Part 21 Report - 1997-730

ACCESSION #: 9710030170 COOPER NUCLEAR STATION P.O. BOX 98, BROWNVILLE, NEBRASKA 68321 TELEPHONE (402)825-3811 Nebraska Public Power District FAX (402)82--5211 NLS970124 September 29, 1997 U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555-0001 Gentlemen: Subject: Interim Report Pursuant to 10 CFR 21.21 (a)(2) Cooper Nuclear Station, NRC Docket 50-298, DPR-46 Under the notification requirements of 10 CFR 21.21(a)(2), an interim report must be prepared and submitted to the Commission within 60 days of discovery of a deviation or failure to comply that has the potential to have created a substantial safety hazard. Accordingly, the Nebraska Public Power District (the District) is herein notifying the Commission of a condition where safety related calculations provided to the District by General Electric Nuclear Energy were found to contain nonconservative errors. While a preliminary review suggests a substantial safety hazard would not have been created, an in-depth evaluation has yet to be completed. Attachment 1 to this letter provides additional information concerning this condition. Should you have any questions or require any additional information, please contact me. Sincerely, Philip D. Graham Vice President of Nuclear Energy /crm Attachment cc: Regional Administrator USNRC - Region IV Senior Project Manager USNRC - NRR Project Directorate IV-1 NLS970124 September 29, 1997 Page 2 of 2 Senior Resident Inspector USNRC Tyrone Slayton GE Nuclear Energy NPG Distribution Attachment 1 to NLS970124 Page 1 of 2 Interim Report Pursuant to 10 CFR 21.21(a)(2) Cooper Nuclear Station, NRC Docket 50-298, DPR-46 Under the notification requirements of 10 CFR 21.21(a)(2), an interim report must be prepared and submitted to the Commission within 60 days of discovery of a deviation or failure to comply that has the potential to have created a substantial safety hazard. Accordingly, the Nebraska Public Power District (the District) is herein notifying the Commission of a condition where safety related calculations provided to the District were found to contain nonconservative errors. The following provides additional details associated with this condition. Background General Electric Nuclear Energy (GE) was authorized by the District to provide setpoint calculations for analytical limits, allowable values, and nominal trip setpoints for the Cooper Nuclear Station (CNS) Improved Technical Specifications (ITS) project. The work was classified as Essential (Nuclear-Safety Related) and was performed under GE's quality assurance program in accordance with Service Agreement Number 86A-MS2, Task Authorization Number 376. The calculated allowable values were subsequently submitted to the Commission as part of the ITS submittal 1_/. Deviation or Failure to Comply During the preparation of ITS surveillance test procedures using the GE calculated setpoints, it was discovered that several of the setpoint calculations contained errors. Specifically, it was discovered that, in some instances, the calculated setpoints would exceed the calculated allowable values when considering as-left tolerances. Further, a sample review of the setpoint calculations indicated that some setpoint calculations contained errors that affect the allowable values already provided to the Commission in the ITS submittal and the associated nominal setpoints. Substantial Safety Hazard Evaluation Since the setpoint calculations were performed in support of ITS which has yet to be approved and implemented, the errors have no impact to current plant operations. A preliminary review suggests a substantial safety hazard would not have been created; however, an in-depth evaluation has yet to be completed. _________________________ 1_/ Letter (NLS970002) to USNRC from G. R. Horn (NPPD) dated March 27, 1997, "Proposed Change to CNS Technical Specifications Conversion to Improved Standard Technical Specifications, Cooper Nuclear Station, NRC Docket No. 50298, License No. DPR-46" _________________________ Attachment 1 to NLS970124 Page 2 of 2 The Commission has been apprised of the errors with regard to the ITS submittal. To establish the significance of the errors, the setpoint calculations will be reviewed, corrected and approved, and the results compared to those supplied by GE. Discrepancies resulting from errors introduced by GE will then be evaluated to determine if a substantial safety hazard could have been created, assuming the original calculations were implemented as supplied. This in-depth evaluation will be completed by January 9, 1998. ATTACHMENT 3 LIST OF NRC COMMITMENTS Correspondence No: NLS970124 The following table identifies those actions committed to by the District in this document. Any other actions discussed in the submittal represent intended or planned actions by the District. They are described to the NRC for the NRC's information and are not regulatory commitments. Please notify the Licensing Manager at Cooper Nuclear Station of any questions regarding this document or any associated regulatory commitments. COMMITTED DATE COMMITMENT OR OUTAGE To establish the significance of the errors, the setpoint calculations will be reviewed, corrected and approved, and the results compared January 9, 1998 to those supplied by GE. Discrepancies resulting from errors introduced by GE will then be evaluated to determine if a substantial safety hazard could have been created, assuming the original calculations were implemented as supplied. PROCEDURE NUMBER 0.42 REVISION NUMBER 5 PAGE 9 OF 13 *** END OF DOCUMENT ***

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