ML12340A256
| ML12340A256 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 12/28/2012 |
| From: | Peter Bamford Plant Licensing Branch 1 |
| To: | Harden P FirstEnergy Nuclear Operating Co |
| Bamford P NRR/DORL/LPL1-2 301-415-2833 | |
| References | |
| TAC ME9144, TAC ME9145 | |
| Download: ML12340A256 (4) | |
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Mr. Paul A. Harden Site Vice President FirstEnergy Nuclear Operating Company Beaver Valley Power Station Mail Stop A-BV-SEB1 P.O. Box 4, Route 168 Shippingport, PA 15077
SUBJECT:
BEAVER VALLEY POWER STATION, UNIT NOS. 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING END-OF-LiFE MODERATOR TEMPERATURE COEFFICIENT TESTING (TAC NOS. ME9144 AND ME9145)
Dear Mr. Harden:
By letter dated July 25, 2012 (Agencywide Documents Access and Management System Accession No. ML12208A309), First Energy Nuclear Operating Company (FENOC) submitted a proposed amendment to the Beaver Valley Power Station, Units 1 and 2, Technical Specifications (TSs). The proposed amendment would modify TS 3.1.3 to allow the normally required near-end-of-life Moderator Temperature Coefficient (MTC) measurement to not be performed under certain conditions. If these conditions are met, the MTC measurement would be replaced by a calculated value.
The Nuclear Regulatory Commission staff has been reviewing the submittal and has determined that additional information is needed to complete its review. The specific questions are found in the enclosed request for additional information (RAI). The questions were sent via electronic transmission on November 29, 2012, to Mr. Phil Lashley, of your staff. The draft questions were sent to ensure that the questions were understandable, the regulatory basis was clear, and to determine if the information was previously docketed. The questions were discussed with your staff on December 5, 2012, and it was agreed that a follow-up meeting will likely be necessary before a due date can be established. Further, FENOC and Westinghouse representatives confirmed that the questions were non-proprietary.
Please contact me at 301-415-2833, if you have any questions.
Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-334 and 50-412
Enclosure:
Request for Additional Information cc w/encl: Distribution via Listserv
REQUEST FOR ADDITIONAL INFORMATION REGARDING REQUEST TO REMOVE THE REQUIREMENT TO PERFORM NEAR-END-OF-CYClE MODERATOR TEMPERATURE COEFFICIENT MEASUREMENT BEAVER VAllEY POWER STATION, UNITS 1 AND 2 DOCKET NOS. 50-334 & 50-412 By letter dated July 25, 2012 (Agencywide Documents Access and Management System (ADAMS) Accession No. Ml12208A309), First Energy Nuclear Operating Company (FENOC, the licensee) submitted a license amendment request that would modify a surveillance requirement, in the plant technical specifications, to conditionally remove the requirement to perform the near-end-of-cycle measurement of the moderator temperature coefficient (MTC) at Beaver Valley Power Station, Units 1 and 2. Provided that the requisite conditions are satisfied, a value of the MTC predicted using the approach prescribed by the previously approved Topical Report WCAP-13749-P-A,1 "Safety Evaluation Supporting the Conditional Exemption 2 of the Most Negative [End-of-Life] EOl Moderator Temperature Coefficient Measurement," would be compared to the surveillance requirement limit, in lieu of a measured value. The U.S. Nuclear Regulatory Commission (NRC) staff has determined that the additional information requested below is needed to complete its review.
- 1. In accordance with the second condition in the NRC staff's safety evaluation for WCAP-13749-P-A, the licensee proposed to confirm, on a cycle-specific basis, that core fuel design changes or data from MTC predictions and measurements do not show a significant effect on the predictive correction. Please clarify the process and criteria for making this determination and justify their adequacy (e.g., statistical testing, engineering judgment, etc).
- 2. The predictive correction term defined in WCAP-13749-P-A is based, in part, on a tolerance limit that Westinghouse derived from differences between a set of measured and predicted values of the MTC at the beginning of an operating cycle at hot, zero power conditions. Specifically, the predicted MTC values in WCAP-13749-P-A were determined from calculations using the PHOENIX-P/ANC code package for a variety of pressurized-water reactor (PWR) core designs prior to 1995. Although the !\\IRC staff has approved the PARAGON lattice physics code as a replacement to PHOENIX-P, it cannot not be concluded that the statistical database, and hence the predictive correction terms, for the two codes will be equivalent. Therefore, if approval for the use
- 1.
A non-proprietary version of WCAP-13749-P-A, WCAP-14851-A, with the same title as WCAP-13749-P-A, is available at ADAMS Legacy Accession No. 9704230055. ADAMS Legacy documents are available through the NRC's Public Document Room.
- 2.
Note that WCAP-13749-P-A uses the term "conditional exemption." This is not to be confused with the U.S.
Nuclear Regulatory Commission's (NRC's) terminology for an "exemption" from the requirements of Title 10 of the Code of Federal Regulations (10 CFR). To maintain consistency with WCAP-13749-P-A, the term "conditional exemption" is used in this request for additional information (RAI), but the use of that terminology here does not imply that the licensee is requesting an exemption from a requirement in 10 CFR.
Enclosure
- 2 of the predictive correction term derived for the PHOENIX-P code for calculations with the PARAGON code is sought under this license amendment request, please provide unbiased and statistically significant data analogous to that reported in Table 3-1 of WCAP-13749-P-A for calculations performed with the PARAGON code for contemporary PWR core designs, along with: (1) justification that this data belongs to the same population as the pre-1995 data in WCAP-13749-P-A, generated with the PHOENIX-P code; or (2) a new predictive correction term for the PARAGON code for contemporary cores that is based on a 95/95 tolerance limit appropriate for modifying end-of-cycle MTC predictions made with this code.
- 3. The staff found the benchmark criteria for application of the conditional exemption methodology in Table 3-2 ofWCAP-13749-P-A to be acceptable for the PHOENIX-P code. However, due to the expectation that different codes will lead to different measured-min us-predicted deviation statistics for parameters such as the beginning-of cycle, hot zero-power isothermal temperature coefficient (BOC HZP ITC) and core reactivity difference, it is not clear that the criteria in Table 3-2 are adequate for the PARAGON code. In essence, the criteria of Table 3-2 should be capable of ensuring that a modified prediction of the MTC is substituted for a measured value only when a given core is observed to behave in a way that is represented by the data used to derive the predictive methodology. Similarity to past data serves as an inductive argument that a given core's characteristics are predictable. Therefore, it is critical that adequate criteria are established to discriminate when the conditional exemption may be permitted based on similarity to existing data for representative core designs. It is further clear that this determination may be code-dependent. Therefore, if approval for the use of the conditional exemption criteria in Table 3-2 of WCAP-137 49-P-A with the PARAGON code is sought under this license amendment request, please provide justification that these criteria are appropriate based on unbiased and statistically significant data for BOC HZP ITC and core reactivity difference calculations performed with the PARAGON code for contemporary PWR core designs; alternately, please propose new criteria that are acceptable for predictions using the PARAGON code.
December 28,2012 Mr. Paul A. Harden Site Vice President FirstEnergy Nuclear Operating Company Beaver Valley Power Station Mail Stop A-BV-SEB1 P.O. Box 4, Route 168 Shippingport, PA 15077
SUBJECT:
BEAVER VALLEY POWER STATION, UNIT NOS. 1 AND 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING END-OF-LiFE MODERATOR TEMPERATURE COEFFICIENT TESTING (TAC NOS. ME9144 AND ME9145)
Dear Mr. Harden:
By letter dated July 25,2012 (Agencywide Documents Access and Management System Accession No. ML12208A309), First Energy Nuclear Operating Company (FENOC) submitted a proposed amendment to the Beaver Valley Power Station, Units 1 and 2, Technical Specifications (TSs). The proposed amendment would modify TS 3.1.3 to allow the normally required near-end-of-life Moderator Temperature Coefficient (MTC) measurement to not be performed under certain conditions. If these conditions are met, the MTC measurement would be replaced by a calculated value.
The Nuclear Regulatory Commission staff has been reviewing the submittal and has determined that additional information is needed to complete its review. The specific questions are found in the enclosed request for additional information (RAI). The questions were sent via electronic transmission on November 29, 2012, to Mr. Phil Lashley, of your staff. The draft questions were sent to ensure that the questions were understandable, the regulatory basis was clear, and to determine if the information was previously docketed. The questions were discussed with your staff on December 5,2012, and it was agreed that a follow-up meeting will likely be necessary before a due date can be established. Further, FENOC and Westinghouse representatives confirmed that the questions were non-proprietary.
Please contact me at 301-415-2833, if you have any questions.
Sincerely, IRA!
Peter Bamford, Project Manager Plant Licensing Branch 1-2 Division of Operating Reactor licenSing Office of Nuclear Reactor Regulation Docket Nos. 50-334 and 50-412
Enclosure:
Request for Additional Information cc w/encl: Distribution via Listserv DISTRIBUTION:
PUBLIC RidsOgcRp Resource LPLI-2 RtF RidsAcrsAcnw_MailCTR Resource RidsNrrDssSnpb Resource SMiranda, NRR RidsRgn1 MailCenter Resource RidsNrrDorlDpr Resource RidsNrrDorlLpl1-2 Resource RidsNrrPMBeaverValley Resource RidsNrrLAABalder Resource JLehning. NRR ADAMS Accession Number: ML12340A256
- via memo OFFICE LPLI-2/PM LPLI-2/LA SNPBIBC LPLI-2/BC NAME PBamford ABaxter AMendiola*
JHughey for MKhanna DATE 12/12/12 12/12/12 11/27/2012 12/28/12 OFFICIAL RECORD COPY