Two aging nuclear reactors will be allowed to operate beyond the 40-year rule -- adopted after the outbreak of the Fukushima nuclear disaster to limit the number of years a nuclear reactor can remain in operation -- the Nuclear Regulation Authority (NRA) announced June 20, setting a precedent that may turn the rule into a dead letter.
The NRA extended the 40-year operational life of the No. 1 and 2 reactors at Kansai Electric Power Co.'s Takahama Nuclear Power Plant by 20 years, with NRA chairman Shunichi Tanaka telling a June 20 news conference that "it is not the case that nuclear reactors were built to have a 40-year lifespan." This is an about-face from the NRA's first days in 2012, when Tanaka stated that "extending the operation (of nuclear reactors) is considerably difficult."
When the 40-year rule was introduced, the then Democratic Party of Japan administration said that any extension would be "an extreme exception." To gain approval for an extension, a reactor operator would have to obtain NRA approval for a work plan to bring the aging reactors in question up to new safety standards, and then obtain three more separate approvals. The Takahama No. 1 and 2 units in particular faced possible decommissioning if Kansai Electric hadn't submitted an operational life extension application by the July 7 deadline.
From the moment the application hit the NRA's desk, the agency effectively set out on a mission to save the Takahama reactors. To quicken the pace of the necessary inspections, the NRA concentrated its personnel at the two units. Furthermore, the NRA put off the usual inspections of the reactors' primary cooling systems -- a process that can take years -- helping Kansai Electric avoid the decommissioning deadline.
Even if the inspections hadn't gone well after the cooling system check was delayed, approval of the operational life extension wouldn't be cancelled. Within the NRA, there were voices warning that the agency would "lose the public's trust if we have to redo inspections."
The Takahama No. 1 and 2 units have a grand total of about 1,300 kilometers of cables in them, and the NRA even helped Kansai Electric get past the need to make them totally fire-proof. Replacing the cables would have been expensive and time-consuming, and so the NRA approved the utility's method of wrapping the old cables in fireproof material where they were difficult to change out. There are four other reactors in Japan with old cables similar to the ones at Takahama, and the NRA has just given their operators a "Takahama method" to obtain official approval.
There was a risk that Kansai Electric would have filed suit against the NRA if the agency had insisted on holding to the government's 40-year operational life rule and ordered the Takahama No. 1 and 2 reactors decommissioned. For Kansai Electric's part, the Takahama approval creates a model for receiving an extended life for another of its elderly reactors, at the Mihama Nuclear Power Plant. It also creates an environment where other companies will be able to gain easy approval for their own older units.