ML18068A028
| ML18068A028 | |
| Person / Time | |
|---|---|
| Site: |  |
| Issue date: | 03/07/2018 |
| From: | Sharp S Northern States Power Company, Minnesota, Xcel Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-PI-18-006 LER-2018-001-00 | |
| Download: ML18068A028 (6) | |
Text
Xcel Energy@ MAR 0 7 2018 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Prairie Island Nuclear Generating Plant, Units 1 and 2 Docket Nos. 50-282 and 50-306 Renewed Facility Operating License Nos. DPR-42 and DPR-60 Prairie Island Nuclear Generating Plant 1717 Wakonade Drive East Welch, MN 55089 L-PI-18-006 10 CFR 50.73 Licensee Event Report 50-282/2018-001-00, 121 Motor Driven Cooling Water Pump Auto Start due to Smoking Packing on 11 Cooling Water Pump Northern States Power Company, a Minnesota corporation, doing business as Xcel Energy (hereafter "NSPM"), encloses Licensee Event Report (LER) 50-282/2018-001-00, 121 Motor Driven Cooling Water Pump Auto 'start due to Smoking Packing on 11 Cooling Water Pump. If there is any question or if any additional information is needed, please contact Jeff Kivi, at 651-267-7309.
SummarY of Commitments This letter contains no new commitments and no changes to existing commitments Site Vice President, Prairie Island Nuclear Generating Plant Northern States Power Company-Minnesota Enclosure cc: Regional Administrator, Region Ill, USNRC Project Manager, Prairie Island Nuclear Generating Plant, USNRC Resident Inspector, Prairie Island Nuclear Generating Plant, USNRC Department of Commerce, State of Minnesota ENCLOSURE 1 LICENSEE EVENT REPORT 50-282/2018-001-00 4 Pages Follow NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2017)
Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.
LICENSEE EVENT REPORT (LER) Reported lessons learned are incorporated into the licensing process and fed back to industry.
' Send comments regarding burden estimate to the Information Services Branch (T -2 F43), U.S. (See Page 2 for required number of digits/characters for each Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to lnfocollects.
- " block) Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, (See NUREG-1022, R.3 for instruction and guidance for completing this NEOB-1 0202, (3150-01 04), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, form htt[1://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1 022/r3/) the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY.NAME DOCKET NUMBER 13. PAGE Prairie Island Nuclear Generating Plant Unit 1 05000 282 1 OF 4 4. TITLE 121 Motor Driven Cooling Water Pump Auto Start due to Smoking Packing on 11 Cooling Water Pump 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED SEQUENTIAl FACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR REV MONTH DAY YEAR Prairie Island Unit 2 NUMBER NO. 05000306 1 8 2018 2018
-001 -00 3 7 2018 FACILITY NAME DOCKET NUMBER 05000 9. OPERATING MODE 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) Unit 1 Mode 1 D 20.2201(b)
D 20.2203(a)(3)(i) 0 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A)
Unit 2 Mode 1 D 20.2201(d)
D 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(B)
D 50. 73{a)(2)(viii)(B) 0 20.2203(a)(1)
D 20.2203(a)(4)
D 50.73(a)(2)(iii) 0 50.73(a)(2)(ix)(A) 0 20.2203(a)(2)(i) 0 50.36(c)(1)(i)(A) 18] 50.73(a)(2)(iv)(A)
D 50.73{a)(2)(x)
- 10. POWER LEVEL 0 20.2203(a)(2)(ii) 0 50.36(c)(1)(ii)(A)
D 50.73(a)(2)(v)(A)
D 73.71 (a)(4) 0 20.2203(a)(2)(iii)
D 50.36(c)(2)
D 50.73(a)(2)(v)(B)
D 73.71 (a)(5) Unit 1 100% 0 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii)
D 50.73(a)(2)(v)(C)
D 73.77(a)(1)
Unit 2 100% D 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(D)
D 73.77(a)(2)(i)
D 20.2203{a)(2)(vi)
D 50.73(a)(2)(i)(B)
D 50.73(a)(2)(vii)
D 73.77(a)(2)(ii) 0 50.73(a)(2)(i)(C) 0 OTHER Specify in Abstract below or in NRC Form 366A 12. LICENSEE CONTACT FOR THIS LER LICENSEE CONTACT NUMBER (Include Area Code) !Jeff Kivi, Site Regulatory Affairs Manager 12-342-7309
- 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CAUSE SYSTEM COMPONENT MANU-REPORTABLE CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX FACTURER TO EPIX D Bl p W318 No 14. SUPPLEMENTAL REPORT EXPECTED 15. EXPECTED MONTH DAY YEAR D YES (If yes, complete 15. EXPECTED SUBMISSION DATE) [g) NO SUBMISSION DATE ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) On January 8, 2018, Prairie Island Nuclear Generating Plant (PINGP) staff were running the 11 Cooling Water (CL) pump for post-maintenance testing. At 1437 CST, operators stopped 11 CL pump following a report from Maintenance staff that the inboard pump packing was smoking. Shortly after operators secured 11 CL pump the 121 Motor Driven Cooling Water Pump (MDCLP) auto-started and supplied the CL header. This event is reportable under 10 CFR 50. 73(a)(2)(iv)(A) as an event that resulted in automatic actuation of an emergency service water system. The cause of the 121 MDCLP auto-start was determined to be low CL header pressure after 11 CL pump was secured. Operators secured the 11 CL pump when they received the report that the inboard pump packing was smoking. Investigation found the most likely cause of the smoking pump packing was due to inadequate procedural guidance regarding packing replacement criteria.
NRC FORM 366 (04-2017)
NRC FORM 366A {04-2017)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1 022/r3/) APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons learned are incorporated into the licensing process and fed back to Industry.
Send comments regarding burden estimate to the Information Services Branch (T-2 F43}, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-1 0202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY NAME 2. DOCKET NUMBER 3. LER NUMBER YEAR Prairie Island Nuclear Generating Plant 05000-282 Unit 1 2018 NARRATIVE DESCRIPTION OF EVENT SEQUENTIAL NUMBER -001 REV NO. -00 On January 8, 2018, Prairie Island Nuclear Generating Plant (PINGP) Unit 1 and Unit 2 were both operating at 100% in MODE 1 and PINGP staff were running the 11 Cooling Water (CL) pump 1 for post-maintenance testing. The 11 CL pump is a nonsafety-related pump manufactured by Worthington Pump Corporation model number 16-LN-28.
At 1437 CST, operators stopped 11 CL pump following a report from Maintenance staff that the inboard pump packing was smoking. Shortly after operators secured 11 CL pump the 121 Motor Driven Cooling Water Pump (MDCLP) auto-started and supplied the CL The 121 MDCLP is designed to start automatically if CL header pressure drops to 80 pounds per square inch gauge (psig). EVENT ANALYSIS The PINGP CL System is a shared system for Units 1 and 2 and provides a heat sink for the removal of process and operational heat from safety-related components during a design basis accident or transient.
During normal operation and shutdown, the CL System also provides this function for various safety-related and nonsafety-related components.
PINGP Units 1 and 2 share five CL pumps: one motor-driven and two diesel-driven vertical pumps that take a suction from the safeguards bay and two nonsafety-related motor-driven cooling water pumps. All five pumps are connected to a common pump discharge that directs CL flow into a header that splits into two trains upon
- receipt of a Safety Injection signal. The 121 MDCLP can function as a safeguards replacement when either safeguards diesel-driven cooling water pump is taken out of service. In this configuration, the pump is aligned manually to the appropriate train of safeguards power and motor:-operated valves are administratively disabled in accordance with Technical Specifications.
This event is reportable under 10 CFR 50.73(a)(2)(iv)(A) as an event that resulted in automatic actuation of an emergency service water system. SAFETY SIGNIFICANCE There was no radiological, environmental, or industrial impact associated with the 121 MDCLP auto-start, and the health and safety of the public were not affected.
The auto-start of the 121 Motor Driven Cooling Water Pump did not challenge nuclear safety as all plant systems responded as designed; therefore, this event does not represent a safety system functional failure for Unit 1 or Unit 2. 1 EllS Component Identifier:
P 2 EllS System Code: 81 NRC FORM 3668 (04-2017)
Page 2 of 4 NRC FORM 366A (04-2017)
U.S. NUCLEAR REGULATORY COMMISSION APPROVED BYOMB: NO. 3150-0104 EXPIRES: 3/31/2020 LICENSEE EVENT REPORT (LER) CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form h!lp://www.
nrc.gov/read ing-rm/doc-colleclions/nuregsfstaff/sr1 0221r3f) Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons learned are incorporated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY NAME 2. DOCKET NUMBER 3. LER NUMBER YEAR Prairie Island Nuclear Generating Plant 05000-282 Unit 1 2018 CAUSE SEQUENTIAL NUMBER -001 REV NO. -00 The cause of the 121 MDCLP auto-start was determined to be low CL header pressure after 11 CL pump was secured. Operators secured the 11 CL pump when they received the report that the inboard pump packing was smoking. Investigation found the most likely cause of the smoking pump packing was due to inadequate procedural guidance.
The maintenance procedure did not provide specific criteria for packing inspection nor did it provide guidance requiring replacement of the packing if packing adjustments were no longer effective at managing external seal leak-off.
CORRECTIVE ACTION(s)
- 1. The 11 Cooling Water pump was repaired and returned to service. 2. The 21 Cooling Water pump packing will be inspected.
- 3. The work instructions for monthly and two-year packing preventive maintenance on 11 and 21 Cooling Water pumps will be updated to include inspection criteria providing guidance requiring replacement of the packing if packing adjustments are no longer effective at managing external seal leak-off.
PREVIOUS SIMILAR EVENTS Since 2009 there have been six, licensee event reports in regards to the 121 Cooling Water pump auto-starting for PINGP. All of these were cases where 121 Cooling Water pump behaved as expected in response to cooling water header pressure transients, but none of the previous transients were due to a similar shutdown of a CL pump in response to smoking packing. LER 50-282/2009-002, Unplanned Safety Related Actuation of 121 Cooling Water Pump (Agencywide Documents Access and Management System (ADAMS) Accession Number ML091390396).
On 3/19/2009, 121 MDCLP auto-started when 12 DDCLP was tripped iii accordance with procedure resulting in a transient of the cooling water system pressure.
The momentary drop in pressure was large enough to auto-start the 121 MDCLP while it was aligned for safeguards service. LER 50-282/2011-001, Unplanned Actuation of 121 Motor Driven Cooling Water Pump (ADAMS Access Number ML 112840145).
On 12/23/2010, the 121 MDCLP was not aligned as a safeguards replacement pump and auto-started.
The actuation of the 121 MDCLP was determined to be reportable under 10 CFR 50. 73(a)(2)(iv)(A).
Corrective actions to resolve the issue included performing a Cooling Water System review to determine methods and any single point vulnerabilities that can be performed to minimize the potential for starts of a cooling water pump. Operating procedures were evaluated to determine if procedural or operation period changes can be made to reduce the likelihood of a Cooling Water Pump. LER 50-282/2012-002, Unplanned Actuation of 121 Motor Driven Cooling Water Pump (ADAMS Accession Number ML 12152A 189). On 4/2/2012, while PINGP Unit 1 was operating at 100% power, 121 MDCLP auto-started while shutting down 22 DDCLP. The corrective action was to revise operating procedure C35 to ensure two MDCLPs are running prior to stopping the DDCLP. NRC FORM 366A (06-2016)
Page 3 of 4 NRC FORM 366A (04-2017)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT {LER) CONTINUATION SHEET (See NUREG-1022, R.3 for instruction and guidance for completing this form http://www.nrc.gov/reading-rm/doc-
- collections/nuregs/staff/sr1 022/r3l) APPROVED BY OMB: NO. 3150-0104 EXPIRES: 3/31/2020 Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. Reported lessons learned are incorporated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the Information Services Branch (T-2 F43), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by e-mail to lnfocollects.Resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-1 0202, (3150-01 04), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person Is not required to respond to, the information collection.
- 1. FACILITY NAME 2. DOCKET NUMBER 3. LER NUMBER YEAR Prairie Island Nuclear Generating Plant 05000-282 Unit 1 2018 SEQUENTIAL NUMBER -001 REV NO. -00 LER 50-282/2016-002, Listed System Actuation
-Motor-Driven Cooling Water Pump Auto-Start (ADAMS Number ML 16085A181).
On 1/29/2016, PINGP performed a planned overspeed post-maintenance test (PMT) of 22 Diesel Driven Cooling Water Pump in accordance with plant maintenance procedure.
During the overspeed trip test PMT, 22 DDCLP tripped as expected and 121 MDCLP unexpectedly started automatically on low pressure in the cooling water pump discharge header. LER 50-282/2016-005, 121 Motor Driven Cooling Water Pump Auto Started (ADAMS Accession Number ML 16281A208).
On 8/21/2016, PINGP 2RY Transformer locked out. The 121 MDCLP stopped due to loss of power and then automatically restarted when sequenced by the load sequencer.
The pump auto started on low pressure in the cooling water pump discharge header. LER 50-282/2016-006, 121 Motor Driven Cooling Water Pump Auto Start (ADAMS Accession Number ML 17046A656).
On December 18, 2016, at 0818 COT, a fire in the PINGP Switch Yard due to 8H8 Breaker current transformer catastrophic failure resulted in an auto start of the 121 MDCLP on low header pressure (80 psig). NRC FORM 366A (06-2016)
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