nuclear-news

Environmental groups urge regulators to shut down California reactor over safety, testing concerns.

Daily Mail, By ASSOCIATED PRESS, 15 September 2023

LOS ANGELES (AP) – Environmental groups called on federal regulators Thursday to immediately shut down one of two reactors at California´s last nuclear power plant until tests can be conducted on critical machinery they believe could fail and cause a catastrophe.

Friends of the Earth and Mothers for Peace said in a petition filed with the Nuclear Regulatory Commission that tests and inspections have been delayed for nearly 20 years on the pressure vessel in the Unit 1 reactor at the Diablo Canyon Nuclear Power Plant, midway between Los Angeles and San Francisco.

Instead, the groups argue, operator Pacific Gas & Electric has relied on data from similar reactor vessels to justify continued operations at Diablo Canyon, while dismissing indications that the steel wall in Unit 1 might be deteriorating from sustained exposure to radiation and is becoming susceptible to cracking, a condition technically known as embrittlement.

“We will not sit idly by while PG&E cuts corners on Unit 1´s safety,” Hallie Templeton, legal director for Friends of the Earth, said in a statement.

The vessels are thick steel containers that hold nuclear fuel and cooling water in the reactors.

The statement from the anti-nuclear groups contended that PG&E “has repeatedly postponed essential metallurgical tests and ultrasound inspections over the past two decades” on the vessel…………………………………..

The petition, filed Thursday in Washington, was accompanied by a 46-page report by Digby Macdonald, a University of California, Berkeley, professor in nuclear engineering and materials science, who wrote that continued operation of the Unit 1 reactor “poses an unreasonable risk to public health and safety due to serious indications of an unacceptable degree of embrittlement.”

“The reactor should be closed until PG&E obtains and analyzes additional data regarding its condition,” wrote Macdonald, who was retained by the environmental groups.

The petition asks the NRC to convene a hearing to review a 2003 decision by agency staff to extend the testing schedule for the Unit 1 pressure vessel until 2025. According to the groups, the last inspections on the vessel took place between 2003 and 2005. The utility postponed further testing in favor of using results from similar reactors to justify continued operations, they said.

In his report, Macdonald concludes PG&E should have accelerated its testing schedule, not delayed it, to assess possible defects. He noted that unlike most other reactor safety components, the pressure vessel has no independent backup system that can be called upon if it should crack or fracture and lose essential cooling water.

He added that obtaining more testing data on Unit 1 is especially important because its steel has excessive copper and nickel content “that render it more vulnerable to embrittlement.”

The “NRC currently lacks an adequate basis to conclude that Diablo Canyon Unit 1 can be operated safely,” Macdonald said.

Construction at Diablo Canyon began in the 1960s. Critics have long argued that potential shaking from nearby earthquake faults not recognized when the design was approved could damage equipment and release radiation. One nearby fault was not discovered until 2008. The groups argue that the embrittlement assessment is even more critical, given the plant’s seismic vulnerabilities…………  https://www.dailymail.co.uk/wires/ap/article-12519587/Environmental-groups-urge-regulators-shut-California-reactor-safety-testing-concerns.html

September 16, 2023 - Posted by Christina Macpherson | safety, USA