ML102670740

Draft RAIs (Emcb) HELB Associated EPU License Amendment Request

ML102670740
Person / Time
Site:	Point Beach
Issue date:	09/10/2010
From:	Beltz T Plant Licensing Branch III
To:	Hale S Point Beach
beltz T, NRR/DORL/LPL3-1, 301-415-3049
Shared Package
ML102670745	List: ML102670737 ML102670740
References
TAC ME1044, TAC ME1045
Download: ML102670740 (4)

Text

REQUESTS FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST (LAR-261)

POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 RENEWED FACILITY OPERATING LICENSE NOS. DPR-24 AND DPR-27 DOCKET NOS. 50-266 AND 50-301 By letter to the Nuclear Regulatory Commission (NRC), dated April 7, 2009, NextEra Energy Point Beach, LLC (NextEra or the licensee) submitted a license amendment request (LAR) for the Point Beach Nuclear Plant, Units 1 and 2. The proposed license amendment would increase each units licensed thermal power level from 1540 megawatts thermal (MWt) to 1800 MWt, and revise the technical specifications to support operations at the increased thermal power level.

By letter dated July 8, 2010, the licensee submitted a response to the NRC staffs request for additional information (Reference 1) with regards to the high energy line break (HELB) portion of the extended power uprate (EPU) LAR. Enclosure 1 of Reference 1 contained 18 attachments.

The staff in the Mechanical & Civil Engineering Branch performed a review of Attachments 1 - 9, 11, 12 and 16 of Enclosure 1 of Reference 1. Based on its review, the NRC staff has determined that the following additional information is required to continue its review of the licensees HELB portion of the EPU LAR.

EMCB (HELB) RAI 1 The licensees calculations entitled PBNP-994-21-05-P05, Revision 0, Steam Supply Piping to AFW Pump/GL 87-11 Break Location Determination, and PBNP-994-21-05-P06, Revision 0, Steam Supply Piping to AFW Pump/GL 87-11 Break Location Determination, (Enclosure 1, Attachments 7 and 8, to Reference 1), establish the respective locations of intermediate high energy large breaks and leakage cracks for the 3-in steam supply piping from the main steam headers to the auxiliary feedwater (AFW) pumps 1P-29 and 2P-29, at Point Beach Units 1 and

2. However, the pipe stress analysis reports listed in Reference 6 of Attachments 7 and 8 of Reference 1 do not address EPU, and may not include increases in piping temperatures or changes to the piping configurations for these piping subsystems due to EPU.

Please provide additional detail to document that the Reference 6 calculations in Attachments 7 and 8 of Reference 1 remain valid for the EPU conditions.

EMCB (HELB) RAI 2 The licensees letter dated April 7, 2009 (Reference 2), Section 3.2.2, High Energy Line Break, notes in part that: For those high energy systems that did not have the benefit of having a dynamic seismic analysis, a break was postulated at the weld to every fitting, valve and welded attachment. Rather than determining all of these locations, a break was postulated in every compartment the piping run traversed. In addition, a crack was postulated to occur anywhere along the run of the pipe at the most adverse location. The Automated Engineering Services Corporation paper entitled: Technical Position Paper for Establishing HELB Break & Leakage Crack Location Selection Criteria, Revision 1, dated August 7, 2008, is documented in several of the attachments in Enclosure 1 to Reference 1. Subsection 3.3 of Section 3.0 of the position paper, Proposed Unified PBOC Criteria for the PBNP HELB Reconstitution Program, proposes, in part, to: Adopt the use of GL 87-11 and MEB 3-1, Rev, 2 rules for HE lines only, including the rules for break and leakage crack locations in their entirety. Subsection 3.7 of Section 3.0 of the position paper notes that: Where break locations are selected without the benefit of stress calculations, it is recommended that breaks be postulated at the piping welds to each fitting, valve, or welded attachment. This recommendation is consistent with the recommendation of Section B.1.c(2)(b)(i) of Branch Technical Position MEB 3-1, Postulated Rupture Locations in Fluid System Piping Inside and Outside Containment, Revision 2, dated June 1987.

Please provide additional detail to justify implementing its HELB LAR for unanalyzed piping, without implementing Section B.1.c(2)(b)(i) of Branch Technical Position MEB 3-1.

EMCB (HELB) RAI 3 The licensees calculation entitled PBNP-994-21-12, Revision 0, Task 12 Jet Impingement Calculations - Attachment 2 Break Sizes and Operating Parameters, (Enclosure 1, Attachment 12, to Reference 1), prepares new jet impingement centerline pressure and temperature versus distance calculations for the Point Beach Nuclear Plant, Units 1 and 2. Based on the NRC staffs review of the calculation, the staff requests that the licensee provide the following additional details for the calculation:

(a) Provide additional details for the operable but non-conforming condition documented in Section 1, Purpose, of the calculation, including a discussion to document that the calculation resolves the operable but non-conforming condition.

(b) Provide additional details to document the discovery date of the operable but non-conforming condition.

(c) The staff recommends that the licensee revise Assumption F of Section 1, Purpose, to change: Jet expansion with a zone of five pipe diameters to: Jet expansion within a zone of five pipe diameters.

EMCB (HELB) RAI 4

, Break and Crack Sizes and Operating Parameters, (Enclosure 1, Attachment 12, to Reference 1), documents in part that: The operating parameters for main steam and steam generator blowdown are determined at hot shutdown, which are the same at the current power level and EPU power level.

Please provide additional detail and justification to document that the main steam flow rate remains unchanged from current power levels or increases for EPU.

EMCB (HELB) RAI 5 Section 1, Purpose, of the calculation entitled PBNP-994-21-12, Revision 0, Task 12 Jet Impingement Calculations - Attachment 2 Break Sizes and Operating Parameters, (Enclosure 1, Attachment 12, to Reference 1), documents, in part, that the calculation supersedes the extensive discussion of jet impingement methodology provided in FSAR Appendix A.2, Addendum 1 to reflect changes in methodologies used to determine HELB parameters (a) The licensee is requested to provide a summary table documenting the differences in methodologies between the current licensing basis (CLB) and the proposed EPU.

(b) The licensee is also requested to document if any plant modifications such as pipe support modifications, or additional whip restraints, or jet shields, are required as a result of the licensees HELB reconstitution and methodology changes.

(c) Section 8, Calculation, documents that: The methodology of Section 2 was applied to the break sizes and operating parameters in Attachment 2 with the assumptions in Section 3. However, the methodology is described in Section 3, not Section 2, and the assumptions are listed in Section 4 and not Section 3. The licensee is requested to clarify these discrepancies.

EMCB (HELB) RAI 6

, Break and Crack Sizes and Operating Parameters, (Enclosure 1, Attachment 12, to Reference 1), documents that the CLB (FSAR Appendix A.2) did not address high energy systems such as CVCS letdown or other systems in the Turbine Hall. The calculation addresses the CVCS letdown system.

Please describe if any plant modifications such as pipe support modifications, or additional whip restraints, or jet shields, are required as a result of the licensees HELB reconstitution and methodology changes and the inclusion of the CVCS letdown system.

EMCB (HELB) RAI 7 Please provide a summary list of changes, additions as well as deletions, of pipe breaks and locations, whip restraints, jet shields, jet impingement targets, consequences and mitigation of the effects of HELB, and to identify the corresponding piping systems as a result of the HELB reconstitution.

Please clarify if the above changes are due to HELB reconstitution or EPU.

EMCB (HELB) RAI 8 Please provide any changes in analytical methodology, such as, coupling or decoupling of branch lines from the main line analysis for any high energy piping systems. The licensee is requested to identify any decoupled high energy lines that were coupled with the main runs in the previous stress analyses. In considering these questions, it should be noted that a branch connection to a main piping run is a terminal end of the branch run, except where the branch run is classified as part of a main run in the stress analysis.

EMCB (HELB) RAI 9 Since the HELB methodology is changing from the CLB in the PBNP FSAR Appendix A.2, the licensee is requested to provide a summary of the FSAR revision for the revised licensing basis.

References

1.

NextEra Energy Letter dated July 8, 2010, entitled Point Beach Nuclear Plant, Units 1 and 2 / Dockets 50-266 and 50-301 / Renewed License Nos. DPR-24 and DPR-27, License Amendment Request 261 / Extended Power Uprate / Response to Request for Additional Information, (ADAMS Accession No. ML1019403630)

2.

FPL Energy Point Beach Nuclear Plant letter dated April 7, 2009, entitled Point Beach Nuclear Plant, Units 1 and 2 / Dockets 50-266 and 50-301 / Renewed License Nos.

DPR-24 and DPR-27, License Amendment Request 261 / Extended Power Uprate, (ADAMS Accession No. ML091250564)