An investigation by The Associated Press found that regulators with the U.S. Nuclear Regulatory Commission (NRC) have been weakening standards so aging U.S. nuclear reactors could still be compliant with operating requirements.
The NRC has reportedly made decisions that original regulations were too strict and that safety measures could be eased without any danger, the news report said. The NRC continues to extend license renewals even as leaky valves, broken nozzles, failed cables and other issues have been discovered in several reports released by the commission.
Records reportedly show that as reactor parts or systems fell out of compliance, studies were conducted and found that existing rules were deemed “too conservative.” Regulations were loosened allowing reactors to be back in compliance, the report said.
Out of the 104 nuclear reactors in the U.S., 66 have been relicensed for 20 additional years and 16 others are currently under review, the AP report said. U.S. nuclear reactors were designed to run for 40 years and be replaced with newer models in that time frame. As of today, 82 reactors are more than 25 years old and getting older.
The AP report looked at pressurized water reactors and boiling water reactors over the past 40 years. The NRC issued 226 preliminary notifications since 2005, which are alerts on emerging safety problems, the AP said. Since 2005, at least 26 alerts reportedly have been caused by clogged lines, cracked parts, leaky seals, rust and other deterioration. The AP called the process “sharpening the pencil,” where calculations and assumptions are altered to yield answers that allow plants with deteriorating conditions to remain in compliance and continue operations.
According to the article, one 2008 report said 70 percent of potentially serious safety problems were caused by “degraded conditions,” many of which are caused by equipment wear. Also, inspections and repairs have been delayed for months until scheduled refueling outages, the report said. In 1995, a study by Oak Ridge National Laboratory found that over a seven-year period, aging contributed to 19 percent of scenarios that could have ended in severe accidents.
The NRC responded to the report, saying that while the commission disagreed with many of the observations and conclusions, it welcomes the attention the article brings to nuclear safety and security.
"The NRC takes as much time as necessary, in some cases years, to ensure requirements are met," the statement said.
The commission also said that through its own inspections, many plants have actually improved operations.
"The AP article fails to recognize that the NRC's own inspection and maintenance requirements have led plants to detect and repair, replace or otherwise fix the equipment, systems or other issues that were described in the article and in other instances which were not highlighted," the statement said. As an example, the NRC said inspections at the Fort Calhoun nuclear power plant in Nebraska showed the plant needed to correct deficiencies in its flood response plan. After NRC oversight, Fort Calhoun is now capable of riding out the current Missouri River flooding.
To read the entire statement from the NRC, click here.
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