explanation at