NL-05-1151, Supplemental Information to the Fourth 10-Year Interval IST Program Update Submittal
| ML051810234 | |
| Person / Time | |
|---|---|
| Site: | Hatch  |
| Issue date: | 06/28/2005 |
| From: | Sumner H Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-05-1151, NUREG-1482 | |
| Download: ML051810234 (3) | |
Text
.1 H. L Sumner, Jr.
Vice President Hatch Project Southern Nuclear Operating Company. Inc.
Post Office Box 1295 Birmingham, Alabama 35201 Tel 205.992.7279 SOUTHERN A COMPANY Energy to Serve Your World' NL-05-1 151 June 28, 2005 Docket Nos.:
50-321 50-366 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Edwin I. Hatch Nuclear Plant Supplemental Information to the Fourth 10-Year Interval IST Program Update Submittal Ladies and Gentlemen:
By letter dated April 20, 2005 Southern Nuclear Operating Company (SNC) submitted IST relief request RR-P-1 which proposed quarterly Group 'A' testing for all pumps in the IST Program in lieu of performing a Group 'A' or Group 'B' test, as applicable, quarterly and a Comprehensive Pump Test (CPT) biennially. This is discussed in Issue I below. Also in the April 20, 2005 letter, SNC informed the NRC of its intent to use the guidance in NUREG 1482, Revision I and phase in implementation of the IST Program Update. This is discussed in Issue 2. The purpose of this submittal is to provide supplemental information to clarify the April 20, 2005 submittal.
Issue I SNC understands that the purpose for addition of the CPT in the OM Code was to ensure that each pump is tested at a flow rate adequate for determination of operational readiness and for monitoring degradation. Previous editions/addenda of the ASME Section XI and OM Codes did not require pump ]ST at substantial flow rates and allowed for testing at low flow conditions in which pump degradation may not be detected. HNP is a BWR and initial plant design included full flow test loops for all 1ST pumps. SNC believes that Group 'A' testing on all IST pumps on a quarterly basis provides an acceptable level of quality and safety because:
Every pump in the IST program is currently tested at or near design flow rate on a quarterly frequency, and this testing would be continued in the 4 th interval.
Therefore, the flow rate for the proposed Group 'A' test is equivalent to that required by the CPT.
Most HNP IST systems are maintained in standby and the pumps in the system would be classified as Group 'B' pumps. Group 'B' testing requires no trending of hydraulic parameters or vibration monitoring. Group 'A' testing on a quarterly frequency should provide a better means of determining operational readiness and monitoring for degradation because 8 data points every 2 years provides for a 61q
U. S. Nuclear Regulatory Commission NL-05-1 151 Page 2 better trend of the hydraulic parameters and vibration than I data point every 2 years.
- The OM Code Committee is currently considering a revision to allow performing this type testing in lieu of performing a comprehensive pump test every 2 years (i.e., quarterly Group 'A' test at a flow rate equivalent to the CPT required flow rate).
- The more stringent acceptance criteria of the CPT does not seem warranted because extensive historical IST data at HNP, performed at high pump flow rates, confirms the ability to determine operational readiness and monitor degradation allowing adequate time for compensatory or corrective actions prior to the pumps becoming inoperable.
Issue 2 SNC intends to use the guidance included in NUREG-1482, Revision 1, paragraph 3.3.3 for implementation of the updated IST Program. The approach taken by SNC is the same approach taken in 3rd interval Relief Request RR-G-3. This Relief Request was authorized in a SER dated August 29, 1995.
In accordance with the guidance provided in NUREG 1482, Revision 1, Section 3.3.3, the NRC staff recommended that before beginning the first tests during the new interval, licensees should revise the implementing procedures according to the appropriate requirements. The basis for this NRC staff recommendation is that when a licensee updates their IST Program to a revised edition and addenda of the code, the NRC staff recognizes that changes might be completed over a period of time to allow for adequate review and approval. However, the staff recommends completing the procedural revisions in a timely manner. SNC has chosen to provide advance notification of the intention to use the guidance provided in NUREG 1482, Revision 1. The information below is intended to clarify the SNC proposal for a phased-in implementation per NUREG-1482, Revision 1, Section 3.3.3.
Each system has an IST valve test procedure and a pump test procedure. The total number of IST procedures is approximately 100 (2-Units).
- SNC proposes to update procedures by system for the new interval. A system will be selected and the related IST procedures (pump and valve) will be updated to meet the new IST Program requirements. Then another system will be selected and the process repeated until all procedures have been updated.
All power operated valves that can only be tested during a plant shutdown are included in a single procedure for each unit. These procedures will be updated in advance of the next outage in the new interval.
U. S. Nuclear Regulatory Commission NL-05-1 151 Page 3
- The OM Code, 2001 edition through 2003 addenda, ISTA-3120(d), allows the extension of an interval by as much as I -year. However, SNC did not consider phase-in implementation to be an extension of the interval. SNC interpreted the NRC Guidance to allow the previous IST requirements to be phased out over time as they are replaced by the updated program requirements. Therefore, testing of certain pumps and valves per the updated program would begin when the new interval begins, but would be continued under the previous program requirements for the remaining components.
System surveillance procedures would be updated and made effective in a progressive manner until all testing was in compliance with the updated program requirements. The phase out of the previous interval IST and phase in of the updated program IST would continue through the first year. SNC will be in complete compliance with the updated version of the Code prior to December 31, 2006.
- This alternative allows SNC to use lessons learned throughout the procedure revision process.
This letter contains no NRC commitments. If you have any questions, please advise.
- Sinceel, H. L. Sumner, Jr.
HLS/IFL/daj cc:
Southern Nuclear Operating Company Mr. J. T. Gasser, Executive Vice President Mr. G. R. Frederick, General Manager - Plant Hatch RTYPE: CHAO2.004 U. S. Nuclear Regulatory Commission Dr. W. D. Travers, Regional Administrator Mr. C. Gratton, NRR Project Manager - Hatch Mr. D. S. Simpkins, Senior Resident Inspector - Hatch