ML031220301
| ML031220301 | |
| Person / Time | |
|---|---|
| Site: | Watts Bar  |
| Issue date: | 05/01/2003 |
| From: | NRC/NRR/DLPM |
| To: | |
| Jabbour K, NRR/DLPM, 415-1496 | |
| References | |
| TAC MB8382 | |
| Download: ML031220301 (3) | |
Text
ECCS -
Operating 3.5.2 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.5.2.1 Verify the following valves are in the 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> listed position with power to the valve operator removed.
Number Position Function FCV-63-1 Open RHR Supply FCV-63-22 Open SIS Discharge SR 3.5.2.2 Verify each ECCS manual, power operated, 31 days and automatic valve in the flow path, that is not locked, sealed, or otherwise secured in position, is in the correct position.
SR 3.5.2.3 Verify ECCS piping is full of water.
31 days NOTE:
Surveillance performance not required for safety injection hot leg injection lines until start up from the Fall 2003 refueling outage.
SR 3.5.2.4 Verify each ECCS pump's developed head In accordance at the test flow point is greater than with the or equal to the required developed head.
Inservice Testing Program SR 3.5.2.5 Verify each ECCS automatic valve in the 18 months flow path that is not locked, sealed, or otherwise secured in position, actuates to the correct position on an actual or simulated actuation signal.
SR 3.5.2.6 Verify each ECCS pump starts 18 months automatically on an actual or simulated actuation signal.
(continued)
Watts Bar-Unit 1 3.5-5 Amendment 43
ECCS -
Operating B 3.5.2 BASES SURVEILLANCE SR 3.5.2.3 (continued)
REQUIREMENTS ensures that the system will perform properly, injecting its full capacity into the RCS upon demand.
This will also prevent water hammer, pump cavitation, and pumping of noncondensible gas (e.g., air, nitrogen, or hydrogen) into the reactor vessel following an SI signal or during shutdown cooling.
The 31 day Frequency takes into consideration the gradual nature of gas accumulation in the ECCS piping and the procedural controls governing system operation.
A note is added to the FREQUENCY that surveillance performance is not required for safety injection hot leg injection lines until startup from the Fall 2003 Refueling Outage.
(Ref. 7)
SR 3.5.2.4 Periodic surveillance testing of ECCS pumps to detect gross degradation caused by impeller structural damage or other hydraulic component problems is required by Section XI of the ASME Code.
This type of testing may be accomplished by measuring the pump developed head at only one point of the pump characteristic curve.
This verifies both that the measured performance is within an acceptable tolerance of the original pump baseline performance and that the performance at the test flow is greater than or equal to the performance assumed in the plant safety analysis.
SRs are specified in the Inservice Testing Program, which encompassesSection XI of the ASME Code.
Section XI of the ASME Code provides the activities and Frequencies necessary to satisfy the requirements.
SR 3.5.2.5 and SR 3.5.2.6 These Surveillances demonstrate that each automatic ECCS valve actuates to the required position on an actual or simulated SI signal and that each ECCS pump starts on receipt of an actual or simulated SI signal.
This Surveillance is not required for valves that are locked, sealed, or otherwise secured in the required position under administrative control.
The 18 month Frequency is based on the need to perform these Surveillances under the conditions that apply during a plant outage and the potential for unplanned plant transients if the Surveillances were performed with the reactor at power.
The 18 month Frequency is also acceptable based on consideration of the design reliability (and confirming operating experience) of the equipment.
The actuation logic is tested as part of ESF (continued)
Watts Bar-Unit 1 B 3.5-18 Amendment 43
ECCS -
Operating B 3.5.2 BASES SURVEILLANCE SR 3.5.2.5 and 3.5.2.6 (continued)
REQUIREMENTS Actuation System testing, and equipment performance is monitored as part of the Inservice Testing Program.
SR 3.5.2.7 Realignment of valves in the flow path on an SI signal is necessary for proper ECCS performance.
These valves are secured in a throttled position for restricted flow to a ruptured cold leg, ensuring that the other cold legs receive at least the required minimum flow.
The 18 month Frequency is based on the same reasons as those stated in SR 3.5.2.5 and SR 3.5.2.6.
SR 3.5.2.8 Periodic inspections of the containment sump suction inlet ensure that it is unrestricted and stays in proper operating condition.
The 18 month Frequency is based on the need to perform this Surveillance under the conditions that apply during a plant outage, on the need to have access to the location, and because of the potential for an unplanned transient if the Surveillance were performed with the reactor at power.
This Frequency has been found to be sufficient to detect abnormal degradation and is confirmed by operating experience.
REFERENCES
- 1.
Title 10, Code of Federal Regulations, Part 50, Appendix A, General Design Criterion 35, "Emergency Core Cooling System."
- 2.
Title 10, Code of Federal Regulations, Part 50.46, "Acceptance Criteria for Emergency Core Cooling Systems for Light Water Nuclear Power Plant."
- 3.
Watts Bar FSAR, Section 6.3, "Emergency Core Cooling System."
- 4.
FSAR Bar FSAR, Section 15.0, "Accident Analysis.'
- 5.
NRC Memorandum to V. Stello, Jr., from R.L. Baer,
'Recommended Interim Revisions to LCOs for ECCS Components," December 1, 1975.
- 6.
IE Information Notice No. 87-01, "RHR Valve Misalignment Causes Degradation of ECCS in PWRs,"
January 6, 1987.
- 7.
WBN License Amendment Request WBN-TS-03-11 dated April 8, 2003.
Watts Bar-Unit 1 B 3.5-19 Amendment 43