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Part 21 Report - 1996-661

ACCESSION #: 9607250114 NIAGARA MOHAWK NINE MILE POINT NUCLEAR STATION P.O. BOX 63, LYCOMING, NEW YORK 13093 FAX COVER LETTER NINE MILE POINT UNIT 2 FROM: FAX TELEPHONE NUMBER: (315) 349-1400 NAME: DEPARTMENT: LICENSING/ENVIRONMENTAL TELEPHONE NUMBER: FAX # TO: TOTAL NUMBER OF PAGES FAXED (INCLUDING COVER LETTER): DATE: TIME: MESSAGE: 6.3.3 Obtain the concurrence of the appropriate Vice President or designated alternate that notification is required. If no Vice President (Nuclear) or other responsible Corporate Officer (Nuclear) is available, within two (2) working days, make the NRC notification required by Section 6,3.5 and inform the appropriate Vice President or other responsible Corporate Officer (Nuclear) of the condition when they are available. 6.3.4 Notify the Supervisor of Site Licensing of reportable conditions and jointly determine if the written notification is to be submitted as a 10CFR21 report or as part of a report submittal under other reporting requirements (e.g. 10CFR50.9, 10CFR50.72, 10CFR50.73, 10CFR73.71). If the NRC has been previously notified in writing by another reporting method (e.g. vendor or other utility Part 21, 10CFR50.9, 10CFR50.72, 10CFR50.73, 10CFR73.71), then the reporting requirements of 10CFR21 have already been met. 6.3.5 If required, inform the NRC Operations Center by facsimile at (301)492-8187 (preferred method) or by telephone at (301)951- 0550 of the condition that results in a substantial safety hazard or Significant implication for public health and safety or common defense and security within two (2) calendar days of informing the appropriate Vice President or other responsible Corporate Officer (Nuclear). Verification that the facsimile has been received should be made by calling the NRC Operations Center. 6.3.6 When oral notification to the NRC is made (by facsimile or telephone), ensure that a written report is submitted to the NRC Document Control Desk within thirty (30) calendar days after the appropriate Vice President or other responsible Corporate Officer (Nuclear) is informed that a substantial safety hazard exists. A copy must also be sent to the Regional Administrator, Region I. 6.3.7 If required, prepare a written notification per NIP-IRG-01 containing the following information (required by 10CFR21.21 (b)(3)] as a minimum: a. Name of Niagara Mohawk Officer informing the NRC and the Niagara Mohawk address. b. Identification of the Unit, the activity or the basic component that contains a defect, deviation, or fails to Comply. c. Identification of the firm supplying the component or activity. Page 7 NLAP-IRG-140 Rev 01 ENCLOSURE 1 EVALUATION OF DEVIATION, DEFECT, FAILURE TO COMPLY FORM PART I - REPORTING Nine Mile Point 2 (Affected Unit) DER No. 2-96-1058 Date of Discovery 5/23/96 TYPE OF CONDITION A. Deviation B. Defect 1. Basic Component [x] 1. Deviation [x] a. Structure [ ] 2. Other Condition [ ] b. System C. Failure to Comply c. Component [ ] 1. Atomic Energy Act [ ] d. Design [ ] 2. Rule [ ] e. Inspection 3. Regulation [ ] f. Testing 4. Order g. Consulting 5. License [ ] Service [ ] 2. Other Condition [ ] Description: Standby Gas Treatment System valve 2GTS*MOV3B failed to a potential manufacturing process deficiency which allowed pin affixing the sub to the disk to fall out. PART II - EVALUATION CHECKLIST A deviation related to a Basic Component or a failure to comply shall be evaluated to determine if it presents a substantial safety hazard. A condition is a substantial safety hazard if it causes a major reduction in the degree of protection to the public. Criteria for determining substantial safety hazards include: a) Moderate exposure to or release of licensed material; b) Major degradation of essential safety-related equipment; and c) Major deficiencies involving design, construction, inspection, test or use of license facilities or materials (see NUREG- 302). The following checklist is used to determine if a major reduction in safety exists. If the answer is "yes" to any of the following, it may be reportable per 10CFR part 21 and requires further evaluation. Page 10 NLAP-IRG-140 Rev. 01 ENCLOSURE 1 (Cont) PART II - EVALUATION CHECKLIST (Cont) CONSEQUENCE YES NO 1. Exposures received in excess of 10CFR20 limits for immediate notification. 2. Exposure of an individual in an unrestricted area in excess of 10CFR20 limits. 3. Release of radioactive material to an unrestricted area in excess of 10CFR20 limits. 4. Exceeding a safety limit as defined in the facility technical specifications. 5. A condition which could disable or prevent operation of a system required for safe shutdown, emergency core cooling, post accident containment heat removal or post accident containment atmosphere cleanup. 6. A condition which could disable or reduce the safety margins for the reactor coolant pressure boundary, core or reactor internals, functions or operation. 7. A condition which could disable or prevent operation of the spent fuel storage pool cooling and storage including the fuel racks. 8. A condition which could disable or prevent operation of redundant Class IE electrical systems, including electric and mechanical devices and circuitry. 9. A condition which could disable or prevent operation of the reactivity control systems; that is, control rods, control rod drives, and boron injection systems. 10. A condition which could disable or prevent operation of radioactive waste systems that could create offsite doses greater than Part 100. 11. A condition which could disable or prevent operation of the primary and secondary containment. NLAP-IRG-140 Page 11 Rev. 01 ENCLOSURE 1 (Cont) PART II - EVALUATION CHECKLIST (Cont) CONSEQUENCE YES NO 12. A condition which could disable or prevent VI operation of structures, components, or systems whose continued function is not required, but whose failure could reduce or disable systems that are required. 13. A condition involving the security system which could cause a substantial safety hazard. 14. Other deviations in Basic Components or failures to comply which cause a substantial safety hazard. 15. A condition that creates an unreviewed safety question (10CFR50.59). 16. A condition which does not meet a rule, regulation, license or order and creates a substantial safety hazard. PART III - EVALUATION (to be completed by Nuclear Licensing) (check applicable category) [] Condition does not meet criteria for a potential defect or failure to comply because (attach additional sheets as necessary): [] Condition does not involve a substantial safety hazard because (attach additional sheets as necessary): [] Condition involves a potential substantial safety hazard (attach additional sheets as necessary): [] Condition does not meet criteria for Potential Defect or Failure to Comply, but is reportable under 10CFR50.9. NLAP-IRG-140 Page 12 Rev. 01 ENCLOSURE 1 EVALUATION OF DEVIATION, DEFECT, FAILURE TO COMPLY FORM PLANT: Nine Mile Point Unit 2 DER NO. 2-96-1058 TITLE: Potential Manufacturing Process Deficiency in 2GTS*MOV3B DESCRIPTION OF CONDITION: During pre-planned maintenance activities associated with Standby Gas Treatment System (GTS) Clow valve 2GTS*MOV3B, the valve's stub shaft dowel pin fell out of its hole and into the GTS discharge piping. Although the ensuing investigation did not positively identify a root cause, Engineering conservatively dispositioned the associated Deviation Event Report (DER) indicating that the cause of this event was a manufacturing process deficiency (Niagara Mohawk believes this is an isolated event based on the number of Clow valves inservice and years of service without a similar failure). Specifically, this deficiency was identified as the failure to fully peen over the dowel pin hole in the valve disk. Consequently, the valve stub shaft failed to rotate respective to the main shaft, thus preventing the valve limit switches from property displaying valve position. These valve limit switches are used as input permissives for the GTS train start logic. EVALUATION: The GTS is designed to prevent leakage of radioactive gases and particulates to the environment during accidents by maintaining a negative pressure on the Reactor Building. The GTS consists of two parallel and redundant air filtration assemblies with associated duct work, dampers, controls, and exhaust fans. The discharge of each fan has a normally closed isolation valve (2GTS*MOV3A/3B) which will open upon receiving a GTS start signal. Once 2GTS*MOV3A/3B is fully open, the GTS filter train fans (2GTS*FN1A/1B) are given a permissive signal to start. In the event the GTS was called upon to function, discharge valve 2GTS*MOV3B would have received an open signal. If the dowel pin had already or were to fall out prior to the valve fully opening, the valve would still have opened. However, the valve stub shaft, which positions the valve limit switches, would not have rotated as the valve moved to the open position. Since limit switches indicating the discharge valve in the open position is a permissive to GTS operation, the respective fan would not have started resulting in an inoperable GTS. Assuming a single failure in the redundant GTS train, both trains were potentially inoperable, Therefore, a substantial safety hazard existed. RECOMMENDED CORRECTIVE ACTION (IF REPORTABLE): 1) The redundant GTS train was started and verified operable. Both trains are subject to Technical Specification required surveillance testing to verify operability. 2GTS*MOV3A will be inspected in RFO5. 2) Maintenance personnel reinstalled the dowel pin that fell from 2GTS*MOV3B and re-peened the dowel hole, restoring the valve to operable status. EVALUATION PREPARED BY: Signature Date CONCURRENCE BY: Manager Engineering Date EVALUATION REVIEWED BY: Supervisor Licensing Support Date CONCURRENCE BY: Manager Licensing Date NLAP-IRG-140 Page 13 Rev.01 ENCLOSURE 2 GUIDELINES/CRITERIA FOR DETERMINING REPORTABLE CONDITIONS UNDER 10CFR50.9 FORM DER NO. 2-96-1058 1. Does the condition have significant implication for public health and safety? Yes, No 2. Does the condition have significant implication for common defense and security? Yes, No 3. Information regarding the condition has been/will be provided to the NRC by other reporting or updating requirements. Yes, No If the answer to question 1 or 2 is "YES" and the answer to question 3 is "NO", the condition is reportable under 10CFR50.9 and Procedure Steps 6.3.2, 6.3.3 and 6.3.5 must be completed. COMPLETED BY: Signature DATE: (Title) NLAP-IRG-140 Page 14 Rev- 01 ENCLOSURE 3 REPORTING SUMMARY FORM DER NO. 2-96-1058 A. RESULT OF EVALUATION: REPORTABLE UNDER 10CFR21: YES, NO REPORTABLE UNDER 10CFR50.9: YES, NO B. REPORTED BY OTHER REPORTING REQUIREMENT. NO YES: Letter No. Reported Per Date C. NOTIFY NMPC RESPONSIBLE OFFICER/DIRECTOR: NAME: C. D. Terry TITLE: Vice President - Nuclear Engineering DATE NOTIFIED: 7/22/96 CONCURRENCE WITH EVALUATION: YES NO If NO. Explanation: (No further action required). D. NOTIFY - NRC NRC CONTACT: BY: NAME NAME HOW: Oral Written DATE: (Must be within two calendar days of date in C above). If NRC is notified orally, a written report must be submitted within thirty (30) calendar days of the date in Section C above for reportable conditions under 10CFR21 only. DATE: LETTER NO. E. COMPLETED BY: (Signature) DATE. NLAP-IRG-140 Page 15 Rev. 01 *** END OF DOCUMENT ***

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