Sign In
Information about science based innovations, solid facts to support decision-making, performance and business development for VTT’s partners, customers and anyone interested in high technology and its applications.
A magazine on science, technology and business

Posiva

​​​​​

Posiva is a pioneer in nuclear waste management

Leena Koskenlaakso | 8.12.2016

​The world’s first final disposal 
repository for nuclear fuel will begin operating in Eurajoki in the early 2020s, as planned. Posiva has provided the basis for the 
final disposal project, through 
extensive and thorough research.

At the beginning of the next decade, the world’s first final repository for spent nuclear fuel will begin opera­ting close to the Olkiluoto nuclear power plant on the west coast of Finland. The final disposal of spent nuclear fuel from the power companies Teollisuuden Voima and Fortum will take place in massive, copper-cast iron disposal canisters around 400 metres deep in the bedrock at Olkiluoto. 

 
– The intention is to continue operations at the repository for 100 years. After then, all underground openings will be backfilled and the above-ground facilities will be dismantled and landscaped.  No supervision measures are required for this passive solution, says Tiina Jalonen, Senior Vice President, Development, at Posiva.

 
– There is huge international interest in us.

 
Posiva_7.jpg

 

Hazardous materials will remain underground

Final disposal will be based on multiple barriers, ensuring that no spent radioactive fuel contaminates the natural environment or comes within reach of people. 

 
The bedrock will serve as a natural barrier. This will be complemented by man-made, engineered barriers. These will include copper-cast iron disposal canisters in which the fuel elements will be placed; a buffer of bentonite clay surrounding the canisters in the deposition holes, in order to hinder water flow and protect the canisters from damage; filling the tunnels with clay containing backfill material; and plugging the tunnel’s mouth. 

 
– Various models have shown that, even if one or more of the barriers fails, no harmful substances will reach the ground surface, says Johanna Hansen, Project Coordinator. 

 
Posiva_5.jpg

 

Construction progressing in phases

The safety of final disposal has been ensured by thorough planning and multi-year research projects in which VTT has participated. 

 
– Testing is now underway in the ONKALO underground research facility. The construction of ONKALO has enabled us to study the bedrock at Olkiluoto and the construction methods 
developed. We have recently been testing the final disposal procedures. ONKALO research 
facility will be completed during this year, and later it will be a part of the repository, says Jalonen.

 
Construction of the repository will begin as soon as ONKALO is ready. The ventilation and hoist equipment are already being built. They will serve ONKALO in the initial stage, as well as the repository later on.

 
Construction work has also begun on the foundations of the encapsulation facility. In the encapsulation facility, the spent nuclear fuel will be dried and placed in canisters, which will be closed, welded, inspected and sent to the final disposal repository or interim storage. 

 
– Passages have already been built to the underground storage facilities. We will begin building the central tunnels during the next phase and the actual final disposal tunnels in a few years’ time. The first underground final disposal areas are now under planning, Hansen says. 

 

R&D programmes providing further details

– In our current R&D programmes, we are exploring additional issues related to the safety of final disposal; the Finnish Radiation and Nuclear Safety Authority STUK required Posiva to resolve such issues when granting it a construction license in November 2015, says Jalonen. 

 
The programmes involve studying the final disposal canisters and spent fuel, the buffers, the backfilling and plugging of the tunnels, the repository site and preparations for production. In addition to fulfilling the requirements set by STUK, the goal is to obtain additional information for the design and construction of the encapsulation and final disposal facility. 

 
– This is important work. Posiva’s employees feel that it is great to be part of this project. We are highly motivated by the idea of solving the global nuclear waste challenge, says Jalonen. 

 

Setting their sights on a permit

Further information is also needed for a so-called safety case, which Posiva must complete in order to apply for a operating license for the final disposal site. Posiva intends to submit the safety case in 2020. 

 
A great deal of planning and testing is required in order to obtain the license. Posiva must also demonstrate that final disposal will work as assumed. 

 
– The planning phase of a full-scale system test is now under way. We will perform a final disposal test in demo facilities and deposition holes at ONKALO, where we will use prototype machines intended for installing the engineered barriers as well as existing, actual barrier components. Of course, we will not yet be using spent fuel in the canisters, says development engineer Pasi Rantamäki.

 
VTT is acting as the main consultant in the design of the system tests. 

VTT involved in technical development work

– VTT has long played a key role in our R&D work. We have been using VTT’s expertise in areas such as canister design, the thermal dimensioning of the repository, cement and clay materials development, and the development, testing and modelling of the bentonite clay buffer. This will enable us to evaluate the long-term behaviour of the final disposal system. VTT is also playing a major role in the development of the inspection techniques for the canisters, says Jalonen. 

 
– Our multi-disciplinary final disposal project is being supported by VTT’s many areas of expertise. In certain sub-areas, VTT experts have often been able to introduce a new and innovative method from a completely different field, says Hansen.  

 
Jalonen points out that the scientific community behind VTT has brought credibility to its work.  

 
– The building and maintenance of trust are very important in our field, she points out.

 
The Posiva personnel are highly satisfied with VTT’s systematic practices and prompt reports. They also praise VTT for recruiting skilled staff in place of retiring experts. 

 
Jalonen explains that Posiva no longer does its own basic research, but sources it externally when necessary. 

 
Posiva_13.jpg
 

Successful research cooperation

The closure of the repository was studied as part of the joint European DOPAS project, which will end in August. Under the POPLU sub-
projects, VTT participated in a full-scale plugging demonstration carried out in ONKALO. 

 
Edgar Bohner, the manager of VTT’s Infrastructure Health Team, led the instrumentation and monitoring team, which performed the instrumentation for the POPLU test plug and developed the pressure testing and water leakage monitoring equipment. Our collaboration went well, and we achieved excellent results, says Programme Manager Petri Koho of Posiva, who is serving as Project Manager for POPLU. 

 
– Our team is supporting Posiva in identifying the best and safe final disposal solutions. We develop materials and our specialism lies in the development of low pH concrete, Bohner says.

 
Bohner’s team mates are designing barriers and are investigating the industrial manufacture of buffer blocks from bentonite clay. Among other innovations, they are developing wireless sensors that send monitoring signals from the final disposal repository to the outside world. The team recently received an order for the design of test arrangements for full-scale system testing to be performed in ONKALO. 

 
Posiva and VTT have been collaborating for around twenty years. Antti Poteri, a Principal Scientist at VTT, already performed research for Posiva’s predecessor, the nuclear waste agency of TVO. His special area is modelling. 

 
– My research focuses on the migration of radionuclides through the bedrock. Our modelling calculations were used as a part of the safety case that was prepared in support of the Posiva’s construction license application.   Posiva is now getting prepared to submit its application for an operating license of the final repository and the research focus has moved to drawing up a new safety case, Poteri says. 


 
Posiva

  • An expert organisation established in 1995.
  • In charge on behalf of its owners of the final disposal of spent nuclear fuel and other expert tasks related to nuclear waste management.
  • Owners: Teollisuuden Voima (TVO) 60%, Fortum Power and Heat 40%.
  • Personnel: around 80 persons + some 200 subcontractors and consultants. 
  • Turnover 2015: around EUR 63 million.
  • Its service business subsidiary, Posiva Solutions, was founded in 2016.

 

 

VTT Impulsehttps://www.vttresearch.com/ImpulseVTT Impulse
Bioeconomy and circular economyhttps://www.vttresearch.com/Impulse/Pages/Bioeconomy-and-circular-economy.aspxBioeconomy and circular economy
Low carbon energyhttps://www.vttresearch.com/Impulse/Pages/Low-carbon-energy.aspxLow carbon energy
Designers needed in printed technologyhttps://www.vttresearch.com/Impulse/Pages/Designers-needed-in-printed-technology.aspxDesigners needed in printed technology
Impulse 2/2015https://www.vttresearch.com/Impulse/Pages/Impulse-2-2015.aspxImpulse 2/2015
All sights on generationhttps://www.vttresearch.com/Impulse/Pages/All-sights-on-generation.aspxAll sights on generation
A machine is more humanehttps://www.vttresearch.com/Impulse/Pages/A-machine-is-more-humane.aspxA machine is more humane
Renewing industrial practices creates a new competitive edgehttps://www.vttresearch.com/Impulse/Pages/Renewing-industrial-practices-creates-a-new-competitive-edge.aspxRenewing industrial practices creates a new competitive edge
Robotics – technology with multi-faceted potentialhttps://www.vttresearch.com/Impulse/Pages/Robotics-technology-with-multi-faceted-potential.aspxRobotics – technology with multi-faceted potential
Senior Scientist Jukka Hemila, VTT: From technology hype to customer understandinghttps://www.vttresearch.com/Impulse/Pages/Senior-Scientist-Jukka-Hemila-VTT-From-technology-hype-to-customer-understanding.aspxSenior Scientist Jukka Hemila, VTT: From technology hype to customer understanding
Business developmenthttps://www.vttresearch.com/Impulse/Pages/Business-development.aspxBusiness development
Traceable data will accelerate the circulation of materialshttps://www.vttresearch.com/Impulse/Pages/Traceable-data-will-accelerate-the-circulation-of-materials.aspxTraceable data will accelerate the circulation of materials
Maintenance support for astronautshttps://www.vttresearch.com/Impulse/Pages/Maintenance-support-for-astronauts.aspxMaintenance support for astronauts
There is no better innovation model in the worldhttps://www.vttresearch.com/Impulse/Pages/There-is-no-better-innovation-model-in-the-world.aspxThere is no better innovation model in the world
Health and wellbeinghttps://www.vttresearch.com/Impulse/Pages/Health-and-wellbeing.aspxHealth and wellbeing
Smart Citieshttps://www.vttresearch.com/Impulse/Pages/Smart-Cities.aspxSmart Cities
Digital societyhttps://www.vttresearch.com/Impulse/Pages/Digital-society.aspxDigital society
From ideas to major innovationshttps://www.vttresearch.com/Impulse/Pages/From-drawing-board-to-major-innovation.aspxFrom ideas to major innovations
Passion spurs researchhttps://www.vttresearch.com/Impulse/Pages/passion-spurs-research.aspxPassion spurs research
New breed of business from cellulosehttps://www.vttresearch.com/Impulse/Pages/New-breed-of-business-from-cellulose.aspxNew breed of business from cellulose
Smart industryhttps://www.vttresearch.com/Impulse/Pages/Smart-industry.aspxSmart industry
The new agenda enhances the use of research infrastructurehttps://www.vttresearch.com/Impulse/Pages/The-new-agenda-enhances-the-use-of-research-infrastructure.aspxThe new agenda enhances the use of research infrastructure
VTT’s spin-off GrainSense puts a laboratory in farmers’ handshttps://www.vttresearch.com/Impulse/Pages/VTTs-spin-off-GrainSense-puts-a-laboratory-in-farmers-hands.aspxVTT’s spin-off GrainSense puts a laboratory in farmers’ hands
Technology enables good urban livinghttps://www.vttresearch.com/Impulse/Pages/Technology-enables-good-urban-living.aspxTechnology enables good urban living
Converting rags to design clotheshttps://www.vttresearch.com/Impulse/Pages/Converting-rags-to-design-clothes.aspxConverting rags to design clothes
Business angel speaks out: Growth from the international arenahttps://www.vttresearch.com/Impulse/Pages/Business-angel-speaks-out-Growth-from-the-international-arena.aspxBusiness angel speaks out: Growth from the international arena
Finland’s old nuclear research reactor to be decommissioned – New Centre for Nuclear Safety under constructionhttps://www.vttresearch.com/Impulse/Pages/Finlands-old-nuclear-research-reactor-to-be-decommissioned-new-centre-for-nuclear-safety-under-construction.aspxFinland’s old nuclear research reactor to be decommissioned – New Centre for Nuclear Safety under construction
New materials developed from plantshttps://www.vttresearch.com/Impulse/Pages/New-materials-developed-from-plants.aspxNew materials developed from plants
The autonomous world is already herehttps://www.vttresearch.com/Impulse/Pages/The-autonomous-world-is-already-here.aspxThe autonomous world is already here
Road safety to a new level using 5Ghttps://www.vttresearch.com/Impulse/Pages/Road-safety-to-a-new-level-using-5G.aspxRoad safety to a new level using 5G
More speed to network services with 5Ghttps://www.vttresearch.com/Impulse/Pages/More-speed-to-network-services-with-5G.aspxMore speed to network services with 5G
The rise of robotic carshttps://www.vttresearch.com/Impulse/Pages/The-rise-of-robotic-cars.aspxThe rise of robotic cars
The perfect pilot environment for Arctic solutionshttps://www.vttresearch.com/Impulse/Pages/The-perfect-pilot-environment-for-Arctic-solutions.aspxThe perfect pilot environment for Arctic solutions
Cleaner city traffic with wood-based dieselhttps://www.vttresearch.com/Impulse/Pages/Cleaner-city-traffic-with-wood-based-diesel.aspxCleaner city traffic with wood-based diesel
Salofa creates rapid tests for monitoring health and the environmenthttps://www.vttresearch.com/Impulse/Pages/Salofa-creates-rapid-tests-for-monitoring-health-and-the-environment.aspxSalofa creates rapid tests for monitoring health and the environment
Transition in the shipping industry: intelligent ship´s bridgeshttps://www.vttresearch.com/Impulse/Pages/Intelligent-ship-bridges.aspxTransition in the shipping industry: intelligent ship´s bridges
The story of Finlandhttps://www.vttresearch.com/Impulse/Pages/The-story-of-Finland.aspxThe story of Finland
We must maintain Finland as an attractive target for investmenthttps://www.vttresearch.com/Impulse/Pages/We-must-maintain-Finland-as-an-attractive-target-for-investment.aspxWe must maintain Finland as an attractive target for investment
Impulse 2/2017https://www.vttresearch.com/Impulse/Pages/Impulse-2-2017.aspxImpulse 2/2017
Intelligence for machineshttps://www.vttresearch.com/Impulse/Pages/Intelligence-for-machines.aspxIntelligence for machines
Digitalisation in closing the gaphttps://www.vttresearch.com/Impulse/Pages/Digitalisation-in-closing-the-gap.aspxDigitalisation in closing the gap
Biobased aromatics essential to the fine chemical industryhttps://www.vttresearch.com/Impulse/Pages/Biobased-aromatics-essential-to-the-fine-chemical-industry.aspxBiobased aromatics essential to the fine chemical industry
Why do so many women feel chilly indoorshttps://www.vttresearch.com/Impulse/Pages/Why-do-so-many-women-feel-chilly-indoors.aspxWhy do so many women feel chilly indoors
For Industry powers Finnish manufacturing industryhttps://www.vttresearch.com/Impulse/Pages/For-Industry-powers-Finnish-manufacturing-industry.aspxFor Industry powers Finnish manufacturing industry
Digitalisation of the shipping industry requires cutting-edge researchhttps://www.vttresearch.com/Impulse/Pages/Digitalisation-of-the-shipping-industry-requires-cutting-edge-research.aspxDigitalisation of the shipping industry requires cutting-edge research
Tracking peoplehttps://www.vttresearch.com/Impulse/Pages/Tracking-people.aspxTracking people
Leca – filtering a cleaner futurehttps://www.vttresearch.com/Impulse/Pages/Leca-filtering-a-cleaner-future.aspxLeca – filtering a cleaner future
Transport gets smarthttps://www.vttresearch.com/Impulse/Pages/Transport-gets-smart.aspxTransport gets smart
Small is big: growth and new opportunities in silicon photonicshttps://www.vttresearch.com/Impulse/Pages/Small-is-big-growth-and-new-opportunities-in-silicon-photonics.aspxSmall is big: growth and new opportunities in silicon photonics
LED foils can be bent into any shapehttps://www.vttresearch.com/Impulse/Pages/LED-foils-can-be-bent-into-any-shape.aspxLED foils can be bent into any shape