ML16224A795

Edwin I. Hatch Nuclear Plant - NRC Inspection Report 05000321/2016010, February 22, 2016, June 30, 2016

ML16224A795
Person / Time
Site:	Hatch
Issue date:	08/11/2016
From:	Gody A T Division of Reactor Safety II
To:	Vineyard D R Southern Nuclear Operating Co
References
EA-16-136 IR 2016010
Download: ML16224A795 (13)

See also: IR 05000321/2016010

Text

August 11, 2016

EA-16-136

Mr. David Vineyard Vice President Southern Nuclear Operating Company, Inc. Edwin I. Hatch Nuclear Plant 11028 Hatch Parkway North Baxley, GA 31513

SUBJECT: EDWIN I. HATCH NUCLEAR PLANT - NRC INSPECTION REPORT 05000321/2016010

Dear Mr. Vineyard:

This refers to an inspection completed on June 30, 2016 by the Nuclear Regulatory Commission concerning activities at Southern Nuclear Company's (SNC) Edwin I. Hatch Nuclear Plant Unit 1. The purpose of the inspection was to review the circumstances involving the February 2016 identification of an axial linear flaw in a weld located on a non-isolable portion of the Unit 1 recirculation system feedwater piping. In this case, the weld flaw was originally identified by SNC in October of 1988, and repaired using welding techniques acceptable at that time. During the February 2016 refueling outage, as part of the activities associated with installation of a full- structural weld overlay (FSWOL), your staff discovered that the weld flaw had grown through the entire thickness of the original weld and into the overlay material installed in 1988. SNC's review ultimately determined that this condition had existed since at least 2006. On two occasions, SNC submitted requests to relax the frequency of required non-destructive examinations of this weld. Specifically, the basis of the requests stated that the weld had been modified with a standard weld (i.e., FSWOL), when in fact it had only been modified with a less robust design overlay (leak barrier). On the basis on these inaccurate statements, the NRC approved the licensee's requests/proposed alternatives. Had SNC's submittals correctly identified the nature of the original weld repair, it is unlikely that the NRC would have approved the reliefs/proposed alternatives without requiring the use of a more robust weld repair technique. The NRC notes that the axial weld flaw did not result in any RCS pressure boundary leakage during operation of Unit 1, nor did it result in a significant loss of structural integrity. Additionally, SNC has repaired the weld using a FSWOL, and initiated corrective actions as discussed in the enclosed inspection report.

Based on the results of this inspection, one NRC-identified Green non-cited violation, and one apparent violation (AV) involving 10 CFR 50.9, "Completeness and Accuracy of Information," were identified. The AV is being considered for escalated enforcement action in accordance with the NRC's Enforcement Policy. The current Enforcement Policy is included on the NRC's Web site at http://www.nrc.gov/about-nrc/regulatory/enforcement/enforce-pol.html. The AV involves two examples in which SNC failed to provide information to the NRC that was complete and accurate in all material respects. Specifically, the first example occurred on October 17, 1995, as part of the 3rd 10-Year Interval Inservice Inspection Program submittal, SNC requested relief from American Society of Mechanical Engineers (ASME) Code requirements (as clarified in NUREG-0313 Rev. 2 and GL 88-01). The basis for this request was that weld overlay 1B31-1RC-12BR-E-5 was of standard overlay design (e.g., FSWOL),

when in fact, the overlay was a "design" overlay (leak barrier). The second example occurred on May 30, 2000 when SNC submitted a letter, "Edwin I. Hatch Nuclear Plant - Unit 1, Reactor Coolant System (RCS) Weld Overlay Examinations." In this letter, SNC requested to defer the required ultrasonic testing exam for the 1B31-1RC-12BR-E-5 weld overlay, again based in part that it was an FSWOL when in fact, the overlay was a less robust design overlay.

These submittals were material to the NRC because they were used by the NRC to approve the reliefs/proposed alternatives. The basis for the NRC's approval was the statement by the licensee that an FSWOL had been installed. Had SNC's submittals correctly identified the weld overlay as a design overlay, it is unlikely that the NRC would have approved the reliefs/proposed alternatives.

The circumstances surrounding this AV, your corrective actions, the significance of the issue, and the need for lasting and effective corrective action were previously discussed between members of your staff and the NRC. As a result, it may not be necessary to conduct a pre-

decisional enforcement conference in order to enable the NRC to make an enforcement decision. In addition, because your facility has not been the subject of escalated enforcement within the past two years, and based on our current understanding of your corrective actions, a civil penalty may not be warranted in accordance with Section 2.3.4 of the Enforcement Policy. The final decision will be based on you confirming on the license docket that the corrective actions previously described or discussed with the NRC staff have been or are being taken.

Before the NRC makes its enforcement decision, we are providing you an opportunity to (1) respond in writing to the AV in this inspection report within 30 days of the date of this letter, or (2) request a Pre-decisional Enforcement Conference (PEC). If a PEC is held, the NRC will issue a press release to announce the time and date of the conference, and the conference will be open to public observation. If you decide to participate in a PEC, please contact Shakur Walker at 404-997-4639 within 10 days of the date of this letter. A PEC should be held within 30 days of the date of this letter.

If you choose to provide a written response, it should be clearly marked as a "Response to Apparent Violations in NRC Inspection Report 05000321/2016010, EA-16-136" and should include (1) the reason for the AVs or, if contested, the basis for disputing the apparent violation; (2) the corrective steps that have been taken and the results achieved; (3) the corrective steps that will be taken; and (4) the date when full compliance will be achieved. Your response may reference or include previously docketed correspondence, if the correspondence adequately addresses the required response. Additionally, your response should be sent to the NRC's Document Control Center, with a copy mailed to Anthony Gody, Director of Reactor Safety, Region II, 245 Peachtree Center Avenue NE, Atlanta, GA 30303, within 30 days of the date of this letter. If an adequate response is not received within the time specified or an extension of time has not been granted by the NRC, the NRC will proceed with its enforcement decision or schedule a PEC. If you choose to request a PEC, the conference will afford you the opportunity to provide your perspective on these matters and any other information that you believe the NRC should take into consideration before making an enforcement decision. The decision to hold a PEC does not mean that the NRC has determined that a violation has occurred or that enforcement action will be taken. This conference would be conducted to obtain information to assist the NRC in making an enforcement decision. The topics discussed during the conference may include information to determine whether a violation occurred, information to determine the significance of a violation, information related to the identification of a violation, and information related to any corrective actions taken or planned. In addition, please be advised that the number and characterization of apparent violation described in the enclosed inspection report may change as a result of further NRC review. You will be advised by separate correspondence of the results of our deliberations on this matter.

In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice and Procedure," a copy of this letter, its enclosures, and your response, if you choose to provide one, will be made available electronically for public inspection in the NRC Public Document Room or from the NRC's Agencywide Documents Access and Management System (ADAMS), accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html. To the extent possible, your response should not include any personal privacy, proprietary, or safeguards information so that it can be made available to the Public without redaction.

For administrative purposes, this letter is issued as Inspection Report 05000321/2016010 and the apparent violation is designated as AV 05000321/2016010-01, Failure to Provide Complete and Accurate Information.

If you have any questions concerning this matter, please contact Mr. Shakur Walker of my staff at 404-997-4639.

Sincerely,/RA/ Anthony T. Gody, Director Division of Reactor Safety Docket No. 50-321 License No. DPR-57

Enclosure:

Edwin I. Hatch Nuclear Plant - NRC Inspection Report 05000321/2016010

w/Attachment:

Supplementary Information

SUMMARY

IR 05000321/2016010; February 22, 2016 through June 30, 2016; Edwin I. Hatch Nuclear Plant, Unit 1; In-Service Inspection Report.

This report covered a follow-up inspection of unresolved item 05000321/2016001-01 by one regional inspector. One NRC-identified non-cited violation (NCV); and one apparent violation (AV) which is being considered for escalated enforcement action in accordance with the NRC Enforcement Policy, are documented in this report. The significance of inspection findings are indicated by their color (i.e., greater than Green, or Green, White, Yellow, Red) and determined using Inspection Manual Chapter (IMC) 0609, "Significance Determination Process" (SDP)dated June 19, 2012. The cross-cutting aspects are determined using IMC 0310, "Aspects within the Cross-Cutting Areas," dated December 4, 2014. All violations of NRC requirements are dispositioned in accordance with the NRC's Enforcement Policy dated August 1, 2016. The NRC's program for overseeing the safe operations of commercial nuclear power reactors is described in NUREG-1649, "Reactor Oversight Process," Rev. 5.

Cornerstone: Initiating Events

• AV: The NRC identified an AV of 10 CFR 50.9, "Completeness and Accuracy of Information," for the licensee's failure to provide data to the NRC that was accurate in all material aspects. Specifically, on two occasions (October 1995, May 2000), the licensee stated that weld 1B31-1RC-12BR-E-5 had been modified with a full-structural weld overlay (FSWOL), when in fact it had only been modified with a less robust design overlay (leak barrier). The NRC approved the licensee's requests/proposed alternatives in part based on the inaccurate characterization of the welds. The licensee has since installed the FSWOL and entered the issue into the corrective action program as CR 10197850. The NRC is considering escalated enforcement on the basis that had the licensee provided accurate information, it would likely have caused the NRC to reconsider a regulatory position. (Section 1R08)

• Green: The inspectors identified a Green NCV of 10 CFR 50, Appendix B, Criterion XVI, "Corrective Actions," for the licensee's failure to promptly identify a condition adverse to quality regarding a through-wall flaw in the safe end-to-nozzle weld of the reactor coolant system N2E nozzle. The licensee has since repaired the flaw, completed all required post-repair examinations, and entered this issue entered this into their corrective action program as CR 10247856. The performance deficiency was more than minor because it was associated with the Equipment Performance attribute of the Initiating Events cornerstone and adversely affected the cornerstone objective of limiting the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. The inspectors screened this finding using IMC 0609, Appendix A, "The Significance Determination Process (SDP) For Findings At-Power", dated June 19, 2012. Because after a reasonable assessment of degradation, the finding could neither result in exceeding the RCS leak rate for a small LOCA, nor likely affected other systems used to mitigate a LOCA resulting in a total loss of their function, the finding screened as

Green.

This finding has a cross-cutting aspect of Challenge the Unknown in the area of Human Performance (H.11)

because upon discovery of a less robust configuration of the N2E nozzle overlay, the licensee failed to consider the implications on the flaw that had existed in that component since 1988. (Section 1R08)

REPORT DETAILS

REACTOR SAFETY

Cornerstones: Initiating Events, Barrier Integrity, and Mitigating Systems

1R08 Inservice Inspection Activities

.1 URI 05000321/2016001-01, Reactor Coolant System N2E Weld Flaw

a. Inspection Scope

In Inspection Report 05000321/2016001, the inspectors identified an unresolved item (URI) associated with a flaw in the 1B31-1RC-12BR-E-5 ("N2E") safe end-to-nozzle weld of the reactor coolant system (RCS). In July 2015, the licensee submitted a proposed alternative to the American Society of Mechanical Engineers (ASME) Code, HNP-ISI-ALT-15-01 (ADAMS Accession Number ML15183A354), to install a full-structural weld overlay (FSWOL) on the N2E nozzle. This proposed alternative was approved by the NRC in December 2015 (ADAMS Accession Number ML15349A973). The licensee implemented this proposed alternative during the February 2016 refueling outage (1R27). After removing all but 1/16" of the existing overlay, the licensee performed a liquid penetrant examination and noted a pair of linear indications. Subsequently, the licensee determined that these indications were actually a single indication, and that it exceeded allowable size limitations according to ASME Code. Upon further review, the licensee realized that these indications were potentially the result of growth of an inner-diameter, surface-connected intergranular stress corrosion cracking (IGSCC) flaw found in 1988. On April 14, 2016, the licensee submitted Licensee Event Report (LER) 05000321/2016-003, "Reactor Coolant System Piping Has Unacceptable Weld Indication Discovered During Refueling Outage," as a result of the discovery, due to a principal safety barrier being seriously degraded. The licensee has repaired the flaw, installed the full-structural weld overlay, and completed all required post-installation examinations. The URI was opened to allow the inspectors to determine whether the licensee performed all required examinations of the N2E nozzle between 1988 and 2016, and whether the flaw exceeded minimum wall limitations at some point during prior operation. The inspectors identified one apparent violation (AV) with two examples, and one non-associated Green NCV. Both are described below in 1R08.b. Accordingly, URI 05000321/2016001-01 and LER 05000321/2016-003 have been closed.

b. Findings

(i) Inaccurate Information Provided Regarding N2E Nozzle Weld Overlay

Introduction:

The NRC identified an AV of 10 CFR 50.9, "Completeness and Accuracy of Information," for the licensee's failure to provide data to the NRC that was accurate in all material aspects. Specifically, on two occasions (October 1995, May 2000), the licensee stated that the N2E nozzle weld had been modified with a FSWOL, when in fact it had only been modified with a less robust design overlay (leak barrier). The NRC has not made an enforcement decision for this AV.

Description:

In October 1988, during refueling outage 1R11, the licensee performed an ultrasonic examination (UT) on the N2E nozzle weld and identified an indication in the weld. The licensee evaluated the indication and determined that it was unacceptable by ASME Section XI criteria. In November 1988 (still 1R11 outage), the licensee installed a "design" weld overlay (leak barrier) consistent with paragraph 4.4.2 of NUREG-0313 Revision 2, "Technical Report on Material Selection and Processing Guidelines for BWR Coolant Pressure Boundary Piping," (ADAMS Accession Number ML031470422). At the time, the acceptable inspection methodology was delineated in GL 88-01, "NRC Position on IGSCC in BWR Austenitic Stainless Steel Piping," (ADAMS Accession Number ML031430193). The licensee appropriately classified the N2E weld as a Category E weld according to this guidance, and as such, the weld was to be inspected the following refueling outage and then every other refueling outage thereafter. The licensee completed the required examinations in 1R12 (March 1990), 1R13 (October 1991) and 1R15 (October 1994) and noted no appreciable change in flaw geometry through these three exams. On October 17, 1995, the licensee submitted their 3rd 10-year Interval Inservice Inspection (ISI) Program to the NRC. In that letter, the licensee detailed their plan to revise the frequency of the N2E examinations from every-other-outage to once-per-10-years, and stated that one of the bases for this decision was that the overlay was a "standard" overlay. This information was not accurate, in that the overlay was, in fact, a less robust "design" overlay. In September 1997, on the basis of the information submitted, the NRC approved the licensee's proposed plan. On June 17, 1999, the NRC sent a letter to the Boiling Water Reactor Vessel and Internals Program (BWRVIP) Chairman which stated that several plants, including Hatch Unit 1, were scheduled for fall 1999 outages, and that deferral of the required exams would be acceptable provided certain criteria were met. One of the criteria was that "The overlay for which deferral is applied meets GL 88-01 or ASME Code Case N-504 (full structural overlay) as opposed to a temporary duty (leakage barrier) overlay." On May 30, 2000, the licensee submitted a letter to the NRC requesting deferral of the N2E exam on the basis of the NRC's June 1999 letter. In this letter, the licensee stated that "[The N2E weld overlay was] designed and applied as full structural weld overlay." This information was not accurate, in that the overlay was, in fact, a "design" overlay. In October 2000, on the basis of the information submitted, the NRC approved this approach for one refueling cycle (1R19 to 1R20).

Analysis:

The licensee's failure to provide information required by the Commission's regulations, orders and license conditions that was complete and accurate in all material aspects was a violation of NRC requirements. The NRC determined that this violation was not associated with a common performance deficiency.

The ROP's significance determination process does not specifically consider the regulatory process impact in its assessment of licensee performance. Because the regulatory process was affected, it is necessary to address this violation which impeded the NRC's ability to regulate using traditional enforcement. Using the examples provided in Section 6.9.c.1 of the NRC Enforcement Policy, the NRC is considering escalated enforcement on the basis that had the licensee provided accurate information, it would likely have caused the NRC to reconsider a regulatory position. Specifically, the licensee submitted information to the NRC stating that the N2E nozzle weld overlay was a "standard" overlay, when in fact, it was a less robust "design" overlay. Traditional enforcement violations are not assessed for cross-cutting aspects.

Enforcement:

Title 10 CFR 50.9, "Completeness and Accuracy of Information," states, in part, that information required by the Commission's regulations, orders, and license conditions shall be complete and accurate in all material aspects. Contrary to the above, on two occasions (October 17, 1995 and May 30, 2000), the licensee failed to provide information that was complete and accurate in all material aspects. Specifically, the licensee stated that the N2E nozzle weld overlay was a "standard" overlay, when in fact, it was a less robust "design" overlay. These submittals were material to the NRC in that they were instrumental in the NRC's approval of the licensee's requests for relief/proposed alternative. Had the correct information been provided, it would have likely caused the NRC to reconsider its regulatory position. Compliance was restored in March 2016 when the licensee installed the "standard" (FSWOL) overlay. No enforcement is being issued at this time because the NRC has not made a final enforcement decision. The licensee entered this issue into their corrective action program (CAP) as CR 10197850. This violation is being treated as an AV pending a final enforcement determination. (AV 05000321/2016010-01, "Inaccurate Information Provided Regarding N2E Nozzle Weld Overlay") (ii) Failure to Identify N2E Nozzle Weld Through-Wall Flaw

Introduction:

The inspectors identified a Green NCV of 10 CFR 50 Appendix B Criterion XVI, "Corrective Actions," for the licensee's failure to promptly identify a condition adverse to quality regarding a through-wall flaw in safe end-to-nozzle weld of the RCS N2E nozzle.

Description:

On April 21, 2015, the licensee was preparing for the upcoming refueling outage and noted that the N2E weld overlay configuration did not match others of similar original construction. Specifically, the N2E weld was thought to be a "standard" overlay (FSWOL); however, was discovered to be a less robust "design" overlay (leak barrier). The licensee entered the issue into the CAP as CR 10058892 and decided that in order to obtain full coverage for the non-destructive examination in accordance with ASME Section XI requirements (for the 4th 10-year ISI interval), they needed to install a FSWOL. The licensee planned this activity for the upcoming 1R27 outage (February 2016). On July 2, 2015, the licensee submitted a letter to the NRC (ML15224B464)requesting approval for the proposed alternative (FWSOL), and on December 18, 2015, the NRC issued the approval SER (ML15349A973).

In February 2016, when installing the new FSWOL, the licensee identified two small, axial, linear indications - each of which was unacceptable by ASME criteria. In the follow-on corrective actions, the licensee determined that: (1) these two flaws were actually one flaw, (2) it was the same flaw that had been previously identified in October 1988, and (3) it had since grown through the entire thickness of the original weld and into the overlay material (through-wall).

Upon review of the licensee's corrective actions in CR 10058892, the inspectors identified that the licensee had only focused on addressing the non-destructive examination requirements associated with the 10-year ISI interval, and no consideration was given to the fact that the actual configuration was less robust than originally thought.

Thus, the licensee also failed to consider the current condition of the flaw that existed in the N2E safe end-to-nozzle weld since October 1988. As part of their investigation, the licensee sent the UT examination data from the previous exam (1R22, February 2006) to EPRI for further analysis. EPRI determined that although the licensee's exam was adequate in all respects using 2006 technology and requirements, with EPRI's updated technology and experience, the data suggested that the crack had already grown into the overlay material at that time.

Analysis:

The failure of the licensee to promptly identify a nonconformance (through-wall flaw in ASME Class 1 RCS piping) was a performance deficiency. The performance deficiency was more than minor because it was associated with the Equipment Performance attribute of the Initiating Events cornerstone and adversely affected the cornerstone objective of limiting the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. The inspectors screened this finding using IMC 0609, Appendix A, "The Significance Determination Process (SDP) For Findings At-Power," dated June 19, 2012. Because the finding involved the potential for a Loss of Coolant Accident (LOCA), further evaluation using Exhibit 1, "Initiating Events Screening Questions" was required. Because after a reasonable assessment of degradation, the finding could neither result in exceeding the RCS leak rate for a small LOCA, nor likely affected other systems used to mitigate a LOCA resulting in a total loss of their function, the finding screened as Green. This finding has a cross-cutting aspect of Challenge the Unknown in the area of Human Performance (H.11) because upon discovery of a less robust configuration of the N2E nozzle overlay in April 2015, the licensee failed to consider the implications on the flaw that had existed in that component since 1988.

Enforcement:

Title 10 CFR 50 Appendix B Criterion XVI, "Corrective Actions," states, in part, that "Measures shall be established to assure that conditions adverse to quality, such as failure, malfunctions, deficiencies, deviations, defective material and equipment, and nonconformances are promptly identified and corrected." Contrary to the above, on April 21, 2015, the licensee failed to promptly identify a nonconformance associated with an ASME Class 1 component (through-wall flaw in the N2E nozzle weld, which exceeded ASME Section XI limits, as required by 10 CFR 50.55a). The potential safety consequence of operating at full power with this type of ASME nonconformance is a challenge to the integrity of the reactor coolant pressure boundary, which increases the likelihood of a LOCA. Upon discovery of the flaw condition in February 2016, the licensee entered the condition into their CAP as CR 10058892 and installed the appropriate FSWOL, which restored compliance. The licensee has entered this issue into their CAP as CR 10247856. This violation is being treated as an NCV consistent with Section 2.3.2 of the Enforcement Policy. (NCV 05000321/2016010-02, "Failure to Identify N2E Nozzle Weld Through-Wall Flaw")

4OA6 Meetings

On July 14, 2016, the inspectors presented the inspection results to Mr. James Collins, Site Licensing, of your staff. The inspectors confirmed that all proprietary information reviewed during the inspection was returned and that none of the potential report input discussed was considered proprietary. ATTACHMENT:

SUPPLEMENTARY INFORMATION

KEY POINTS OF CONTACT

Licensee

J. Collins, Site Licensing Manager

A. Gordon, Site ISI Program Engineer

NRC

B. Collins, Reactor Inspector

D. Hardage, Senior Resident Inspector

D. Retterer, Resident Inspector

LIST OF ITEMS OPENED, CLOSED, DISCUSSED AND UPDATED

Opened

05000321/2016010-01 AV Inaccurate Information Provided Regarding N2E Nozzle

Weld Overlay

Closed

05000321/FIN-2016001-01 URI Reactor Coolant System N2E Weld Flaw

05000321/LER-2016-003 LER Reactor Coolant System Piping Has Unacceptable Weld Indication Discovered During Refueling Outage

Opened and Closed

05000321/2016010-02 NCV Failure to Identify N2E Nozzle Weld Through-Wall Flaw

LIST OF DOCUMENTS REVIEWED

Corrective Action Documents

263280, Apparent Cause Determination: Failure to Adequately Monitor and Repair a Defect in

1B31-1RC-12BR-E-5, dated 3/25/16

CR10058892: 1B31 Safe End Nozzle Welds, dated 4/21/15 CR10197850: Incorrect Information Submitted to NRC, dated 3/16/16 CR10247856: Violation of 10

CFR 50 Appendix B Criterion XVI, dated 7/13/16

Work Orders/Work Requests: SNC685755, Work Order: Install Full-Structural Weld Overlay on N2E Nozzle (1B31-1RC-12BR-

E-5), dated 7/17/2015

Miscellaneous

Documents:

HL-5045, Letter from J. T. Beckham, Jr. to Nuclear Regulatory Commission, "Edwin I. Hatch Nuclear Plant, Third 10-Year Interval Inservice Inspection Program," dated October 17, 1995

HL-5952, Letter from H.L. Sumner, Jr. to Nuclear Regulatory Commission, "Edwin I. Hatch

Nuclear Plant, Third 10-year Interval Inservice Inspection Program, Adoption of

BWRVIP-75," dated June 23, 2000

NL-15-1146, Letter from C.R. Pierce to Nuclear Regulatory Commission, "Edwin I. Hatch Nuclear Plant - Unit 1, Proposed Alternative in Accordance with 10

CFR 50.55a (z)(1)

Application of Dissimilar Weld Full-Structural Weld Overlays," dated July 2, 2015

NL-16-0421, Letter from C.R. Pierce to Nuclear Regulatory Commission, "Edwin I. Hatch

Nuclear Plant - Unit 1, Full Structural Weld Overlays on Reactor Recirculation and Residual Heat Removal Systems, Nondestructive Examination Results - Spring 2016 Outage (1R27)," dated March 17, 2016

NL-5940, Letter from H.L. Sumner, Jr. to Nuclear Regulatory Commission, "Edwin I. Hatch Nuclear Plant - Unit 1, Reactor Coolant System (RCS) Weld Overlay Examinations," dated

May 30, 2000