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4. Koeberg Nuclear Power Station 4.1 Our legacy ?– starting off on the wrong foot? Eskom's Koeberg Power Station started operating in 1984 and is the only commercial nuclear power station in Africa. It is situated at Duynefontein, 27km north of Cape Town on the Atlantic coast. Eskom argues Koeberg provides reliable electricity to the Western Cape, and supplies 6,5% of South Africa's total electricity needs. In addition, Eskom claims that Koeberg It has operated safely for more than 17 years and will operate for another 20 to 30 years. There are proponents who argue that the investigation into the siting of Koeberg was flawed, and that the area lies within a seismic fault zone that has seen a number of serious earthquakes over the past century (between 1620 and 1971 a total of 73 earthquakes were recorded in or near Cape Town), the most recent being the Ceres quake of 1969 which had a magnitude of 6.3 on the Richter Scale (Wullschleger, 1999). Criticism was levelled at the site selection criteria by Cape Town City?’s Medical Officer at the time, Dr R.J. Coogan who raised concerns about Koeberg?’s proximity to Cape Town and the inadequate measures put in place to deal with an emergency where radioactive releases were present (Cape Argue, 23 June, 1983). The Cape Town City Council raised concerns in 1984 ( Cape Times, 19 December, 1984) that Koeberg was located too close to Cape Town. The memorandum was endorsed by the Executive Committee who also expressed dissatisfaction at the nature of the emergency procedures demonstrated by Eskom. International Atomic Energy Agency guidelines suggested a minimum distance of 80km from inhabited areas yet these have been ignored. New guidelines suggest that this limit may be relaxed, and in some cases in France it has been argued that the exclusion zone may be as little as 5km. The proponents of the PBMR argue that the safety zone may be relaxed to 400m from the site of a PBMR. From the onset, Koeberg nuclear power plant was beset with problems. As an example in August 1983 Framatome of France sent a repaired set of 18 control rod drive mechanisms to Koeberg. The plant underwent re-welding and was checked for leaks as a result of the disclosure that the Framatome-supplied plant had an under-cladding cracking problem.(Nucleonics Week, 4 August 1983, p.7; Nucleonics Week, 1 September 1983, pp. 9-10). Again, in Februrary 1985, Koeberg was shutdown due to faults detected in the stainless steel piping supplied by Framatome (Cape Argus, 25 February, 1985). However, this was not the case in the alleged supply of faulty thermocouple seals supplied to Koeberg by Framatome in 2001 (Le Monde 18 June, 2000). This event has never been adequately investigated or reported on despite requests from watchdog organisations. But over the years a number of incidents have started to raise concerns surrounding issues at the plant such as fatigue of workers, quality of parts supplied to the plant, errors of judgement on the part of workers. Some of these incidents are highlighted below: In 1985 Koeberg goes off stream until 22 June 1985 after ferritic inclusions are found in a stainless steel elbow joint at Koeberg-2. Ultrasonic testing is called for all pipe fittings in the primary loop. Loss of revenue is estimated at R90-million, while investigation is said to have cost R6-million (Sunday Times 7 April 1985; Cape Times 25 February 1985; Cape Times 26 November 1985): During 1991 high concentrations of Strontium-90 are detected during the first quarter of 1991 in sludge from Melkbos Sewage Works. An activity of 5,97Bq/kg was measured, which is approximately 12% of the Reporting Level (50Bq/kg). The reporting level of Strontium-90 for instance, in drinking or fresh surface water is 68,4Bq/l (kg). (Peter Bester, Deputy Manager, Koeberg Project, National Nuclear Regulator). It was not initially thought that radioactive material would have found its way into the sewage systems, and though the levels were smaller than the accepted dose limits (according to Eskom and the NNR) concerns were raised by the City health officials that this presence may indicate unanticipated releases of Strontium-90 into the environment from a plant where assurances were given that there would be no cause for concern around radioactive releases; Then in 1997, Three Eskom employees received ?“unplanned?” doses of radiation during a routine shut-down at Koeberg, after contravening safety procedures. They enter a high radiation area within the reactor containment building without protective clothing and receive doses of 50, 90 and 105 mSv respectively. The incident is classified as level two on the INES scale (NucNet News no.141 14/3/1997; The Argus 13/3/1997; Weekend Argus 3/5/1997); In September 1998 The Council for Nuclear Safety monitors the investigation of faults which caused the shutdown of both turbines at Koeberg. This is the first time in the history of the Western Cape power station that both units have been shut down simultaneously. Brian Statham, national energy manager for Escom, says that a fault in Koeberg-2 occurred during routine testing when an ?“unexpected vibration?” was found (The Star, 17 September 1998); In 2000, The International Council for Radiological Protection (ICRP) recommends the limitation of annual occupational exposure for a worker at a nuclear power station to 20 mSv. (38) It reports that during 1999, 1 756 people were occupationally exposed to levels that exceded this guideline, at Koeberg. The total collective dose for the workforce was 1 726.4 mSv versus a target of 2 Sv. The annual average dose for the occupationally exposed work force was 0.98 mSv. The highest individual dose was 20.35 mSv (US Nuclear Regulatory Commission Papers SECY-00-0034 2000); In late November 2001, Officials at the Koeberg nuclear plant admit ageing equipment caused a malfunction which blacked out most of the Western Cape six weeks prior. This was despite an initial denial that Koeberg was the cause for the blackout at all. Immediately after the shutdown Eskom publicly stated that there was "no problem" at Koeberg. An Eskom spokesperson said after the power cut in October that a fault at a Beaufort West transmission facility had caused the plant to shut down. "We are investigating whether coils on the control rods which were dropped into one of the reactors during a routine test last month were worn out, causing them to slip too far into the reactor," said Karin de Villiers, a spokesperson for Koeberg (Cape Argus, 28 November, 2001); In a December 2000 edition of the television programme Carte Blanche, a story was aired highlighting the controversy surrounding thermo-coupling seals supplied by Framatome in France in 1995 to Koeberg and now under scrutiny in an identical plant in Huy, Belgium. Although Escom?’s Tony Stott and the NNR?’s Phil Metcalfe deny any breach of procedure, evidence was led that the seals were supplied without the full documentation necessary for verification; In June 2002 Business Day investigations highlight the fact that Eskom has 18 years worth of accumulated dehydrated sewage sludge that has acquired elevated radioactivity through being mixed with waste water from the Koeberg laundry, where protective clothing is washed after exposure to radiation. A plan to dump the radioactive sludge along with other at the Vissershok hazardous waste site near Table View was vetoed by a Health Department radiation protection official, who noticed that the sludge was almost eight times more radioactive than the minimum standard set by the National Nuclear Regulator for waste destined for a landfill site. Koeberg spokesman Carin de Villiers confirmed that the radioactivity of the sludge was measured at 1,5 Becquerel (Bq), compared with the maximum of 0,2 Bq dictated by the national standard for landfills (Business Day, 2 June 2002); On the 11 November 1991 tube damage caused by escaping gas caused a shutdown on the plant (No Nukes Info Source, December 2003). The problems are attributable to aging; On 28 May 1997 it was reported that accidental leaks have twice that year exposed workers to radiation, in early March and May. o In the first case the exposure was below the levels set by the Council for Nuclear Safety (32 mSv) but higher than the in -house limits that Eskom set for itself. The CNS limit is 50 mSv a year while that of Eskom is 20 mSv. In the second case, the exposure that was suffered was approximately double the annual limit that the CNS or NNR sets. In the first case, a worker went into an area which was off-limits. o In the second case, which involved three workers, it seems that one of the pieces of equipment that the workers were using to monitor the radiation that they were being exposed to was defective ( the monitor under-read the radiation levels by a factor of 1000) and therefore they were not aware of the fact that they were being exposed to higher levels than they ought to be. They received exposures of 91, 72 and 41 mSv respectively (Cape Times, 14 August, 1998). They dose they received was the same as and 8 ?– 120 year exposure. Questions arise as to what work allocation these employees are now faced with given the levels of radiation exposure. This also supports incidents where workers from Vaalputs were exposed to high doses of radiation and no reporting was done until members of community groups and the trade unions fought the issue (Kantey, pers.comm.; Elbrecht, pers.comm.) Conclusions: Accidents are under-reported at Koeberg Nuclear Power Station (Noseweek, February 2004); Normal operations of nuclear installations are subject to routine emissions of low-level ionising radiation and radioactive particles in air-borne suspension; This is particularly important in light of the revelations of the Lockwood Case (Noseweek, February 2004). Serious incidents occurring at Koeberg which appear attributable to human error and ageing equipment Recommendation Given the emerging pattern of occurrences and incidents, and the pattern of initial denial, Earthlife belives that there are solid grounds for further examination into the nature of the information that is publicly declared by Eskom. Earthlife Africa is calling for: A commission of inquiry into ageing equipment risks; and, a full independent commission of inquiry into health risks and issues being faced by the workforce at nuclear facilities, and the communities surrounding nuclear facilities. ?? |
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