A year ago, a catastrophic chain of events was triggered by a powerful magnitude 9 earthquake centred under the seabed about 100 kilometres off the north east coast of Japan. Travelling left and right of the ruptured fault, two wide and high water fronts moved in opposite directions. The eastbound tsunami produced moderate 1-2 metre surges at the coasts of Canada, western US, and Chile as its energy dissipated over the several thousand kilometre journey. Still, millions of dollars of damage was reported to boats, jetties and so on.
The westbound water mass covered the 100 kilometres distance to the Japanese coast in about an hour. As it reached shallow land, the tsunami slowed to 30km an hour and seaside residents had 10 minutes warning of an approaching wall of water ranging from 5-15 metres in height, sufficient to breach the sea wall that protects about 40 per cent of the Japanese eastern coastline.
In places, the surge of water extended 10 kilometres inland. Twenty thousand people died or are unaccounted for. More than 90 per cent of the victims drowned. The lives of 5 million Japanese were directly impacted. The reconstruction bill will exceed $250 billion, making this the most costly natural disaster in history.
At the Fukushima nuclear plant, the three operating reactors shut down as accelerometers detected the shaking of the earth. Three other reactors were offline, undergoing routine maintenance or refuelling. But the arrival of the tsunami flooded the site to a depth of 5 metres and knocked out all power – a catastrophic situation where even spent fuel rods in storage require electricity to continuously circulate cooling water for years. Nuclear cores melted, hydrogen gas explosions breached containment buildings, and uncontrolled releases of radiation were sufficiently great that Fukushima is now rated second only to Chernobyl in severity as a nuclear accident.
A year later, the clean-up task at Fukushima is well underway. Three thousand workers are carefully dismantling the site where all six reactors were irretrievably damaged by the tsunami that washed over the Japanese plant.
This decommissioning process, typically taking up to 40 years for reactors which have reached their use-by date, will include eventually removing several centimetres of topsoil contaminated with radioactive caesium from across the site. There is no reliable figure available but the replacement cost of six reactors, decommissioning and site remediation could amount to $50 billion – even before the cost to the national economy of imported fuels to offset the loss of nuclear electricity generation is included.
Investigations continue to better understand this nuclear accident. A number of findings have emerged and mitigation strategies are being recommended and adopted.
– The requirement to have capable, independent and active regulators of a nation’s nuclear system has been emphasised, as has the need for rigorous licensing and relicensing procedures for reactors that can operate for 60 years or more.
– Reactor operators around the world and nuclear safety agencies have been required to complete stress testing and make changes to ensure safety in extreme circumstances, including scenarios where multiple hazards occur contemporaneously. (In some ways, this is analogous to the current work of the world’s financial regulators in stress testing banks and other financial institutions and increasing safety margins through mandated strengthening of capital adequacy ratios.)
– More rigorous evaluation of power plant sites has been demanded, especially in areas with a history of natural hazards, and criteria developed for better designs to reduce risk from earthquakes, hurricanes and tsunamis. Interestingly, Japan’s near neighbour South Korea has an active geology and 21 largely coast based reactors producing 30 per cent of its electricity. Following careful review, that country has confirmed its plan to increase its nuclear network to 40 units by 2030 to produce nearly 60 per cent of its electricity demand. South Korean reactors are increasingly finding a world market for their designs.
– Additional onsite portable equipment will be required. This includes diesel driven pumps and electric generators to provide power and water to three key functions: reactor core cooling, used fuel pool cooling, and containment integrity. The locations would be diverse, protected and accessible when other safety systems are compromised. (In the US, such steps were taken following the 9/11 terrorist attacks to help facilities respond to large fires and explosions.)
– Improved and hardened vents are to be installed, to maintain containment but also to enable gas pressure to be relieved even when the reactor control room is disabled and cannot function. Appropriate venting of hydrogen would avoid explosions that release radioactive material to the environment.
– Instrumentation is to be upgraded to provide remote monitoring of the condition of storage pools and to coordinate responses especially for multi event/ multiple site emergencies. Some reactors from the 60s and 70s operate with analogue controls and are a generation behind modern wireless communications.
– A cooperative international emergency response framework is being developed to assist in the expeditious deployment of experts and resources should another nuclear accident occur. In the aftermath of Fukushima, crisis management processes are being upgraded.
One difficult issue refers to the social consequences connected with the evacuations around the Fukushima site. A total 100,000 people remain displaced, awaiting permission to return to their homes within the 20 kilometre exclusion zone. The Japanese government quite reasonably aims to limit radiation exposure of evacuees returning home but struggles to balance this against the major health and welfare impact of ongoing displacement.
Exaggerated fears about radiation should not add to hardship by unnecessarily preventing people from returning home to resume normal lives. The long-term social impact of this nuclear disaster won't be measured by the number of radiation caused sicknesses – there are likely to be very few if any – but by the anxiety, depression and other mental illnesses affecting people obsessing about potential consequences of any radiation exposure. Fear of ionizing radiation could have long-term psychological effects on a large portion of the population in the contaminated areas. This certainly is the experience from Chernobyl.
In Australia, at some distance from these dramas, interesting progress has been made at the nuclear front during this past year. New South Wales has joined with South Australia, the Northern Territory and Western Australia in allowing exploration for uranium, although it has stopped short of permitting commercial development of any resource. This is still a small step and undoubtedly watched by Queensland, a state believed to be prospective for that mineral.
The Australian Labor Party has adopted a policy to add India to its list of approved countries for Australian uranium exports. Given India’s commitment to nuclear energy – it has twenty reactors currently operational and six under construction, with a target of sixty by 2030 – and its good non-proliferation record, this decision was long overdue.
Having fallen to fourth place as a uranium exporter, but with nearly 40 per cent of the world’s uranium, Australia awaits the decision of BHP Billiton to invest nearly $50 billion in its Olympic Dam expansion. This investment, for which uranium is a small economic driver behind copper and gold, could see Australia become the world’s largest producer of uranium in the 2020s.
The government has introduced a carbon tax, a pathway to an emissions trading system in 2015 and greenhouse gas emissions reduction targets. Its draft Energy White Paper describes a ‘clean energy future’ but without nuclear power. For this reason, I consider it is unrealistic even if many elements therein are sensible. Still, its authors acknowledge that should renewables fall short of expectations – technically or costwise – nuclear power must be considered for Australia. I reckon this debate will unfold well before 2020.
Progress has been made to permit construction of a national repository in central Australia for low-level nuclear waste – such as waste from nuclear medicine treatments, university research labs and industrial radioactive sources. This simple step (low-level waste is uncomplicated stuff) has been made difficult by disinformation campaigns raising exaggerated concerns about possible community exposure to radiation. Given bipartisan support, legislation is expected to pass this year.
And the state-of-the-art OPAL research reactor at Lucas Heights, which achieved steady state operation in 2009, continues to produce radioisotopes for nuclear medicine diagnosis and treatment, high quality neutron-based research and innovative nuclear techniques in support of our resources industry. Along with the Melbourne-based Synchrotron, Australia has world class reactor and accelerator facilities, with great atomic scientists doing excellent work.
Finally, the issue of nuclear submarines has surfaced (pun intended). Given their superior technical performance at similar costs, the decision to acquire nuclear propulsion seems self-evident, especially as the reactor core is designed as a drop in module replaced, battery like, every two decades or so.
The disaster at Fukushima certainly set back support for nuclear energy, at least in the West, albeit temporarily. But as more people have engaged with the nuclear option and had their tough questions answered, the case for nuclear energy has been strengthened. Certainly, no country in the world provides a better fit for nuclear – in a technological, geologic and regulatory sense. We just need confident and farsighted Australian leadership to pave the way.
Ziggy Switkowski is the chancellor of RMIT University and former chair of the Australian Nuclear Science and Technology Organisation.