05000266/LER-2005-002, And LER 05-002-00 for Point Beach, Units 1 and 2 Re Unanalyzed Conditions Due to Inadvertent Omission of Safe Shutdown Equipment from Fire Organizational Plan
| ML052280351 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 08/08/2005 |
| From: | Koehl D Nuclear Management Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NRC 2005-0097 LER 05-001-00, LER 05-002-00 | |
| Download: ML052280351 (8) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii)(A), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(iii) 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)(viii)(B) |
| 2662005002R00 - NRC Website | |
text
Committed to Nuclear Excellene Point Beach Nuclear Plant Operated by Nuclear Management Company, LLC August 8, 2005 NRC 2005-0097 10 CFR 50.73 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington DC 20555 Point Beach Nuclear Plant Units 1 and 2 Docket Nos. 50-266 and 50-301 License Nos. DPR-24 and DPR-27 Licensee Event Reports 266/301/2005-001-00 and 266/301/2005-002-00 Unanalyzed Conditions due to Inadvertant Omission of Safe Shutdown Equipment from Fire Organizational Plan and Deficiency in Appendix R Safe Shutdown Strategy for Charging Pump Capability Enclosed are Licensee Event Reports (LER) 266/301/2005-001-00 and 266/301/2005-002-00 for the Point Beach Nuclear Plant Units 1 and 2. LER 266/301/2005-001-00 describes the discovery that the Point Beach Fire Organizational Plan omitted some safe shutdown equipment, resulting in the plan not being aligned with the safe shutdown analysis. LER 266/301/2005-002-00 describes the discovery that control cables associated with charging pump 1 P-2C were located within a fire area such that the pump would not be able to be started from the control room given fire damage to these cables. These conditions are reportable in accordance with 10 CFR 50.73(a)(2)(ii)(B).
This submittal contains no new or revised regulatory commitments.
Ov Dennis L. Koehl Site Vice-President, Point Beach Nuclear Plant Nuclear Management Company, LLC Enclosures (2) cc:
Administrator, Region Ill, USNRC Project Manager, Point Beach Nuclear Plant, USNRC Resident Inspector, Point Beach Nuclear Plant, USNRC PSCW 6590 Nuclear Road
- Two Rivers, Wisconsin 54241 Telephone: 920.755.2321
'
Ll
NRC FORM 366 U.S. NUCLEAR REGULATORY APPROVED BY OMB NO. 3150-0104 EXPIRES 7-31-2004 (7-2001)
COMMISSION Estimated burden perresponsetocomplywiththis mandatoryinformaion collection request:
50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />. Reported lessons learned are incorporated Into the licensing process and fed back to industry. Send comments regarding burden estimate to the Records Management Branch LICENSEE EVENT REPORT (LER)
(T.6 ES). U.S. NucearRegulatory Commission.Washington, DC 20555-0001. or by Internet a-mai tobds~
rc~ov.an totheDek OficrOffice of Information and Regu 03or Iffais (See reverse for required number of measue 20 (5 1)s e of Manapement and Budget, Washington, DC 20503 If a digits/characters; for each block) men sdt moeIfraincleto osntdisplay a currently valid OMB control number, the NRC may not conduct or sponsor, and a person Is not required to respond to, the FAC.ILTY NAUF £11 DOCrKET NIIMRER 121 PARE t31 POINT BEACH NUCLEAR PLANT UNIT I I
05000266 OF 3
TITLE (4)
UNANALYZED CONDITION DUE TO INADVERTANT OMISSION OF SAFE SHUTDOWN EQUIPMENT FROM FIRE ORGANIZATIONAL PLAN EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
I FACILITY NAME DOCKET NUMBER I
~~SEQUENTIAL REVIIf MO DAY YEAR YEAR NUMBER NO MO DAY YEAR PT BEACH UNIT 2 05000301 FACILITY NAME DOCKET NUMBER 06 08 2005
- 2005, 001 -0008 05 2005.
OPERATING THIS REPORT IS SUBMITTED PURSUANTTO THE REQUIREMENTS OF 10 CFR0: (Check all thatapply) (11)
MODE (9) 1/6 _
20.2201(b) 120.2203(a)(3)(ii)
X 50.73(a)(2)(i)(B) 50.73(a)(2)(ix)(A)
POWER
_ 20.2201 (d)
_ 20.2203(a)(4) 50.73(a)(2)(iil) 50.73(a) 2)(x)
LEVEL (10) 100/0 _
20.2203(a)(1)
_ 50.36(c)(1)(i)(A) 50.73(a)(2)(iv)(A) 73.71 (a)(4) 20.2203(a)(2)i) _
50.36(c)(1)(ii)(A) 5_ 0.73(a)(2)(v)(A) 73.71 (a)(5) 20.2203(a)(2)(ii)
_ 50.36(c)(2) 50.73(a)(2)(v)(B)
Speci in Abstract below or In 20.2203(a)(2)(iii)
_ 50.46(a)(3)(ii) 50.73(a)(2)(v)(C) 20. 2203a(2)(iv 50.73(a)(2)(i)(A)
_ 50.73(a)(2)(v)(D) 20.2203(a)(2)(v)
_ 50.73(a)(2)(i)(B)
_ 50.73(a)(2)(vii)
- 20.2203(a)(2)(vi)
_ 50.73(a)(2)(i)(C)
_ 50.73(a)(2)(vii)(A) i 20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(vIii)(B) t LICENSEE CONTACT FOR THIS LER (12)
NAME TELEPHONE NUMBER (Include Area Code)
F. Hennessy 1
920-755-6461 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
MANU-REPORTABLE MANU-REPORTABLE
CAUSE
SYSTEM COMPONENT FACTURER TO EPIX I
CAUSE
SYSTEM COMPONENT FA CTURER TO EPIX SUPPLEMENTAL REPORT EXPECTED (14)
PSUBMIS N
MONTH DAY YEAR IYES (If yes, complete EXPECTED SUBMISSION DATE).
X NO DATE (15) l I
ABSTRACT (Lmit to 1400 spaces, L.e., approximately 15 single-spaced typewritten lines) (16)
On June 8, 2005, NMC staff determined that Revision 8 of Point Beach Fire Organizational Plan (FOP) 1.2, omitted some safe shutdown equipment. Because of these omissions, FOP 1.2, Revision 8, was not aligned with the Safe Shutdown Analysis. As a result, some of the manual actions that would be necessary to accomplish safe shutdown were no longer identified. FOP 1.2 guides operators on plant operation for fires within safe shutdown areas. This guidance includes a list of safe shutdown equipment affected by a postulated fire and the manual actions that may be required to compensate for the fire damage. Investigation determined the omissions were introduced in FOP 1.2, Revision 6 (effective November 1, 2004). The missing procedural guidance may have resulted in the omission of safety significant operator actions (which are credited in the Safe Shutdown Analysis) had a fire occurred while FOP 1.2, Revision 6 was in effect.
FOP 1.2, Revisions 7 and 8, also carried on the omission of some safety equipment. A temporary change corrected this condition on June 8, 2005. FOP 1.2 Revision 9, was issued to correct this condition on June 29, 2005.
On July 18, 2005, NMC identified a similar issue with Revision 9 of FOP 1.2.
FOP 1.2 Revision 10, was issued to correct this condition on July 22, 2005.U.S. NUCLEAR REGULATORY COMMISSION (7-2001)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1)
DOCKETNUMBER 2 LER NUMBER 6 PAGE (3)
YEAR SEQUENTNAL REVISION Point Beach Nuclear Plant Unit 1 05000266 NUMBER NUMBER 2 of 3 2005 001 00 TEXT (if nore space Is required, use additional copies of NRC Form 366A) (17)
Event Description
On June 8, 2005, NMC staff determined that Revision 8 of Point Beach Fire Organizational Plan (FOP) 1.2 omitted some safe shutdown equipment. Because of these omissions, FOP 1.2, Revision 8, was not aligned with the Safe Shutdown Analysis. As a result, some of the manual actions that would be necessary to accomplish safe shutdown were no longer identified. FOP 1.2 guides operators on plant operation for fires within safe shutdown areas. This guidance includes a list of safe shutdown equipment affected by a postulated fire and the manual actions that may be required to compensate for the fire damage. Investigation determined the omissions were introduced in FOP 1.2, Revision 6 (effective November 1, 2004). The missing procedural guidance may have resulted in the omission of safety significant operator actions (which are credited in the Safe Shutdown Analysis) had a fire occurred while FOP 1.2, Revisions 6 through 8, were in effect.
This condition was reported to the NRC on June 8, 2005, via the emergency notification system.
A temporary change corrected this condition on June 8, 2005. FOP 1.2 Revision 9, was issued to correct this condition on June 29, 2005.
On July 18, 2005, NMC Staff identified a similar issue with Revision 9 of FOP 1.2. A required manual action was omitted in one safe shutdown area, and an incorrect manual action was identified in another area. Similar to the examples discussed above, this condition also existed in Revisions 6, 7, and 8 of FOP 1.2. The procedural guidance may have resulted in the omission of safety significant operator actions had a fire occurred while FOP 1.2, Revisions 6 through 9 were in effect.
FOP 1.2 Revision 10, was revised to correct this condition on July 22, 2005.
Event Analysis
The specific procedural guidance that was omitted from FOP 1.2, Revisions 6 through 8, were the following manual actions:
Unit 1 Turbine Driven Auxiliary Feed Water (AFW) Pump1 (1 P-29) Minimum Recirculation Valve2 (lAF-4002) can lose power due to a fire within fire areas AOl-A, A01-CN, A18, and A19. This pump and this valve are credited for safe shutdown for this area. Manual action would be necessary to gag valve open.
Unit 2 Turbine Driven AFW Pump (2P-29) Minimum Recirculation Valve (2AF-4002) can lose power due to a fire within fire areas AlO, A16, and A17. This pump and this valve are credited for safe shutdown for this area. Manual action would be necessary to gag valve open.
Unit 1 Turbine Driven AFW Pump (I P-29) Service Water Supply Valve (IAF-4006) can lose power due to a fire within fire area A06. This pump and valve are credited for safe shutdown for this area.
Manual action would be necessary to take manual local control of this valve to provide continued suction for the AFW pump after drain down of the Condensate Storage Tank (CST).
' (EIIS Component Identifier Code: P) 2 (EIIS Component Identifier Code: V)U.S. NUCLEAR REGULATORY COMMISSION (7-2001)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6 PAGE 3 YEAR SEQUENTIAL REVISION Point Beach Nuclear Plant Unit 1 05000266 NUMBER NUMBER 3 of 3 l2005 01 00 l
TEXT (if more space is required, use additional copies of NRC Form 366A) (17)
The specific procedural guidance that was omitted from one fire area, and incorrectly identified in a second fire area, from FOP 1.2, Revisions 6 through 9, was the following:
Unit 1 Turbine Driven AFW Pump (1P-29) Service Water Supply Valve (lAF-4006) can lose control due to a fire within fire areas AOl-CS and AOl-B. This pump and valve are credited for safe shutdown for these two areas. Manual action would be necessary to take manual local control of this valve to provide continued suction for the AFW pump after drain down of the CST.
Since the missing procedural guidance may have resulted in the omission of safety significant operator actions (which are credited in the Safe Shutdown Analysis) had a fire occurred while FOP 1.2, Revision 6 through 9 were in effect, this condition is being reported pursuant to 10 CFR 50.73(a)(2)(ii)(B) as a condition that resulted in the plant being in an unanalyzed condition that significantly degraded plant safety.
Safety Significance
The safety significance of this condition is continuing to be evaluated. NMC will provide a supplement to this report if the result of the evaluation indicates more than very low safety significance.
Cause
NMC conducted a Root Cause Evaluation on this condition. This evaluation concluded this event occurred because superceded data was used when developing Revision 6 to FOP 1.2. The use of superceded data was caused by human performance error in that the data being used for procedure revision was not verified to be current. Revision 5 of FOP 1.2, which contained correct information, was not used for developing the revised version. Additionally, the change process for preparation of FOP 1.2 Revision 6, lacked sufficient independent review in that the same individual both prepared and reviewed the revision. Time pressure likely contributed to this condition.
Corrective Action
FOP 1.2 was revised to include the inadvertently omitted safe shutdown equipment. An extent of condition review was conducted. A number of other changes between FOP 1.2 Revision 5 and Revision 6 were identified which had not been properly documented. These changes were evaluated as not safety significant.
The Root Cause Evaluation also recommended that uncontrolled copies of the database containing the superceded data used during this event be deleted. Appropriate actions have been taken to ensure that only current and validated Safe Shutdown Analysis Data are available for use.
Previous Similar Events
A review of recent LERs (past three years) identified no similar previous events.
NRC FORM 366 U.S. NUCLEAR REGULATORY APPROVED BY OMB NO. 3150-0104 EXPIRES 7-31-2004 (7-2001)
COMMISSION Estimated burden per response to complywith this mandatoryinformation collection request:
50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />. Reported lessons learned are incorporated Into the licensing process and fed back to Industry Send comments regarding burden estimate to the Records Management Branch (T-ES, US.
uclarReglatry ommss~n.Washingon, DC 20555-0001, orbyienteet e-LICENSEE EVENT REPORT (LER) mail tof bSn.
N an tothef Desk Officer. Office "ofInformation and Regulatory Affairs.
(See reverse for required number of EO-02(3001).ficofMnagement and Budget. Washington. DC 20503. Ifla digits/characters for each block) meandisplay a currently valid 0MB control number, the NRC may not conduct or sponsor, and a person Is not required to respond to, the FACILTTY NAUF f1 I no KFT NIIURFR (21 PAr.EtI POINT BEACH NUCLEAR PLANT UNIT 1 05000266 1 OF 4
TITLE (4)
UNANALYZED CONDITION DUE TO DEFICIENCY IN APPENDIX R SAFE SHUTDOWN STRATEGY FOR CHARGING PUMP CAPABILITY EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
YEARISEQUENTI REFACILITY NAME DOCKET NUMBER MO DAY YEAR YEAR NUMBER NO MO DAY YEAR PT BEACH UNIT 2 05000301 FACILITY NAME DOCKET NUMBER 06 07 2005 2005 -
002.
00 08 08 2005 OPERATING THIS REPORT IS SUBMITTED PURSUANTTO THE REQUIREMENTS OF 10 CR : (Check all that apply) (11)
MODE (9) 1/6 20.2201 (b)
_ 20.2203(a)(3)(ii)
X 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)
POWER
_ 20.2201 (d) 20.2203(a)(4)
_ 50.73(a)(2)(iii) 50.73(a)(2)(x)
LEVEL (10) 100/0 _ 20.2203(a)(1) 50.36(c)(1)(i)(A)
_ 50.73(a)(2)(iv)(A) 73.71(a)(4) 20.2203(a)(2)(i) 50.36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71(a)(5) 20.2203(a)(2)(i) 50.36(c)(2) 50.73(a)(2)(v)(B)
OTHER
- - Specif In Abstract below or In 20.2203(a)(2)(iii)
_ 50.46(a)(3)(i) 50.73(a)(2)(v)(C)
NRIC Form 366A 20.2203(a)(2)(iv) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D) 20.2203(a)(2)(v) 50.73(a)(2)(i)(B)
_50.73(a)(2)(vli) 20.2203(a)(2)(vi) 50.73(a)(2)(i)(C)
_ 50.73(a)(2)(vili)(A) l
- _e_-
20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(B) -
=UCENSEE CONTACT FOR THIS LER (12)
NAME TELEPHONE NUMBER (Include Area Code)
J. Masterlark I
920-755-7591 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
MANU-REPORTABLE MANUS REPORTABLE
CAUSE
SYSTEM COMPONENT FACTURER TO EPIX
CAUSE
SYSTEM COMPONENT FACTURER TO EPIX SUPPLEMENTAL REPORT EXPECTED (14)
EXTPCTED DAY YEAR SUBMISSION YES (If yes, complete EXPECTED SUBMISSION DATE).
I X lNO DATE (15) l l
ABSTRACT (Umit to 1400 spaces, L.e., approximately 15 single-spaced typewrItten lines) (16)
On April 8, 2005, NMC staff identified a potential deficiency in the Point Beach Appendix R Safe Shutdown Strategy. A review of the physical routing of Unit I Charging Pump 2C (1 P-2C) control cables indicated that those control cables located within Fire Area A06 would be damaged and prevent remote operation from the control room following postulated fire damage to these control cables. Fire Organizational Plan (FOP) 1.2 was revised on April 15, 2005, to ensure adequate manual actions are in place to establish and maintain Unit 1 charging pump capability and coolant pump seal cooling.
On June 7, 2005, a continuing review determined that this condition affected available charging pump capability. The condition could have resulted in losing the availability of all but a single charging pump operating at slow speed, which would not provide sufficient seal cooling to the reactor coolant pump (RCP),
thereby degrading the level of plant safety.
On April 28, 2005, a similar issue was documented for the Unit 2 charging pumps. Specifically, neither FOP 1.2, nor the safe shutdown Analysis Compliance Strategies provide adequate guidance for manual actions necessary to restart the charging pumps. This is necessary to ensure adequate RCP seal cooling is established or maintained. FOP 1.2 was revised on May 9, 2005, to ensure adequate manual actions are in place to establish and maintain Unit 2 charging pump capability and reactor coolant seal cooling.U.S. NUCLEAR REGULATORY COMMISSION (7-2001)
LICENSEE EVEwT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1)
DOCKET NUMBER (2)
LER NUMBER (6)
PAGE (3)
YEAR SEQUENTIAL REVISION Point Beach Nuclear Plant Unit 1 05000266 NUMBER NUMBER 2 of 4 2005 002 00 TEXT (If nore space Is required, use additional copies of NRC Form 366A) (17)
Event Description
On April 8, 2005, NMC staff identified a potential deficiency in the Point Beach Appendix R Safe Shutdown Strategy. Problems were identified with the Safe Shutdown Strategy with respect to the use of Unit 1 Charging Pumps' for a fire in Fire Area A06, I B32 motor control center (MCC2) area.
A review of the control cables3 associated with charging pump I P-2C indicated that cables were located within Fire Area A06. If a fire occurred in this area and damaged the control cables, the ability to start the pump from the control room would be lost.
Fire Organization Plan, FOP 1.2 (Revision 6) for fire area A06 stated the strategy that should be used if reactor coolant pump' (RCP) seal injection flow is lost for 10 minutes. Specifically, it states to ensure seal injection remains isolated. This is in conflict with the Safe Shutdown Analysis, which states that RCP seal cooling must be restored in a timely manner. If a prolonged loss of seal cooling occurs, the RCP seals could fail, resulted in leakage in excess of makeup capability.
FOP 1.2 Revision 7 was issued on April 15, 2005, to direct the manuai actions necessary to maintain Unit 1 charging pump capability and coolant pump seal cooling.
On April 28, 2005, a similar issue was documented for the Unit 2 charging pumps. Specifically, neither FOP 1.2, nor the Safe Shutdown Analysis Compliance Strategies, provided adequate guidance for manual actions necessary to restart these pumps to ensure adequate RCP seal cooling is established.
FOP 1.2 was revised on May 9, 2005 to revision 8, to ensure adequate manual actions are in place to maintair and establish Unit 2 charging pump capability and reactor coolant pump seal cooling.
On June 7, 2005, a continuing review of further information related to this condition, determined that the available charging pump capability was affected. The system would not provide sufficient reactor coolant pump seal cooling, thereby degrading the level of plant safety.
Event Analysis
Unit 1:
The Safe Shutdown Analysis for this area discusses a problem where control and power cables for all three (3) Unit 1 charging pumps are routed within the fire area. An exemption was provided by the NRC, based upon adequate separation of the power cables between the A train charging pumps (1 P-2A and 1 P-2B) and the B train pump (1 P-2C). For a fire in the vicinity of motor control center 1 B32, charging pump 1 P-2C is credited, since its associated power cables have adequate separation. However, control cables could be damaged resulting in a loss of speed control. With the loss of control cables, the pump will continue to run at minimum speed, which would be adequate for normal make-up when the RCP seals are not challenged.
The Safe Shutdown Analysis stresses the importance of ensuring continuity of charging, such that the seals are protected from sustained loss of cooling. The coping strategy, contained within the Safe Shutdown Analysis indicates that no manual actions are required outside the control room if control power is lost.
I (EIIS Component Identifier P) 2 (EIIS Component Identifier: MCC)
I (EIIS Component Identifier: CBL) 4 (EIIS Component Identifier: P)
- - U.S. NUCLEAR REGULATORY COMMISSION (7-2001)
LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION FACILITY NAME (1)
OCKET NUMBER (2)
LER NUMBER (61 PAGE (3)
YEAR SEQUENTIAL I REVISION Point Beach Nuclear Plant Unit 1 05000266 NUMBER lINUMBER 3 of 4 2005 002 00 TEXT (if more space Is requited, use additional copies of NRC Form 366A) (17)
A review of the control cables associated with 1 P-2C, indicates that cables are located within Fire Area A06.
If damaged by fire, the pump would not be able to be started from the control room. The Safe Shutdown Analysis did not identify the control cables as required for safe shutdown, and the circuit analysis did not consider the impact of fire damage on the associated control circuit. There are three reasons that the pump may not be running and require a start. First, the pump could be in standby as part of normal pump line-up.
Second, the pump could be tripped on under voltage. Third, the pump could trip due to intra-cable or inter-cable shorts in the control cable. A loss of off-site power is assumed for this scenario. A review of power cables in this fire area confirm that off-site power to Unit 1 could be lost if a fire occurred.
FOP 1.2 (Revision 6) for fire area A06 stated the strategy that should be used if RCP seal injection flow is lost for 10 minutes. Specifically, it requires that seal injection remain isolated. This is in conflict with the Safe Shutdown Analysis, which states that RCP seal cooling must be restored in a timely manner to ensure make-up capability would not be lost as a result of failure of the RCP seals.
Unit 2:
The Safe Shutdown Analysis for Fire Area Al 5 (Unit 2 B32 MCC Room) credits the use of the Unit 2 charging pumps. Specifically, a fire in the east side of this Fire Area credits the use of either charging pump 2P-2A or 2P-2B. In this portion of the fire area, power and control power to charging pump 2P-2C is affected and the pump is not credited. The power cables for 2P-2A and 2P-2B are routed through the western portion of the fire area (in the vicinity of 2B-32). An exemption is provided for this separation to ensure availability of the 2P-2A and/or 2P-2B in the event of a fire in the eastern portion of the room. It is also recognized that the fire would affect the speed control of 2P-2A and 2P-2B. For this reason it is important to minimize the interruption of charging flow to RCP seal cooling. If seal cooling would be lost for too long a duration, the resulting leakage could exceed the capability of charging pump(s) operating at minimum flow.
Through a physical walk down of cable routing, it was confirmed that at least one of the control power circuit cables for each of the Unit 2 'A' Train Charging Pumps is routed through the eastern portion of the fire area.
Fire damage to the control cables in this area could result in a total loss of the control circuit.
Neither FOP 1.2 nor the Safe Shutdown Analysis Compliance Strategies provide adequate guidance of manual actions necessary to restart these pumps as necessary to ensure adequate RCP cooling.
Safety Significance
The plant maintains administrative controls for the introduction of combustible materials and ignition sources to limit the probability of a fire. These areas are also provided with automatic fire detection and suppression systems. The safety significance of this condition continues to be evaluated. Based on these administrative controls and fire protection features, NMC considers the safety significance of this issue to be very low.
NMC will provide a supplement to this LER if the result of the final evaluation indicates more than very low
safety significance
I(7-2001)
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
TEXT CONTINUATION Point Beach Nuclear Plant Unit 1 TEXT (I more space s required, use additional copies of NRC Fon'n 366A) (17)
Cause
The cause of this condition was a result of only considering the impact of control circuit damage on the speed control of an operating charging pump, and not the manual actions required to operate the pump should the pump be in standby or tripped due to under voltage or short circuit.
Corrective Action
Completed:
- Implemented twice per shift compensatory fire watches for Fire Area A06 until resolution of manual actions is complete.
- Revised FOP 1.2 with selected method of recovery and remove option to isolate RCP seal cooling from FOP 1.2, Fire Area A-06.
- Implemented a Mode 4 hold during the Unit 2 outage until FOP 1.2 was revised.
- Revised FOP 1.2 with selected method of recovery and removed options to isolate seal cooling from FOP 1.2 for Fire Area A-1 5.
Planned:
- Evaluate potential manual actions to resolve this issue.
- Update the Safe Shutdown Analysis with selected method of recovery.
Previous Similar Events
A review of recent LERs (past three years) identified one event that involved improper routing of electrical cables resulting in inadequate train separation.
LER Number Title 266-2002-002-00 Unit 1 A-Train Reactor Protection Cable Routed in B-Train Cable Trays