Should people install used parts in a nuclear power plant? Tokyo Electric Power Company (Tepco) did — at Fukushima Daiichi, the now-notorious nuclear plant that seems plagued with problems. The manager of Fukushima Number One admitted that the facility was using used parts in the construction of holding tanks currently being tasked to hold supplies of radioactive seawater at the site.
He assured the public that the used parts are thoroughly tested before being put into place and that a massive underground frozen wall will act as a sufficient failsafe, but not everyone is convinced about the safety measures at Fukushima — Dave Klein, former US Nuclear Regulatory Commission head, told The Guardian that Tepco needs “…more testing and more analysis” in a discussion of the frozen wall in July.
An inside source told The Mainichi Shimbun that “We don’t guarantee the tanks for five years as a company, and they are not made to be completely leak-proof in the first place.” The report goes on to note that “Multiple private investigation firms have said that the tank supplier reported high profits for June 2011 as the nuclear disaster created heavy demand for its water tanks and enabled it to sell off ‘depreciated’ tanks. The reference to the tanks as ‘depreciated’ is believed to indicate that a considerable amount of time had passed since their manufacturing date.”
The parts in question are metal plates used on flange-type storage tanks. Such tanks are actually already prone to leakage because of their construction, which includes a number of seams and bolts (in contrast with welded tanks). The manager says that all the sealing parts were new, and the used parts were checked carefully for any signs of loss of integrity before radioactive seawater was allowed to fill the tanks.
He can’t say how many tanks overall might include used parts, though. Given testimony from former and current workers in January this year about the slipshod nature of the storage tanks, which are assembled at a high rate due to a growing need, it’s entirely reasonable to ask questions about the safety of this storage method.
Last year, similar flange-type tanks actually sprung leaks, although they included entirely new parts. This illustrates that this method of construction may not be entirely optimal for the safe storage of nuclear material. This may be in part due to the inherent weaknesses of a tank design that includes multiple joints, all of which create vulnerabilities for leaks. There’s also concern that corrosive seawater could be wearing tanks more quickly than expected, or that the radiation could be having some effect on the integrity of the metal. Whatever’s happening at Fukushima Daiichi, it represents yet another possibility for a release of nuclear material into the environment, and that’s bad news.
According to The Japan Times, the facility is replacing flange-type tanks with welded models in the hopes of reducing the risk of leaks, recognizing the problems with the old design. However, the use of used parts should be cause for concern. What kinds of regulatory systems do Tepco and the Japanese government have in place to govern the application of used parts in nuclear plants? How are these systems enforced, and what is the testing standard for used parts in storage tanks and other nuclear components?
The lack of clear public disclosure on these subjects is troubling in light of the revelation that plant operators purchased used components, but aren’t sure how many were used. The public deserves to know, as there’s not necessarily anything wrong with using high-quality refurbished components, if there’s a system to test their integrity, monitor them and retire them at the end of their natural lifetime. Furthermore, this is clearly a subject that government regulators need to be informed about, so inspectors can act accordingly at nuclear plants. This issue is one that affects the globe, not just Fukushima or even just Japan, due to the risk that uncontrolled radiation could spread.
It’s also an issue of larger concern for both sides of the nuclear energy debate. Those arguing that nuclear energy is clean and safe point out that what happened at Fukushima was the result of a catastrophic series of regulatory and inspection errors that compounded to create a nightmare. Those opposed to nuclear energy, though, ask whether it can ever be truly safe, especially since many nuclear plants around the world are facing similar infrastructure problems.
Fukishima wasn’t an exception: It was a warning, and it was a costly one for the thousands of people affected, and for the generations who will continue to live with the aftermath of the nuclear accident and the damage it wrought on communities and the landscape.
Photo credit: Nuclear Regulatory Commission.