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NRC NEWS U. S. NUCLEAR REGULATORY COMMISSION OFFICE OF PUBLIC AFFAIRS, REGION I 475 Allendale Road, King of Prussia, Pa. 19406

NRC CITES CONSOLIDATED EDISON FOR VIOLATION AT INDIAN POINT 2

The Nuclear Regulatory Commission staff has cited Consolidated Edison Company of New York for a violation of NRC requirements for steam generator tube inspections at its Indian Point 2 nuclear power plant in Buchanan, N.Y. The plant experienced a steam generator tube failure in February 2000. While there were no public health and safety consequences from the February 2000 steam generator tube failure, which brought this violation to light, the NRC has determined that the conditions associated with the violation were of high safety significance.

In its report issued in late August, an NRC inspection team preliminarily concluded that the overall direction and execution of Consolidated Edison's 1997 steam generator inspections at Indian Point 2 were deficient in several respects. Those deficiencies resulted in the company's failure to adequately account for conditions which adversely affected the detectability of, and created increased susceptibility to, steam generator tube flaws. The team concluded these failures resulted in tubes with flaws being left in service following the 1997 inspection, until one of these tubes failed in February. While the event did not adversely impact public health and safety, leaving the degraded tube in service following the 1997 steam generator inspections resulted in a significant reduction in safety margin during the plant's operating cycle, based on the increased probability of a steam generator tube rupture.

The August NRC inspection report preliminarily characterized the findings as "red" and offered the company an opportunity to attend a regulatory conference with the NRC staff. During a September 26 regulatory conference, Con Ed staff discussed an analysis of the probability of tube rupture, its assessment of the significance of the issue and measures to prevent a recurrence. Based on the NRC's evaluation of this information, the NRC has lowered its calculation of the risk estimate in this case. However, the NRC's revised risk estimate remained above the threshold for classifying this finding as "red," an issue of high safety significance.

Under the NRC's revised reactor oversight process, the agency assesses inspection findings and characterizes their risk significance by color, specifically green, white, yellow or red. A green finding results in normal NRC oversight, while white, yellow or red assessments are considered progressively more serious and receive commensurately greater oversight.

Although Con Ed's risk analysis characterized this issue as a "yellow" finding, in a letter to Con Ed, NRC Region I Administrator, Hubert J. Miller, said, "The NRC recognizes that there is a wide band of uncertainty involved in such risk calculations and additional extensive review could possibly remove some of those uncertainties. Our risk estimate, which classifies the finding as red, does include a sensitivity analysis that for certain assumptions shows a range of results at the yellow/red threshold." As noted in an October 10^th letter to the company, Indian Point 2 has been found to have multiple degraded cornerstones. In response to the deficiencies at Indian Point 2, the staff is following guidance in the NRC Action Matrix, which includes oversight of Con Ed's performance improvement plan and conduct of a significant team inspection.

Con Ed has 10 days to appeal the staff's determination and must respond to the notice of violation within 30 days.

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