After more than two decades of works, Finland finalizes preparations to put it into operation the world’s first permanent nuclear waste repositorywith the aim of burying tons of spent radioactive fuel more than 400 meters deep for the next 100,000 years.
This pioneering deep geological repository (AGP), named «Onkalo» (cavity in Finnish), is located next to the Olkiluoto nuclear power plant, in the municipality of Eurajoki, on the west coast of Finland, and has the capacity to house the waste produced by five atomic reactors in the Nordic country over a century, about 6,500 tons.
The pharaonic «Onkalo» project cost about 1,000 million euros (US$ 1,200 million), which have been financed by the two Finnish electricity companies that produce nuclear energy (Power of Industry (TVO) y Fortum), both owners of Posivathe company responsible for the construction and management of the AGP.
As explained by Pasi Tuohimaa, communications director of Posivathe company’s objective is to start operations this year, once the latest technical tests are completed and it receives the relevant authorization from the Finnish Radiological and Nuclear Safety Agency (STUK) and the Government of Helsinki.
The safest solution
While nuclear waste from around the world is temporarily stored in pools located in the atomic plants themselves or in dry deposits on the surface, Posiva boasts of offering a pioneering, much safer solution that is a global example.
The company chose the «Onkalo» site for safety reasons, since the bedrock where it is excavated has a high impermeability, great geological stability and there is hardly any seismic activity.
«I think there is much more risk when it is temporarily stored at ground level. Of course, you could say that there is nothing that is risk-free, but these are very small,» Tuohimaa said.
«Due to the multiple barrier system, it is actually very safe. I think the eighth or ninth barrier is half a kilometer of bedrock very old and stable. But it is not the only solution, because in France they are planning to put (the spent nuclear fuel) directly in clay, so there are many other possibilities to isolate it from humans and nature,» he added.
Sealing and storage of waste
In addition to having kilometers of tunnels and galleries, «Onkalo» has a fully automated encapsulation plant to avoid the exposure of workers to the radioactivity of spent nuclear fuel rods during the waste packaging phase.
Before this phase, the uranium used will have been left to cool for about 40 years in temporary deposits, after which only one thousandth of its original radioactivity will remain, according to Posiva.
After that time, the fuel will be packaged in cast iron containers covered by a thick layer of anti-corrosion copper and placed in deposition holes. 433 meters deepwhich will then be sealed with bentonite clay.
According to the Finnish company, once deposited in its final location, this sealing system and a few meters of bedrock will be enough to completely contain the radiation released by the spent fuel.
«Onkalo» is expected to maintain its activity for the next hundred years until its storage capacity is completely completed, at which time the entire facility will be definitively sealed.
A long term investment
Although the construction of «Onkalo» began in 2004, the idea of seeking (and long-term financing) a definitive solution to the problem of radioactive waste in Finland dates back much earlier.
According to Tuohimaa, since the start of nuclear energy production in 1977, Finnish operators have paid between 30 and 40 million euros annually to a fund administered by the Government to pay for the future final storage of their nuclear waste.
«I believe that currently this fund has about 3.5 billion euros«he noted, which guarantees that nuclear companies will be responsible for financing the disposal of the fuel they have spent even if they go bankrupt.
Juha Poikola, public relations director of TWOexplained that Finland, despite having the technical knowledge and the ideal type of subsoil, does not contemplate doing business by burying nuclear waste. third countriessomething that is prohibited by law.
EFE Agency.
GML
