ML24366A161

Operating Corporations (Wcnocs) Contest Response to Non-Cited Violation 2024003-01 - NRC Inspection Report 05000482/2024003

ML24366A161
Person / Time
Site:	Wolf Creek
Issue date:	12/31/2024
From:	Boyce M Wolf Creek
To:	Office of Nuclear Reactor Regulation, NRC Region 4, Document Control Desk
References
000729 IR 2024003
Download: ML24366A161 (1)

Text

P.O. Box 411 l Burlington, KS 66839 l 620-364-8831 Michael T. Boyce Vice President Engineering December 31, 2024 000729 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001

References:

1) NRC inspection report dated November 01, 2024, from A. N. Agrawal (USNRC) to C. O. Reasoner (WCNOC), Wolf Creek Generating Station -

Integrated Inspection Report 05000482/2024003 (NRC ADAMS ML24295A379)

2) Letter 000713, dated November 27, 2024, from D. T. Hamman (WCNOC) to U.S. NRC, Notice of Intent to Contest Non-Cited Violation (NCV)05000482/2024003-01, and Request for Additional Time to Provide Wolf Creek Nuclear Operating Corporations (WCNOC) NCV Response (NRC ADAMS ML24332A126)

Subject:

Docket No. 50-482 and License No. NPF-42: Wolf Creek Nuclear Operating Corporations (WCNOCs) Contest Response to Non-Cited Violation 2024003 NRC Inspection Report 05000482/2024003 Commissioners and Staff:

Pursuant to 10 CFR 50.4, and in accordance with guidance in the Nuclear Regulatory Commissions (NRC) Enforcement Policy, Wolf Creek Nuclear Operating Corporation (WCNOC) hereby contests the very low safety significance, Green, Non-Cited Violation (NCV) described in Reference 1 for Failure to Remove Motor-Operated Valve Thermal Bypass Jumpers during Surveillance Testing and System Maintenance. Reference 2 documents the request for a response extension to December 31, 2024.

While licensees are not required to provide written responses to NCVs, WCNOC respectfully disputes the NCV due to the potential adverse impact with reliability of safety-related motor operated valves (MOVs). The current practice of leaving jumpers installed during surveillance testing ensures the MOVs are tested in their design basis configuration. Implied corrective actions needed to address the NCV would be adverse to the current surveillance practice, which ensures reliability of equipment needed to maintain high levels of nuclear safety in the event of a postulated design basis accident.

In addition to ensuring safety-related MOV reliability for maintaining a high level of nuclear safety, Wolf Creek Generating Stations (WCGSs) current surveillance practice is in full compliance with its current licensing basis as established by Section 8.3.3.1.2 in the 1985 Safety Evaluation Report (SER) for WCGS, NUREG 0881 Supplement No. 5. The SER describes and requires WCGSs use of jumpers with thermal overload relays (TOLs) for safety-related MOVs for meeting

000729 Page 2 of 2 P.O. Box 411 l Burlington, KS 66839 l 620-364-8831 position 1(a) of Regulatory Guide (RG) 1.106 Revision 1 (R1), dated March 1977. To achieve the RG 1.106 R1 goal of ensuring TOLs do not impede an MOVs safety function, permanent installation of jumpers was performed prior to initial loading of fuel and start of WCGS commercial operation in 1985, in lieu of adding the TOLs to the plant Technical Specifications.

Since the original licensing basis for TOL jumper installation established by the 1985 SER, WCGS has made no new commitments related to TOLs. WCNOC believes NCV 05000482/2024003-01 is imposing a change in WCNOCs licensing basis use of TOL jumpers with safety-related MOVs in a way that imposes backfit on the station without going through the appropriate 10 CFR 50.109 backfit process. Per the 10 CFR 50.109 Backfit Rule, specifically 10 CFR 50.109(a)(1)(iii), the NCV represents the imposition of a regulatory staff position interpreting the Commissions regulations, that is different from a previously applicable staff position, after the date of issuance of the operating license.

In response, information attached to this letter explains WCGSs licensing basis and how WCGS is meeting regulatory requirements to ensure continued protection of the health and safety of the public.

This letter contains no commitments. If you have any questions concerning this matter, please contact me at (620) 364-8831 x8687, or Dustin Hamman at (620) 364-4204.

Sincerely, Michael T. Boyce MTB/jkt

Wolf Creek Response to Non-Cited Violation 05000482/2024003-01 : Copy of Non-Cited Violation from Wolf Creek Generating Station -

Integrated Inspection Report 05000482/2024003 : Timeline of Relevant Documents : Supplemental TOL Explanatory Information : Additional Context from NUREG-1296 and Regulatory Guide 1.106, Revision 2

NUREG-0881 Supplement 5, WCGS Safety Evaluation Report Page 8-3 with Section 8.3.3.1.2 Thermal-Overload Protection Bypass (February 1985) :

Position on Thermal Overload Protection in WCNOC-85 and AP 23D-001 :

Drawing E-K3EF03, Schematic Diagram Screen Wash Water Valves cc:

A. N. Agrawal (NRC), DORS, Branch Chief B, Region IV, w/a, w/e S. S. Lee (NRC), NRC Project Manager for WCGS, w/a, w/e G. B. Miller (NRC), Director, Division of Operating Reactor Safety, Region IV, w/a, w/e J. D. Monninger (NRC), Regional Administrator, Region IV, w/a, w/e D. L. Pelton (NRC), Director, Office of Enforcement, w/a, w/e Senior Resident Inspector (NRC), w/a, w/e WCNOC Licensing Correspondence ET 24-000729, w/a, w/e

to 000729:

WCNOC Response Contesting Violation 05000482/2024003-01 28 Pages to 000729 Page 1 of 28 Table of Contents 1

NCV Summary Statement................................................................................................... 2 2

WCNOC Executive Summary Response............................................................................. 2 2.1 Reinterpretation 1:....................................................................................................... 2 2.2 Reinterpretation 2:....................................................................................................... 3 2.3 Backfit Analysis Consideration:.................................................................................... 3 3

WCNOC Response Contesting Non-Cited Violation 05000482/2024003-01....................... 4 3.1 WCNOC is not required to always remove TOL jumpers during testing....................... 5 3.2 MOV testing does not include surveillance and post-maintenance operability testing.. 9 3.3 Approved design does not threaten Mitigating Systems requirements........................13 3.4 WCNOC Response to NCV 05000482/2024003-01....................................................15 4

Backfit Analysis Consideration...........................................................................................25 4.1 WCNOC Backfit Analysis Request..............................................................................25 5

WCNOC Conclusion..........................................................................................................28 to 000729 Page 2 of 28 1

NCV Summary Statement The inspectors identified a Green finding and associated non-cited violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, for the licensees failure to assure the applicable design requirements associated with the licensees commitment to Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves, revision 1, was correctly translated into procedures and instructions. Specifically, the licensee failed to translate that the thermal overloads be placed in force during stroking of safety-related motor-operated valves for surveillance testing and routine maintenance into procedures and instructions.

Non-Cited Violation (NCV)05000482/2024003-01 is reproduced in full in Attachment 2 and will henceforth be referred to as the NCV.

2 WCNOC Executive Summary Response Wolf Creek Nuclear Operating Corporation (WCNOC) asserts that this NCV is based on two fundamental reinterpretations of Wolf Creek Generating Stations (WCGSs) approved licensing basis. These reinterpretations are:

Reinterpretation 1:

That WCGS shall always remove Thermal Overload Relay (TOL) jumpers during testing.

Reinterpretation 2:

That motor-operated valve (MOV) periodic or maintenance testing, as used in Regulatory Guide (RG) 1.106, Revision 1 (R1), includes surveillance and post-maintenance operability testing.

2.1 Reinterpretation 1:

WCNOC asserts that it is not required to always remove TOL jumpers during testing. WCNOC is committed to Nuclear Regulatory Commission (NRC) RG 1.106 R1, issued in March 1977, utilizing Regulatory Position 1(a). The Safety Evaluation Report (SER) for Wolf Creek Generating Station (WCGS), documented in NUREG-0881 Supplement 5, issued in March 1985, established that Class 1E valve motors with TOLs would be permanently bypassed prior to initial fuel loading with no requirement for removal during surveillance testing. The NRC staff approved this approach during WCNOCs licensing application process, noting that the use of TOLs during testing is a prudent operational practice but only a staff observation, not a requirement. The NRCs reinterpretation that jumpers must always be removed for MOV testing, including surveillance and post-maintenance operability testing, is inconsistent with WCNOCs original licensing basis and commitments.

WCNOCs review of applicable licensing basis documents, including responses to Generic Letter 89-10, confirmed no new commitments related to the removal of TOL jumpers during testing.

WCNOCs MOV program, originally documented in WCNOC-85 and AP 23D-001, consistently stated that TOL jumpers would remain continuously installed, except during testing, without implying a requirement for removal for all testing. The NRCs claim of a new commitment is unfounded and does not reflect WCNOCs established licensing basis or documented commitments. WCNOCs practices and procedures have adhered to the original interpretation of RG 1.106 R1, Position 1(a), and any deviation should not be assumed without explicit agreement from WCNOC.

to 000729 Page 3 of 28 Per 5.1.3.4 in NUREG 1409, the NRC can establish facility-specific staff positions through safety evaluations or safety evaluation reports. In WCNOCs case, the SER Section 8.3.3.1.2 establishes the permanently installed jumpers were a condition for gaining approval for an operating license without placing the TOLs into the plants Technical Specifications (TS). WCNOC further incorporated the permanently installed jumpers into design documents, such as drawing E-K3EF03, which contains Note 6 Jumper to be installed prior to core loading. Therefore, by requiring removal of jumpers for surveillances, the NCV is changing WCGSs licensing basis given in NUREG 0881 Supplement No. 5, which makes the NCV subject to a backfit analysis. Per the 10 CFR 50.109 Backfit Rule, specifically 10 CFR 50.109(a)(1)(iii), the NCV represents the imposition of a regulatory staff position interpreting the Commissions regulations, that is different from a previously applicable staff position, after the date of issuance of the operating license for the facility having an operating license.

2.2 Reinterpretation 2:

WCNOC asserts that MOV periodic or maintenance testing, as used in RG 1.106 R1, does not include TS required surveillance testing and post-maintenance operability testing. RG 1.106 R1 does not define valve motors are undergoing periodic or maintenance testing, and WCNOC maintains that the guide does not mandate the removal of TOL jumpers during testing, rather it allows the practice. The NRC's reinterpretation uses a definition of maintenance from a newer and different regulatory guide, RG 1.160 R4, developed years after the issuance of WCGSs SER and operating license.

Applying a definition from RG 1.160 R4 to reinterpret the intent of RG 1.106 is inappropriate and inconsistent with the original purpose and scope of these regulatory guides. The commitments made by WCNOC were based on the regulatory guides and definitions in effect at the time of licensing. Reinterpreting these commitments using later definitions from a different RG violates the principle of regulatory finality and undermines the regulatory certainty essential for safe and compliant plant operations. The newer RG 1.160 R4 does not retroactively apply to the committed to RG 1.106 R1, and the original definitions and interpretations at the time of initial licensing should remain applicable.

The NRCs broad interpretation that TOL jumpers must be removed for all TS required surveillance and post-maintenance operability testing would render RG 1.106 R1 position 1(a) potentially impossible to implement. Attempting to comply with this reinterpretation would require numerous clearance orders and unnecessary out-of-service time, increasing plant risk substantially more than any potential gain. Bypassing TOLs during surveillance stroke tests, as allowed by RG 1.106 R1, does not present an elevated risk and testing MOVs in their safety-related configuration ensures they can perform their safety function during an accident.

2.3 Backfit Analysis Consideration:

RG 1.106 R1, provides guidance on thermal overload protection for electric motors on MOVs.

Position 1(a) outlines acceptable methods for ensuring that thermal overload protection devices do not prevent the motor from performing its safety-related function. WCNOC has consistently interpreted this guidance to mean that thermal overload bypass jumpers shall be continuously installed and are not required to be removed for all surveillance and post-maintenance operability testing. Our procedures and instructions have been developed in accordance with this interpretation, which has been previously accepted by the NRC.

to 000729 Page 4 of 28 WCNOC contends that the NRC has reinterpreted RG 1.106 R1, Position 1(a), and the approved WCGS licensing basis in a manner inconsistent with original commitments. WCNOCs licensing basis, as documented in our Updated Safety Analysis Report (USAR) and other licensing documents, does not include a commitment to remove thermal overload bypass jumpers for all surveillance and post-maintenance operability testing of safety-related MOVs. The NRCs current interpretation represents a new or different regulatory position, which constitutes a backfit under 10 CFR 50.109(a)(1)(iii).

Implementing the corrective actions suggested by the NCV does not appear to be possible while continuing to ensure the operability of safety-related MOVs following intrusive rewiring. With no clear path to compliance, the reinterpretation of WCGSs approved licensing basis may force WCGS into adopting a different RG 1.106 R1 position, which would require a license amendment, the creation of new TS, and design changes to the plant. If corrective actions were to be developed to comply with this reinterpretation of Position 1(a), removing the TOL jumpers during surveillance and post-maintenance operability testing would ultimately make the plant less safe, increase unavailability time, and unnecessarily increase risk and cost to the station, with no increase in the protection of public health and safety.

WCNOC respectfully requests that the NRC reconsider the issuance of NCV 05000482/2024003-

01. WCNOC believes that current practices are consistent with the WCGS approved licensing basis and RG 1.106 R1. WCNOC seeks a resolution that acknowledges our compliance with the established regulatory framework and avoids unnecessary and unjustified burdens on our operations. If the NRC upholds this reinterpretation and determines that a Performance Deficiency exists, WCNOC requests that the NRC conduct a thorough backfit analysis to evaluate the necessity and impact of this new interpretation, as required by 10 CFR 50.109(a)(2).

3 WCNOC Response Contesting Non-Cited Violation 05000482/2024003-01 provides a timeline of relevant documents detailed in this response and Attachment 4 provides supplemental explanatory information to help the reader understand the thermal overload relay (TOL) circuitry and design.

Thermal overload protection devices are designed to prevent damage to motors by shutting them off if they overheat due to excessive current or prolonged operation. However, for safety-related motor-operated valves (MOVs) in nuclear plants, the primary concern is ensuring the valve motors operate during accident conditions, even if they overheat. Continuously bypassing the protection ensures the valve motors are not inadvertently disabled during critical operations, allowing them to fulfill their safety function (e.g., isolating a pipe or ensuring cooling water flow). During periodic or maintenance testing, when the safety function of the valve is not immediately needed, the thermal overload protection can be temporarily re-enabled. This is an allowance, not a requirement.

Further, testing the valve in its design safety configurationbypassing the thermal overload protection as it would be during an accidentis critical to ensure the valve performs its safety function. While enabling thermal protection may be prudent during some non-safety-critical maintenance or testing, the priority in safety-related systems is always to validate operability under accident conditions.

to 000729 Page 5 of 28 3.1 WCNOC is not required to always remove TOL jumpers during testing WCNOC is committed to NRC RG 1.106 R1, issued in March 1977, Regulatory Position 1(a).

WCGS SER (NUREG-0881) Supplement 5 was issued in March 1985. As described by the SER, thermal overload relay trip contacts for all Class 1E valve motors with TOLs will be permanently bypassed with jumpers before fuel loading. There was no discussion of removal for surveillance testing. The NRC staff approved the use of permanently bypassed TOLs during WCNOCs licensing application process. The wording stated that the use of TOLs (i.e., removing the bypass jumpers) during testing is a prudent operational practice, but that this is only a staff observation.

Prior to using the approach of bypassing the TOLs, in the original Final Safety Analysis Report (FSAR) submitted by both SNUPPS plants (Callaway and WCGS), it was stated that thermal overload protective devices for Class 1E valves are included, and that the calibration of the relays will be checked during each refueling period to ensure an adequate setpoint margin.

In NUREG-0881, Safety Evaluation Report Related to the Operation of Wolf Creek Generating Station, Unit No. 1, Section 8.3.3.1.2, Thermal-Overload Protective Bypass the NRC documented the above approach, and added:

The setpoints for the thermal overload protection, their required margin, and the frequency for periodic tests will be included in the Technical Specifications.

In Revision 10 of the Final Safety Analysis Report (FSAR) submitted by both SNUPPS plants (Callaway and WCGS), both plants indicated that the thermal overload relay trip contacts for all Class 1E valves would be permanently bypassed with jumpers before fuel loading. In Supplement 5 to NUREG-0881, the NRC acknowledged this approach to thermal overload protection, adding:

The staff concludes that the permanent bypass resolves the original SER concern relating to inadvertent operation of thermal overloads under accident conditions; thus, Technical Specifications for this item are no longer required.

The staff notes, however, that it is not the intent of RG 1.106 to totally eliminate the use of thermal overloads on motor-operated valves. RG 1.106 is intended to ensure that, under accident conditions, the valve will not be hindered from performing its safety function by a spurious trip of its thermal overload protective circuits. For the majority of valve operations such as during valve tests or operation during nonaccident conditions, the use of thermal overload protective circuits is a prudent operational practice to minimize motor damage as a result of overload. This is only a staff observation, and it is not considered an open or confirmatory item.

In the Introduction section of RG 1.106 R1, the following is stated:

This regulatory guide describes a method acceptable to the NRC staff for complying with the above criteria with regard to the application of thermal overload protection devices that are integral with the motor starter for electric motors on motor-operated valves. This method would ensure that the thermal overload protection devices will not needlessly prevent the motor from performing its safety-related function. The Advisory Committee on Reactor Safeguards has been consulted concerning this guide and has concurred in the regulatory position.

In the Discussion section of RG 1.106 R1, the following is stated:

to 000729 Page 6 of 28 Operating experience has shown that indiscriminate application of thermal overload protection devices to these valve motors could result in needless hindrance to successful completion of safety functions. Thermal overload relays are designed primarily to protect continuous-duty motors while they are running rather than during starting. Use of these overload devices to protect intermittent-duty motors may therefore result in undesired actuation of the devices if the cumulative effect of heating caused by successive starts at short intervals is not taken into account in determining the overload trip setting.

In the Regulatory Position section of RG 1.106 R1, the following is stated in regulatory position 1:

In order to ensure that safety-related motor operated valves whose motors are equipped with thermal overload protection devices integral with the motor starter will perform their function, one of the two alternatives described in regulatory position 1 or the one described in regulatory position 2 should be implemented:

1. Provided that the completion of the safety function is not jeopardized or that other safety systems are not degraded, (a) the thermal overload protection devices should be continuously bypassed and temporarily placed in force only when the valve motors are undergoing periodic or maintenance testing (this is the position that WCNOC adopted) or (b) those thermal overload protection devices are normally in force during plant operation should be bypassed under accident conditions.

The bypass initiation system circuitry should conform to the criteria of Sections 4.1, 4.2, 4.3, 4.4, 4.5, 4.10, and 4.13 of IEEE Std 279-1971, Criteria for Protection Systems for Nuclear Power Generating Stations, and should be periodically tested.

2. The trip setpoint of the thermal overload protection devices should be established with all uncertainties resolved in favor of completing the safety-related action. With respect to those uncertainties, consideration should be given to (a) variations in the ambient temperature at the installed location of the overload protection devices and the valve motors, (b) inaccuracies in motor heating data and the overload protection device trip characteristics and the matching of these two items, and (c) setpoint drift. In order to ensure continued functional reliability and the accuracy of the trip point, the thermal overload protection device should be periodically tested.

RG 1.106 R1 continues:

This guide reflects current NRC staff practice. Therefore, except in those cases in which the applicant proposes an acceptable alternative method for complying with specified portions of the Commissions regulations, the method described herein is being and will continue to be used in the evaluation of submittals for construction permit applications until this guide is revised as a result of suggestions from the public or additional staff review.

It is WCNOCs position that the plain language of RG 1.106 R1, issued March 1977, does not state that jumpers SHALL ALWAYS be removed for periodic or maintenance testing. Its plain language intent is that the jumpers SHALL ALWAYS be installed, and MAY ONLY be removed for periodic or maintenance testing, at the utilitys choice, and as described by Supplement 5 to NUREG-0881, this is only a prudent operational practice. (WCNOC does, in fact, remove the TOL jumpers for MOV maintenance testing, in accordance with its MOV program guidance.)

to 000729 Page 7 of 28 WCGS SER (NUREG-0881) Supplement 5, issued in March 1985, states:

WCNOC clearly stated the Class 1E valve motors with TOLs will be permanently bypassed.

There is no discussion of removal for surveillance testing. The NRC staff clearly approved the use of permanently bypassed TOLs. The wording states that the use of TOLs (i.e., removing the bypass jumpers) during testing is a prudent operational practice, but that this is only a staff observation.

It is clear that WCNOCs original licensing basis does NOT require the removal of jumpers that bypass TOLs on MOVs. There has been no regulatory requirement or process utilized (no rule making, no generic letters, etc.) that would require WCNOC to revise its original licensing basis regarding bypassing TOLs in MOVs.

The NRCs reinterpretation of this language instead implies that jumpers MUST ALWAYS be removed for motor testing and also that motor testing broadly includes any and all surveillance and post-maintenance operability testing that may cause the MOVs to stroke. WCNOC disagrees with both assertions.

Prior to receiving the NCV, WCNOC reviewed applicable licensing basis documents to ensure no new commitments related to the removal of TOL jumpers during testing had been made by WCNOC following the issuance of the SER. This was repeated following the issuance of the NCV.1 This review included the numerous Generic Letter (GL) 89-10, Safety-Related (1) Motor-Operated Valve Testing and Surveillance (Generic Letter No. 89-10) - 10 CFR 50.54(f),

responses and commitments from the 1989 to 1995 time-period. No new commitments related to TOL jumpers were identified. Instead, a review of the stations GL 89-10 responses confirmed that WCNOC remained clearly committed to its original licensing basis position and interpretation of RG 1.106 R1, Position 1(a).

In response to GL 89-10, WCNOC developed an MOV program. This MOV program was originally documented in WCNOC-85, Motor Operated Valve Program Description, Revision 0, dated June 18, 1992, and was later documented in AP 23D-001, Motor Operated Valve Program, Revision 0, released September 21, 1994. WCNOC-85, which initially outlined the MOV program, was provided to the NRC in response to GL 89-10. Following the release of Revision 0 in 1992, it was revised three times with Revision 3 being released November 15, 1993.

to 000729 Page 8 of 28 All four versions of WCNOC-85 noted the following under a section titled Position on Thermal Overload Protection (this section is provided in Enclosure 2 of this letter):

The use of a thermal overload device however, is only one alternative method of ensuring that the condition of a valve actuator motor does not deteriorate over time. Another viable alternative is to use diagnostic test equipment such as VOTES (Valve Operation Test and Evaluation System) for trending motor performance to ensure that there is no appreciable degradation over time.

Currently, Wolf Creek is committed to Regulatory Guide 1.106 R1, Section C, Regulatory Position 1(a), which states that thermal overload protection devices should be continuously bypassed and temporarily placed in force only when the valve motors are undergoing periodic or maintenance testing. This position advocates a compromise in favor of completing the safety related action rather than protecting a motor where a choice must be made.

Based on original commitment to Regulatory Guide 1.106 R1, and the inherent inaccuracies of these devices, Wolf Creeks philosophy will remain the same in regard to thermal overload protection of safety related MOVs. Specifically, since the degree of accuracy required in this application is not realistically achievable with these devices, and there is no logical reason to provide a thermal overload device that in all probability will not trip under any circumstances, all contacts will remain bypassed except during testing.

Justification for this philosophy is provided by a comprehensive tracking and trending program to be implemented with the release of WCNOC-85. Under this program, VOTES testing will be performed at specified intervals to monitor actuator motor performance and preclude excessive motor degradation.

This language was again duplicated in the initial release of AP 23D-001, Motor Operated Valve Program, Revision 0, in Attachment F (also provided in Enclosure 2 of this letter).

As part of WCNOCs GL 89-10 response, WCNOC made an explicit statement using plain language that the WCNOC TOL philosophy will remain the same. WCNOC noted that TOL jumpers will remain continuously installed, with the exception of during testing. This plain language statement did not imply that TOL jumpers must be removed for all testing and introduced no new commitment to remove TOL jumpers for surveillance and post-maintenance operability testing. It simply restated the language in RG 1.106 R1, Regulatory Position 1(a), and reinforced our unchanged commitment to that position.

In discussions with the NRC prior to receiving the NCV, the NRC stated that GL 89-10 backfitted our original RG 1.106 R1 position. It is inappropriate for the NRC to infer a new commitment from WCNOC's words where no explicit commitment was made. WCNOC has not committed to a new interpretation of RG 1.106 R1, Regulatory Position 1(a). Any such claim by the NRC is unfounded and does not reflect our established licensing basis or documented commitments. Our practices and procedures have consistently adhered to the original interpretation, and any deviation from this should not be assumed without clear, explicit agreement from WCNOC.

1While reviewing historical documents related to the application of thermal overloads with MOVs, it became clear that there was internal debate inside the NRC on this topic after RG 1.106 R1 was released. NUREG-1296, was issued by the NRC in June 1988, which provided additional information from the Office for Analysis and Evaluation of Operational Data (AEOD) in response to concerns related to RG 1.106 R1. Later, in February 2012, the NRC issued RG 1.106 R2.

It noted, however, Current licensees may continue to use guidance the NRC found acceptable for complying with the to 000729 Page 9 of 28 identified regulations as long as their current licensing basis remains unchanged. Additional relevant context from NUREG-1296 and RG 1.106 R2 is provided in Attachment 5 of this letter.

3.2 MOV testing does not include surveillance and post-maintenance operability testing MOV periodic or maintenance testing, as used in RG 1.106 R1, and as historically interpreted by the NRC at WCGS, does not include TS required surveillance testing and post-maintenance operability testing.

3.2.1 Current procedural requirements of removing TOL jumpers at WCGS It is critical to note that RG 1.106 R1 does not define valve motors are undergoing periodic or maintenance testing. While it is WCNOCs position that RG 1.106 R1 does not state jumpers SHALL be removed, if it were interpreted in that way by the NRC it would then lead to needing a definition of valve motors are undergoing periodic or maintenance testing to properly implement.

As the intent is to have the TOLs bypassed, and jumpers ONLY removed when valve motors are undergoing periodic or maintenance testing, it would be critical for utilities to not unnecessarily remove the jumpers for testing that does not meet this requirement, such as post-maintenance operability testing.

WCNOC previously received a Green NCV in 2013 during a Component Design Basis Inspection (CDBI) related to removing TOL jumpers during MOV periodic testing. The violation was documented in Inspection Report 05000482/2013008 (NRC ADAMS ML13326A477). Excerpts from the NCV include the following:

The licensee failed to translate the requirements into Procedure MGE LT-099, MOV Diagnostic Testing, and failed to include procedural guidance to remove the thermal overload bypass jumpers when performing maintenance testing that strokes the valve from the control room.

The team determined that the licensees failure to provide procedure instructions to remove the thermal over-load bypass jumpers during motor-operated valve diagnostic testing as committed to in Regulatory Guide 1.106, Revision 1, was a performance deficiency.

While WCNOC contends that there is no such explicit requirement in RG 1.106 R1 to enable TOLs during maintenance testing, it remains clear that the NRC did not include TS required surveillance testing and post-maintenance operability testing in the maintenance testing definition used at the time of the 2013 NCV. The NRC instead directed the performance deficiency at the failure to incorporate the requirement to enable TOLs into the MGE LT-099, MOV Diagnostic Testing, procedure, rather than the myriad of TS required surveillances that stroke MOVs or the numerous MOV stroke procedures used to ensure MOV operability following maintenance.2 From the language in the 2013 NCV, it can be inferred that the NRC was primarily concerned with MOV periodic or maintenance testing that relied on Control Room Operators to end a valve stroke if a valve experienced an overthrust or locked rotor condition. Following the NCV in 2013, WCNOC was forced to develop a periodic / maintenance testing definition, because there is no clear definition in RG 1.106 R1. WCNOC revised MGE LT-100, Limitorque Valve Operator General Notes & Details, to include the following definition:

Maintenance Testing is to be defined by the performance of activities associated with Maintenance Procedures, and/or Maintenance Work instructions that REMOVE the Limit Switch Compartment cover on Safety-Related MOV's with Thermal Overload (TOL) bypass jumper.

to 000729 Page 10 of 28 MGE LT-100, Limitorque Valve Operator General Notes & Details, requires that the thermal overload protection devices be continuously bypassed and temporarily placed in force when the valve motors are undergoing periodic or maintenance testing per this definition.

Rather than relying on TOLs to ensure that there is no appreciable degradation over time, WCNOC periodically employs diagnostic test equipment, such as Valve Operation Test and Evaluation System (VOTES) testing, at specified intervals. This periodic VOTES diagnostic testing is described in detail in MGE LT-099, MOV Diagnostic Testing, and is used to monitor actuator motor performance and preclude excessive motor degradation. This was originally described in WCNOC-85, Motor Operated Valve Program Description following GL 89-10 and remained unchanged following the 2013 NCV.

2It is notable that in interviews with an individual involved with the inspection in 2013, the individual recalled internal disagreement amongst the inspection team on the proper interpretation of position 1(a) of RG 1.106 R1 and the associated proposed finding. In response to the NCV, historical documents show that WCNOC elected to revise the few MOV maintenance testing procedures that performed MOV maintenance testing without directing removal of the TOL jumpers, rather than contest the NCV. At the time, WCNOC already routinely removed TOL jumpers while performing MOV maintenance and diagnostic testing that employed dead-man switches. (This did not and does not include the post-maintenance operability test following the MOV maintenance testing.)

3.2.2 Definition of valve motors are undergoing periodic or maintenance testing For the 2024 NCV, to obtain a definition of maintenance that included surveillance and post-maintenance operability testing, the NRC referred to RG 1.160 R4, titled Monitoring the Effectiveness of Maintenance at Nuclear Power Plants. The NRC then applied the definition in RG 1.160 R4, to the plain language in RG 1.106 R1, to make the assertion that periodic or maintenance testing, as used in RG 1.106 R1, includes routine surveillance and post-maintenance operability testing.

RG 1.106 R1, titled "Thermal Overload Protection for Electric Motors on Motor-Operated Valves,"

was published in March 1977. In contrast, RG 1.160, R4, titled "Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," was published in September 2018. Revision 0 of RG 1.160 was issued in June 1993. The NRC further clarified in the NCV that the definition of maintenance found in RG 1.160 was obtained from the Federal Register (FR) notice, Final Commission Policy Statement on Maintenance at Nuclear Power Plants, which was dated March 23, 1988. To recap, RG 1.106 R1, which WCNOC is committed to, was published in March 1977, the WCGS SER (NUREG-0881) Supplement 5 was issued in March 1985, (WCNOCs operating license was issued in June 1985), and the earliest example of the definition of maintenance used in the NCV was written in March 1988.

The attempt by the NCV to reinterpret the wording in a regulatory guide that our station committed to during initial plant licensing, using definitions from a regulatory guide developed years after the issuance of our SER and operating license, is fundamentally flawed and unjustifiable. The regulatory framework established at the time of our plant's licensing should remain consistent and stable. Introducing definitions from a later-developed regulatory guide undermines the regulatory certainty that licensees rely upon for compliance and operational planning.

Our station's commitments were made based on the regulatory guides and definitions in effect at the time of licensing. These commitments were reviewed and approved by the NRC, forming the basis of our SER and OL. Reinterpreting these commitments using later definitions violates the principle of regulatory finality. The NRC's own procedures and legal precedents support the to 000729 Page 11 of 28 notion that changes to regulatory interpretations should not be applied retroactively to previously issued licenses unless explicitly stated. Applying new definitions retroactively without proper rulemaking or license amendment processes is procedurally improper.

The reinterpretation of regulatory commitments using new definitions could lead to unnecessary confusion and potential non-compliance, adversely affecting plant safety and operations. It is crucial that regulatory interpretations remain aligned with the original licensing basis to ensure continued compliance and safety. RG 1.160 R4, does not retroactively apply to RG 1.106 R1.

Regulatory guides are intended to provide guidance and are not legally binding unless explicitly incorporated into a license or regulation. Therefore, unless there has been a specific regulatory action or license amendment that incorporates the newer definitions into the commitments made under RG 1.106, the original definitions and interpretations at the time of the initial licensing would remain applicable.

Further, the definition of maintenance found in RG 1.160, "Monitoring the Effectiveness of Maintenance at Nuclear Power Plants," serves a specific purpose and is applicable within a distinct regulatory context. RG 1.160 was developed to provide guidance on complying with the Maintenance Rule outlined in 10 CFR 50.65, which requires nuclear power plant licensees to monitor the performance or condition of structures, systems, and components (SSCs) to ensure they can fulfill their intended functions. It focuses on the overall effectiveness of maintenance programs to enhance plant safety and reliability by minimizing failures and ensuring the operability of safety-related equipment.

In contrast, RG 1.106 R1, "Thermal Overload Protection for Electric Motors on Motor-Operated Valves," was issued to provide specific guidance on protecting electric motors from thermal overloads. The intent of RG 1.106 is to ensure that MOVs are adequately protected against thermal overload conditions, thereby ensuring reliable operation of these critical components while performing their safety function. It is not concerned with ensuring TOL use during testing, certainly not surveillance and post-maintenance operability testing as neither are included in the RG.

The definition of maintenance in RG 1.160 is tailored to the broader context of monitoring and improving maintenance effectiveness across the entire plant, as required by the maintenance rule. It is not intended to retroactively apply to the specific technical guidance provided in RG 1.106, which addresses a different aspect of plant operation and safety.

Applying the definition of maintenance from RG 1.160 to reinterpret the intent of RG 1.106 is inappropriate and inconsistent with the original purpose and scope of these regulatory guides.

Each guide was developed to address distinct regulatory requirements and operational concerns, and their definitions and guidance should be applied within their respective contexts.

If the NRC concludes that WCNOC is required to remove TOL jumpers, which WCNOC contests and the RG 1.106 does not require, the plain language in RG 1.106 R1, does not then indicate that it would also be required, or acceptable, to remove the TOL jumpers during surveillance and post-maintenance operability testing. RG 1.106 R1, states, and temporarily placed in force only when the valve motors are undergoing periodic or maintenance testing. For additional context, prior to this statement in the RG, the following statement is made, In some plants, the thermal overload devices are bypassed during normal plant operation, except that they are temporarily placed in force when the valve motors are undergoing periodic testing. It is clear that position 1(a) was written in such a way as to allow plants that bypass their TOLs to realign them if desired for testing but seeks to only allow this during periodic or maintenance testing. There is to 000729 Page 12 of 28 very clearly no statement in the RG that includes surveillance or post-maintenance operability testing, and very clearly no statement in the RG that requires TOLs to be used during surveillance or post-maintenance operability testing. Again, RG 1.106 R1 is focused on ensuring that the safety related MOVs are capable of performing their safety function during a design basis event, without risk of an undesired actuation of the TOL devices. It was not intended to direct maintenance or testing practices.

3.2.3 Inability to comply with reinterpreted definition of periodic or maintenance testing While there is no detailed definition of MOV periodic or maintenance testing in RG 1.106 R1, simple logic can be employed to reason that manipulating TOL jumpers following surveillance testing and post-maintenance operability testing was not the intent of the RG.

The NCVs reinterpretation of the definition of valve motor periodic or maintenance testing broadly includes any and all surveillance testing that may cause the valves to stroke, as well as all operability testing following maintenance. WCNOC disagrees with both of these assertions.

Many of the valve stroke surveillances do not require TS entry and do not remove the safety-related equipment from service. When they do, it is usually for very short periods of time.

However, if the jumpers which bypass the TOLs must be removed for every surveillance in which the valve might operate, as this interpretation would mandate, this would require the following sequence:

1. Enter TS Condition prior to making system Inoperable

2. Place clearance order (CO), remove system from service, de-energize MOV

3. Open Motor Control Center Cubicle and remove jumpers from control circuitry

4. Remove CO and restore power to now Inoperable MOV

5. Perform TS required surveillance and stroke Inoperable MOV

6. Place second CO to de-energize Inoperable MOV again

7. Open Motor Control Center Cubicle and replace jumpers in control circuitry

8. Remove CO and restore power to Inoperable MOV

9. With this reinterpretation, unable to exit TS Condition due to inability to perform post-maintenance operability testing with TOL jumper installed in its safety position

10. System remains Inoperable without conclusively testing safety function following unnecessary intrusive maintenance This broad interpretation is clearly not correct, as it would render position 1(a) unable to be implemented in practice, with no clear way to restore operability following intrusive maintenance (rewiring inside the MOVs breaker cubicle). If there were a way to prove operability following testing, the evolution above would likely have to be performed dozens or even hundreds of times per year to comply with all TS required surveillance testing of safety related MOVs. Unnecessarily adding actual out of service time, and the increased potential for damage due to removing and replacing jumpers, would increase plant risk substantially more than any gain from changing our current RG 1.106 R1 position.

During the recurring surveillance testing of safety-related MOVs detailed above, there would have been no prior maintenance performed on the valve and the valve would have only been stroked to verify operation and comply with TS surveillance requirements. As an aside, while WCNOC maintains an incredibly safe clearance order process, this reinterpretation and the resulting numerous clearance order evolutions would unnecessarily increase risk to our personnel.

to 000729 Page 13 of 28 Bypassing TOLs during the surveillance stroke tests, as allowed by RG 1.106 R1, does not present an elevated risk that the motors will overheat. Removal of TOL jumpers for surveillance stroke tests carries more risk with respect to ensuring that the valves can carry out their safety function of stroking as required during an accident. There is an inherent risk of removing and reinstalling thermal overload jumpers because they may not be reinstalled properly. Frequent bypassing and reinstating thermal overload protection for MOVs could lead to stripped screws and broken lugs as a result of the repeated loosening and tightening of connections. When loosening and tightening these lugs, stress is placed on the termination lug, which may result in failure if done repeatedly. In addition, a subsequent stroke test would then be required to ensure that the jumper is landed appropriately and does not prevent valve movement. This reinterpretation would not allow for this post-maintenance operability testing to occur.

To summarize, with this broad interpretation, because jumpers would be removed then reinstalled (i.e., there was intrusive maintenance done in the breaker cubicle) a post maintenance test (PMT) would be required to demonstrate the operability of the valve prior to exiting the TS Condition.

But, if jumpers must be removed during ALL testing, jumpers would then have to be removed for the PMT, which leads to a circular loop that would make it impossible to exit the TS Condition for any plant committed to regulatory position 1(a).

There is an additional problem with this interpretation. The primary requirement for both positions 1(a) and 1(b) from RG 1.106 R1 is that the TOLs are bypassed during accident conditions.

Surveillance testing is meant to make sure that structures, systems, and components (SSCs) are capable of performing their intended function(s) in design basis conditions. This would mean that during surveillance testing, MOVs should be tested in the configuration they would be in when mitigating a design basis event (i.e., TOLs should be bypassed). Any damage occurring during testing, similar to any other testing, would result in identification, TS Condition entry, and repair.

This is desirable as it would be identified during planned testing and not during a Design Basis Accident. Removing the jumpers during surveillance testing does not test the MOV circuitry in the normal design configuration and may not identify potential failures. For instance, the MOV limit switch failure identified during Safeguards Actuation Testing in 2014, as referenced by the NCV as CR 81790, may not have been identified had the equipment not been tested in its safety function lineup with the TOL bypass jumper installed.

3.3 Approved design does not threaten Mitigating Systems requirements The NCV screening noted the following:

The inspectors determined the performance deficiency was more than minor because it was associated with the Configuration Control attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences. Specifically, the failure to place the thermal overloads in force during surveillance testing resulted in the 480 volt motor control center for EFHV0092 to heavily smoke when the motor-operated valve went to a locked rotor condition due to a limit switch failure in June 2014.

3.3.1 Historical event background During Safeguards Actuation Testing on March 29, 2014, Operators noticed that NG06EDF2, the 480V breaker cubical for EFHV0092 "B" Essential Service Water Screen Wash Water Valve at the Essential Service Water Pumphouse, was smoking. Operators notified the control room and were directed to open the breaker if it could be done so safely. The breaker was opened, and to 000729 Page 14 of 28 smoke coming from the 480VAC cubicle began to dissipate. Operators found that the valve actuator for EFHV0092 was hot to the touch.

A Basic Low Level (BLL) evaluation associated with condition report 81790 determined the cause of the event to be a failure of the MOV limit switch which resulted in the valve actuator motor remaining energized after reaching its desired position. This resulted in the motor running in a locked rotor condition.

Corrective actions were taken to address the cause of the MOV limit switch failure. Immediate actions under work order (WO) series 14-385283 included breaker testing, TOL replacement, valve and operator replacement, and the necessary supporting testing associated with such scope.

Examination of the breaker cubicle revealed heat damage to the TOLs which was determined to be the source of the smoke. The TOL relay assembly was replaced and the breaker cubicle was returned to service.

Condition report 81790 noted vendor contact providing allowance and approval to use Loctite 242 on the connection of concern in effort to prevent reoccurrence. Extent of condition was addressed by adding Loctite to SMB-000 actuators through WO series 23-489131.

3.3.2 Safety Functions are not jeopardized, and other safety systems are not affected by committing to position 1(a)

The issue that occurred in 2014 during Safeguards Actuation testing was attributed to a failure of the associated MOV limit switch. As a result of the failed limit switch, the motor remained in a locked rotor condition. WO 14-385283-001 identified that the thermal overload relays were melted as a result and were subsequently replaced. Corrective action was taken to fix the failed MOV limit switch.

The design of the TOL jumper and associated safety system is such that it does not negatively impact other systems. For this event, there was a failed component in the MOV, a single failure, which caused this event to occur. The failed MOV limit switch was put into the corrective action program with corrective actions taken to address the failure. The remainder of the safety train was not affected by this event, nor was the alternate safety train affected due to redundant train separation.

As noted above, several parts associated with the MOV were affected by the limit switch failure and were subsequently replaced. This does not indicate that the approved design and compliance with RG 1.106 R1 negatively affects the mitigating system capability. This event was determined to be the result of a component failure, the MOV limit switch, which was subsequently corrected on this MOV. Further, there is no clear evidence that the TOLs, if placed in service, would have actuated quickly enough during the Safeguards Actuation Testing to prevent the damage to the affected MOV components, as the TOLs are designed to mimic motor heat buildup in continuous duty motors. While only speculation, it is likely that ultimately either the motor windings or the TOLs would fail under prolonged locked rotor conditions, following the completion of the MOVs safety function. While smoke was observed during this event, components in the MOV motor control center (MCC) cubicles are UL listed, tested and are generally flame retardant, with self-extinguishing properties when heat is removed. Redundant trains are provided and train separation exists.

to 000729 Page 15 of 28 In this instance, only the TOL related components in the MCC cubicle specific to the valve were affected by the locked rotor current. There was no damage to surrounding equipment inside the MOV MCC cubicle. The TOLs were subsequently replaced prior to returning the MOV to service. of this letter provides further explanation of MOV TOL wiring, jumpers, and representative images of MOV MCC cubicle components for reference.

The issue causing the failure observed in 2014 associated with the MOV limit switch was corrected with replacement of the EFHV0092 actuator and installation of Loctite to prevent loosening of the limit switch. The TOL jumper is installed per WCNOC's licensing basis as defined in Section 8.3.3.1.2 of the WCGS SER, NUREG-0881, Supplement No. 5.

3.4 WCNOC Response to NCV 05000482/2024003-01.

The following reproduces each section of the NCV, followed by WCNOC responses.

3.4.1 NCV Section 1 3.4.1.1 From the NCV:

Failure to Remove Motor-Operated Valve Thermal Overload Bypass Jumpers during Surveillance Testing and System Maintenance Cornerstone:

Mitigating Systems Significance:

Green NCV 05000482/2024003-01 Open/Closed Cross-Cutting Aspect:

None (NPP)

Report Section:

71111.12 The inspectors identified a Green finding and associated non-cited violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, for the licensees failure to assure the applicable design requirements associated with the licensees commitment to Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves, revision 1, was correctly translated into procedures and instructions. Specifically, the licensee failed to translate that the thermal overloads be placed in force during stroking of safety-related motor-operated valves for surveillance testing and routine maintenance into procedures and instructions.

3.4.1.2 WCNOC Response:

In March of 1977, the NRC published RG 1.106 R1, Thermal Overload Protection for Electric Motors on Motor-Operated Valves. The regulatory guide was published to describe a method acceptable to the NRC staff for complying with 10 CFR 50 Appendix A and Appendix B criteria regarding the application of thermal overload protection devices used with MOVs. The methods provided in the RG 1.106 Rev 1 would ensure that the thermal overload protection devices would not needlessly prevent an MOV from performing its safety-related function.

In order to ensure a thermal overload (TOL) did not hinder the safety function of MOVs, the NRC described three acceptable methods in RG 1.106 Rev 1 as regulatory position 1(a), 1(b), or 2. Of these three positions, WCNOC chose regulatory position 1(a), which is repeated in Figure 3.4A below.

to 000729 Page 16 of 28 Figure 3.4A: Position 1(a) highlighted from RG 1.106 Rev 1.

For clarity, although not used at WCNOC, 1(b) describes an automatic bypass method which leaves thermal overloads in force (active in the circuit) normally and automatically bypasses them with an active control logic (for example with relays) during an accident condition.

With the 1(a) option, which is used at WCGS, one very important word contained in the statement is the word only.

The thermal overload protection devices should be continuously bypassed and temporarily placed in force only when the valve motors are undergoing periodic or maintenance testing.

Figure 3.4B: Position 1(a) highlighted to point out its use of only vs must.

This is a key concept since it does not say they must be placed in force when the valve motors are undergoing periodic or maintenance testing as misinterpreted by the violation.

As noted in both RG 1.106 Rev 1 and in Section 8.3.3.1.2 of the WCGS SER Supplement 5, the NRC was concerned with thermal overloads preventing an MOV from performing its safety related function. As noted in the SER, prior to approval of WCNOCs operating license, this led to WCNOC installing permanent bypass jumpers as a passive method to bypass the TOLs. The NRC agreed with this method and resolved their concern with the TOL as shown in Figure 3.4C.

to 000729 Page 17 of 28 Figure 3.4C: Paragraph 1 from 8.3.3.1.2 of SER Supplement 5 (February 1985)

Going back to the word only in the RG 1.106 Rev 1 position 1(a), while having a preference for the use of TOLs, the NRC did not require WCNOC to use them during normal operation or maintenance testing as shown in Figure 3.4D. The last sentence clearly states This is only a staff observation, and it is not considered an open or confirmatory item.

Figure 3.4D: Paragraph 2 from 8.3.3.1.2 of SER Supplement 5 (February 1985)

Based on the use of the word only in RG 1.106 and WCGSs SER, it is up to the discretion of the utility to decide when it is appropriate to have TOLs in force during testing and maintenance activities.

There has been no regulatory requirement or process utilized (no rule making, no generic letters, etc.) that would require WCNOC to revise its original licensing basis which currently requires jumpers to be installed for bypassing TOLs in MOVs.

3.4.2 NCV Section 2 3.4.2.1 From the NCV:

==

Description:==

The inspectors reviewed Condition Report 10023559, the licensing and design basis for safety-related motor-operated valves, and operating experience search of the licensees motor-operated valve program. The inspectors identified the following:

• Condition Report 10023559 referenced operating experience with train B essential service water travel screen wash motor-operated valve, EFHV0092 (1/2 horsepower or less motor-operated valve), that occurred on March 29, 2014, during the performance of surveillance Procedure STS KJ-001B, Integrated Diesel Generator and Safeguards Actuation Test -

to 000729 Page 18 of 28 Train B, documented in Condition Report 81790. Specifically, operators identified the 480 volt motor control center breaker cubicle, for valve EFHV0092, was smoking heavily. In response to the smoke, the operators opened the breaker for valve EFHV0092 and the smoke began to dissipate. The operators found valve EFHV0092 actuator was hot to the touch due to a locked rotor overthrust condition 3.4.2.2 WCNOC Response:

It is important to note with this historical event from 10 years ago that a limit switch failed which caused the valve to not shut off after opening and achieving its safety related position. The valve completed its safety function as design by RG 1.106 Rev 1. Inspection of the cubicle identified the thermal overloads overheated, as would be expected. Smoke generated from the overload heating inside the breaker cubicle for this specific valve; smoke was not generated from components outside of the breaker cubicle within the MCC in the ESW pumphouse. No fire occurred. Corrective work replaced the thermal overloads along with lugs connected to the TOL.

No other components inside the cubicle required replacement. The MOV limit switch failed first, which led to the condition responsible for the TOL overheating. The TOL functioned as designed by allowing the valve to fulfill its safety function per the WCNOC licensing basis established by the SER Section 8.3.3.1.2 (NUREG 0881 Supplement No. 5).

3.4.3 NCV Section 3 3.4.3.1 From the NCV:

The operator actions were required to remove power from valve EFHV0092 because the thermal overloads were not placed in force during surveillance testing in accordance with the design as specified in the Updated Safety Analysis Report (USAR), section 8.3.1.1.2.e, and appendix 3A, which states, in part, all starters for motor-operated valves are equipped with thermal overload relays.

3.4.3.2 WCNOC Response:

Operator actions were required due to failure of the limit switch in the MOV. The TOL were jumpered per the WCNOC licensing basis as noted in Section 8.3.3.1.2 of the WCNOC SER contained in NUREG-0881 Supplement No. 5.

The WCNOC Updated Safety Analysis Report (USAR) section 8.3.1.1.2.e has a specific statement on thermal overloads for MOVs repeated in Figure 3.4F.

Figure 3.4F: Paragraph on MOVs from USAR Section 8.3.1.1.2.e.

This USAR wording agrees with the WCNOC licensing basis in NUREG-0881 Supplement 5 and with the original interpretation of RG 1.106 Rev 1 with the word only in position 1(a).

to 000729 Page 19 of 28 This wording was changed based on a violation WCNOC received in 2013 from a Component Design Basis Inspection (CDBI). The change does not change the WCNOC licensing basis established in NUREG-0881 Supplement 5 SER.

3.4.4 NCV Section 4 3.4.4.1 From the NCV:

• The thermal overload relay trip contacts located in 480 volt motor control centers for all safety-related valves, are bypassed in accordance with Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves, revision 1, dated March 1977. Regulatory Guide 1.106, revision 1, position 1 states, in part, provided that the completion of the safety function is not jeopardized or that other safety systems are not degraded, (a) the thermal overload protection devices should be continuously bypassed and temporarily placed in force only when the valve motors are undergoing periodic or maintenance testing.

3.4.4.2 WCNOC Response:

WCNOC agrees with the statement. Exact wording from RG 1.106 R1 Position 1(a) is repeated below. As noted previously, the wording uses only and not must in this statement.

Figure 3.4G: Position 1(a) highlighted to point out its use of only vs must.

3.4.5 NCV Section 5 3.4.5.1 From the NCV:

• The NRC defines maintenance, in accordance with Regulatory Guide 1.160, Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, revision 4, as follows:

As discussed in the Federal Register (FR) notice, Final Commission Policy Statement on Maintenance at Nuclear Power Plants, dated March 23, 1988 (Ref. 5),

maintenance is defined as the aggregate of those functions required to preserve or restore safety, reliability, and availability of plant SSCs. Maintenance includes not only activities traditionally associated with identifying and correcting actual or potential degraded conditions (i.e., repair, surveillance, diagnostic examination, and preventive measures), but extends to all supporting functions for the conduct of these activities. The activities and supporting functions that are included in the definition of Maintenance are listed in the policy statement.

to 000729 Page 20 of 28 3.4.5.2 WCNOC Response:

As detailed thoroughly in Section 3.2.2, the attempt by the NRC to reinterpret the wording in a regulatory guide that our station committed to during initial plant licensing, using definitions from a regulatory guide developed years after the issuance of our SER and operating license, is fundamentally flawed and unjustifiable. The regulatory framework established at the time of our plant's licensing should remain consistent and stable. Introducing definitions from a later-developed regulatory guide undermines the regulatory certainty that licensees rely upon for compliance and operational planning.

Our station's commitments were made based on the regulatory guides and definitions in effect at the time of licensing. These commitments were reviewed and approved by the NRC, forming the basis of our SER and operating license. Reinterpreting these commitments using later definitions violates the principle of regulatory finality. The NRC's own procedures and legal precedents support the notion that changes to regulatory interpretations should not be applied retroactively to previously issued licenses unless explicitly stated. Applying new definitions retroactively without proper rulemaking or license amendment processes is procedurally improper.

3.4.6 NCV Section 6 3.4.6.1 From the NCV:

Regulatory Guide 1.106 also states, in part, where the thermal overload protection devices are bypassed, it is important to ensure that the bypassing does not result in jeopardizing the completion of the safety function or in degrading other safety systems because of any sustained abnormal motor circuit currents that may be present. As an example, for small motors (1/2 horsepower or less), the magnetic trip devices provided in the motor combination starter breaker may not adequately protect the circuit at all times against sustained locked rotor currents. This was the condition described in Condition Report 81790 when EFHV0092 was at sustained locked rotor currents causing damage to the motor and impacting the safety-related 480 volt motor control center (i.e., smoke emitting from the motor control center).

3.4.6.2 WCNOC Response:

Per required design and SER Section 8.3.3.1.2, the thermal overload control circuit was jumpered preventing the thermal overload from opening with the locked rotor current. The condition did not result in degrading other safety systems as evident by the troubleshoot work orders only replacing the thermal overload relay related components within the MCC cubicle. A picture of the 480 VAC MCC containing the breaker cubical for EFHV0092 is provided in Attachment 4 of this letter. The picture of the MCC shows no signs of damage of the areas surrounding the breaker cubicle.

As documented in the associated work orders 14-385283-000 and 14-385283-000, components replaced inside the cubicle were limited to the thermal overload relay, which would be expected to generate heat with the control circuit jumpered.

The locked rotor current was caused by a limit switch malfunction within the MOV after the valve reached is safety-related position. The switch malfunction was the initial failure. Had the switch not failed, the locked rotor condition would have not occurred. Corrective action taken following the event repaired the MOV limit switch, correcting the condition.

to 000729 Page 21 of 28 It is also important to note this condition occurred during Safeguards Actuation Testing, which is initiated by inserting the Safety Injection Signal. For the same test, the condition observed would have also occurred at any station designed to employ the alternate automatic bypass function allowed by RG 1.106 R1, Position 1(b). For 1(b) plants, the actuation signal in Safeguards Actuation Testing automatically bypasses the TOLs, which would result in the same TOL overheating condition in the event of a limit switch malfunction within an MOV. This interpretation would imply that even those plants would need to hang numerous clearance orders to lift wires and test in a non-safeguards lineup for safeguards testing.

In this case, with the permanent jumper installed, the surveillance tests identified the condition within the MOV, allowing the station to take corrective action to ensure the MOV could perform if called upon in a postulated design basis accident.

Of note is the significant time of 10 years since the 2014 event noted in the current NCV. Due to the time lapse, a lot of the detail has been lost. A review of prior inspection reports showed this condition was also previously reviewed by the NRC in 2017. CR 81790 was listed in Integrated Inspection Report 05000482/2017004 page A1-7 (ML18043A114). Since the review took place in 2017, it was only 3 calendar years form the time of the event when more detail would have been known from station personnel and the NRC. The inspection reports from that time period did not elaborate on the condition having any additional significance beyond actions which were taken to address the MOV limit switch immediately following the condition.

As an additional practical consideration to having jumpers installed, the EFHV0092 valve is located in the Essential Service Water system, which is a raw lake water system. As a raw water system, the particular MOV detailed in this historical event provides a good example of why jumpers are needed to ensure completion of a safety related function. Normal effects of raw water on piping systems can potentially cause an MOV motor to momentarily require additional torque from its standard full load current where an active thermal overload (not jumpered) could lead to the valve being disabled and prevent it from performing its safety related function.

To illustrate this, in 1993, the instantaneous breaker setting for the redundant train valve, EFHV0091 had to be increased from 7 amperes (A) to 10 A when it was determined an overly conservative breaker setting was causing the breaker to open. This is detailed in work request and engineering disposition 4940-93.

3.4.7 NCV Section 7 3.4.7.1 From the NCV:

• NRC Component Design Bases Inspection Report 0500482/2013008 documented non-cited violation (NCV) 2013008-10, Failure to Provide Procedure Instructions to Remove Thermal Overload Bypass Jumpers, for the licensees failure to translate the requirements into motor-operated valve diagnostics testing Procedure MGE LT-099, MOV Diagnostic Testing. Also, the Wolf Creek USAR, section 8.3.1.1.2, had incomplete information which does not support Regulatory Guide 1.106, revision 1. The licensee entered this deficiency into their corrective action program as Condition Reports 73120 and 73421. The licensees corrective actions were to (1) update USAR, section 8.3.1.1.2, to reflect the requirements of Regulatory Guide 1.106 Thermal Overload Protection for Electric Motors on Motor-Operated Valves, by failing to translate into maintenance and surveillance procedures and instructions, the regulatory guide position to place thermal overloads in force during stroking of safety-related motor-operated valves.

to 000729 Page 22 of 28 (USAR change request 2013-049) and (2) update the diagnostic testing procedure for motor-operated valves to remove the thermal overload bypass jumpers. The licensee revised Procedure MGE LT-100, Limitorque Valve Operator General Notes and Details, to include thermal overload protection requirements that the thermal overload protection device be continuously bypassed and temporarily placed in force when the valve motors undergo periodic or maintenance testing. Procedure MGE LT-100, revision 13, step 7.3.11, states in part, Regulatory Guide 1.106, revision 1 requires thermal overload protection devices be continuously bypassed and temporarily placed in force when the valve motors are undergoing periodic, or maintenance, testing. Maintenance testing was defined as the performance of activities associated with maintenance procedures, and/or work instructions that remove limit switch compartment cover on safety-related motor-operated valves with thermal overload bypass jumpers. However, this is contrary to Regulatory Guide 1.160; NRC, Final Commission Policy Statement on Maintenance of Nuclear Power Plants, Federal Register, Volume 53, Number 56, pp. 9430-9431 (53 FR 9430) March 23, 1998; and licensee Procedure AP 23M-001, WCGS Maintenance Rule Program, revision 14, step 4.15.

3.4.7.2 WCNOC Response:

The discussion on maintenance versus surveillance testing does not apply since WCNOCs licensing basis allows the jumpers to be installed during all conditions per NUREG-0881 Supplement 5 SER for WCGS. See Figure 3.4H below. Any other interpretation is applying backfit without going through the 10 CFR 50.109 back fitting regulatory process.

Figure 3.4H: Paragraph 2 from 8.3.3.1.2 of SER Supplement 5 (February 1985) 3.4.8 NCV Section 8 3.4.8.1 From the NCV:

From the above, the inspectors concluded that the licensee corrected the performance deficiency associated with NCV 2013008-10, Failure to Provide Procedure Instructions to Remove Thermal Overload Bypass Jumpers, for the licensees failure to translate the requirements into motor-operated valve diagnostics testing Procedure MGE LT-099, MOV Diagnostic Testing. However, the licensee failed to translate the applicable design requirements associated with the licensees commitment to Regulatory Guide 1.106, revision 1, position 1, for safety-related motor-operated valves were correctly translated into specifications, drawings, procedure, and instructions.

Specifically, as part of their extent of condition review, the licensee failed to translate the position to 000729 Page 23 of 28 that the thermal overloads be placed in force (bypass jumpers removed) during stroking of safety-related motor-operated valves for periodic or maintenance testing into procedures and instructions, which included surveillance and all types of maintenance testing.

3.4.8.2 WCNOC Response:

RG 1.106 R1 Position 1(a) does not state overloads must be placed in force. It only requires the TOL to be bypassed to ensure completion of the safety related function of the MOV. It only allows the TOL to be in force during maintenance activities. With WCNOCs installation this means the TOLs must be continuously jumpered to ensure the safety related function of the MOV and can only be removed during periodic or maintenance testing. It does not require them to be removed.

Figure 3.4I: Position 1(a) highlighted to emphasize its use of only versus must This is supported by NUREG-0881 Supplement 5 SER for WCGS shown in Figure 3.4J.

Figure 3.4J: Paragraph 2 from 8.3.3.1.2 of SER Supplement 5 (February 1985) 3.4.9 NCV Section 9 3.4.9.1 From the NCV:

In response to the inspectors conclusions, the licensee asserted the proposed NCV was a backfit.

Specifically, the licensee was committed and approved to Regulatory Guide 1.106, revision 1; however, in the Safety Evaluation Report (SER) for Wolf Creek, NUREG-0881, supplement 5, issued in March 1985, acknowledged the licensees statement that thermal overloads on class 1E motor-operated valves will be permanently bypassed with no discussion of removal during to 000729 Page 24 of 28 surveillance testing. The licensee thus claimed the agency had approved the use of permanently bypassed thermal overload during the application process. The inspectors determined the wording in the SER stated that the use of thermal overloads (i.e., removing the bypass jumpers) during testing was a prudent operational practice as a staff observation, nonetheless, the inspectors entered the backfit process and engaged backfit community of best practices to review the above referenced documents to determine if the backfit claim was valid.

3.4.9.2 WCNOC Response:

The NRC made an observation in the SER that it would be prudent to enable thermal overload protection during testing to protect the MOV motors. As shown below in Figure 3.4K, the NRC clearly stated that this is only a staff observation, and it is not considered an open or confirmatory item. Thus, NRC did not intend to require enabling TOL protection during testing. While WCNOC agreed with enabling TOL protection in the 2013 violation response for testing performed after intrusive valve maintenance, WCNOC does not agree that enabling TOL protection for periodic surveillance testing and operability testing is either required or prudent.

Figure 3.4K: Paragraph 2 from 8.3.3.1.2 of SER Supplement 5 (February 1985) 3.4.10 NCV Section 10 3.4.10.1 From the NCV:

From the review of the above documents, the backfit community of best practices concluded the USAR did not contain all the appropriate information associated with the requirements of Regulatory Guide 1.106, revision 1, which includes regulatory position 1(a) and concluded the proposed NCV was not a backfit. Lastly, the licensee stated they would contest the NCV based on their definition of maintenance testing contained in Procedure MGE LT-100.

3.4.10.2 WCNOC Response:

It is unclear to WCNOC what information was reviewed as part of the backfit community of best practices review, as WCNOC was not consulted. WCNOC provided a white paper to the WCGS SRI in approximately June 2024 in response to the proposed violation. This white paper outlined WCNOCs position and sought to use the Very Low Safety Significance Issue Resolution (VLSSIR) process to resolve the disagreement in the interpretation of the plants licensing basis.

The issue of concern was (and remains) only related to TOL status during testing, and not TOL status while SSCs are in their safety function lineup. The white paper indicated that the to 000729 Page 25 of 28 reinterpreted position suggested by the NRC would ultimately lead to backfitting the plant and result in no improvement to safety, while increasing overall risk to the station. WCNOC was informed later by the WCGS SRI that this white paper was provided the NRC Region IV and was being reviewed by a backfit committee.

In approximately July 2024, the NRC SRI informed WCNOC that the Region IV backfit committee had concluded that this reinterpretation would be considered backfit. No formal documentation was provided to WCNOC. WCNOC considered the issue closed at that time. Later, approximately in August 2024, the WCGS SRI informed WCNOC that the Region IV backfit committee had retracted their backfit position following further discussion with the SRI and further review.3 WCNOC informed the NRC that it remained in disagreement with the reinterpretation and that it would be forced to contest the violation if levied. At no point did WCNOC state that it would contest the NCV on the grounds of the definition of maintenance testing contained in Procedure MGE LT-100, as detailed in the NCV. WCNOC informed the NRC that it would be forced to contest the violation due to it inappropriately reinterpreting our approved licensing basis and WCNOC would be unable to comply with this reinterpretation, for the reasons detailed in this letter. WCNOC would be forced to assume additional and unnecessary nuclear safety risk or potentially adopt a new RG 1.106 position if it could not identify a way to comply with the new interpretation. WCNOC was unable to review the proposed language of the NCV until the final inspection report was transmitted, dated November 1, 2024.

By reinterpreting the WCGS licensing basis application of RG 1.106 R1, the recent violation is imposing backfit on the station without going through the appropriate 10 CFR 50.109 back fitting regulatory process.

3Note that this issue was discussed initially with the NRC Region IV on March 4, 2024. WCNOC presented to the NRC, Wolf Creek and NRC meeting - Questions EFHV0092 Motor Starter NG06E DF2 Breaker Cubicle Event - March 2014 (MC20 Planned Maintenance Outage). This meeting was in response to a proposed violation by the NRC SRI with similar, but different, wording to this final NCV. WCNOC believed that the concern was resolved following this presentation.

4 Backfit Analysis Consideration 4.1 WCNOC Backfit Analysis Request WCNOC contends that the NRC has reinterpreted RG 1.106 R1, Position 1(a), and the approved WCGS licensing basis in a manner inconsistent with original commitments. The NCV cites a violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, for not ensuring that thermal overloads are placed in force during the stroking of safety-related MOVs for surveillance testing and routine maintenance. WCNOC asserts that this interpretation is a deviation from our established licensing basis and commitments and represents a change in NRC Staff position.

RG 1.106 R1, provides guidance on thermal overload protection for electric motors on MOVs.

Position 1(a) outlines acceptable methods for ensuring that thermal overload protection devices do not prevent the motor from performing its safety-related function. WCNOC has consistently interpreted this guidance to mean that thermal overload bypass jumpers are not required to be removed for all surveillance and post maintenance operability testing. Our procedures and instructions have been developed in accordance with this interpretation, which has been previously accepted by the NRC. The staff position in the NCV represents a significant expansion of the regulatory requirements associated with RG 1.106 R1, Position 1(a).

to 000729 Page 26 of 28 WCNOCs licensing basis, as documented in our Updated Safety Analysis Report (USAR) and other licensing documents, does not include a commitment to remove thermal overload bypass jumpers for all surveillance and post-maintenance operability testing of safety-related MOVs. The NRCs current interpretation represents a new or different regulatory position, which constitutes a backfit under 10 CFR 50.109(a)(1).

The NRC has not provided a backfit analysis as required by 10 CFR 50.109(a)(2) to justify this new interpretation. A backfit analysis must demonstrate that the new requirement provides a substantial increase in the overall protection of public health and safety and that the direct and indirect costs of implementation are justified as outlined in 10 CFR 50.109(a)(3). WCNOC requests that the NRC conduct a thorough backfit analysis to evaluate the necessity and impact of this new interpretation.

4.1.1 Risk Impacts Wolf Creek Nuclear Operating Corporation (WCNOC) firmly believes that attempting to comply with the new interpretation in the NCV will increase the overall nuclear safety risk at our station and will thus increase risk to public health and safety. Removing thermal overload (TOL) jumpers for every surveillance imposes significantly more risk and out-of-service time than the potential for motor damage with TOLs bypassed during surveillance testing. Stroking MOVs for surveillance testing, where no corrective or preventative maintenance has been performed on the valve or motor, presents a very low risk to the valve or valve motor. WNCOC also employs periodic VOTES testing as part of our MOV program for early identification of any degrading MOV conditions.

The added risk of removing and replacing jumpers inside the breaker cubicle for MOVs each time a surveillance is performed is unwarranted, especially when the motor damage risk is low. Testing with the jumpers in their safety related configuration ensures that MOVs can perform their safety function of stroking as required during an accident. This is true for both periodic surveillance testing as well as post-maintenance operability testing. Additionally, it reduces the potential for human error when jumpers are removed and reinstalled, which could result in incorrect placement, stripped screws, or broken lugs due to repeated loosening and tightening of connections. While WCNOC maintains an incredibly safe clearance order process, this reinterpretation and the resulting numerous clearance order evolutions would also unnecessarily increase safety risk to our maintenance personnel, with no benefit to nuclear safety.

Testing an MOV is not intrusive and does not put the valve at a higher risk of stalling than stroking during normal operation. Control Room hand switches or actuation circuitry are used to reposition valves for both normal operation and surveillance and post-maintenance operability testing.

Safety related valves are routinely repositioned as needed for normal operation, such as for swapping trains and for maintenance personnel protection (clearance orders). There are no requirements for removing thermal overload bypass jumpers for normal operation or for maintenance workmans protection needs.

Employing TOLs during testing is also unlikely to prevent mechanical damage to the MOV if the valve malfunctions. As stated in RG 1.106 R1, thermal overload relays are designed primarily to protect continuous-duty motors while running, rather than during starting. These overload devices are unlikely to protect intermittent-duty motors or valve components during the short-duration valve strokes performed in surveillance testing. If a limit or torque switch is not operating properly, the TOL is unlikely to act quickly enough from the cumulative effect of heating to prevent mechanical valve or gearbox damage. This has been confirmed in practice.

to 000729 Page 27 of 28 If thermal overload jumpers are removed for surveillance stroke tests, a subsequent stroke test may be required to ensure that the jumper is landed appropriately and does not inhibit valve movement, consistent with the practice of requiring testing after a wiring modification. With the new interpretation in the NCV, it is not possible to leave the jumper installed per design for this stroke test, because it would be considered periodic or maintenance testing. There is an inherent risk in removing and reinstalling thermal overload jumpers without subsequent testing, as they may not be reinstalled properly. This would introduce a new risk that the TOLs prevent the valves from moving to fulfill a safety function. Removing thermal overload bypass jumpers for surveillance stroke tests, during which motor damage is unlikely, thus carries more risk in failing to ensure that the valves can perform their safety function of stroking as required during an accident.

Keeping the thermal overload protection devices bypassed during surveillance testing does not change the frequency of an initiating accident because the failure of a single safety-related MOV is not, by itself, an initiator of any previously evaluated design basis accident. Valves are active components that either position to "open" or "close" as required to fulfill safety functions. As such, safety-related MOVs are subject to single active failures, but such failures are not accident initiators. Accordingly, bypassing TOL devices during MOV surveillance testing does not require changes to assumptions regarding MOV availability, single-failure protection, or the associated systems' capabilities for performing accident mitigation functions.

WCNOCs adoption of RG 1.106 R1, Position 1(a), ensures the valves are in the desired configuration to perform their safety functions during a Design Basis Accident (DBA). The NRCs challenge to the installation of the jumpers during testing has no bearing on the jumper installation for a given valve when called upon to perform its safety function during a DBA. This challenge only pertains to jumper configuration during testing activities. There is no question that Position 1(a) of RG 1.106 R1 intended for the jumpers to be installed when required to respond to a DBA.

In contrast, attempting to comply with this interpretation would lead to significantly increased unavailability time for safety-related components, as additional clearance orders and field work would be required. Unnecessarily removing a safety train from service to perform routine testing significantly increases the core damage frequency (CDF) and large early release frequency (LERF) of the station. Performing post-maintenance operability testing not in design configuration would likewise increase plant and public safety risk.

4.1.2 Cost Impacts Compliance with the NRC's interpretation requiring the removal of thermal overload bypass jumpers for all surveillance and post-maintenance operability testing of safety-related motor-operated valves (MOVs) will impose significant costs on Wolf Creek Nuclear Operating Corporation. A non-exhaustive search yielded approximately 134 safety-related MOVs with TOLs installed, each with required surveillances and periodic maintenance requirements. Two new clearance orders would have to be developed and implemented for every MOV surveillance and each post-maintenance operability test performed at WCGS.4 These costs include the development and implementation of clearance orders, which necessitate preparation, independent reviews, planning, and numerous component manipulations.

Additionally, substantial additional field work would be required to place and remove clearance orders, as well as to remove and re-install the thermal overload bypass jumpers. This process would also involve extensive briefings for operators and electrical maintenance teams to ensure proper understanding and execution of the clearance orders and component manipulations.

Furthermore, the introduction of this new work during plant outages may extend the duration of to 000729 Page 28 of 28 outages, leading to increased operational costs. Overall, these requirements represent a considerable financial and operational burden on the station, with no identified improvement to nuclear safety.

Among the other options available to WCNOC to comply with this interpretation, WCNOC could be forced to adopt Position 2 of RG 1.106 R1 if no clear method to safely implement the new interpretation of Position 1(a) is identified. Adopting Position 2 of RG 1.106 R1 would impose substantial costs on WCNOC. This position requires significant changes, including the development of a new program to ensure compliance with the updated thermal overload protection requirements. Additionally, WCNOC would need to revise the TS, which would involve extensive documentation updates, regulatory reviews, and a License Amendment Request.

Implementing Position 2 would necessitate a major design modification to our existing systems.

This modification would include engineering design work, potential procurement of new TOL components, and installation activities. Each of these steps involves considerable planning, coordination, and execution efforts, leading to increased operational costs and potential downtime. Overall, the adoption of Position 2 would represent a significant financial and operational burden on the station, with an overall increase in risk to the station, as the TOLs would then be at risk of preventing the MOVs from performing their nuclear safety function.

4This hypothetical does not consider the previously stated innate problem with entering a circular loop upon removing the equipment from service for intrusive maintenance, with no clear ability to complete post-maintenance operability testing with this new interpretation. It is intended to illustrate the cost impacts of attempting to comply with the NCV.

5 WCNOC Conclusion WCNOC respectfully requests that the NRC reconsider the issuance of NCV 05000482/2024003-01 based on the arguments presented above. WCNOC believes that current practices are consistent with the WCGS approved licensing basis and RG 1.106 R1. WCNOC seeks a resolution that acknowledges our compliance with the established regulatory framework and avoids unnecessary and unjustified burdens on our operations.

WCNOC contends that the NRC has reinterpreted RG 1.106 R1, Position 1(a), and the approved WCGS licensing basis in a manner inconsistent with original commitments. If the NRC upholds this reinterpretation and determines that a Performance Deficiency exists, WCNOC requests that the NRC conduct a thorough backfit analysis to evaluate the necessity and impact of this new interpretation, as required by 10 CFR 50.109(a)(2).

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Copy of Non-Cited Violation from Wolf Creek Generating Station - Integrated Inspection Report 05000482/2024003 4 Pages to 000729 Page 1 of 4 Copy of Non-Cited Violation from Wolf Creek Generating Station - Integrated Inspection Report 05000482/2024003 Failure to Remove Motor-Operated Valve Thermal Overload Bypass Jumpers during Surveillance Testing and System Maintenance Cornerstone:

Mitigating Systems Significance:

Green NCV 05000482/2024003-01 Open/Closed Cross-Cutting Aspect:

None (NPP)

Report Section:

71111.12 The inspectors identified a Green finding and associated non-cited violation of 10 CFR Part 50, Appendix B, Criterion III, Design Control, for the licensees failure to assure the applicable design requirements associated with the licensees commitment to Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves, revision 1, was correctly translated into procedures and instructions. Specifically, the licensee failed to translate that the thermal overloads be placed in force during stroking of safety-related motor-operated valves for surveillance testing and routine maintenance into procedures and instructions.

==

Description:==

The inspectors reviewed Condition Report 10023559, the licensing and design basis for safety-related motor-operated valves, and operating experience search of the licensees motor-operated valve program. The inspectors identified the following:

• Condition Report 10023559 referenced operating experience with train B essential service water travel screen wash motor-operated valve, EFHV0092 (1/2 horsepower or less motor-operated valve), that occurred on March 29, 2014, during the performance of surveillance Procedure STS KJ-001B, Integrated Diesel Generator and Safeguards Actuation Test -

Train B, documented in Condition Report 81790. Specifically, operators identified the 480 volt motor control center breaker cubicle, for valve EFHV0092, was smoking heavily. In response to the smoke, the operators opened the breaker for valve EFHV0092 and the smoke began to dissipate. The operators found valve EFHV0092 actuator was hot to the touch due to a locked rotor overthrust condition. The operator actions were required to remove power from valve EFHV0092 because the thermal overloads were not placed in force during surveillance testing in accordance with the design as specified in the Updated Safety Analysis Report (USAR), section 8.3.1.1.2.e, and appendix 3A, which states, in part, all starters for motor-operated valves are equipped with thermal overload relays. The thermal overload relay trip contacts located in 480 volt motor control centers for all safety-related valves, are bypassed in accordance with Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves, revision 1, dated March 1977. Regulatory Guide 1.106, revision 1, position 1 states, in part, provided that the completion of the safety function is not jeopardized or that other safety systems are not degraded, (a) the thermal overload protection devices should be continuously bypassed and temporarily placed in force only when the valve motors are undergoing periodic or maintenance testing. The NRC defines maintenance, in accordance with Regulatory Guide 1.160, Monitoring the Effectiveness of Maintenance at Nuclear Power Plants, revision 4, as follows:

As discussed in the Federal Register (FR) notice, Final Commission Policy Statement on Maintenance at Nuclear Power Plants, dated March 23, 1988 (Ref. 5),

maintenance is defined as the aggregate of those functions required to preserve or restore safety, reliability, and availability of plant SSCs. Maintenance includes not only activities traditionally associated with identifying and correcting actual or to 000729 Page 2 of 4 potential degraded conditions (i.e., repair, surveillance, diagnostic examination, and preventive measures), but extends to all supporting functions for the conduct of these activities. The activities and supporting functions that are included in the definition of Maintenance are listed in the policy statement.

Regulatory Guide 1.106 also states, in part, where the thermal overload protection devices are bypassed, it is important to ensure that the bypassing does not result in jeopardizing the completion of the safety function or in degrading other safety systems because of any sustained abnormal motor circuit currents that may be present. As an example, for small motors (1/2 horsepower or less), the magnetic trip devices provided in the motor combination starter breaker may not adequately protect the circuit at all times against sustained locked rotor currents. This was the condition described in Condition Report 81790 when EFHV0092 was at sustained locked rotor currents causing damage to the motor and impacting the safety-related 480 volt motor control center (i.e., smoke emitting from the motor control center).

• NRC Component Design Bases Inspection Report 0500482/2013008 documented non-cited violation (NCV) 2013008-10, Failure to Provide Procedure Instructions to Remove Thermal Overload Bypass Jumpers, for the licensees failure to translate the requirements into motor-operated valve diagnostics testing Procedure MGE LT-099, MOV Diagnostic Testing. Also, the Wolf Creek USAR, section 8.3.1.1.2, had incomplete information which does not support Regulatory Guide 1.106, revision 1. The licensee entered this deficiency into their corrective action program as Condition Reports 73120 and 73421. The licensees corrective actions were to (1) update USAR, section 8.3.1.1.2, to reflect the requirements of Regulatory Guide 1.106 Thermal Overload Protection for Electric Motors on Motor-Operated Valves, by failing to translate into maintenance and surveillance procedures and instructions, the regulatory guide position to place thermal overloads in force during stroking of safety-related motor-operated valves.

(USAR change request 2013-049) and (2) update the diagnostic testing procedure for motor-operated valves to remove the thermal overload bypass jumpers. The licensee revised Procedure MGE LT-100, Limitorque Valve Operator General Notes and Details, to include thermal overload protection requirements that the thermal overload protection device be continuously bypassed and temporarily placed in force when the valve motors undergo periodic or maintenance testing. Procedure MGE LT-100, revision 13, step 7.3.11, states in part, Regulatory Guide 1.106, revision 1 requires thermal overload protection devices be continuously bypassed and temporarily placed in force when the valve motors are undergoing periodic, or maintenance, testing. Maintenance testing was defined as the performance of activities associated with maintenance procedures, and/or work instructions that remove limit switch compartment cover on safety-related motor-operated valves with thermal overload bypass jumpers. However, this is contrary to Regulatory Guide 1.160; NRC, Final Commission Policy Statement on Maintenance of Nuclear Power Plants, Federal Register, Volume 53, Number 56, pp. 9430-9431 (53 FR 9430) March 23, 1998; and licensee Procedure AP 23M-001, WCGS Maintenance Rule Program, revision 14, step 4.15.

From the above, the inspectors concluded that the licensee corrected the performance deficiency associated with NCV 2013008-10, Failure to Provide Procedure Instructions to Remove Thermal Overload Bypass Jumpers, for the licensees failure to translate the requirements into motor-operated valve diagnostics testing Procedure MGE LT-099, MOV Diagnostic Testing. However, the licensee failed to translate the applicable design requirements associated with the licensees commitment to Regulatory Guide 1.106, revision 1, position 1, for safety-related motor-operated to 000729 Page 3 of 4 valves were correctly translated into specifications, drawings, procedure, and instructions.

Specifically, as part of their extent of condition review, the licensee failed to translate the position that the thermal overloads be placed in force (bypass jumpers removed) during stroking of safety-related motor-operated valves for periodic or maintenance testing into procedures and instructions, which included surveillance and all types of maintenance testing.

In response to the inspectors conclusions, the licensee asserted the proposed NCV was a backfit.

Specifically, the licensee was committed and approved to Regulatory Guide 1.106, revision 1; however, in the Safety Evaluation Report (SER) for Wolf Creek, NUREG-0881, supplement 5, issued in March 1985, acknowledged the licensees statement that thermal overloads on class 1E motor-operated valves will be permanently bypassed with no discussion of removal during surveillance testing. The licensee thus claimed the agency had approved the use of permanently bypassed thermal overload during the application process. The inspectors determined the wording in the SER stated that the use of thermal overloads (i.e., removing the bypass jumpers) during testing was a prudent operational practice as a staff observation, nonetheless, the inspectors entered the backfit process and engaged backfit community of best practices to review the above referenced documents to determine if the backfit claim was valid. From the review of the above documents, the backfit community of best practices concluded the USAR did not contain all the appropriate information associated with the requirements of Regulatory Guide 1.106, revision 1, which includes regulatory position 1(a) and concluded the proposed NCV was not a backfit. Lastly, the licensee stated they would contest the NCV based on their definition of maintenance testing contained in Procedure MGE LT-100.

Corrective Actions: Condition Reports 10028066 and 10037302 Corrective Action

References:

The licensee plans to contest the NCV based on their definition of maintenance testing contained in Procedure MGE LT-100.

Performance Assessment:

Performance Deficiency: The licensees failure to place the thermal overloads in force during stroking of motor-operated valves for surveillance testing and routine maintenance was a performance deficiency.

Screening: The inspectors determined the performance deficiency was more than minor because it was associated with the Configuration Control attribute of the Mitigating Systems cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to initiating events to prevent undesirable consequences.

Specifically, the failure to place the thermal overloads in force during surveillance testing resulted in the 480 volt motor control center for EFHV0092 to heavily smoke when the motor-operated valve went to a locked rotor condition due to a limit switch failure in June 2014.

Significance: The inspectors assessed the significance of the finding using IMC 0609 Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding was determined to be of very low safety significance (Green) because it (1) was not a deficiency affecting design or qualification of a mitigating system, (2) does not represent a loss of the probability risk analysis (PRA) function of a single train technical specification system for greater than allowed outage time, (3) does not represent a loss of PRA function of one train of a multi-train technical specification for greater than its allowed outage time, (4) does not represent a loss of the PRA function of two separate technical specification systems for greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, (5) does not represent a loss of PRA system and/or function as defined by the plant risk information to 000729 Page 4 of 4 e-book or licensees PRA for greater than 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and (6) does not result in the loss of a high safety-significant, nontechnical specification train for greater than 3 days.

Cross-Cutting Aspect: Not Present Performance. No cross-cutting aspect was assigned to this finding because the inspectors determined the finding did not reflect present licensee performance. Specifically, the performance deficiency occurred in 2013 when the licensee failed to include procedures for surveillance testing and routine maintenance, such as post-maintenance testing and preventive maintenance procedures that stroke safety-related motor-operated valves other than diagnostics testing and motor-operated valve maintenance when performing the extent of condition for NCV 2013008-10, Failure to Provide Procedure Instructions to Remove Thermal Overload Bypass Jumpers.

Enforcement:

Violation: Title 10 CFR Part 50, Appendix B, Criterion III, Design Control, requires, in part, that measures shall be established to assure that applicable regulatory requirements and the design basis, as defined in 50.2 and as specified in the license application, for those structures, systems, and components to which this appendix applies are correctly translated into procedures and instructions.

Contrary to the above, from November 2013 to September 2024, the licensee failed to establish measures to assure that applicable regulatory requirements and the design basis, as defined in 50.2, and as specified in the license application assure the applicable design requirements were correctly translated into procedures and instructions. Specifically, the licensee failed to implement their design basis commitment to Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves, by failing to translate into maintenance and surveillance procedures and instructions, the regulatory guide position to place thermal overloads in force during stroking of safety-related motor-operated valves.

Enforcement Action: This violation is being treated as a non-cited violation, consistent with section 2.3.2 of the Enforcement Policy.

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Timeline of Relevant Documents 3 Pages to 000729 Page 1 of 3 Timeline of Relevant Documents

1. November 1975, NRC Issues Regulatory Guide 1.106, Thermal Overload Protection for Electric Motors on Motor-Operated Valves.

2. March 1977, NRC Issues Regulatory Guide 1.106 Rev 1, Thermal Overload Protection for Electric Motors on Motor-Operated Valves.

3. May 17, 1977, NRC Issues Construction Permit No. CPPR-147 for WCGS

4. March 1985 (Dated February 1985), NRC Issues NUREG-0881 Supplement No. 5 with 8.3.3.1.2 Thermal-Overload Protection Bypass with statement the thermal overload (TOL) relay trip contacts for all Class1E valves will be permanently bypassed with jumpers before fuel loading.

5. March 11, 1985, NRC Issues low-power Operating License NPF-32 to WCGS restricting power to 5% (ML022000385).

6. June 1985, NRC issue NUREG-0881 Supplement No. 6 (ML20127D193). No new information related to TOLs.

7. June 4, 1985, NRC Issues Facility Operating Licensing NPF-42 to WCGS, authorizing 100% thermal power operation (ML022000381).

8. June 1988, NRC publishes NUREG-1296, Thermal Overload Protection for Electric Motors on Safety-Related Motor-Operated Valves - Generic Issue II.E.6.1, with statement (emphasis added), AEOD is particularly concerned about the allowed policy of bypassing thermal overload devices during normal or accident conditions.

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9. June 28, 1989, NRC issues GL 89-10, Safety-Related Motor-Operated Valve Testing and Surveillance (Generic Letter No. 89-10) - 10 CFR 50.54(f).

10. January 6, 1993, NRC issued RG 1.160 Rev 0, Monitoring the Effectiveness of Maintenance at Nuclear Power Plants.

11. June 18, 1992, WCNOC-85 Rev 0, Motor Operated Valve Program Description.

Document was created in response to GL 89-10. The following paragraph is from WCNOC-85 Rev 0 Appendix B, page 3.

Based on the original commitment to RG 1.106 Rev 1, and the inherent inaccuracies of these devices, Wolf Creeks philosophy will remain the same in regard to thermal overload protection of safety related MOVs. Specifically, since the degree of accuracy required in this application is not realistically achievable with these devices, and there is no logical reason to provide a thermal overload device that in all probability will not trip under any circumstances, all contacts will remain bypassed except during testing.

Justification for this philosophy is provided by a comprehensive tracking and trending program to be implemented with the release of WCNOC-85. Under this program, VOTES testing will be performed at specified intervals to monitor actuator motor performance and preclude excessive motor degradation.

12. January 30, 1995, WM 95-001, Notification of completion of Actions Associated to Generic Letter 89-10, Safety-Related Motor-Operated Valve (MOV) Testing and Surveillance.

13. February 2012, NRC issued RG 1.106 Rev 2, Thermal Overload Protection for Electric Motors on Motor-Operated Valves. It notes, Current licensees may continue to use guidance the NRC found acceptable for complying with the identified regulations as long as their current licensing basis remains unchanged.

14. November 22, 2013, NRC issued Green NCV, NRC Component Design Basis Inspection (CDBI) Report 05000482/2013008 (ML13326A477).

15. December 18, 2013, CR assignment 73421-02-03 was completed in response to the NCV issued during CDBI in November of 2013. Assignment created USAR change request 2013-049 to revise USAR section 8.3.1.1.2.e. No commitment was made that jumpers will always be removed for all testing.

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16. March 29, 2014, CR 81790 initiated for smoke coming from 480VAC molded case circuit breaker MCC cubicle NG06EDF2 which contains motor starter and thermal overloads for ESW Screen wash valve MOV EFHV0092.

17. March 29, 2014, field work completed with WO 14-385283-000 Electrical Maintenance Troubleshoot to Determine Cause of Breaker NG006EDF2 Smoking while EFHV0092 was Energized. Troubleshoot removed starter contact covers with no issues found. Overload contacts overheated. Found MOV limit switch cartridge cover loose.

18. March 30, 2014, field work completed with WO 14-385283-001 NG0006EDF2 Test /

Replace breaker Existing Breaker tested satisfactory. Only components replaced in the MCC were thermal overload relays, thermal overload relay base and (2) ring terminals.

19. January 6, 2018, NRC issued RG 1.160 Rev 4, Monitoring the Effectiveness of Maintenance at Nuclear Power Plants.

20. February 12, 2018, Quarterly inspection noted CR 81790 in list of EPEs reviewed. WOLF CREEK GENERATING STATION - NRC INTEGRATED INSPECTION REPORT 05000482/2017004 (ML18043A114), page A1-7.

21. March 4, 2024, in response to SRI questions and a proposed violation, WCNOC provided SRI a white paper titled, Wolf Creek Position Document EFHV0092 Motor Starter NG06E DF2 Breaker Cubicle Event - March 2014 NRC Questions February 2024

22. March 4, 2024, WCNOC presented to NRC PowerPoint titled, Wolf Creek and NRC meeting - Questions EFHV0092 Motor Starter NG06E DF2 Breaker Cubicle Event - March 2014 (MC20 Planned Maintenance Outage) in response to proposed violation.

23. June 2024, WCNOC provided NRC SRI a white paper titled, RG 1.106 Position 1(a), TOL Protection for Electric Motors on Motor-Operated Valves in response to new proposed violation. (Language of new proposed violation different than previously proposed violation in March.) This white paper was subsequently provided to NRC Region IV by SRI.

24. Approximately July 2024, NRC SRI notified WCNOC verbally that Region IV determined the proposed violation to be backfit.

25. Approximately August 2024, NRC SRI notified WCNOC verbally that Region IV backfit determination had been retracted following further discussion with SRI.

26. November 1, 2024, NRC issued Green NCV 2024003-01 for Failure to Remove Motor-Operated Valve Thermal Overload Bypass Jumpers during Surveillance Testing and System Maintenance in Wolf Creek Generating Station - Integrated Inspection Report 05000482/2024003 (NRC ADAMS ML24295A379).

27. November 27, 2024, WCNOC documented the intent to contest the NCV in letter 000713, Notice of Intent to Contest Non-Cited Violation (NCV)05000482/2024003-01, and Request for Additional Time to Provide Wolf Creek Nuclear Operating Corporations (WCNOC) NCV Response (NRC ADAMS ML24332A126).

to 000729:

Supplemental TOL Explanatory Information 5 Pages to 000729 Page 1 of 5 Explanation of TOL Circuitry Two circuits are involved. Refer to Figure 1 of this attachment below.

Circuit 1: 480VAC Power Circuit to MOV The first circuit is a 480 VAC 3-phase electrical power circuit used to power a motor attached to a valve, commonly referred to as a motor operated valve (MOV). By nature of opening and closing the valve, the motor operates intermittently when the valve needs to be either opened or closed.

The circuit includes a circuit breaker, motor starter with contactors to open the valve, contactors to close the valve, and thermal overload relays (TOLs) all contained in the same breaker cubicle.

The contactors are controlled by 120V coils connected to the second circuit.

Circuit 2: 120VAC Control Circuit The second circuit is a lower voltage 120 VAC control circuit. This circuit is powered by a control transformer which converts 480 VAC to 120 VAC for the control circuit. The control transformer receives power from two phases of the 480 VAC power circuit (between the breaker and the motor starter). The secondary side (120 VAC) powers the control circuit. The control circuit contains contacts and switches which act as logic to control the coils on the contactors. When the coils are energized by the control circuit, they generate a magnetic force which acts to close the 3 phase power contacts inside the contactor to provide power to the 3 phase motor on the valve (MOV). Depending on which coil is energized, the valve will either open or close. An electrical interlock is provided in the control circuit by normally closed relay contacts to prevent both the open and closed coils from being energized at the same time to prevent a phase to phase electrical short.

In the 480 VAC power circuit (first circuit), the thermal overloads are connected downstream of the open and closed contactors. Only one set of overloads is used with the two contactors. These particular thermal overload relays are configured to have one for each of the 3 phases. Thus, there are 3 separate overload relays. All 3 relays have thermal heaters installed which simulate the heat developed in the motor winding for the MOV. The three relays and their corresponding heaters are installed into a relay base. The relays extend upward from the base. They are narrow in width and proportionally long in length. The three relays sit side by side together in a relay base. The three individual heaters are attached on top of the overload relay with one heater per overload relay (on set for each phase of the 3 phases going to the MOV). The heaters interact with the relay to mechanically change the state of control contacts within each overload relay.

As noted before, the current flowing through the heaters simulates the heat being generated in the motor winding of the MOV. If the valve is binding, as can happen in a raw water system such as from a cooling lake, the increased torque required to move the valve can cause more electrical current to develop in order to generate the increased torque needed to move the valve. This increased electrical current leads to more heat being generated in the motor winding and also in the overload heaters, which are simulating (not sensing) the motor winding heat. If enough heat is generated, it causes a bimetallic device to open the control circuit contacts, which will de-energize the coil in the motor contactor. With the control coil deenergized and the magnetic opening force removed, the more robust contactor contacts spring back open in all 3 phases, removing 480 VAC electrical power from the motor on the valve.

Due to the safety related use of the MOVs in nuclear power plants, the NRC in the 1970s determined the overloads could open prematurely, preventing an MOV from performing its safety related function during a postulated accident condition. RG 1.106 R0 was published in 1975 and Revision 1 was published in March of 1977, which WCGS is licensed to per NUREG-0881 Supplement 5.

to 000729 Page 2 of 5 RG 1.106 R1 favors completion of the valve safety function above protection of the component.

The NRC authors understood that there was a tradeoff between protecting the MOV if a malfunction were to occur versus ensuring the valve is able to complete its safety function in an emergency situation. This is a similar philosophy the National Electric Code (NEC) uses in cases with electric motor driven fire pumps where overloads are completely removed and not installed.

At WCGS, to offset risk with not using overloads, the MOV program connects diagnostic equipment to the MOV periodically or when intrusive maintenance is performed. During surveillance and post-maintenance operability testing, it is important for MOVs to be tested with the jumpers installed so any malfunctions will be detected during the activity. The NCV suggests removing the jumpers during surveillance testing and normal operation, which is not only contrary to the WCGS licensing basis, but also creates a new vulnerability in the circuit by not verifying the equipment performs as intended by design.

to 000729 Page 3 of 5 Figure 1: Simplified Drawing of 480V Power Circuit, 120V Control Circuit, and the Thermal Overloads for a Typical Motor Operated Valve (MOV) Breaker Cubicle to 000729 Page 4 of 5 Figure 2: Representative Motor Control Center (MCC) MOV Breaker Cubicle (Components affected by condition identified on March 29, 2014 in CR 81790 are indicated.)

Thermal Overload Relays -

(replaced)

(components replaced were in this area)

Motor Starter Contactor -

opens MOV (left installed)

Overload Control Relay (left installed)

Motor Starter Contactor -

closes MOV (left installed)

Breaker (tested satisfactory and left installed) to 000729 Page 5 of 5 Figure 3: 480VAC Motor Control Center (MCC) Breaker Cubicle for MOV EFHV0092 (No damage around cubicle from condition identified on March 29, 2014 in CR 81790.)

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Additional Context from NUREG-1296 and Regulatory Guide 1.106, Revision 2 4 Pages to 000729 Page 1 of 4 Additional Context from NUREG-1296 and Regulatory Guide 1.106, Revision 2 By reviewing historical documents related to application of thermal overloads with MOVs, it is clear there has been internal debate inside the NRC after RG 1.106 R1 was released. RG 1.106 R1 was released in March of 1977. Following issue of WCGS operating license NPF-42 in 1985, NUREG-1296, was issued by the NRC in June 1988, which provided additional information from the Office for Analysis and Evaluation of Operational Data (AEOD), in response to concerns related to RG 1.106 R1:

AEOD is particularly concerned about the allowed policy of bypassing thermal overload devices during normal or accident conditions. Regulatory Guide 1.106 favors compromising the function of thermal overload devices in favor of completing the safety-related action of valves. The purpose of this study was to determine if the guidance contained in Regulatory Guide 1.106 is appropriate and, if not, to recommend the necessary changes.

Thermal overload devices can provide useful protection for valve motor operators; however, the characteristics and limitations of these devices must be thoroughly understood by the user. The positions outlined in Regulatory Guide 1.106 allow sufficient flexibility to protect safety-related valve operators without degrading system function.

NRC is currently processing a proposed Revision 2 to Regulatory Guide 1.106 in an effort to encourage use of thermal overload devices and to provide an alarm function.

Since thermal overload protection devices can be arranged to disable safety-related motor-operated valves and thus prevent the valves from moving to fulfill a safety function, NRC has provided guidance to licensees in Regulatory Guide 1.106 in order to ensure that the thermal overload protection device itself does not become a potential weak-link failure mechanism.

The purpose of the regulatory guide (RG 1.106) is to ensure that the valve operator motor will not be disabled by either spurious trips or premature trips of the thermal overload device and thus be prevented from performing its safety function.

The basis for AEOD's concern is that the NRC staff's stated regulatory position, as contained in Regulatory Guide 1.106, has encouraged licensees to bypass, or otherwise excessively compromise, thermal overload protection for the valve operators beyond desirable limits.

The general conclusions and recommendations of this report are summarized as follows:

Additional guidance should be included in Regulatory Guide 1.106 concerning use of alarms to indicate an overload situation whether or not the valve operator is disabled by the thermal overload device. A proposed Revision 2 of the regulatory guide is now under consideration. If adopted, that revision would provide guidance for the use of thermal overload devices as nondisabling alarms. As part of the revision to the regulatory guide, consideration is being given to eliminating the current position that allows thermal overload devices to be bypassed at all times, except during stroke testing.

The design, sizing, and circuitry logic for thermal overload protection devices for valve motor operators can vary quite widely. Many thermal overload problems involve improper engineering in the choice, sizing, placement, or maintenance of thermal overload devices.

Industry guidance in this area is lacking.

to 000729 Page 2 of 4 The use of thermal overload relays to provide the means to automatically protect valve operator motors from damage is only one means of accomplishing this task. NRC does not explicitly require the use of thermal overload protection in the regulations, standard review plans, or regulatory guides. A search of the standard review plan and standard technical specifications revealed no specific requirement to provide thermal overload protection for safety-related valve operator motors. The operator manufacturer's recommendations regarding thermal overload protection are the only explicit guidance that would mandate installation and use of thermal overload protection devices. Regulatory Guide 1.106 was originally published in response to concerns regarding spurious trips of thermal overload devices that led to disabling of the valve operator when the operator was otherwise capable of performing its intended safety function.

The regulatory guide is written so as to balance the need to protect the valve operator motor against the necessity to ensure that the operator protection is not a hindrance to performance of a safety function. The first position of Regulatory Guide 1.106 would be appropriate to protect those valves whose function is to open or close to perform a single safety-related action and which do not change position thereafter. In effect, the only time that such valve operators would not have thermal overload protection, along with the attendant risk of being spuriously disabled by the thermal overload device, would be when the valve operator is performing its single safety function. When such a valve is being exercised, for test or after maintenance, the thermal overload device would be available to protect the motor and indicate that some anomaly was preventing or hindering movement of the operator.

The NRC staff is proposing to revise Regulatory Guide 1.106. The proposed revision will advocate use of thermal overload protection for safety-related MOVs, advocate that alarms to indicate thermal overload trip be provided and, eliminate the first regulatory position (bypass thermal overload devices except for testing). This will clarify the position of NRC with respect to the use of thermal overload protection. Plant owners may desire to assess their current policies regarding the use of thermal overload protection although the NRC currently does not plan to recommend action for operating plants in the proposed revision to the regulatory guide.

The response from NRR to the (then draft) AEOD Report C203 was highly divided, as evidenced by the individual branch responses contained in Reference 22. Members of those staff organizations responsible for plant system review were opposed to reevaluation of the regulatory guide recommendations. They disputed the conclusions contained in the AEOD report and AEOD's analysis of the events leading to those conclusions. The systems engineers argued that Regulatory Guide 1.106 balanced system function against overload protection appropriately.

Another argument offered by AEOD to support the need for increased thermal overload protection was that long-term, nondisabling deterioration might lead to valve failure when the valve was challenged (for example, during a design basis event). Obviously, this phenomenon has been difficult to confirm from the currently available failure data bases.

The disagreement within the NRC staff organizations centered around the assessment of reliability of thermal overload devices to protect the motor without interfering with the safety function.

The standard technical specifications do not provide any guidance concerning which position of Regulatory Guide 1.106 is to be used for a particular application. There is no to 000729 Page 3 of 4 need to modify the standard technical specifications since they do not require the use of thermal overload devices or bypass devices or prohibit the use of either.

The NRC issued RG 1.106 R2, in February 2012. In the Staff Regulatory Guidance section of the regulatory guide, the following is stated:

To ensure that safety-related motor-operated valves whose motors are equipped with thermal overload protection devices integral with the motor starter will perform their function, one of the three alternatives described in regulatory position 1 as well as regulatory positions 2 and 3, should be implemented:

1. Provided that the completion of the safety function is not jeopardized or that other safety systems are not degraded:

a) For valves that are required to function immediately to open or close during a Design Basis Event (DBE) or Station Blackout (SBO) to perform a single safety-related action and that do not change position thereafter, the thermal overload protection devices should be continuously bypassed, and should be temporarily placed in service only when the valve motors are undergoing periodic or maintenance testing.

It was noted throughout NUREG-1296 that the use of TOL protection devices do not always protect the station from events. RG 1.106 R2 further illustrates the importance of the selection of the trip setting of thermal overload protections devices, when selecting regulatory Position 2, and emphasized always conservatively setting the protection devices in favor of completing the safety-related action.

The selection of the trip setting of the thermal overload protection devices should be established with all uncertainties resolved in favor of completing the safety-related action.

The NRC issues regulatory guides to describe and make available to the public methods that the NRC staff considers acceptable for use in implementing specific parts of the agencys regulations, techniques that the staff uses in evaluating specific problems or postulated accidents, and data that the staff needs in reviewing applications for permits and licenses. Regulatory guides are not substitutes for regulations, and compliance with them is not required. Methods and solutions that differ from those set forth in regulatory guides will be deemed acceptable if they provide a basis for the findings required for the issuance or continuance of a permit or license by the Commission. Current licensees may continue to use guidance the NRC found acceptable for complying with the identified regulations as long as their current licensing basis remains unchanged. During regulatory discussions on plant specific operational issues, the staff may discuss with licensees various actions consistent with staff positions in this regulatory guide, as one acceptable means of meeting the underlying NRC regulatory requirement. Such discussions would not ordinarily be considered backfitting even if prior versions of this regulatory guide are part of the licensing basis of the facility. However, unless this regulatory guide is part of the licensing basis for a facility, the staff may not represent to the licensee that the licensees failure to comply with the positions in this regulatory guide constitutes a violation.

The NRC staff does not intend or approve any imposition or backfitting of the guidance in this regulatory guide. The NRC staff does not expect any existing licensee to use or commit to using the guidance in this regulatory guide, unless the licensee makes a change to its licensing basis. The NRC staff does not expect or plan to request licensees to voluntarily adopt this regulatory guide to resolve a generic regulatory issue. The NRC to 000729 Page 4 of 4 staff does not expect or plan to initiate NRC regulatory action which would require the use of this regulatory guide. Examples of such unplanned NRC regulatory actions include issuance of an order requiring the use of the regulatory guide, requests for information under 10 CFR 50.54(f) as to whether a licensee intends to commit to use of this regulatory guide, generic communication, or promulgation of a rule requiring the use of this regulatory guide without further backfit consideration.

If a licensee believes that the NRC is either using this regulatory guide or requesting or requiring the licensee to implement the methods or processes in this regulatory guide in a manner inconsistent with the discussion in this Implementation section, then the licensee may file a backfit appeal with the NRC in accordance with the guidance in NUREG-1409 and NRC Management Directive 8.4.

to 000729:

NUREG-0881 Supplement 5, WCGS Safety Evaluation Report Page 8-3 with Section 8.3.3.1.2 Thermal-Overload Protection Bypass (February 1985) 2 Pages

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(2) period of time at the remote panel.

The results of the staff evaluation for this item are reported in Section 9.5.1.5.

The output re~ays of the redundant load sequencers are mounted back to back in a common panel.

In regard to this concern, it is the staff position, in accordance with Section 4.6 of IEEE 308-1974, that the load sequencer be physically sepa-rated from its redundant counterpart or mechanically protected as required 0

to prevent the occurre~ce of a common failure mode.

The applicant responded to this concern by letter dated August 10, 1983.

The output relays of each load group load shedder emergency load sequencer (LSELS) are mounted on their own metal subpanel.

Each subpanel is mounted on a C-channel that, in turn, is bolted to the sides of the panel bay..

This arrangement provides an approximate 2-in. air space between the bar-riers and full side-to-side isolation of the two output relay sections.

External cables for the two relay sections enter the bay from the top and bottom, respectively.

In the area where the cables enter the cabinet, a 6-in. train separation is provided for the cables.

No postulated failure in one output relay section can propagate to the other output relay section.

The staff agrees with the applicant's assessment and concludes that there

'is reasonable assurance that failure in one output relay section will not propagate to the other relay section.

8.2.3 Common Electrical Features and Requirements 8.3.3.l Compliance With GDC 2 and 4 8.3.3.1.2 Thermal-Overload Protection Bypass The staff indicated in the SER that the setpoints for the thermal overload protection, their required margin, and the frequency for per.iodic tests would be included in the Technical Specifications.

By Revision 10 to the FSAR, the applicant indicated that the thermal overload relay trip contacts for all Class lE valves will be permanently bypassed with jumpers before fuel loading.

The staff concludes that the permanent bypass resolves the original SER concern relating to inadvertent operation-of thermal overloads under accident condi-tions; thus, Technical Specifications for this item are no longer required.

The staff notes, however~ that it is not the intent of RG 1.106 to totally eliminate the use of thermal overloads on motor-operated valves.

RG 1.106 is intended to ensure that, under accident conditions, the valve will not be hin-dered from performing its safety function by a spurious trip of its thermal overload protective circuits.

For the majority of valve operations such as during valve test or operation during nonaccident conditions, the use of ther-mal overload protective circuits is a prudent operational practice to minimize motor damage as a result of overload.

This is only a staff observation, and it is not considered an open or confirmatory item.

Wolf Creek SSER 5 8-3

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Position on Thermal Overload Protection in WCNOC-85 and AP 23D-001 3 Pages

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Drawing E-K3EF03, Schematic Diagram Screen Wash Water Valves 1 Page