Preliminary studies for the decommissioning of reactor sections and the construction of a radioactive waste disposal site at the Paldiski nuclear site 2014 - 2015
To train submariners in the Soviet Union's Northern Fleet and Pacific Fleet, two military training reactors, similar to those used on nuclear submarines, were installed at a naval training centre on the northern tip of the Pakri Peninsula. The purpose of the training reactors was to (re)train the marines in conditions as close as possible to real conditions before they were sent to submarines.
Nuclear Reactor No 1 operated from April 1968 to January 1989 and was housed in a metal enclosure similar in shape and dimensions to a nuclear submarine. The reactor was of the PWR/VM-A type, with a thermal power of 70 MW. In 1980 the reactor was refuelled. The total operating time of reactor No 1 (at 20-40% load) was 20 821 hours (13 781 hours with the first fuel load and 7 040 hours with the second load).
Reactor No. 2 was of the PWR/BM-4 (LWR) type, with a thermal capacity of 90 MW, and operated from February 1983 to December 1989 with a load of approximately 30%. The reactor was not refuelled. The total operating time of reactor No 2 was 5 333 hours.
The fundamental decision to close the training centre, or the Paldiski site, for safety was made in 1991 after Estonia's independence was recognised by Russia and Russian troops were withdrawn from the area. Until 1995, the following work was carried out by the Russian authorities to ensure the long-term safety of the reactor sections:
- spent fuel was removed from the reactors and shipped to Russia;
- the auxiliary sections were dismantled;
- non-radioactive equipment was removed;
- reactors and primary containment piping were drained of as much liquid as possible and made airtight;
- the cooling water purification filters were drained;
- non-radioactive devices above the biological shield (a water column surrounding the reactor to capture neutrons) were removed;
- the support structures of the reactor sections were strengthened;
- reinforced concrete sarcophagi were constructed and several radiohazardous nodes and openings inside the reactor sections were filled with concrete.
According to the agreement concluded between the Russian Federation and the Republic of Estonia (30 July 1994), the training centre, together with the buildings of the training reactors and the nuclear waste storage facility, passed into the possession of the Republic of Estonia on 26 September 1995.
Between 1995 and 2011, extensive conservation, clean-up and reconstruction work was carried out at the former military site in Paldiski, because of the large amount of radioactive and non-radioactive residual contamination that was a threat to surface and groundwater and soil. Among other things, a number of buildings were cleaned up and demolished, and an interim storage site for radioactive waste was built in the main building.
As a result of the European Union (EU) project “Evaluation of Management Routes for the Paldiski Sarcopahagi”, carried out in 1999-2001, the project's expert committee found that from the point of view of radiation safety and waste storage, it is expedient to start the final decommissioning (deactivation and complete dismantling) of the reactor sections, which are the main source of residual contamination at the site, after 50 years of storage, i.e. in 2040.
In the framework of the EU PHARE project “Safe Long-Term Storage of the Paldiski Sarcophagi & Related Dismantling Activities”, which was carried out between 2005 and 2008, an air drying system was installed in the sarcophagi to improve corrosion resistance in order to improve the storage conditions, a monitoring system was installed in the reactor sections to detect possible contamination leaks and the main building surrounding the reactors was renovated to improve the weatherproofing of the building.
When making its decision, the expert committee of the project „Assessment of alternatives for the management of Paldiski reactor sections“ assumed that the radioactive waste generated during the decommissioning of the reactor sections starting in 2040 will be disposed of at the latest in the radioactive waste disposal site established by that time. The interim storage facility, which was built in 1997, has been designed to accommodate all the waste generated in Estonia (including the radioactive waste from the nuclear waste repository). The storage facility is designed to accommodate all radioactive waste generated in Estonia (including radioactive waste generated during the decommissioning of the Paldiski Nuclear Submarine Training Centre nuclear facility and waste removed from the Tammiku radioactive waste repository), with the exception of waste generated during the decommissioning of reactor sections. Therefore, the start of the environmental, technical, etc. analyses and studies necessary for the decommissioning of the reactor sections must be accompanied by the start of the environmental, technical, etc. analyses and studies necessary for the construction of the disposal site, as the results of the implementation of one activity will feed into the implementation of the other activity and vice versa. The aim of this project is to carry out the initial technical studies and to collect the necessary data to serve as a basis for the planning of further activities, for decision-making and for the initiation of environmental impact assessments.
Completion of the project will pave the way for the start of the environmental impact assessments for the decommissioning of the reactor assemblies and the construction of a radioactive waste disposal site. Following the environmental impact assessments, the design and construction of the disposal site and the decommissioning of the reactor sections can already start.
For more information on the history of the Paldiski site:
The ex-ante activities are:
- Organisational activities of the project (seminars and reports)
- Data collection and overview of national and international requirements
- Identifying options for decommissioning reactor sections
- Identifying options for the disposal of radioactive waste
- Costs of treatment, decommissioning of reactor sections and disposal costs.
- Communication strategy
Preliminary studies will be carried out in the period from 23.09.2014 to 30.12.2015 by a consortium of JSC Eksortus (Lithuania) and R&D Company SOSNY (Russia), with the participation of FCNRS (Federal Center of Nuclear and Radiation Safety, Russia) and JSC Specialus Montazas-NTP (Lithuania) as subcontractors.
The preparatory studies will be financed by the Cohesion Fund of the European Union.
The Estonian partner of the project is AS A.L.A.R.A., which is responsible for the management and safety of the Paldiski site, whose contact person is Ivo Tatrik, phone 6741 366, mobile 51 51 111, e-mail ivo.tatrik@alara.ee.