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Nuclear power and the shape of things to come |
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From Windscale to Three Mile Island to Chernobyl, nuclear incidents have caused devastation the world over. In this exclusive report FIRE correspondent Tony Prosser asks whether the fear reflects the risk by analysing the level of danger we currently face, including from suicide bombers
AS A HAZARD, RADIATION GENERATES A dread far beyond the hazards associated with chemicals, biological and conventional materials. Not withstanding the deliberate use of nuclear weapons during the Second World War, up to the year 2000, there have only been 27 fatal accidents with a total of 75 fatalities including the disaster at Chernobyl in April 1986, which was the most serious with 29 firefighters and plant workers dying of radiation poisoning.
Nuclear Catastrophies
For firefighters, both local authority and more especially, those employed at nuclear installations, the risk is very real. With the proposed relaxation of planning processes and an apparent sea change in government attitude to the increased use of nuclear power for the generation of ‘clean’ electricity, it is likely that soon there will be a large increase in the number of facilities in the UK and the raised potential for accidents during transportation and, less likely, during use. In addition to the potential for accidents, recent events have shown just what effects can be achieved using a few grams of radioactive materials. The murder of Alexander Litvinenko has been described sensationally by some as a dawn of an era of nuclear terrorism, although the evidence shows the difficulties of using Polonium as an alternative to the use of readily available guns, mean that the widespread use is unlikely. What the Litvinienko affair does demonstrate is the complications that can arise from the spillage or deliberate release of radioactive materials in the community and has provided a unique opportunity to consider how the Fire and Rescue Service may need to respond to these incidents.
A recent incident in Edinburgh, caused by the discovery of a number of low strength sources left in a school, necessitated the mobilisation of a full response to the incident of all the emergency services and used the national arrangements for incidents involving radiation (the NAIR scheme). The incident was dealt with quickly and the materials handled safely but it does highlight the concern with how incidents are viewed. It also showed how the response to such events has been refined over the years and that sophisticated means of dealing with radiation have evolved. Given the high level of concern, these events are likely to involve the Fire and Rescue Service, at least in the initial response phases.
Windscale
The likelihood of a major nuclear incident involving a nuclear reactor has diminished as equipment has become more sophisticated and lessons have been learned from previous accidents. Up to 2000, there had been only nine incidents involving fatalities involving 38 fatalities at nuclear installations. From a UK perspective, the most serious event occurred in 1957 at Windscale in Cumbria, subsequently known as Sellafield.
During part of a routine maintenance operation of October 7, 1957, the temperature of uranium elements (tubes of uranium pellets) began to rise. By the afternoon of October 10, the pile was on fire. Operating staff struggled to remove unaffected elements while scientific staff evaluated various strategies for extinguishing the fire – shutting off the air supply or inerting the atmosphere using carbon dioxide or argon.
At 2330, the fire appeared to be spreading. At this point, it looked likely that water might need to be used and the works fire brigade was summoned. Firefighters watched while process operators removed elements from the hot zone to create a fire break. At 0100 the Chief Constable of Cumberland was notified of the fire and a pre-determined emergency plan was put into operation. A tanker full of carbon dioxide was pumped into the core of the reactor as a final attempt to smother the fire but the blaze intensified. Fearful of the flames burning through the biological shield the scientists reluctantly opted for the option of last resort – water.
As the sun rose on the Friday morning four hoses were connected to scaffolding poles that had been fed into the core of the reactor. At 0900 (incidentally, the delay was caused by the change of shift at the fire station!), water was injected into the core. When the anticipated explosion from the ignition of the hydrogen and carbon monoxide failed to materialise, the scientists knew they had won the battle and within 24 hours the fire was extinguished and a catastrophe had been averted. There remained, however, the problem that particles of radioactivity had been released in the form of iodine – 131 and polonium – 210 had been released in the early stages as attempts were made to release heat through ventilation chimneys. Large areas were contaminated, food and milk bans were initiated and a massive cleanup was initiated. Major lessons were learned by the industry and the emergency response to nuclear incidents in the UK.
Three Mile Island
Sometimes the law of unforeseen consequences can throw up ironies that can only be appreciated decades afterwards. The event which had the most profound effect on the planet occurred at Three Mile Island (TMI) in Pennsylvania USA. Because of the incident, construction of nuclear power stations ceased virtually across the world. The irony is that the loss of nuclear power generation increased the used of fossil fuel generators with the consequential production of greenhouse gases. On March 28, 1979 a minor technical fault in a reactor led to a complex chain of events which resulted in the loss of water from a cooling circuit in the reactor. Fuel temperatures rose substantially and within hours one-third of the fuel had melted and large amounts of fission products were released into the reactor containment. Radioactive gases and a small quantity of iodine were then released into the atmosphere. During the course of the accident, authorities advised pregnant women and preschool children living within eight kilometres of the plant to leave and people living within 10 miles to remain indoors. The population within five miles of the plant was reported to number approximately 25,000 and mass panic ensued. Fortunately, because the release was almost all gaseous there was virtually no ground deposition and consequently no requirement for food restrictions or longer term measures.
As with the Windscale fire, there were a large number of detailed lessons learned. In overall terms, the most important lesson was the realisation that the public perception of a nuclear accident requires central government to be involved, and to be seen to be involved, and to provide facilities where the various agencies involved in emergency response can come together to make decisions about the off-site aspects of the emergency. This approach ultimately results in the preparation of off site emergency centres. A film, The China Syndrome, about a near disaster at a nuclear power plant, starring Jane Fonda and Michael Douglas had been released 12 days before the accident at Three Mile Island and this was believed to have helped contribute to some of the panic that ensued. ‘China syndrome’ refers to the way that a nuclear reactor that becomes uncontrollable will burn its way through the earth re-emerging in China (for UK installations it could be known as the ‘New Zealand syndrome’ – more of a mouthful!). One of the issues highlighted by the accident was the way information was given to the public. Local, state and federal agencies all attempted to provide information but in a disjointed fashion causing confusion and exacerbating the panic. Following TMI, a coordinated system for public information was developed. In the UK, as a direct result the Three Mile Island national plans for nuclear emergencies were implemented as were the first generation of offsite emergency facilities.
Chernobyl
In what was possibly the worse case scenario, on April 26, 1986 an explosion occurred at the Chernobyl nuclear power plant in the Soviet Union republic of Ukraine. The explosion blew off a reactor lid, exposing the burning core and releasing radionuclides to the atmosphere. Twenty-nine firefighters and plant workers lost their lives from exposure to the radiation that was contained in the firefighting water runoff.
As a direct result of the bravery of the firefighters, knowingly exposing themselves to a suicidal risk, the fires were extinguished but the radioactive release continued for over ten days. Because the incident was unprecedented standard operating procedures or organisational infrastructure to solve the problem of environmental contamination over such a large area existed. It is probably true to say that had an incident occurred in any less controlled nation, it is unlikely that the response to events would have been less single minded than that of the Soviet government. The recovery countermeasures eventually implemented were principally decontamination and restricted access to areas of high radioactive contamination which is still the case in many parts of the affected area. Contamination of large areas of the Russian Federation, Belarus and Ukraine had seriously affected the local population. Approximately 135,000 members of the public were evacuated from an exclusion zone at a radius of 30km around the site and many remain permanently relocated to this day. Widespread contamination in northern Europe led to restrictions on the sale and consumption of some foods even in the UK. The number of people affected by the Chernobyl accident remains uncertain.
Nuclear Suicide Bombers
The consequences of an incident at a nuclear installation is all too obvious but with the improving safety record of the nuclear industry does make the likelihood of a nuclear accident one that is receding despite the imminent increase in number of reactors. Similarly, the end of the ‘first Cold War’ has reduced the likelihood of an accident involving a nuclear facility has decreased. According to US Air Force documents, between 1950 and the late 1990s there were over 90 nuclear weapons accidents or ‘Broken Arrows’. Fortunately, most involved no loss of containment. The crash of a Korean Air Boeing 747 containing radioactive materials at Stansted in 2000 show that the potential for an accident is not confined just to the military. So much for accidental releases of radioactive materials. Now, one of the main concerns for the UK and other nations is the deliberate use of radioactive materials as a weapon of terror. Since September 11, 2001 emphasis in the nuclear and radiological field has tended to shift from that of accidental events or state sponsored attacks to those involving radiological terrorism. The threat of suicide bombers using nuclear devices had been considered as long ago as the 1950s.
Government papers released in 2004 make reference to the government being warned in 1950 of the possibility of Soviet troops using nuclear suicide bombs. Given the difficulties of making a nuclear weapon, the threat of an improvised nuclear device (IND) is fairly remote. Far more credible radiation scenarios exist that could be used by terrorists. These chiefly comprise an improvised radiological device (an IRD or ‘dirty bomb’); a radioactive emplaced device (a RED); and the contamination of food or water supplies with radiation. Despite the low likelihood of it happening, experts believe that with the right grade of uranium-235, an Improvised Nuclear Device (IND) could be made relatively easily. A device capable of delivering a yield of around 100-1,000 tonnes of TNT is theoretically possible.
The limited explosive effect would concentrate fallout to within a few kilometres of the epicentre. The clean up operation would probably be of little importance during the emergency phase of operations – the ‘fog of disaster’ – but in the longer term, a massive clean up and disposal operation would be necessary. In terms of response, in May 2001 the Centre for Strategic Studies estimated that in the event of an IND being exploded in the USA, FEMA and the Department of Defence would be ‘rapidly overwhelmed’. One can only assume that this would also be true in the UK. There is, however, the national resilience program that would be in place to ensure that there would be, at least in a short time, a measured response to an incident of this type.
The potential disruption and recovery from localised or site-specific radiological emplaced devices (RED) can be significant. A RED device could be a simple radiation source or a leaking source with the potential to contaminate the public and/or irradiate them. Given the disruption that was caused by the recent radiation scare in the aforementioned Edinburgh school, the impact of a deliberately placed RED would undoubtedly cause mass panic in the population due to the threat felt by communities. An IRD or dirty bomb has become the ‘bete noir’ of the terrorists’ arsenal with governments introducing measures such as a financial reward running to millions to repatriate nuclear fuel scattered around the globe. A dirty bomb is an explosive device used to disperse radiological materials. The idea is not new and such weapons were considered during the Second World War. Iraq has acknowledged to the UN that it explored the potential during its war with Iran. Chechnyan terrorists were alleged to have buried ‘but not to have detonated’ a 30-pound box of Caesium- 137 and dynamite in a busy Moscow park in 1995.
Such weapons could be made from, inter alia, depleted uranium or other low-grade nuclear materials. The contaminated area would be relatively limited and despite the wide-ranging impact of such an attack the clean up operations are likely to be smaller than (dependent upon the quantity and power of the explosive device) the non-nuclear detonation of a nuclear weapon.
Goiânia, Brazil
As an example of what the consequences of a deliberate release of materials could be, it is worth reviewing a notorious incident that occurred in Goiânia, Brazil in 1987. A teletherapy unit containing 23 grams of caesium-137 was stolen from a surgery for scrap metal. The thieves ruptured the container and spread contamination across the city. Four people died and 28 suffered radiation burns. Seven buildings were demolished and the decontamination of the environment took six months and generated some 3,500 m3 of radioactive waste. Over 240 people were severely contaminated, 112,000 were monitored and environmental monitoring was carried out over 67 sq km of the city. The effort involved in a Goiânia scale emergency in the UK would be enormous. Implications for a NRI in the UK with similar consequences are therefore significant in terms of resources and resilience. With the advent of the Government Decontamination Service (GDS), the resources necessary for this essential task will now be the responsibility of contractors but Fire and Rescue Service involvement is still likely to occur. For the UK fire and rescue services, has the risk of involvement in radiation incidents increased in recent years? The number of incidents occurring in the UK does not vary noticeably each year. The Litvinenko affair was, hopefully, a unique occurrence, which for logistical reasons is unlikely to be repeated.
As an example of what the consequences could be of other types of incidents, it has been a useful test of the national infrastructure to detect and mitigate the effects of radiation.
The increasing reliance on nuclear power to control global climate change may require the Fire and Rescue Service once again to review their responses to meet the needs of the community. |
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