By splitting the atom we are able to release a tremendous amount of energy. In the uncertain times of the Second World War, this power was first developed to make bombs. However, as the world slowly settled after the horrors of the Hiroshima and Nagasaki bombings, other uses for this power were explored. One of them was to meet our growing needs for electricity.
Thus nuclear energy rose to the occasion in the 1950s, providing mankind with seemingly unlimited energy. However, it soon became apparent that what was thought to be the grand solution to our energy problem, in fact created another one: a highly radioactive bi-product that still to this day is the most hazardous environmental waste known to man.
Today there are two general kinds of nuclear waste: the low- and intermediate-level waste (LLW/ILW) and the high-level waste (HLW), such as spent nuclear fuel. The waste is graded according to its level of radioactivity. MKG (The Swedish NGO Office for Nuclear Waste Review) primarily reviews the process of finding the best possible final repository for the spent nuclear fuel.
To come in contact with spent nuclear fuel will lead to an almost instant death. And although the deadly radiation diminishes over time, the nuclear waste will remain hazardous for hundreds of thousands of years. This is indeed a very long a time to imagine, but in order to fully understand what must be asked of a final repository for this waste-product of our time, grasping the magnitude of the time frame is essential.
Several hundreds of thousands of years is a very long time. This means that almost everything that could potentially compromise the safety of the final repository is likely to happen. These threats include anything from the canisters starting to leak its radioactive content into its surroundings, to a man made breech; intentional or otherwise. For instance, plutonium in the spent nuclear fuel can be converted into devastating weapons of mass destruction, making it highly sought after by those wanting to do harm. However, this immense time frame also means that the final repository has to be able to withstand the enormous geological strains of repeated ice ages. As the ground buckles under the massive ice, earthquakes, rock and stress movement as well as permafrost will pose a significant threat to any repository. In Sweden, we run the risk of experiencing up to three ice ages in the next 100 000 years alone.
These are all aspects that we have to consider when deciding on a final resting place for our spent nuclear fuel, and needless to say: the decision has to be right. There is no going back; no second chances. Therefore we must not haste into a decision that will place a radioactive burden on our future generations due to a flawed method of choice, but carefully evaluate our options in an unbiased and critical manner.
When thinking of radioactive waste, what usually comes to mind might be the aforementioned spent nuclear fuel. This is most reasonable as this particular type of radioactive waste is the most harmful kind to us humans and to the environment. However, as previously mentioned there are other kinds of nuclear waste that also needs attending to; the low- and intermediate-level waste.
Low-level waste, or LLW, is mostly produced by hospitals and industry, and mainly consists of discarded rags, clothes, tools and filters. Generally, this type of waste requires no particular shielding and needs only to be stored for about 40 years.
Intermediate-level waste, or ILW, is mainly produced by the nuclear power industry’s day-to-day operation. It requires shielding to prevent its hazardous radioactivity from affecting us and the environment. It also needs to be stored for at least 500 years.
Today, the low- and intermediate-level waste is being stored in an underground rock shelter at a depth of 50 meters. The storage is located in Forsmark and it is the intention of the power industry’s nuclear waste company SKB to expand this storage in order to accommodate future demands.