(May 8, 1998) The probability that reactor unit two in Oskarshamn in southeastern Sweden will experience a meltdown is 25 times greater than what the IAEA recommend as "safe standard". So says a Probabilistic Statistical Analysis commissioned by Sydkraft, the reactor's owner.
(491.4869) WISE Stockholm - The Oskarshamn-2 reactor has only two independent electrical systems, not four, as newer Swedish reactors have as standard). A recalculation of the probability of serial malfunctions that might precipitate a meltdown resulted in an overall chance of 1 in 4,000 during any given year. The IAEA recommendation is a risk of 1 in 100,000 reactor-years.
The two reactors at Barsbaek, across the Sund from Copenhagen, are in the same state, with each having only two independent systems, as it turns out. This became public knowledge as a sidelight to the Oskarshamn-2 report on April 29. (The report of a similar study of the Barsebaeck reactors--also Sydkraft's--is expected in June.)
The improvements made at Ignalina over the past year or so make it "safer" than Sweden's Oskarshamn-2 or Barsebäck-1 and 2. Safer in terms of probability, that is. A meltdown at Ignalina remains a potential disaster, since the Ignalina plant still lacks anything near adequate containment.
SKI: "Not to worry!"
According to the Sydkraft report, which was addressed to the Swedish Nuclear Power Inspectorate (SKI), the problem is not one of faulty details but of "a fundamental systems design fault". A phrase like that makes most people start thinking about shutting down, "calling it quits" before the worst is a fact. Former Prime Minister Thorbjoern Faelldin terms closing Oskarshamn-2 "the logical conclusion", as do the Greens, Center Party, Greenepeace-Sweden and, of course, the Swedish Anti-Nuclear Movement. All have gone on record calling for closure of Oskarshamn-2 and the Barsebäck reactors.
But not Sweden's Nuclear Power Inspectorate, SKI. No, SKI feels that an "understanding approach" is the best way to maintain an open dialogue with Sweden's nuclear operators - and in this they excel. Lars Gunsell, SKI's spokesman, told the press on April 29 that SKI does not consider "25 times more dangerous than IAEA's recommendation" a significant deviation. "It falls well within the range of values that pertain to the concession to operate," he assured listeners to Swedish Radio's P1.
News coverage of the Oskarshamn-2 report also revealed that the Swedish authorities have no probabilistic (statistical) criteria of safety. The SKI spokesman defended this policy but, when pressed by journalists on that point, had to concede that "of course, we reach a point of no return somewhere along the line".
Has Oskarshamn-2 reached that point? Perhaps. For, on the radio again the next day, the same Lars Gunsell argued that the statistics should not be taken too seriously. The statistical margins involved in the calculations are all too large for the results to be "realistic", he said.
"Why, then," asked the journalist, "does IAEA bother to make a statistical recommendation?" And Gunsell's reply was, "Well, the figures are a sort of indication." (An indication of what remained unsaid.) A similar but (according to SKI) less precise analysis one year ago came to the same result about Oskarshamn-2. SKI excuses its silence with the lack of precision in the study. According to the Aftonbladet the SKI considers the present one more accurate.
The spokesman's seeming sangfroid is contradicted somewhat by the fact that SKI did write to the operator, OKG, earlier in April and called for a plan for corrective measures before June 15, according to an article in Dagens Nyheter.
Phaseout? Well...
What SKI has in mind is increasing Oskarshamn-2's power reserves, not shutting down. Sweden's Minister for the Environment Anna Lindh takes a characteristic 'middle position'. Interviewed by telephone in the US, the minister called the findings "another example which speaks for phasing out nuclear energy in the long term. Nuclear energy is not the safe source we once thought, and for that reason it is not sustainable in the long run". She went on to say that the Oskarshamn-2 reactor "should be shut down unless effective measures can be taken". [SVT1, 29.4), emphasis added]
As readers of the WISE News Communique are aware, Sweden has taken what some consider (and many more hope will be) the first step in winding down the country's heavy nuclear commitment. In February the Swedish government moved to close Barsebäck-1 this coming July 1. The decision is being contested in litigation, however. (Sydkraft's first appeal to the European Union failed, it might be noted.)
Ironically, Sweden angered the Lithuanian government some months ago when a spokesman urged international measures to help the country shut down Ignalina because of the threat the plant posed to the rest of northern Europe. Former Prime Minister Fälldin referred to this Swedish attitude in his recent statement: "For years now, nuclear enthusiasts have been arguing that we should keep our 'safe' Swedish reactors and shut down the ones in the former Soviet Union." He added: "If, as they say, Ignalina should be shut down because it is such a threat, it seems only logical that Oskarshamn 2--which we now know to be less safe than Ignalina--should be shut down, too!" (SVT1, 29.4)
Ignalina has been used as a whipping post almost daily since the government moved to close Barsebäck-1. Now it seems that--even for those who cherish Barsebäck most dearly 'the threat' has come closer to home!
Source:
- "Risk för härdsmälta en procent", Dagens Nyheter, 29 April
- Aftonbladet, 29 April
- interviews heard on Sveriges Radio/P1, 29 & 30 April
- Sveriges Television/SVT1, 29 April 1998
Contact: WISE Stockholm