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| Quarter | Site | Title | Description | |
|---|---|---|---|---|
| 05000443/FIN-2016008-01 | 2016Q1 | Seabrook | Failure to Complete Operability Determinations for ASR-affected Structures | 10 CFR 50, Appendix B, Criterion V, Instructions, Procedures, and Drawings, states, in part, that activities affecting quality shall be prescribed by documented instructions, procedures or drawings, of a type appropriate to the circumstances, and shall be accomplished in accordance with these instructions, procedures or drawings. NextEra Nuclear Fleet Administrative Procedure, EN-AA-203-1001, Operability Determinations/Functionality Assessments, identifies the responsibilities and requirements for preparation and approval of Immediate Operability Determinations (IOD) and Prompt Operability Determinations (POD) for establishing the acceptability of continued operation of a plant structure, system, or component that is suspected to be degraded or nonconforming. Per Section 2.0, Terms and Definitions, IODs are performed by the Shift Manager without delay (within 8 hours of discovery), using best available information to make an operability declaration. Upon request of the Shift Manager, a POD is performed as a follow-up to an IOD when additional information is needed to confirm the declaration of operability. Contrary to the above, on two occasions between March 17, 2015, and January 22, 2016, Energy Seabrook, LLC (NextEra) did not accomplish an activity affecting quality in accordance with its procedure. Specifically, NextEra received information from vendors identifying non-conforming conditions adversely impacting two reinforced concrete structures at Seabrook Station, and did not complete an appropriate IOD or initiate a follow-up POD to evaluate the impact of that non-conforming condition on structural performance. In particular, 1) On March 17, 2015, NextEra entered a WJE report, entitled Condition Assessment of the Cracking in the RHR and CS Equipment Vault, into the station document tracking system and added the reports recommendations into the Corrective Action Program under Action Report (AR) 01977456, without completing an appropriate IOD or initiating a POD. The report identified structural loading (a load not considered by ACI 318-71, the design and construction code of record) due to ASR as the cause for the excessive bulk expansion and cracking of the RHR/CS Vault interior and exterior support walls; and 2) On December 2, 2015, NextEra initiated AR 02094762 to track recommendations from SG&H report entitled Evaluation and Design Confirmation of As-Deformed CEB, without completing an appropriate IOD or initiating a POD. The report also identified structural loading due to ASR as the cause for deformation of the Containment Enclosure Building (CEB), a condition not conforming with ACI 318-71. This violation is associated with a Green Significance Determination Process finding. |
| 05000443/FIN-2015004-01 | 2015Q4 | Seabrook | Issue of Concern Regarding Implementation of the Seabrook Structures Monitoring Program and structural evaluations of the CEB and RHR/CS Vault | During the week of October 26, 2015, the NRC audit team observed the last planned large-scale specimen testing at FSEL, reviewed test program results and analyses completed, to date, and interviewed NextEra staff and their consultants. Audit team activities and conclusions are documented in an NRC audit report (ADAMS Accession No. ML15307A019) dated December 17, 2015. No significant observations or concerns were identified related to the conduct of testing to appropriate quality assurance criteria. NextEra staff planned to have the test data analyses completed by the end of 2015, in support of submitting to the NRC a license amendment request in 2016, to address an ASR-related non-conforming condition with the current licensing basis. NRC inspectors conducted in-office reviews of the root cause evaluation for the Containment Enclosure Building Local Deformation, Event Dated December 19, 2014, completed per AR 02014325, and the Condition Assessment of Cracking in RHR and CS Equipment Vault, documented in Foreign Print (FP) 100903, dated March 17, 2015. NextEras CEB RCE described two root causes. First, regarding the physical causes of CEB deformation, NextEra staff concluded that internal expansion (strain) produced by ASR in the CEB concrete (in-plane direction of the CEB shell) and ASR expansion in the backfill concrete, coincident with a unique building configuration, resulted in CEB deformation. Second, regarding NRC identification of this issue, NextEra concluded this was not identified by plant staff due to an organizational mindset that viewed conditions such as concrete cracks, water infiltration, and misalignment issues as acceptable and inconsequential. Additionally, the RCE identified that NextEra staff did not perform and document comprehensive evaluations of building conditions that could have potentially revealed more significant underlying conditions, such as localized deformation of the CEB. These NRC-identified performance deficiencies were previously dispositioned as non-cited violation (NCV) 2015002-01 and NCV 2015002-02 in NRC inspection report 05000443/2015002 (ADAMS Accession No. ML15217A256). The inspectors determined NextEra corrective actions to address these problems included: 1) a revision to their design control procedures to require pozzolanic materials like fly ash or slag cement to be added to concrete mixes to prevent ASR in any new concrete structures; and, 2) the implementation of multiple training and program changes to correct the organizational mindset issues and strengthen individual responsibilities and accountability for implementation of the Seabrook Structures Monitoring Program. The inspectors concluded the RCE was reasonably thorough and utilized a cause and effect methodology that was appropriate to the problem statement. However, NextEras RCE, dated December 19, 2014, concluded that the reason that NRC inspectors, and not plant staff, identified the presence of localized ASR-induced deformation in Seabrooks concrete structures was due to an organizational mindset that viewed conditions such as concrete cracks, water infiltration, and misalignment issues as acceptable and inconsequential. The inspectors concluded the RCE was reasonably thorough and utilized a cause and effect methodology that was appropriate to the problem statement. The planned and in-process organizational and program related corrective actions appeared appropriately focused on the identified causes of the problem. However, the inspectors concluded that the corrective actions, taken to date, to implement multiple training, program and oversight changes to correct the organizational mindset issues and strengthen individual responsibilities and accountability for implementation of the Seabrook Structures Monitoring Program have either not been implemented or are not yet effective and thus require additional management attention near-term. The inspectors noted that the CEB RCE referenced the results of a Finite Element Analysis (FEA) model of the CEB. The FEA and results were documented in FP 100985. The inspectors review of FP 100985 identified that the FEA model simulated ASR expansion to assess the impact of expansion induced deformation on the structural performance of the CEB. The FEA evaluated CEB design capacity against assumed loading, based on ACI 318-71 criteria, including simulated loads associated with the as-deformed condition. As documented in FP 100985, the FEA model also simulated the impact of the external structural loading due to ASR expansion of the backfill concrete. Based upon the review of the CEB structural assessment described in FP 100985 and the limited structural analysis of the RHR/CS vault documented in FP100903, the inspectors had multiple follow-up questions regarding the CEB and RHR/CS vault structural assessments and the potential impact of these evaluation results on NextEras open Immediate Operability Determinations and Prompt Operability Determinations (PODs) for these ASR-affected structures (reference AR 01664399, AR 01929460, AR 01977456, AR 02004749, and AR 02044627). The follow-up questions were developed via a collegial review by the Region 1 Senior Reactor Analyst and structural engineers from NRC Offices of Nuclear Reactor Regulation and Region 2, under the auspices of the Seabrook ASR Technical Team (ADAMS Accession No. ML14014A378). The questions were documented and shared with the NextEra staff on December 23, 2015 (ADAMS Accession No. ML15357A326). NextEras responses and the inspectors review are planned for the first quarter of 2016 and will be documented in an NRC inspection report. Following the guidance of IMC 0612, Power Reactor Inspection Reports, the inspectors identified an issue of concern regarding NextEras implementation of their Seabrook Structures Monitoring Program. Specifically, the structural evaluations, performed by contractors and accepted by NextEra staff via the FP process, included discussions that identified the potential to exceed limits in the applicable design code (ACI 318-71) for specific locations in the CEB and RHR/CS vault walls. The evaluations further recommended actions to determine whether this was the case. The inspectors noted that the Seabrook staff screened or reviewed these evaluations without documenting a justification in a revision or update to the open PODs for these structures. The additional information requested on December 23, 2015 is required for the inspectors to determine whether this issue involves a performance deficiency. As a result, the NRC opened an unresolved item (URI). The inspectors identified an issue of concern regarding NextEras implementation of the Seabrook structures monitoring program and acceptance of evaluations via the FP and CAP. Additional inspection is warranted to determine whether a performance deficiency exists related to NextEras disposition of FP 100985 for the CEB condition and FP 100903 for the RHR/CS vault condition. Specifically, further inspection is warranted to determine whether NextEra staff properly implemented the Seabrook structures monitoring program for the acceptance and review of structural evaluations potentially impacting the functionality of the CEB and RHR/CS vault, as currently documented in open PODs. |