GB No. 1(16)/95


MOHOVCE SAFETY REPORT 'HOPELESS'

THE POLISH ECOLOGICAL CLUB
AGAINST MOCHOVCE NUCLEAR POWER PLANT

Kraków, 6 Jan. 1995

Polish environment group Polski Klub Ekologiczny (the Polish Ecological Club, Friends of the Earth Poland) after a preliminary review of the environmental impact assessment of the Mohovce nuclear power plant, has damned the document as hopelessly inadequate.

The Mohovce project consists of two Soviet - designed 'VVER-213' nuclear reactors which are now 80-90% complete. Slovak electric utility SEP plans to complete them with the credit of the EBRD and Euratom. An international joint venture has been formed with Electricite De France for this purpose. According to PKE, the EIA safety documentation fails completely to provide the most important safety related detail, while providing large quantities of irrelevant information on topics of minor importance. According to a PKE analyst, John Hallam: "Before we started to look at the Mohovce safety report, we knew there were a whole series of long - standing concerns about VVER safety. The safety report reflects none of these concerns". For example, a 1989 US Department of Energy analysis of VVER safety came up with a number of concerns which are valid to this day, and are still not properly addressed. They include:

--The susceptibility of the reactor pressure vessel to radiation induced embrittlement. Because the fuel in WER reactors is closer to the walls of the reactor pressure vessel than in western reactors, VVER reactor pressure vessels become brittle faster due to the impact of neutrons, than do the vessels of other reactors, though vessel embrittlement is also an issue in older US reactors. The safety report actually admits in a couple of places that the susceptibility of the reactor pressure vessel to neutron embrittlement needs 'examination", yet the very existence of the issue for VVERs is not mentioned, and nowhere are details given on all the things one would like to know such as the alloy composition of this particular pressure vessel and hence its susceptibility to this kind of problem. and the kind of core design that will be chosen.

-- Reliability of the Emergency Shutdown (Scram) System VVERs seems to have a slow and possibly unreliable system to insert the control rods in an emergency. A fast and reliable emergency shutdown (Scram) system is essential for reactor safety, yet in certain circumstances, for example, in case of an electrical fault. the scram system in a VVER213 reactor may not work at all. The EIA Safety Report should have provided details of the kind of emergency shutdown system installed, and of whether they plan to alter it None of these crucial safety details are in the report.

Other matters raised in the 1989 DOE report include the effectiveness of the confinement and 'bubbler tower' system, the vulnerability of the plant to an aircraft crash, protection from flying debris in case of the self - destruction of one of the plants turbo - generators, and the effectiveness of the emergency core cooling system.

In addition, the Mohovce plant could become a target for terrorist activity as it lies in a potentially unstable part of the world, a possibility not even mentioned in project documentation.

The safety report contains no real analysis of any of these matters. Rather, it tends to concentrate on secondary matters such as pipe - whip, fire protection, and a number of piping changes which it fails to explain properly.

It also lacks basic information. For example, nowhere does it contain a diagram of a VVER plant, let alone this particular WER plant. Nor does it contain proper site or layout maps.

Finally, the 'detailed' appendices to the report display a fragmented approach, reading as if no - one had ever taken a look at the whole thing to see how it fitted together. The approach is also frequently legalistic, with the authors more concerned to demonstrate that they satisfy the letter of Soviet or Slovak or IAEA requirements than that what they plan is actually the best and safest thing to do.

It is our opinion that the EBRD and the governments concerned should take a very dim view of this thoroughly unsatisfactory document, and throw it out, and the whole Mohovce project with it.."

Tomasz Terlecki

* * *

Kraków, l7th Feb. 1995

Polski Klub Ekologiczny, Polands largest and oldest environmental organisation, submitted on 17th Feb. 1995 its formal comments on safety aspects of the Mochovce nuclear power plant to the EBRD, Slovensky Energetiky Podnicky (SEP), and Electricite De France (EDF). Friday 17th was the formal end of the public participation process being held by the EBRD under its environmental protection guidelines.

PKE and 20 international environment groups including FOE International, Greenpeace, and Global-2000 have lobbied strongly for the period of public participation to be extended for 30 days, on the basis that the process has been flawed and that the documentation is inadequate.

In addition, PKE argues that the safety and EIA documentation released by the project proponents,

SEP and EDF, is so bad that it should be withdrawn and the entire process of public participation should be started again. According to PKE, the safety documentation in particular, contains such gross deficiencies that it is totally unsuitable for use as a basis for public comment.

The documentation actually fails to even acknowledge the existence of major safety problems that are common to all VVER power plants, let alone deal with them in any acceptable way. These problems include neutron embrittlement of the reactor pressure vessel, an unreliable emergency shutdown system, and an 'accident localisation system' that, according to calculations done in Poland, will collapse if exposed to the stresses of a major accident.

Comments by Professor Niewodniczanski on Polish national TV last night to the effect that PKE is ignorant and doesn't know what we are talking about, neglect a few important matters. PKE has relied heavily in its analysis on material from two sources: from the IAEA, who surely can't be accused of ignorance, and on analyses done for the IAEA by Janisław Zwolinski and Leon M. Kolodziejczyk in 1989-90. These people were then associated with Warsaw Technical University and the Polish Atomic Energy Commission of which Professor Niewodniczanski is the head. ggProfessor Niewodniczanski's should desist from this kind of politically motivated comment, and should start by actually reading what PKE has said, and consult Zwolinski and Kolodziejczyk, who have done the analyses for the IAEA.

A major accident at Mochovce could happen if the reactor pressure vessel at Mochovce cracked, which might happen due to neutron embritttlement. A sufficiently big accident could produce a radioactive plume up to 1000Km long (the plume from Chernobyl was 1500Km), which would contaminate not only the whole of Slovakia with a SW to NE wind, but the whole of Southeast Poland, including Cracow, Bielsko, and up to the Byelorussian border.

This means that it is very much in Poland's interest to ensure that the Mochovce project does not proceed. The Polish governmment must act in conjunction with that of Austria to impress on Slovakia that the completion of Mochovce, either via the EBRD or by other means is unacceptable and would create an international issue.

* * *

Editor's note: Below we publish some excerpts from PKE comments on safety aspects of the Mochovce Nuclear Power Plant. The whole document is 24 pages long and can be obtained from the Club.

COMMENTS BY
POLSKI KLUB EKOLOGICZNY
ON MOCHOVCE NPP SAFETY

The following comprises comments on safety aspects of the EIA for the Mochovce Nuclear Power plant. As there has been a relatively short period of evaluation of the EIA and the Safety Report, due entirely, to the late arrival of the documentation, it is in no sense exhaustive. However, it does spotlight what we believe to be major problem areas with the EIA and safety documentation.

In general, the EIA follows a clear pattern of refusing to deal with safety issues that are of greater consequence and less easy to solve, while providing reams of detail on less relevant and important matters. Matters with which the EIA and Safety Report do not deal adequately and which are of high safety importance include reactor vessel embrittlement, scram or Az system adequacy, the adequacy of the bubbler tower/accident localisation system, primary to secondary leakage, and internal hazards (such as high-pressure steam, flooding, fire and turbine missiles, especially in the area of the 14.7m level of the Intermediate Building).

Instead of dealing with these matters, which should be of lop priority, the EIA and its associated documentation deals at length with matters such as fire protection, pipe-w hip, changing aluminium for stainless steel insulation, and some changes to piping in the area between the reactor and the turbine hall, as well as providing considerable detail (but no context) on changes to the borated water system and the pressuriser letdown system. While the changes to piping are by no means unimportaut, SEN/EDF fails to provide adequate solutions to the problems these changes were supposed to solve, while critical areas such as RPV integrity and the scram system are dealt with in a grossly insufficient manner.

The changes proposed to certain areas such as the ECCS (emergency core cooling system) and the AZ (scram or emergency shutdown) system are not adequate, and the nature of these changes is exceedingly vague. The EIA and associated documentation (especially AnnexB) abound in generalised statements of principle or guidelines to be followed in performing tasks such as operating a scram system, without once mentioning the actual nature of the system involved.

The EIA documentation is on the other hand, very slim on detail where detail is important. For example, nowhere does it say what system is actually used for the emergency shutdown (Scram or AZ) system, and nor is there any diagram of this crucial piece of safety equipment. Is the AZ system the rather unsatisfactory 'second modification' common to VVER213 reactors, in which rod insertion is slowed down (and may be accidentally reversed) by the rotational friction<m of an attached motor? Is it a gravity-drop system? Is it a VVER320/1000 or PWR style magnetic jack system? IAEA Tecdoc742 does provide such a diagram, but we are told that the Mochovce scram system is a different, 'improved' one, though this is not clear.

The EIA documentation is equally vague about the steel of the current reactor pressure vessel, its susceptibility to embrittlement, monitoring and sampling programs, the possibility of annealing the RI'V, and other topics relevant to the embrittlement question. Vague statements of principle are made about the desirability of monitoring, but that is all.

Yet there is abundant detail where it is not needed for example, there is a quite incomprehensible diagram of the pressuriser letdown system, but no real idea where it fits in with other systems, nor of what its significance in the overall safety picture might be.

No overall plant layout and no site plan are provided. There are no engineering diagrams of a more general nature, such as sectional views showing the layout of main steam lines, turbines, position of the control - room, the bubbler tower, and so - on.

The EIA should provide a map of waste disposal facilities, switchyards, the plant site boundary, accommodation, administration buildings, water supply facilities, ncarby villages, road and rail connection, high-tension lines, etc. This is not done.

In general the documentation is lacking in detail, but it is especially lacking in crucial detail relating to critical and ongoing VVER safety issues.

Annex-'B' of the Safety Report in particular, displays a fragmented approach. Annex 'B' reads as if nobody has ever read the whole thing to sec how its parts fit together. Annex'B' also frequently displays a purely legalistic approach. It frequently says things like "satisfies Czech (or Soviet or IAEA) safety requirement such - and - such', rather than attempting to show that the system concerned will in fact work properly in all the situations in which it will be required to work.

This tendency is especially evident in R 1.2.1. dealing with fire protection according to which 'any tire starting anywhere must remain confined within limits that are known in advance and defined in a document'(!) This, surely, is bureaucracy gone mad. One would have thought that prevention and prompt extinguishing of the tire was more of a priority.

Similarly, B20 which deals with the scram (Az) system is at pains to demonstrate that the existing system conforms to IAEA 50 SG D3, and that its 'study' must conform to 3 IAEA guidelines and two US codes, while B10, dealing with RPV embrittlement, immediately refers to 'Russian and Slovak statutory prescriptions'.

In general, models or standards of reference by which the EIA, Safety Report, and appendices A and B may he judged can be found in DOE/NE0086, IAEA Tecdoc742, and the IAEA's VVER-RD-074. These documents supply much of the crucial information about the material of the RPV, the Scram system, and bubbler - condenser tower structural integrity that is notable for its absence in the safety documentation supplied by SEP/EDI . That crucial information that really should have been included in the safety documentation has had to be obtained elsewhere even from documents that are not officially available to the public is a damning indictment of the standard of the SEP/EDF-supplied safety' documentation.

Ironically, at least some of the information that SEP/FDF tries so carefully to keep from public review, notably that on RPV safety, could actually strengthen its safety case. SEP/EDP does neither the public nor itself any service by keeping, for example, information on RPV material to itself. No truly meaningful discussion of Mochovce safety can take place unless this information is on the table. (...)

CONCLUSIONS

The issues dealt with (RPV integrity, Scram system reliability, and the structural integrity of the bubbler condenser tower component. of the accident localisation system are by no means the only safety issues that affect the Mochovce plant. They are however, probably the most serious and pressing ones. At the same time, they are the very issues least coherently dealt with by SEP in Appendix B, Appendix A, the Safety Report, and the EIA. SEP/EDFs failure - or possibly refusal - to deal adequately with these three most crucial issues, all of them well known and generic to VVER reactors, casts doubt on the acceptability of the EIA and safety report as a whole. It is PKE's contention that SEP's failure to deal properly with these issues in its project documentation reflects both a lack of understanding of the requirements of EIA procedure, and a lack of emphasis on safety.

SEP/EDF fail also to deal adequately with a range of other issues including turbine missiles, seismic qualification of the plant, aircraft impact, primary-to-secondary leaks/main steam generator manifold rupture, and internal hazards (fire, flooding, pipe-whip) and the associated problems of equipment qualification and the special hazards of the 14.7m Intermediate Building level itself. Of these, we have looked at the last two in detail. AppendixB devotes much space to pipe - whip problems and the problems of the 14.7m level, but its analyses and solutions are neither convincing nor adequate, and may well increase hazards in the bubbler - condenser tower.

It also casts serious doubt on the safety of the Mochovce power plant, an accident at which could have the gravest consequences for Vienna in one direction, and Southern Poland (not to mention Northern Slovakia) in the other direction.

An accident at Mochovce could be very serious indeed. The most serious accident that could possibly happen would be a complete fracture of the RPV, an event that in the case of the VVER 230 analysis conducted by DOE would have propelled the RPV head together with the control - rod drive assemblies out through the protective dome of the confinement system and out of the surrounding building, resulting in a core meltdown with immediate release of radiation to the environment. Such an event would produce a plume of radiation as long as 1000Km, that would affect all of Northern Slovakia and would blanket the whole of south-east Poland.

A 'cold - leg LOCA' supposedly the design-basis accident for the VVER213, would be contained only if the bubbler-condenser tower functioned exactly as designed. Since the indications are that parts of it would in fact collapse, a major release of radiation would also result from such an accident.

The treatment of these issues reflects a standard of documentation and practice that, if reflected in the Mochovce project itself, means that the project should not be approved. In addition, the documentation itself should be rejected as insufficient for proper public review, and the entire process of public comment recommenced with new and adequate documentation.

John Hallam
Nuclear Campaigner for FOE Australia)
Consultant to PKE
Polish Ecological Club -National Board
ul. Piłsudskiego 8, 31-109 Kraków, Poland
tel./fax: 48/12/21.88.52
E-mail: uedabrow@kinga.cyf-kr.edu.pl


GB No. 1(16)/95 | Contents