"Any time you start tolerating minor problems, you're just setting the stage for major safety problems down the road," said nuclear engineer David Lochbaum of the Union of Concerned Scientists. He once trained NRC staff.
Phillip Musegaas, a lawyer with the environmental group Riverkeeper, said regulators should do more to make sure that lower-level violations are fixed. "NRC's tracking to make sure these violations are resolved is completely ineffectual," he said.
In its official response to the report, the NRC defended the objectivity of its plant assessments. At the same time, it acknowledged the regional differences and promised to look deeper into why they happen.
According to the GAO, the NRC regulatory staff also offered several explanations, including regional variations in reactor ages and time spent on inspections. However, the congressional watchdog said those explanations are not supported by the data.
The agency did offer that regulators may be right when they cite the possible impact of joint ownership of sites, a circumstance most prevalent in the Southeast. Nuclear plants under one owner may benefit from more corporate resources and thus avoid violations, the GAO suggested. The NRC also said higher-level violations are more consistent because they are more deeply reviewed.
On other issues, the report said the NRC needs an easier-to-use internal database to help staff learn of historical safety issues that apply to current problems. It also pressed the agency to improve its public documents website to allow tracking of safety violations. The NRC said it would work to improve both tools.
Senators requested the report in reaction to the Japanese nuclear accident at Fukushima in 2011 and an Associated Press investigative series later that year about aging U.S. nuclear plants. The AP series found that federal regulators had relaxed safety rules to keep plants running beyond their initial licenses. It also reported leaks of radioactive tritium at three-quarters of plants and outdated estimates of evacuation times.
The GAO analyzed data for 104 commercial reactors, but four permanently shut earlier this year: Crystal River in Florida, Kewaunee, and the two units at San Onofre in California.
The AP National Investigative Team can be reached at email@example.com
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