OAK HARBOR, Ohio — A southern California utility’s decision to decommission a nuclear power plant plagued by trouble with its replacement steam generators reinforces the need for deep scrutiny of proposed steam-generator replacement at the Davis-Besse plant near Toledo, an anti-nuclear activist coalition contends. Southern California Edison said Friday it will abandon plans to restart its twin reactors at San Onofre after investigation of a small radioactive-steam leak 17 months ago revealed extensive damage to hundreds of tubes that carry radioactive water in the plant’s virtually new steam generators.
The local coalition of Beyond Nuclear, Don’t Waste Michigan, Citizen Environmental Alliance of Southwestern Ontario, and the Sierra Club issued a statement saying the San Onofre debacle highlights the need for a full license-amendment process, including public hearings, for the generator replacements at Davis-Besse in Ottawa County, north of Oak Harbor.
FirstEnergy Nuclear Operating Co. should have applied to amend its license six years ago when it designed and ordered the replacement generators, said Arnie Gunderson, chief engineer at Fairewinds Associates Inc., who is consulting for the anti-nuclear groups.
As with the San Onofre generators, he said, there are “experimental” differences in materials and design between Davis-Besse’s equipment and the replacements.
“The steam-generator disaster at San Onofre and the public attempt to avoid similar bungling at Davis-Besse stem directly from the NRC’s [Nuclear Regulatory Commission’s] 24-year campaign to deregulate the industry,” said Terry Lodge, an attorney for the local coalition.
“At San Onofre and Davis-Besse, the NRC relied on the utility’s self-report as to whether there is anything significant about this very major feat of building and installing technologically different pieces of equipment,” Mr. Lodge said. “There has been a fiasco in three out of the last three steam-generator replacements. ‘Cross-my-heart-and-hope-to-die’ regulation is totally unacceptable.”
The groups’ statement said they were notified May 29 that the Atomic Safety and Licensing Board has seated a panel of judges to review their petition to intervene in the NRC process to approve the steam-generator replacement at Davis-Besse.
Jennifer Young, a FirstEnergy spokesman, said after the groups announced their position earlier last month that the utility’s “rigorous engineering and evaluation process” for any plant modifications is “closely reviewed by the Nuclear Regulatory Commission.”
“Protecting the health and safety of the public is the top priority of FirstEnergy Nuclear Operating Co. and the Davis-Besse Nuclear Power Station,” she said.
San Onofre’s problems centered on four new, much-heavier steam generators that were installed in 2009 and 2010 at a cost of $670 million. Later tests found some generator tubes so badly eroded that they could fail and possibly release radiation, a startling finding for nearly new equipment.
Each of the San Onofre generators has 9,727 alloy tubes, which function somewhat like a radiator. The tubes circulate hot, radioactive water, which then heats a bath of nonradioactive water surrounding them. That makes steam, which drives turbines to generate electricity. The leak early last year occurred in one of the tubes.
Federal investigators later concluded a botched computer analysis resulted in design flaws that were largely to blame for heavy tube wear.
Edwin Lyman, a nuclear expert at the Union of Concerned Scientists, a watchdog group, said the mistake raises broad questions for an industry that regularly relies on computer tools.
“That has larger importance, especially for new reactors,” Mr. Lyman said.
Mitsubishi Nuclear Energy Systems, which built San Onofre’s steam generators, said it is disappointed with the decision and remains confident the plant can be operated safely.
Source: The Toledo Blade