GO2-09-157, Response to Request for Additional Information Re Generic Letter 2008-01
| ML093520382 | |
| Person / Time | |
|---|---|
| Site: | Columbia  |
| Issue date: | 12/09/2009 |
| From: | Gambhir S Energy Northwest |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| GL-08-001, GO2-09-157 | |
| Download: ML093520382 (5) | |
Text
Sudesh K. Gambhir EVice President, Technical Services ENERGYP.O.
NORTHW EST. Box 968, PE04 Richland, WA 99352-0968 Ph. 509.377.83131 F. 509.377.2354 sgambhir@ energy-northwest.com December 9, 2009 G02-09-157 10 CFR 50.54(f)
U. S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852
(
Subject:
COLUMBIA GENERATING STATION, DOCKET NO. 50-397 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01
References:
- 1. Letter G02-08-141, dated October 8, 2008, SK Gambhir (Energy Northwest) to NRC, "Nine-Month Response to NRC Generic Letter 2008-01, 'Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems"'
- 2. Letter G02-09-132, dated September 21, 2009, SK Gambhir (Energy Northwest) to NRC, "Supplemental (Post-Outage) Response to NRC Generic Letter 2008-01"
- 3. E-mail dated October 29, 2009, NJ DiFrancesco (NRC) to MC Humphreys (Energy Northwest), "NRC Request for Additional Information, Re: Generic Letter 2008-01, "Managing Gas Accumulation in Emergency Core Cooling; Decay Heat Removal, and Containment Spray Systems" (TAC No. MD7812)"
Dear Sir or Madam:
As requested in Reference 3,; Energy Northwest has provided responses to the requests for additional information (RAIs) that the NRC staff has determined to be necessary to complete their evaluation of Energy Northwest's responses to Generic Letter 2008-01 (References 1 and 2). Energy Northwest's responses to the RAIs are provided in the attachment to this letter.
There are no new commitments being made to the NRC by this letter beyond those previously referenced by Energy Northwest in Reference 1.. If you have any questions, please contact MC Humphreys, Licensing Supervisor, at (509) 377-4025.
-4v3q
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Page 2 I declare under penalty of perjury that the foregoing is true and correct. Executed on the date of this letter.
R~ectfully, Vice President, Technical Services Attachment cc: EE Collins, Jr. - NRC RIV NJ DiFrancesco - NRC NRR NRC Senior Resident Inspector/988C WA Horin -Winston & Strawn RN Sherman - BPA/1 399
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Attachment Page 1 of 3 NRC Request #1 Summarize Energy Northwest's procedural approach to monitoring pump operation in all modes. Specifically, include provisions for specialized monitoring of appropriate plant parameters during shutdown operation, including, for instance, control of reactor vessel water level at Columbia Generating Station.
Energy Northwest Response The procedural approaches for monitoring Emergency Core Cooling System (ECCS) pump operation are similar for both operating and shutdown modes and include all of the following:
a) A Control Room Log procedure that directs Control Room Operators to monitor the following system parameters and conditions:
- Reactor vessel water level is monitored and recorded hourly. Levels aIre maintained sufficiently above Engineered Safety Feature (ESF) actuation setpoints.
- Core flow is monitored while in shutdown cooling mode and recorded once per shift.
0 Each required operable ECCS sub-system is verified to be in a normal standby alignment once per shift.
b) Surveillance procedures are used by Control Room and Equipment Operators to verify system parameters as follows:
- The level in Condensate Storage Tanks (CSTs) is verified to be above the minimum required level once per shift.
- The level in the Suppression Pool is verified to be above the minimum required level at least once per day.
0 Each operable ECCS pump discharge is verified to be sufficiently filled with water monthly by opening system high point vent(s) to vent any air from the system. If any air is discovered in an ECCS system, a Condition Report is written to evaluate system operability and potential cause for the gas.
- ECCS discharge line pressure retention is verified once every 12 months., This ensures that, assuming a loss of the associated discharge line keep-fill pump, the discharge lines will remain full of water during an accident or Appendix R fire until the main ECCS pump is either automatically or manually started.
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Attachment Page 2 of 3 c) Alarm Response procedures are used by Control Room staff to verify/restore system integrity for any of the following conditions:
0 "Low level" in the Reactor Pressure Vessel (RPV)
- "Low level" in the CSTs.
- "Low discharge pressure" on all ECCS pumps. This alarm provides indication of keep-fill system malfunctions.
- "Low suction pressure" on the High Pressure Core Spray (HPCS) pump. The HPCS pump is normally aligned to take suction from the CSTs. This alarm provides indication of low CST supply (level) to the suction of the HPCS pump.
0 "High discharge pressure" on Low Pressure Coolant Injection (LPCI) and Low Pressure Core Spray (LPCS) systems. This alarm provides indication of leakage past injection. isolation valves that could lead to steam voiding in the discharge piping.
0 "High suction pressure" on the Residual Heat Removal (RHR) pump.
This alarm provides an indication of leakage past the reactor pressure vessel isolation valve and potential steam voiding in the suction line of the RHR pumps while the plant is operating at power. In addition, an abnormal operating procedure has been developed to monitor these high suction pressure conditions and address any leakage that might exist.
d) Following maintenance on ECCS systems in which air might be introduced into the systems, procedures provide direction to ensure the applicable ECCS systems are properly filled and vented. Following the system fill, the system is aligned to flow water into the RPV to sweep any potential gases into the RPV. If conditions exist which prohibit RPV injection, then an ultrasonic test (UT) inspection is performed on suspected gaseous collection points to identify any potential voids:
NRC Request #2 Provide a brief discussion of any training that is planned in response to GL 2008-001.
'Energy Northwest Response Operator specific training material has already been developed to address concerns identified in GL 2008-01 as well as Significant Operating Experience Report (SOER) 97-1. This training material covers awareness of the sources and consequences of
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Attachment Page 3 of 3 gas intrusion into water filled safety systems including ECCS. The training was presented to both Licensed and Non-Licensed Operators as part of continuing operator training during the spring of.2008.
Previous to the issuance of the Generic Letter, piping design and break analysis training had been provided to engineering staff. In addition, maintenance training courses had been previously developed to include proper guidance for backfilling instrument lines.
However, regarding future training, Energy Northwest is following the development of industry training recommendations and associated training modules which are expected to be distributed by industry groups in the near future. Once received, Energy Northwest plans to evaluate the material in each of the associated Operations, Engineering, and Maintenance Department training Curriculum Review Committees-for inclusion in applicable training plans.
Text
Sudesh K. Gambhir EVice President, Technical Services ENERGYP.O.
NORTHW EST. Box 968, PE04 Richland, WA 99352-0968 Ph. 509.377.83131 F. 509.377.2354 sgambhir@ energy-northwest.com December 9, 2009 G02-09-157 10 CFR 50.54(f)
U. S. Nuclear Regulatory Commission ATTN: Document Control Desk 11555 Rockville Pike Rockville, MD 20852
(
Subject:
COLUMBIA GENERATING STATION, DOCKET NO. 50-397 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01
References:
- 1. Letter G02-08-141, dated October 8, 2008, SK Gambhir (Energy Northwest) to NRC, "Nine-Month Response to NRC Generic Letter 2008-01, 'Managing Gas Accumulation in Emergency Core Cooling, Decay Heat Removal, and Containment Spray Systems"'
- 2. Letter G02-09-132, dated September 21, 2009, SK Gambhir (Energy Northwest) to NRC, "Supplemental (Post-Outage) Response to NRC Generic Letter 2008-01"
- 3. E-mail dated October 29, 2009, NJ DiFrancesco (NRC) to MC Humphreys (Energy Northwest), "NRC Request for Additional Information, Re: Generic Letter 2008-01, "Managing Gas Accumulation in Emergency Core Cooling; Decay Heat Removal, and Containment Spray Systems" (TAC No. MD7812)"
Dear Sir or Madam:
As requested in Reference 3,; Energy Northwest has provided responses to the requests for additional information (RAIs) that the NRC staff has determined to be necessary to complete their evaluation of Energy Northwest's responses to Generic Letter 2008-01 (References 1 and 2). Energy Northwest's responses to the RAIs are provided in the attachment to this letter.
There are no new commitments being made to the NRC by this letter beyond those previously referenced by Energy Northwest in Reference 1.. If you have any questions, please contact MC Humphreys, Licensing Supervisor, at (509) 377-4025.
-4v3q
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Page 2 I declare under penalty of perjury that the foregoing is true and correct. Executed on the date of this letter.
R~ectfully, Vice President, Technical Services Attachment cc: EE Collins, Jr. - NRC RIV NJ DiFrancesco - NRC NRR NRC Senior Resident Inspector/988C WA Horin -Winston & Strawn RN Sherman - BPA/1 399
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Attachment Page 1 of 3 NRC Request #1 Summarize Energy Northwest's procedural approach to monitoring pump operation in all modes. Specifically, include provisions for specialized monitoring of appropriate plant parameters during shutdown operation, including, for instance, control of reactor vessel water level at Columbia Generating Station.
Energy Northwest Response The procedural approaches for monitoring Emergency Core Cooling System (ECCS) pump operation are similar for both operating and shutdown modes and include all of the following:
a) A Control Room Log procedure that directs Control Room Operators to monitor the following system parameters and conditions:
- Reactor vessel water level is monitored and recorded hourly. Levels aIre maintained sufficiently above Engineered Safety Feature (ESF) actuation setpoints.
- Core flow is monitored while in shutdown cooling mode and recorded once per shift.
0 Each required operable ECCS sub-system is verified to be in a normal standby alignment once per shift.
b) Surveillance procedures are used by Control Room and Equipment Operators to verify system parameters as follows:
- The level in Condensate Storage Tanks (CSTs) is verified to be above the minimum required level once per shift.
- The level in the Suppression Pool is verified to be above the minimum required level at least once per day.
0 Each operable ECCS pump discharge is verified to be sufficiently filled with water monthly by opening system high point vent(s) to vent any air from the system. If any air is discovered in an ECCS system, a Condition Report is written to evaluate system operability and potential cause for the gas.
- ECCS discharge line pressure retention is verified once every 12 months., This ensures that, assuming a loss of the associated discharge line keep-fill pump, the discharge lines will remain full of water during an accident or Appendix R fire until the main ECCS pump is either automatically or manually started.
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Attachment Page 2 of 3 c) Alarm Response procedures are used by Control Room staff to verify/restore system integrity for any of the following conditions:
0 "Low level" in the Reactor Pressure Vessel (RPV)
- "Low level" in the CSTs.
- "Low discharge pressure" on all ECCS pumps. This alarm provides indication of keep-fill system malfunctions.
- "Low suction pressure" on the High Pressure Core Spray (HPCS) pump. The HPCS pump is normally aligned to take suction from the CSTs. This alarm provides indication of low CST supply (level) to the suction of the HPCS pump.
0 "High discharge pressure" on Low Pressure Coolant Injection (LPCI) and Low Pressure Core Spray (LPCS) systems. This alarm provides indication of leakage past injection. isolation valves that could lead to steam voiding in the discharge piping.
0 "High suction pressure" on the Residual Heat Removal (RHR) pump.
This alarm provides an indication of leakage past the reactor pressure vessel isolation valve and potential steam voiding in the suction line of the RHR pumps while the plant is operating at power. In addition, an abnormal operating procedure has been developed to monitor these high suction pressure conditions and address any leakage that might exist.
d) Following maintenance on ECCS systems in which air might be introduced into the systems, procedures provide direction to ensure the applicable ECCS systems are properly filled and vented. Following the system fill, the system is aligned to flow water into the RPV to sweep any potential gases into the RPV. If conditions exist which prohibit RPV injection, then an ultrasonic test (UT) inspection is performed on suspected gaseous collection points to identify any potential voids:
NRC Request #2 Provide a brief discussion of any training that is planned in response to GL 2008-001.
'Energy Northwest Response Operator specific training material has already been developed to address concerns identified in GL 2008-01 as well as Significant Operating Experience Report (SOER) 97-1. This training material covers awareness of the sources and consequences of
RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION RELATED TO GENERIC LETTER 2008-01 Attachment Page 3 of 3 gas intrusion into water filled safety systems including ECCS. The training was presented to both Licensed and Non-Licensed Operators as part of continuing operator training during the spring of.2008.
Previous to the issuance of the Generic Letter, piping design and break analysis training had been provided to engineering staff. In addition, maintenance training courses had been previously developed to include proper guidance for backfilling instrument lines.
However, regarding future training, Energy Northwest is following the development of industry training recommendations and associated training modules which are expected to be distributed by industry groups in the near future. Once received, Energy Northwest plans to evaluate the material in each of the associated Operations, Engineering, and Maintenance Department training Curriculum Review Committees-for inclusion in applicable training plans.