ML101680440
| ML101680440 | |
| Person / Time | |
|---|---|
| Site: | Limerick  |
| Issue date: | 06/21/2010 |
| From: | Peter Bamford Plant Licensing Branch 1 |
| To: | Chernoff H Plant Licensing Branch 1 |
| Bamford, Peter J., NRR/DORL 415-2833 | |
| References | |
| TAC ME3589, TAC ME3590, TAC ME3591, TAC ME3592 | |
| Download: ML101680440 (5) | |
Text
June 21, 2010 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM:
Peter Bamford, Project Manager /RA/
Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
LIMERICK GENERATING STATION, UNITS 1 AND 2 - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING MEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATE (TAC NOS. ME3589, ME3590, ME3591 and ME3592)
The attached draft request for additional information (RAI) was transmitted by electronic transmission on June 21, 2010, to Mr. Kevin Borton, at Exelon Generation Company, LLC (Exelon). This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call (if needed) with Exelon in order to clarify the licensees submittal. The draft RAI is related to Exelons submittal dated March 25, 2010, regarding Limerick Generating Station, Units 1 and 2, Measurement Uncertainty Recapture Power Uprate. The draft questions were sent to ensure that they were understandable, the regulatory basis was clear, and to determine if the information was previously docketed. Additionally, review of the draft RAI would allow Exelon to evaluate and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not represent an NRC staff position.
Docket Nos. 50-352 and 50-353
Enclosure:
As stated
June 21, 2010 MEMORANDUM TO: Harold K. Chernoff, Chief Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation FROM:
Peter Bamford, Project Manager /RA/
Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
SUBJECT:
LIMERICK GENERATING STATION, UNITS 1 AND 2 - ELECTRONIC TRANSMISSION, DRAFT REQUEST FOR ADDITIONAL INFORMATION REGARDING MEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATE (TAC NOS. ME3589, ME3590, ME3591 and ME3592)
The attached draft request for additional information (RAI) was transmitted by electronic transmission on June 21, 2010, to Mr. Kevin Borton, at Exelon Generation Company, LLC (Exelon). This draft RAI was transmitted to facilitate the technical review being conducted by the Nuclear Regulatory Commission (NRC) staff and to support a conference call (if needed) with Exelon in order to clarify the licensees submittal. The draft RAI is related to Exelons submittal dated March 25, 2010, regarding Limerick Generating Station, Units 1 and 2, Measurement Uncertainty Recapture Power Uprate. The draft questions were sent to ensure that they were understandable, the regulatory basis was clear, and to determine if the information was previously docketed. Additionally, review of the draft RAI would allow Exelon to evaluate and agree upon a schedule to respond to the RAI. This memorandum and the attachment do not represent an NRC staff position.
Docket Nos. 50-352 and 50-353
Enclosure:
As stated DISTRIBUTION:
Public RidsNrrPMLimerick LPL1-2 R/F Accession No.: ML101680440
- via email OFFICE LPL1-2/PM IHPB/BC NAME PBamford UShoop*
DATE 6/21/10 06/11/2010 OFFICIAL RECORD COPY
DRAFT Enclosure REQUEST FOR ADDITIONAL INFORMATION LIMERICK GENERATING STATION, UNITS 1 AND 2 MEASUREMENT UNCERTAINTY RECAPTURE POWER UPRATE REQUEST DOCKET NOS. 50-352 AND 50-353 By letter dated March 25, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML100850380), Exelon Generation Company, LLC (Exelon, the licensee) submitted a license amendment request (LAR) proposing to revise the operating license and technical specifications (TSs) for Limerick Generating Station (LGS), Units 1 and 2.
This LAR proposes to implement an increase of approximately 1.65% in rated thermal power from the currently licensed thermal power limit of 3458 megawatts thermal. The increase would be based on the improved thermal power measurement accuracy, which would be achieved through the utilization of the Cameron International (formerly Caldon) CheckPlusTM leading edge flowmeter (LEFM) ultrasonic flow measurement instrumentation. The application also proposes a modification to the standby liquid control system (SLCS). The Nuclear Regulatory Commission (NRC) staff has been reviewing the submittal and has determined that additional information is needed to complete its review.
(1) Attachment 1 to the LAR letter, dated March 25, 2010, states that the scope and content of the evaluations performed and described in the LAR are consistent with the guidance of NRC Regulatory Issue Summary (RIS) 2002-03, Guidance on the Content of Measurement Uncertainty Recapture Power Uprate Applications. RIS 2002-03, Attachment I,Section VII.2.A requests:
A statement confirming that the license has identified all modifications associated with the proposed power uprate with respect to the following aspects of plant operations that are necessary to ensure that changes in operator actions do not adversely affect defense in depth or safety margins:
A.
emergency and abnormal operating procedures In the submittal dated March 25, 2010, attachment 61, section 10.9, emergency operating procedures are discussed. However, there is no mention of required changes to the current abnormal operating procedures. Please provide, if any, a summary of the required changes for the abnormal operating procedures.
1 Attachment 6 is a report by General Electric (GE)-Hitachi Nuclear Energy, NEDC-33484P, titled Safety Analysis Report for Limerick Generating Station Units 1 and 2 Thermal Power Optimization, Revision 0, dated March 2010. A non-proprietary version of this report (NEDO-33484, same title) is available at ADAMS Accession No. ML100850403.
DRAFT (2)Section VII.4 of attachment 1 to RIS 2002-03 requests: A statement confirming licensee intent to revise existing plant operating procedures related to temporary operation above full steady-state licensed power levels to reduce the magnitude of the allowed deviation from the licensed power level. The magnitude should be reduced from the pre-power uprate value of 2 percent to a lower value corresponding to the uncertainty in power level credited by the proposed power uprate application. In the submittal, dated March 25, 2010, attachment 1, section 3.2.6, Exelon states that LGS procedure GP-5 section 3.0, notes 5 and 6 provides guidance for monitoring and controlling reactor power consistent with Nuclear Energy Institute (NEI) guidance2.
However, this information is not available in the submittal. Please provide procedure GP-5, or the information contained therein.
(3) According to the LGS Updated Final Safety Evaluation Report, section 3.1, page 3.1-23, the SLCS provides an independent backup system for reactivity control in accordance with the requirements of 10 CFR 50, Appendix A, Criterion 26, Reactivity control system redundancy and capability. In order to assess the reliability of the SLCS in the proposed revised configuration as specified in Criterion 26, the NRC staff plans to use NUREG-1764, Guidance on the Review of Changes to Human Actions. NUREG-1764 specifies levels of review for generic human actions that are considered risk-important.
According to the guidance, a modification to SLCS initiation requires a Level 1 review.
Based on this guidance, the following information is needed:
- a. Describe the function allocation methodology that was used to allocate safety functions and how the role of personnel takes advantage of human strengths and avoids human weaknesses.
- b. Describe how the modification was integrated with the probabilistic risk assessment and risk analysis.
- c. Describe how the modification addresses operator task requirements and system requirements.
- d. Describe the alarms, displays and controls needed for the operator to operate the SLCS system with the proposed switch alignment.
- e. Describe how the modification will be incorporated into operator training.
- f. Describe how the normal, abnormal, and emergency operating procedures will be modified to support this change.
- g. Describe the performance tests used to determine whether the modification meets performance requirements and acceptably supports safe operation of the plant.
(4) According to the LAR, Attachment 1, section 3.5.2, regarding the TS implications of an improper SLCS switch alignment of the C pump, the following is stated: For the condition in which three pumps are aligned for automatic operation, action statement b applies, and requires that the system shall be restored to operable status [less than 2 The referenced NEI guidance is titled NEI Position Statement - Guidance to Licensees on Complying with the Licensed Power Limit, dated 06/12/2008 (ADAMS Accession No. ML081750537). The NEI guidance was endorsed by the NRC staff via RIS 2007-21, Adherence to Licensed Power Limits, Revision 1, dated February 9, 2009 (ADAMS Accession No. ML090220365). The associated NRC safety evaluation for the endorsement of the NEI guidance may be found at ADAMS Accession No. ML082690105.
DRAFT three pumps lined up for automatic operation] within eight hours or be in hot shutdown within the following twelve hours. Since having three pumps lined up for automatic operation would lead to the entire system being placed in a limiting condition for operation, the provisions of 10 CFR 50.36(c)(3) require that an appropriate surveillance be in place to assure SLCS system operability. No such surveillance was proposed in the LAR. Please provide an amended application with an appropriate surveillance, or provide a justification as to why no corresponding surveillance requirement was proposed in the LAR regarding the switch position(s).