05000302/LER-2009-004, Regarding Main Steam Safety Valve Setpoints Outside Required Tolerance Longer than Allowed by Technical Specifications
| ML093280170 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 11/20/2009 |
| From: | Holt J Progress Energy Florida |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 3F1109-03 LER 09-004-00 | |
| Download: ML093280170 (7) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 3022009004R00 - NRC Website | |
text
Progress Energy Crystal River Nuclear Plant Docket No, 50-302 Operating License No. DPR-72 Ref: 10 CFR 50.73 November 20, 2009 3F1 109-03 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001
Subject:
LICENSEE EVENT REPORT 50-302/2009-004-00
Dear Sir:
Please find enclosed Licensee Event Report (LER) 50-302/2009-004-00. The LER discusses three (3) Main Steam Safety Valve lift setpoints being found outside the maximum allowable tolerance for a period longer than allowed by the Crystal River Unit 3 (CR-3) Improved Technical Specifications. This report is being submitted pursuant to 10CFR50.73(a)(2)(i)(B).
The root cause for the out-of-tolerance condition is still under evaluation. CR-3 will provide a supplement to this LER by December 18, 2009.
No new regulatory commitments are made in this letter.
If you have any questions regarding this submittal, please contact Mr. Dan Westcott, Superintendent, Licensing and Regulatory Programs, at (352) 563-4796.
Sin erely, mes W. Holt Plant General Manager Crystal River Nuclear Plant JWH/dwh Enclosure xc:
Regional Administrator, Region II Senior Resident Inspector NRR Project Manager Progress Energy Florida, Inc.
Crystal River Nuclear Plant' 15760 W. Power Line Street Crystal River, FL 34428 j
'-1Q
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2010 (9-2007)
, the NRC may digits/characters for each block) not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE CRYSTAL RIVER UNIT 3 05000302 1 of 6
- 4. TITLE Main Steam Safety Valve Setpoints Outside Required Tolerance Longer Than Allowed By Technical Specifications
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED FACILITYENAME7DOCKETRNUMBER MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR FACILITYNAME DOCK05000 FACILITY NAME DOCKET NUMBER 09 22 2009 2009 - 004 -
00 11 20 2009 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply)
El 2012201(b)
[l 20.2203(a)(3)(i)
El 50.73(a)(2)(i)(C)
El 50.73(a)(2)(vii) 1 [1 20.2201(d)
El 20.2203(a)(3)(ii)
El 50.73(a)(2)(ii)(A)
E3 50.73(a)(2)(viii)(A)
[I 20.2203(a)(1)
[I 20.2203(a)(4)
El 50.73(a)(2)(ii)(B)
[I 50.73(a)(2)(viii)(B)
El 20.2203(a)(2)(i)
[I 50.36(c)(1)(i)(A)
El 50.73(a)(2)(iii)
El 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL 0l 20.2203(a)(2)(ii)
El 50.36(c)(1)(ii)(A)
[I 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x)
[I 20.2203(a)(2)(iii)
El 50.36(c)(2)
El 50.73(a)(2)(v)(A)
El 73.71(a)(4)
El 20.2203(a)(2)(iv)
El 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
El 73.71(a)(5) 100%
[1 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A)
El 50.73(a)(2)(v)(C)
[E OTHER El 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in NRC Form 366A
- 12. LICENSEE CONTACT FOR THIS LER FACILITY NAME TELEPHONE NUMBER (Include Area Code)
Dennis W. Herrin, Lead Engineer (Licensing and Regulatory Programs) 352-563-4633CAUSE SYSTEM COMPONENT MANU-REPORTABLE I
SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX
CAUSE
FACTURER TO EPIX X
SB RV D243 Y
1
- 14. SUPPLEMENTAL REPORT EXPECTED
- 15. EXPECTED MONTH DAY YEAR SUBMISSION [D YES (If yes, complete 15. EXPECTED SUBMISSION DATE)
El NO DATE 12 18 2009 ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines)
On September 22, 2009, Progress Energy Florida, Inc., (PEF) Crystal River Unit 3 (dR-3) was in MODE 1 (POWER OPERATION) at approximately 100 percent RATED THERMAL POWER.
While performing surveillance procedure SP-650, "ASME Code Safety Valves Test," on the 'A' Once Through Steam Generator, the lift setpoint for Main Steam Safety Valve (MSSV) MSV-34 was found above its maximum allowable tolerance. Subsequently, three of ten tested MSSVs were found to have lift setpoints above/below their maximum allowable tolerance. Improved Technical Specification (ITS) 3.7.1 states that the MSSVs shall be operable as specified in Table 3.7.1-1 in MODES 1, 2 and 3. To be operable, the MSSV lift setpoints must be within the maximum allowable tolerance of +/- 3%. The existence of similar discrepancies in multiple relief valves is an indication that the discrepancies may have developed over a period of time.
Therefore, PEE concludes that multiple MSSVs were inoperable during plant operation for a period longer than allowed by ITS and the condition is reportable under 10CFR50.73(a)(2)(i)(B).
This condition does not represent a reduction in the public health and safety. The cause for this condition is still under evaluation. The three MSSVs were adjusted and retested satisfactorily.
Similar occurrences were reported to the NRC in Licensee Event Reports 50-302/2001-002-00 and 50-302/2003-002-00.
NRC FORM 366 (9-2007)
PRINTED ON RECYCLED PAPERU.S. NUCLEAR REGULATORY COMMISSION (9-2007)*
LICENSEE EVENT REPORT (LER)
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE II YEAR SEQUENTIAL IREVISION I
NUMBER I NUMBER CRYSTAL RIVER UNIT 3 1 05000-302 2009 004 00 2
OF 6
EVENT DESCRIPTION
On September 22, 2009, Progress Energy Florida, Inc., (PEF) Crystal River Unit 3 (CR-3) was in MODE 1 (POWER OPERATION) at approximately 100 percent RATED THERMAL POWER.
While performing surveillance procedure SP-650, "ASME Code Safety Valves Test," on the 'A' Once-Through Steam Generator (OTSG) [SB, SG], the Main Steam Safety Valve (MSSV) MSV-34 [SB, RV] lift setpoint was found above its maximum allowable tolerance. The maximum allowable tolerance specified in Improved Technical Specification (ITS) Table 3.7.1-1 is +/- 3% of the lift setpoint. MSV-34 lifted at +4.3 percent of its lift setpoint. The Required Actions associated with ITS 3.7.1, Condition A, became applicable.
There are two OTSGs at CR-3. Each OTSG has two main steam lines. Each main steam line has four MSSVs with staggered relief pressures of 1050 pounds per square inch gauge (psig),
1070 psig, 1090 psig and 1100 psig. The MSSVs are required to be tested for relief setpoint accuracy in accordance with the CR-3 Inservice Testing Pump and Valve Program. This program requires that each MSSV be tested once every five years. Six MSSVs were scheduled to be tested prior to the start of Refueling Outage 16 (R16) on September 26, 2009.
Including MSV-34, three of the six MSSVs scheduled to be tested were found with lift setpoints outside of their maximum allowable tolerance. SP-650 states that for any valve tested to satisfy American Society of Mechanical Engineers (ASME) Operations and Maintenance (OM) Code requirements, whose setpoint is outside the "as-found" maximum allowable tolerance (+/- 3% of the lift setpoint), two additional valves from its group shall be tested. Since two of the three valves found with lift setpoints outside of their maximum allowable tolerance were from the same group, only two additional valves were left in that group to be tested. The third valve found with its lift setpoint outside of its maximum allowable tolerance resulted in two additional valves from its group being tested. A total of four additional valves were tested. None of these valves were found with lift setpoints outside of their maximum allowable tolerance.
Tag Main Steam Design As-Found As-Found %
Line Pressure Pressure MSV-34 (Orig.)
Al 1050 1094.7
+4.3 MSV-36 (Orig.)
B2 1050 1001.4
- - 4.6 MSV-38 (Orig.)
Al 1070 Acceptable N/A MSV-40 (Orig.)
Al 1090 Acceptable N/A MSV-43 (Orig.)
Al 1090 1033.6
- - 5.2 MSV-46 (Orig.)
A2 1100 Acceptable N/A MSV-33 (Add)
A2 1050 Acceptable N/A MSV-35 (Add)
B1 1050 Acceptable N/A MSV-42 (Add)
A2 1090 Acceptable N/A MSV-44 (Add)
B1 1090 Acceptable N/A ITS 3.7.1 states that the MSSVs shall be operable as specified in Table 3.7.1-1 in MODES 1, 2 and 3. With one or more required MSSVs inoperable, THERMAL POWER shall be reduced to less than the reduced power limit of Table 3.7.1-1 within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> (Required Action A.1) and the nuclear overpower trip setpoint shall be reduced in accordance with Table 3.7.1-1 within 12PRINTED ON RECYCLED PAPERU.S. NUCLEAR REGULATORY COMMISSION (9-2007)
LICENSEE EVENT REPORT (LER)
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE SEQUENTIAL I REVISION YEAR NUMBER NUMBER CRYSTAL RIVER UNIT 3 05000-302 2009 004 00 3
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hours (Required Action A.2). Each MSSV found with its lift setpoint outside of the maximum allowable tolerance range was restored to an operable status within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. Therefore, ITS 3.7.1, Required Actions A.1 and A.2, were not performed.
In accordance with NUREG-1 022, "Event Reporting Guidelines 10 CFR 50.72 and 50.73,"
Revision 2, Section 3.2.2, the existence of similar discrepancies in multiple relief valves is an indication that the discrepancies may well have developed over a period of time. Based on this guidance, PEF concludes that multiple MSSVs were inoperable during plant operation for a period longer than allowed by ITS. This condition is reportable under 10CFR50.73(a)(2)(i)(B).
SAFETY CONSEQUENCES
The MSSVs provide overpressure protection for the Main Steam System piping and the OTSGs.
The design pressure for the Main Steam System is 1050 psig. Enhanced Design Basis Document Tab 6/10, "Main Steam System," states the total MSSV capacity to be such that steam pressure will not exceed 110% of system designpressure (1155 psig) for the limiting overpressurization event. The limiting event that challenges the MSSV capacity is the Turbine Generator trip that occurs at 112% rated thermal power. Only one of the tested MSSVs (MSV-
- 34) was found with its lift setpoint slightly above its maximum allowable tolerance by +1.3%. As such, the MSSVs were considered to be fully capable of providing OTSG overpressure protection.
The primary concern associated with MSSV lift setpoints being found below their maximum allowable tolerance is the risk of over cooling the Reactor Coolant System (RCS) [RC]. Two of the tested MSSVs (MSV-36 and MSV-43) were found with their lift setpoint slightly below the maximum allowable tolerance (-1.6% and -2.2%, respectively). The SP-650 testing verified that the MSSVs were capable of closing at pressures that would not challenge the plant's ability to maintain acceptable post-accident RCS pressures and temperatures.
Based on the above discussion, PEF concludes that the inoperable condition of MSV-34, MSV-36 and MSV-43 did not represent a reduction in the public health and safety. This event does not meet the definition of a Safety System Functional Failure as defined in Nuclear Energy Institute (NEI) 99-02, "Regulatory Assessment Performance Indicator Guideline."
CAUSE
CR-3 requires additional time to complete the root cause evaluation for multiple MSSV lift setpoints being found outside of the maximum allowable tolerance. MSV-34, MSV-36 and MSV-43 were removed from the plant after shutdown for R16, sent to Wyle Laboratories for repairs/refurbishment by Dresser, returned and re-installed in the plant. Valve test results were received from Wyle Laboratories on November 12, 2009, and need to be factored into the root cause evaluation. A supplemental Licensee Event Report (LER) will be submitted to the NRC by December 18, 2009.PRINTED ON RECYCLED PAPERPRINTED ON RECYCLED PAPERU.S. NUCLEAR REGULATORY COMMISSION (9-2007)
LICENSEE EVENT REPORT (LER)
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE SEQUENTIAL I REVISION YEAR NUMBER NUMBER CRYSTAL RIVER UNIT 3 105000-302 2009 004 00 4
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CORRECTIVE ACTIONS
- 1. MSV-34, MSV-36 and MSV-43 (Dresser, Model 3707RA) were restored to an operable status within 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> of identifying the associated lift setpoints being outside the maximum allowable tolerance.
- 2.
MSV-34, MSV-36 and MSV-43 were subsequently removed from service, refurbished by the vendor and re-installed in the plant (Work Orders 1625933, 1625792 and 1500994 respectively).
- 3. Additional corrective actions are being considered and will be tracked in the CR-3 Corrective Action Program under Nuclear Condition Report 356521.
PREVIOUS SIMILAR EVENTS
Previous occurrences of MSSV setpoints being found outside their required tolerance have been reported to the NRC in Licensee Event Reports 50-302/2001-002-00 and LER 50-302/2003-002-00.
ATTACHMENTS - Abbreviations, Definitions, and Acronyms - List of CommitmentsPRINTED ON RECYCLED PAPERPRINTED ON RECYCLED PAPERU.S. NUCLEAR REGULATORY COMMISSION (9-2007)
LICENSEE EVENT REPORT (LER)
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE Y SEQUENTIAL I REVISION YEAR NUMBER INUMBER CRYSTAL RIVER UNIT 3 105000-302 2009 004 00 5
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ATTACHMENT 1 ABBREVIATIONS, DEFINITIONS AND ACRONYMS ASME CFR CR-3 ITS MSV MSSV NEI NUREG O&M Code OTSG PEF psig R16 RCS SP NOTES:
American Society of Mechanical Engineers Code of Federal Regulations Crystal River Unit 3 Improved Technical Specifications Main Steam Valve Main Steam Safety Valve Nuclear Energy Institute NRC Nuclear Regulation Operations & Maintenance Code Once Through Steam Generator Progress Energy Florida, Inc.
pounds per square inch gauge Refueling Outage 16 Reactor Coolant System Surveillance Procedure Improved Technical Specification Defined terms appear capitalized in LER text
{e.g., MODE 1}.
Defined terms/acronyms/abbreviations appear in parenthesis when first used
{e.g., Reactor Building (RB)}.
EIIS codes appear in square brackets {e.g., reactor building penetration [NH, PEN])PRINTED ON RECYCLED PAPERPRINTED ON RECYCLED PAPERU.S. NUCLEAR REGULATORY COMMISSION (9-2007)
LICENSEE EVENT REPORT (LER)
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE YEA I SEQUENTIAL REVISION I YEAR NUMBER NUMBER CRYSTAL RIVER UNIT 3 05000-302 2009 004 00 I
6 OF 6
LIST OF COMMITMENTS The following table identifies those actions committed by PEF in this document. Any other actions discussed in the submittal represent intended or planned actions by PEF. They are described to the NRC for the NRC's information and are not regulatory commitments. Please notify the Superintendent, Licensing and Regulatory Programs of any questions regarding this document or any associated regulatory commitments.
COMMITMENT
DUE DATE No new regulatory commitments are contained in this N/A submittal.PRINTED ON RECYCLED PAPERPRINTED ON RECYCLED PAPER