The Promise of Underground Geological Repositories
The Grimsel underground rock laboratory in the Swiss Alps. (Credit: Comet). More photos...
Each year the world´s 441 nuclear power reactors create enough spent fuel to fill a football field to a depth of 1,5 metres. That´s about 10 500 tonnes of heavy metal. This waste is thermally hot and can stay radioactive for thousands of years. Because it is solid and does not readily dissolve in water, the fuel wastes are typically stored in water pools on site at the nuclear reactors for many years.
But permanent disposal places are needed. Scientists warn that the ongoing storage of spent fuel is not sustainable for the long years needed for the waste to decay and lose its radioactivity. Right now only one permanent disposal facility exists – in New Mexico where long-lived radioactive waste from United States military programmes is carefully packaged and cocooned in tunnels deep underground, in what is called a geological repository.
Containing the Heavy Metal
Global scientific consensus is that disposal in these deep underground repositories is the best and safest option available to permanently separate this waste from humans and the environment. This consensus is backed by several decades of research and outlined in a position paper by international experts that the IAEA published on The Long Term Storage of Radioactive Waste Safety and Sustainability [pdf].
Over the last thirty years many IAEA Member States have developed the methodologies for the disposal of radioactive wastes in underground "geological" repositories. Underground Research Laboratories have been set up and used for this purpose.
|
Total Stored Spent Fuel |
|
| Region | Amount (Tonnes of Heavy Metal) |
| West Europe | 36 100 |
| East Europe | 27 700 |
| America | 83 300 |
| Asia & Africa | 23 900 |
| World | 171 000 |
In 2002 a group of Member States offered the use of their underground rock labs and some associated surface facilities to help build confidence and capacity throughout the world in geological disposal of radioactive wastes.
This group, collectively known as the IAEA Network of Centres of Excellence (COE) in Training and Demonstrations of Waste Disposal Technologies, includes the following:
- Canada with the Underground Research Laboratory of Lac-du-Bonnet, Manitoba;
- Belgium with the Underground Laboratory in Mol, operated by EURIDICE;
- Switzerland with the Grimsel Test Site;
- Sweden with the Aspo Underground Research Laboratory, and the University of Kalmar;
- Wales, United Kingdom, with the Geo-Environmental Research Centre in Cardiff; and
- United States of America, with the WIPP facility near Carlsbad, New Mexico, the Yucca Mountain Project in Nevada, and Lawrence Berkeley National laboratory in California.
The in-situ laboratories in this network also provide the opportunity for hands-on training in waste disposal technologies for countries which do not have their own underground research facilities.
Spent Fuel - Global Overview, 2003
Spent fuel and high level waste makes up about 3% of the world´s total nuclear waste but contains 95% of all the radioactivity.
Global spent fuel storage capacity is about 244 000 t HM (tonnes of heavy metal). This capacity will be filled by 2017 if no new facilities are built by that time.
Trends show that a storage shortage is not expected globally; however on a national level a shortage may occur – particular in some Eastern European countries.
The first national geological repositories for permanent spent fuel disposal are expected to be in operation around 2010.
Source: IAEA Overview of Global Spent Fuel Storage
In a first of a series of in-depth profiles of waste disposal activities of this network of countries, the following article looks at the Grimsel Test Site in Switzerland.
