Warning signals
PRAFUL BIDWAI| As the global nuclear industry's fate hangs in the balance, India must rethink its nuclear power expansion plans and impose a moratorium on new reactors. "We cannot afford another accident." This was the categorical comment of Mohamed ElBaradei, then the International Atomic Energy Agency (IAEA) Director-General, on a nuclear mishap at a seven-reactor plant at Kashiwazaki-Kariwa, the world's largest nuclear power station, that released 1,200 litres of radioactive water following an earthquake in Japan in July 2007. The operator of the plant was Tokyo Electric Power Company (Tepco), which also runs the Fukushima reactors that have just had a huge loss-of-coolant accident (LOCA) following the March 11 earthquake and tsunami in Japan. ElBaradei said: "It's clear that this earthquake, as Tepco … indicated, was stronger than what the reactor was designed for." The Fukushima reactors are older than those at Kashiwazaki-Kariwa and probably more under-designed. Tepco lied about the 2007 accident by claiming that there had been no radioactivity release. Investigators found that it had unknowingly built the plant on top of an active seismic fault. Tepco has now plunged the global nuclear industry into its worst crisis since the Chernobyl disaster, whose 25th anniversary falls on April 26. Although the three reactors at the Fukushima Daiichi nuclear station have not had a core meltdown at the time of writing, in some ways the crisis is even more severe than the Chernobyl catastrophe. Chernobyl was attributed to a flawed reactor design and sloppy operating practices in industrially backward Ukraine. Fukushima cannot be so attributed. Japan's nuclear safety standards are supposedly the best in the global nuclear industry. The accident that the industry "cannot afford" has probably happened. The industry's fate now hangs precariously in the balance in Japan. If the Fukushima reactors' cores cannot be rapidly cooled and if a large radioactivity release occurs, with or without a complete core meltdown, the industry's days may well be numbered. It is already suffering from stagnation and decline: world nuclear power generation peaked in 2006/07 and is falling, as is the number of operating reactors. The United States' nuclear industry, which has received no new reactor order since 1973, has not recovered from Three Mile Island (1979). Nor has the European industry overcome the blow delivered by the Chernobyl incident. The "nuclear renaissance" announced by George W. Bush always looked wobbly, with poor economics and a bad "learning curve": the industry takes almost twice as long to build a reactor now as it did in the 1960s and 1970s. Now, the "renaissance" will probably be terminated as the industry enters a new phase of crisis. What exactly happened in Japan over the fateful weekend of March 12-13? In the absence of complete information, which neither Tepco nor the Japanese nuclear regulatory agency has parted with, it is hard to reconstruct the precise sequence. But going by analyses by the U.S.-based Union of Concerned Scientists (UCS), and other independent experts, the earthquake shut down the three operating reactors at Fukushima, as designed, thereby cutting off the power with which to cool the reactors' still-hot cores and control rods. As designed, the back-up diesel generators cut in, but an hour later, cut out, for as-yet-unknown reasons. The core, containing hundreds of tonnes of fuel, started heating up further. As water circulation stopped, more than half the core was exposed in Reactors 3 and 1. It was fully exposed in Reactor 2, which is also in distress now. The three reactors all suffered a LOCA, which carries the hazard of a partial or complete core meltdown. On March 12, an explosion occurred in the Reactor 1 building, probably caused by accumulated hydrogen. The hydrogen was probably produced by the hot fuel. The detection of significant quantities of caesium-137 outside the reactors suggests that the fuel was damaged. Caesium-137 is a product of the splitting or fissioning of uranium atoms, as is iodine-131. Tepco claims that neither the Reactor 1 vessel nor its primary containment, a steel vessel surrounded by a reinforced concrete shell, was breached. The claim is hard to verify. But the concrete shell could well have been damaged by the two explosions. It is also not known whether the control room and the power cables needed for the emergency equipment used to cool the reactor core, which are located outside the primary containment, were damaged. At any rate, unspecified quantities of radiation were released. Radiation from Daiichi was detected by a helicopter 100 kilometres away. Of particular significance are iodine-131 (which gets concentrated in the thyroid, leading to cancer) and caesium-137 (which is similar to potassium in its chemical properties and gets easily absorbed in human tissues). These releases have grave health implications. Caesium-137's half-life is about 30 years, which means it will take a century to decay significantly. To cool the reactors' cores, Tepco has been pumping seawater into them with fire-pumps against high pressure. This is an option of last resort and will mean writing off the reactors. Tepco has also been venting contaminated steam and other radioactive vapours from time to time to release high pressure, thus adding to the harm to the public. To sum up, the Daiichi reactors suffered LOCAs and may yet undergo a core meltdown with catastrophic radiation releases. There is clinching evidence of reactor core/fuel damage from Reactor 1. All three reactors have had explosions. The situation is not under control despite desperate measures. There are other apprehensions too. Two are important. There are reports that large quantities of spent-fuel rods are stored in the Reactor 1 building in keeping with the General Electric Mark I design. They pose a great hazard because of the site's flooding under the tsunami. These rods contain tonnes of high-level radioactive waste. Secondly, Reactor 3 uses mixed uranium-plutonium oxide (MOX) fuel in the core. According to Edwin Lyman of the UCS, "the use of MOX generally increases the consequences of severe accidents in which large amounts of radioactive gas and aerosol are released compared to the same accident in a reactor using non-MOX fuel…. Because of this, the number of latent cancer fatalities resulting from an accident could increase by as much as a factor of five for a full core of MOX fuel compared to the same accident with no MOX." General Electric's Mark I design, it emerges, is unusually vulnerable to containment failure in the event of a core meltdown. A recent study by Sandia National Laboratories shows that the likelihood of containment failure is nearly 42 per cent. "The most likely failure scenario involves the molten fuel burning through the reactor vessel, spilling onto the containment floor, and spreading until it contracts and breaches the steel containment-vessel wall. The Sandia National Laboratories report characterises these probabilities as 'quite high'." The crisis in Japan proves what might be called the nuclear version of Murphy's Law: all that can go wrong will go wrong at some point in a nuclear reactor. Japan is a technologically advanced country, and its safety standards are among the world nuclear industry's highest. This Fukushima crisis shows that all reactors are vulnerable to the risk of catastrophic accidents irrespective of precautions and safety measures. The Japan crisis holds a number of lessons for India as it embarks on a massive nuclear power expansion programme, which will double and then further triple India's nuclear capacity. First, nuclear power generation is inherently hazardous. It is the only form of energy generation that can lead to a catastrophic accident with horrifying long-time consequences in health damage and environmental contamination. Human error or a natural calamity can trigger a catastrophic accident – but only because reactors are themselves vulnerable. Reactors are high-pressure high-temperature systems in which a high-energy fission chain reaction is only barely controlled. In organisation theory terms, discussed ably by Charles Perrow in his classic Normal Accidents, nuclear reactors are both systemically complex and internally tightly coupled. A fault or malfunction in one subsystem is quickly transmitted to other subsystems and gets magnified until the whole system goes into crisis mode, often in seconds or minutes. Second, nuclear power involves radiation exposure at all stages of the so-called "nuclear fuel cycle", from uranium mining and fuel fabrication, to reactor operation and maintenance, to routine emissions, to spent-fuel handling, storage and reprocessing. As this column has discussed earlier, reactors leave a toxic trail of high-level radioactive wastes. These remain hazardous for thousands of years. The half-life of plutonium-239, produced by fission, is 24,000 years. Science has no way of safely storing nuclear wastes for such long periods, let alone neutralising them or disposing of them. Third, these risks are turning out to be unacceptable. They can only be remedied at a high expense, which would make nuclear power even more exorbitantly expensive than it already is. Fourth, while the industry claims nuclear power is safe, it expends a considerable effort in lobbying for laws that limit the operator's or supplier's liability for accidents to artificially low levels. The objections raised by the U.S. and France to India's recently passed Nuclear Liability Bill, despite the artificially low limit placed on liability at a few hundred million dollars, signify that the industry acknowledges that nuclear power carries high risks of damage but wants governments – that is, the public – to subsidise and absorb them. Fifth, India has no independent authority that can evolve safety standards and regulate reactors for safety. The Atomic Energy Regulatory Board (AERB) is not such an authority. It is dependent for its budget, equipment and personnel on the Department of Atomic Energy (DAE) and reports to the Chairman of the Atomic Energy Commission (AEC), who is also the DAE's Secretary. Over the four decades and more since the Tarapur reactors were installed, the DAE has merely implemented or copied U.S. and Canadian designs, with minimum modifications. It has shown no ability to improve substantially on existing safety designs, leave alone innovating new ones. Sixth, the Tarapur reactors are based on General Electric's (GE) Boiling Water Reactor (BWR) design, similar to the Fukushima reactors, only older, smaller, and possibly with less advanced safety systems. This, coupled with Sandia National Laboratories' conclusion that its primary containment is fragile, demands a thorough analysis in collaboration with other operators of GE reactors, including Tepco. Meanwhile, it would be prudent to shut down the two Tarapur reactors, which are more than 40 years old and badly contaminated. Seventh, India must rethink its plans to expand nuclear power generation by importing French, Russian and U.S. reactors, including the untested design of the French company Areva's European Pressurised Reactors (EPRs), six of which are to be installed at Jaitapur in Maharashtra. These contracts are being given away to foreign companies, without even the pretence of competitive bidding or techno-economic evaluation, as a means of rewarding them for the role their governments and business lobbies played in the completion of the India-U.S. nuclear cooperation deal and its endorsement by the IAEA and the Nuclear Suppliers Group (NSG). These reactors, including the proposed AP-1000 designed by Westinghouse in the U.S., have not passed the approval barrier in any country with a reasonably independent regulatory authority. Their designs have not yet been frozen and their hazards are not fully understood. Besides, their capital costs are far, far higher than those of indigenous reactors, which themselves produce power that is about twice as expensive as electricity from conventional sources, and some renewable sources too. Finally, it would be a grave blunder for India to seek energy security through the nuclear route. The route is bound up with unacceptable hazards and long-term legacies of decommissioning nuclear reactors (which can cost one-third to one-half as much as constructing new ones) and waste storage over centuries. As energy planners such as A.K.N. Reddy have convincingly shown, India's energy needs would be best met by a thoughtful combination of conservation; local decentralised systems, including biomass, solar-thermal and wind; and a measure of conventional sources. Besides, there is a huge potential for solar photovoltaics and micro- and mini-hydroelectricity, which has not been tapped. If, as analysts argue, it is possible even for the U.S. to have a low-carbon, non-nuclear future, why should that not be so for India? After the Japan crisis, the issue of nuclear safety has become paramount. It must take precedence over all else. It would be downright unethical to sacrifice safety in order to appease an industry that has failed the world or to please the technocratic nuclear elite that considers itself infallible, omniscient and above the public interest. Japan's greatest lesson is that human societies and institutions must not become slaves to the nuclear industry. |
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