Preliminary safety judgement on the application for a fifth nuclear power plant

Teollisuuden Voima Oy in December 2000 submitted to the Finnish Government an application for a Decision-in-principle in accordance with the Nuclear Energy Act for the construction of a fifth nuclear power plant. According to the application, the new nuclear power plant unit would be located on the site of either Loviisa or Olkiluoto nuclear power plant.

In February 2001 STUK issued to the Ministry of Trade and Industry a preliminary safety assessment and a statement about the application. Attached to the statement is an assessment by the Advisory Committee on Nuclear Safety. The safety judgement was supplemented on account of the terrorist attacks on the United States on 11 September 2001. The supplement and its accompanying note were handed over to the Ministry of Trade and Industry on 7 January 2002.

In the preliminary safety assessment, the Finnish Radiation and Nuclear Safety Authority notes that the nuclear power plants introduced in the application for a Decision-in-principle submitted by Teollisuuden Voima Oy to the Government can be constructed such that they meet Finnish safety requirements.

Since the plans for the new facility are supported by 30 years of experience in the use of nuclear energy it can be expected that a new plant based on any of the suggested concepts could be constructed safer than those already in operation.

None of the plant concepts in TVO's application do, as such, meet all Finnish safety requirements. The necessary design alterations could be made during the construction licence application phase in case the project is carried on.

STUK notes in its statement that there is still such competent personnel in Finland as is necessary in the implementation of the power plant project.  This, too, would facilitate the construction of a fifth nuclear power plant at this point of time.

Buyer must have more know-how than in the past

Teollisuuden Voima Oy's Olkiluoto plant was delivered on a turn-key basis. It would seem that the vendors do not currently accept overall responsibility for a facility the way they used to and the buyer must thus have more know-how than before.

According to STUK, TVO must develop its organisation, working practices and and know-how during the possible construction phase to take responsibility for safety planning for the facility's entire operating life.

Provision must be made for impacting large aircraft

Because of the terrorist attack on the United States on 11 September, the Ministry of Trade and Industry requested the Radiation and Nuclear Safety Authority to supplement its preliminary safety assessment. STUK submitted the additional document to the Ministry on 7 January 2002.

The original safety assessment notes, among other things, that if a small, single-engined airplane impacts the facility, significant radioactive releases into the environment may not occur. Assessments prior to September 2001 made provision only for accidental aircraft collisions. The crashing of a large passenger airplane to a Finnish nuclear power plant was assessed as highly unlikely, considering flight routes and traffic densities in the vicinity of plant sites.

Provision must be made for an impacting large passenger or military plane

It is noted in the supplement to the preliminary safety assessment that even the impact of a large passenger or military plane may not incapacitate the nuclear power plant's safety functions immediately after the event. The consequences of the collision, e.g. a fire, may not bring about a situation during which a significant amount of radioactive substances could be released into the environment. The radiation dose equivalent allowable from the release is similar to that of a design basis accident. Provision made for impacting planes will protect the facility even from other external threats and malicious damage.

The new angle means that the design and construction of the power plants introduced in TVO's application for a Decision-in-principle whould be somewhat different from the original plans. STUK has not made facility-specific assessments of how the facility concepts presented in the application meet the new safety requirements. According to STUK the structural designs of all the plant concepts would require some modification. However, none of the proposed power plant types would be need to be rejected based on current knowledge.

More information

• Preliminary safety judgement (191.79 kilobytes)
  and a statement (PDF, 10 K, in Finnish)
• Assessment by the Advisory Committee on Nuclear Safety (PDF, 33 KB, in Finnish).
• The supplement and its accompanying note (PDF, 50 KB, in Finnish)