NRC TO DISCUSS PSEG RESPONSE TO ‘YELLOW’ PERFORMANCE INDICATOR
AT SALEM UNIT 1 NUCLEAR POWER PLANT AT MEETING ON JAN. 21

Nuclear Regulatory Commission staff will meet with representatives of PSEG Nuclear, LLC, on Wednesday, Jan. 21, to discuss a “yellow” performance indicator experienced by the Salem 1 nuclear power plant in late 2007 over emergency AC power reliability/availability. The performance indicator returned to “green” in early 2008.

The meeting, which will be open to the public, is scheduled for 2 p.m. at the Salem County (N.J.) 911/Emergency Services Center, at 125 Cemetery Road in Woodstown, N.J. After the business portion of the meeting, and prior to adjournment, those in attendance will have an opportunity to communicate with the NRC staff regarding PSEG’s performance in this area. PSEG owns and operates Salem Units 1 and 2, as well as the adjoining Hope Creek nuclear power plant, all of which are located in Hancocks Bridge (Salem County), N.J.

Color-coded performance indicators and inspection findings are utilized by the NRC to evaluate nuclear power plant performance. The colors start with “green” and then increase to “white,” “yellow” or “red,” commensurate with the safety significance of the issues involved. In the case of the performance indicators, they are updated on a quarterly basis as new plant data becomes available, with any changes reflected on the NRC’s web site, at www.nrc.gov.

At the end of the fourth quarter of 2007, the performance indicator for emergency AC power for Salem Unit 1 changed from “green” to “yellow.”  The indicator involved – one of several mitigating systems performance indicators – measures the availability and reliability of a plant’s back-up power sources, including its emergency diesel generators. (Availability relates to a measure of how much time an emergency diesel generator is out of service due to equipment or other problems. Reliability relates to whether an emergency diesel generator will start upon demand.)  The Salem Unit 1 and Unit 2 reactors are each equipped with three emergency diesel generators that provide back-up power in the event of an off-site power loss to the plants. Any changes in this indicator are based on the sum of the unavailability and the unreliability of emergency AC power supplies during the previous 12 quarters.

During the 12 quarters prior to the end of 2007, there were three emergency AC power supply failures at Salem Unit 1. On Aug. 30, 2005, the 1C emergency diesel generator failed to run during testing, and on March 29, 2007, and Dec. 10, 2007, the 1A and 1C emergency diesel generators failed to start during testing, respectively. Although the primary contributor to the reported value related to the August 2005 equipment issue, the failure of the 1C generator to start in December 2007 led to the performance indicator crossing the established threshold and consequently changing from “green” to “yellow.”  The performance indicator changed back to “green” as of the end of the first quarter of 2008 when the back-up power data was updated.

As a result of the performance indicator color change, Salem Unit 1 moved during the fourth quarter of 2007 from the Licensee Response column of the NRC’s Action Matrix to the Degraded Cornerstone column. The Action Matrix, which is available at http://www.nrc.gov/NRR/OVERSIGHT/ASSESS/actionmatrix_summary.html, is used by the agency to determine the appropriate level of oversight for nuclear power plants. The change resulted in a corresponding increase in the NRC’s inspection and assessment oversight at Salem Unit 1 that included a supplemental inspection to provide assurance that the problem had been adequately addressed.

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Thursday, January 15, 2009