Nuclear Waste: An Unsolvable Problem even in nuclear power pioneer Germany
Even though the nuclear crisis in Japan – which rang alarm bells around the world about the impact of radioactive decay leaking – may have led Thailand to review a plan to build a nuclear power plant, and to postpone the decision for another three years, the question of a nuclear power plant does not stop at only the issue of safety. For Thailand, the questions to consider are the costs which are high and whether investing in such technology is worthwhile, given our economic variables. Moreover, the calculation of the costs ad expenses has to embrace the whole system.
Over the past few months or so, we have found no clear answer as to the enormity of material damage as a consequence of the leakage of radioactive decay from the Fukushima Daiichi power plant. This is because both TEPCO and the Japanese Government have not yet completed their process of problem solving. The extent of damages from these nuclear leakages might be one possibility that might recur at nuclear power plants all over the world.
The problem that will surely follow after any decision to build a nuclear power plant is the elimination of the eventual nuclear waste. To this day, no country in the world has been able to eliminate permanently the waste from used nuclear rods and other radioactive decay. The Thai agencies responsible for this still have yet to find a clear answer, triggering a current of speculation that one possible option should be the use of a potash mine in the Northeast for keeping these nuclear residues.
Current practice among countries with nuclear power plants mostly calls for geologic disposal. In other words, nuclear residues are kept in hollows several hundred metres under ground to prevent leakage in future. But this method is causing rows in some countries, for instance in Germany, which is facing a dilemma from keeping nuclear waste in a salt mine due to the seeping of non-saline water into the mine, which may lead to the leakage of radioactive decay into the surrounding environment and community.
This article recounts the lessons learned from a visit to the salt mine ASSE II last year.
This mine, first built in 1906 at 750 meters below the earth surface but now abandoned, was chosen by the German Government in 1960 as a permanent storage for nuclear waste. This stemmed from the belief that salt or glutinous earth possesses properties that can prevent the spread of radioactivity. At that time, Germans had not yet seriously studied the risks and dangers of the disposal of nuclear waste.
From 1967 to 1978 residues from nuclear facilities from all over Germany were transported to the ASSE II mine. It now holds 125,000 barrels of low-level and 1,300 barrels of medium-level nuclear radioactive waste.
Ten years later, water was found to have seeped into the mine chambers. Some layers of salt were eroded, causing cracks in the salt rock which partially collapsed. The nuclear waste containers were covered by the crumbled salt rock and saline water. This was considered a very hazardous situation because the metal barrels would soon be corroded, leading to radioactive material being leaked and contaminating the earth and underground water. Left unattended the mine could collapse and release the radioactive radon gas into the atmosphere.
The Helmholtz Association, a state-sponsored scientific research organization tasked with managing the nuclear waste depository, failed to make the development public until 2008. This led to renewed discontent among residents in nearby communities who have protested against the depository since it was first proposed. As a result, the management of ASSE II was re-assigned to another state organization.
Fixing the problem proved to be a headache. The first thing the German experts had to do to prevent the mine from collapsing was to inject concrete into the cracks in the salt rock and pump out the water as well as install a ventilation system to protect operators against exposure to radon. The next step was to remove the buried waste containers, some of which were already damaged and leaking radioactive material, and contaminated salt and soil from the mine. The operation was extremely complex having to deal with radioactive material in the form of solid, liquid and gas at the depth of 750 m and required a huge amount of expense.
Reinhard Gerndt, for 40 years the core leader of opponents to the disposal of nuclear waste at ASSE II, recalled that the authorities originally issued a technical report proposing the closure of the salt mine and turned it into a permanent nuclear waste storage. But the discovery of water seeping into the mine indicated that the data in the report was inaccurate, sparking currents of opposition among the residents.
The protest made the news headlines, drawing the attention of the general public to this problem. Pressure movements grew to such an extent that the German government had to assign a new agency to take charge of the matter to placate the opposition. But villagers in nearby communities had been affected by the depreciation of their properties and the risk of radioactive decay contaminating water sources, especially if the authorities tried to extract nuclear substances by diluting the salt in the mine with water. In a worst case scenario, there might be contamination within two years. But the residents expect contamination to occur certainly within the next 30 years.
Currently the management and care of the ASSE II comes under an agency called Landesamt fur Bergbau und Geologie (LBEG) or State Office for Mining, Energy and Geology, which has been mandated by the German government to solve the problem of water seeping into the salt mine.The short-term solution to the problem is to pour concrete into the cracks in the salt rock in order to stop top layers of salt from sinking further. However, nobody knows for how long this short-term solution will be able to keep the problem at bay. The agency is studying the possibility of transporting nuclear waste out of ASSE II before they are confronted with the problem of the salt mine sinking.
Annette Paritz, an official from the radioactivity protection department under the Environment Ministry who has been working on the problem of ASSE II since 2009, said once the decision is made to move nuclear waste somewhere else, the agency will have to face the big problem of how to manage safely the existing nuclear waste.
A more acute question is to where would the waste moved because there exists not a single disposal site that can store nuclear waste safely and permanently. Even now, there is no way of speculating for how many years it will take to solve the problems of water seeping into the mine, and the removal of nuclear waste from ASSE II.
At present an estimated 80 million euros a year is needed to implement the immediate solution. However, to solve the problems in the long term by removing the entire lot of nuclear waste from ASSE II safety would require a huge budget, in terms of research, equipment, manpower, and the transportation of waste. The burden of these expenses inevitably lies on the shoulders of the German government and people.
An important lesson to learn from Germany is not only a technicalone, that is how to prevent the spread of radiation in nuclear waste disposal but how to deal with organizational problems as well.
Annette Paritz further explained that all these problems stemmed from a lack of comprehensive knowledge and understanding of the risks that might imperil the country in the future. This mine had kept the nuclear waste containers under ground for more than 30 years. The crumbled salt covering the barrels had hardened over time, making it hard to get to the barrels. This problem was compounded by the lack of knowledge on the part of the responsible authorities at the time resulting in the lack of care in stacking up the barrels so that some of them were damaged and leaked. In addition, there had been no planning for the removal of waste when problems arose. Therefore to remove the waste, all the barrels together with the contaminated salt will have to be removed.
As of now, Germany still has no clear answer on the matter of permanent storage for nuclear waste. The complicated problem at the ASSE II mine involves only low- and medium-level radioactive waste. The problem is definitely more complex for the highly radioactive spent fuels that it has accumulated generated over four decades of nuclear plant operation. Although the country has decided to abandon nuclear power completely in 11 years, the accumulating nuclear waste would remain hazardous for an indefinite period.
Some German activist groups have proposed the storing of nuclear waste above ground for the sake of transparency and to allow monitoring. But this method also carries risks and it looks as if the problem will remain a problem for the Germans to spend some time yet putting heads together to solve.
For Thailand, if a decision is made to build nuclear power plants, we may have to ask ourselves whether we already have in hand clear exits on the matter of storing nuclear waste which our children and grandchildren will have to deal with in future for hundreds or even tens of thousands of years.
More than that, are Thai people ready to bear the burden of hidden costs arising from the risks of having nuclear power plants and radioactive wastes that will follow?
If the answers to these questions are simply an attempt to pass on the problem to the countries selling uranium to Thailand, or equivocal as usual, then the postponement of a decision on the installation of nuclear power plants for three years may not be enough a time span for the future of the next generations which will have to bear the burdens.
----This article has firstly published on Green Line, no. 30: September – December 2011 by Department of Environmental Quality Promotion, Ministry of Natural Resources and Environment----