Posiva publishes Working Reports and Posiva Reports. From the year 2006 nearly all the reports have been published on our webpage and they can be found in the databank. In the databank you can also find our Annual Reviews and some other publications as well. You can also find print-quality pictures and useful links in the databank.

Recent publications

Workreport 2016-45



Results of Monitoring at Olkiluoto in 2015 – Environment


Sojakka, T., Aro, L., Lipping, T.



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In 2003, Posiva Oy presented a programme for monitoring at Olkiluoto during construction and operation of ONKALO (Posiva 2003b). In 2012 the monitoring programme was updated to concern the years 2012–2018 (Posiva 2013a). Part of the monitoring is performed by the company running the nuclear power plants on the island, Teollisuuden Voima Oy (TVO). This Working Report presents the main results of Posiva’s environmental monitoring programme on Olkiluoto Island in 2015. Results are presented under five topics: 1. Evolution of geosphere, 2. Biosphere modelling input data, 3. Interaction between surface environment and groundwater in bedrock, 4. Environmental impact and 5. Baseline of monitoring of radioactive releases.

The soil solution quality in 2015 was quite comparable to that in earlier years. Proximity of the sea and the young age of soils are seen in soil solution results.

Biosphere modelling input data in 2015 included e.g. continuous tree litterfall data and new vegetation inventory campaigns, as well as updated game statistics and population estimates of fauna, and basic monitoring data from Olkiluoto offshore properties. Interaction between surface environment and groundwater in bedrock included e.g. weather and surface water monitoring data. Environmental impact analyses included e.g. monitoring of noise, air quality, analysis of chemical composition of particulate matter deposited on needle surface, effluent waters and private drilled wells. Noise monitoring in the vicinity of ONKALO showed that in the case of raised noise levels the sources are mainly the traffic on Olkiluodontie road and noises from the ONKALO construction site. Construction activities in the area were seen in high concentrations of Al and Fe in remaining litter of the litterfall, as well as in spruce needles in the vicinity of construction activities. In the monitoring of the outlet waters of ONKALO the pH limit set in the environmental programme (9.5) was not exceeded in 2015, the limit set for suspended solids (50 mg/l) in the rock piling area drainage waters was not exceeded either. Compared to background levels, elevated sulpahte concentrations have still been observed in the surface runoff during 2015 in the vicinity of ONKALO and the rock piling area. The long-term monitoring data indicates that a general increase in levels of sulphate in the environment has taken place on the island during 2013. The water quality of the monitored private wells is poor due to their natural properties. Their water levels and water qualities are not affected by the construction of ONKALO. Generally the environmental effects of the works related to the final disposal site have remained minor.


Environmental monitoring, ecosystem, baseline condition, change


WR 2016-45_Updated_web (pdf) (19.1 MB)


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