ML18290A602

Alternative Requests Related to the Fifth and Fourth 10-Year Interval Pump, Valve, and Snubber Inservice Testing Programs, Respectively (EPID L-2018-LLR- 0012 Through EPID L-2018-LLR-0022)

ML18290A602
Person / Time
Site:	Millstone
Issue date:	11/13/2018
From:	James Danna Plant Licensing Branch 1
To:	Stoddard D Dominion Energy Nuclear Connecticut
Guzman R V
References
EPID: L-2018-LLR-0012, EPID: L-2018-LLR-0013, EPID: L-2018-LLR-0014, EPID: L-2018-LLR-0015, EPID: L-2018-LLR-0016, EPID: L-2018-LLR-0017, EPID: L-2018-LLR-0018, EPID: L-2018-LLR-0019, EPID: L-2018-LLR-0020, EPID: L-2018-LLR-0021, EPID: L-2018-LLR-0022
Download: ML18290A602 (33)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 Mr. Daniel G. Stoddard Senior Vice President and Chief Nuclear Officer Innsbrook Technical Center 5000 Dominion Blvd. Glen Allen, VA 23060-6711 November 13, 2018

SUBJECT:

MILLSTONE POWER STATION, UNIT NOS. 2 AND 3-ALTERNATIVE REQUESTS RELATED TO THE FIFTH AND FOURTH 10-YEAR INTERVAL PUMP, VALVE, AND SNUBBER INSERVICE TESTING PROGRAMS, RESPECTIVELY (EPID L-2018-LLR-0012

-THROUGH EPID L-2018-LLR-0022)

Dear Mr. Stoddard:

By letter dated March 1, 2018 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML 18066A078), as supplemented by letters dated July 19, 2018, and August 6, 2018 (ADAMS Accession Nos. ML 18205A 176 and ML 18225A066, respectively), and e-mail dated October 12, 2018 (ADAMS Accession No. ML 18285A 152), Dominion Energy Nuclear Connecticut, Inc. (DENC, the licensee), submitted alternative requests for the fifth 10-year interval inservice testing (1ST) program at Millstone Power Station, Unit No. 2 (Millstone 2), and for the fourth 10-year interval 1ST program at Millstone Power Station, Unit No. 3 (Millstone 3 ). The licensee requested relief from certain 1ST requirements of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants. For Millstone 2, DENC requested the following relief requests:

1. P-01 -Categorization of Low Pressure Safety Injection Pumps as Group A/B 2. P-02 -Smooth Running Pumps 3. V-01 -Refueling Water Storage Tank Back-leakage Valves Leakage Test Frequency

4. V-02 -Firewater to Auxiliary Feedwater Pump Suction Header Manual Valve Test Frequency

5. S-01 -Use of Code Case OMN-13 Revision 2 for the Visual Examination of Snubbers For Millstone 3, DENC requested the following relief requests:

1. P-01 -Safety Injection Pump Cooling Pump Flow Measurement

2. P-02 -Categorization of the Residual Heat Removal Pumps as Group A/B 3. P-03 -Smooth Running Pumps 4. P-04-Use of Code Case OMN-16 5. P-05 -Charging Pump Periodic Verification Test 6. S-01 -Use of Code Case OMN-13 Revision 2 for the Visual Examination of Snubbers D. Stoddard Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) Section 50.55a(z)(1), the U.S. Nuclear Regulatory Commission (NRC) staff concluded, in the enclosed safety evaluation, that relief requests P-01, P-02, V-01, and S-01 for the Millstone 2 fifth 10-year 1ST interval, and relief requests P-02, P-03, P-04, and S-01 for the Millstone 3 fourth 10-year 1ST interval.

are authorized on the basis that the proposed alternatives provide an acceptable level of quality and safety. Pursuant to 1 O CFR 50.55a(z)(2), the staff concluded in the enclosed safety evaluation that relief request V-02 for the Millstone 2 fifth 10-year interval, and relief request P-01 for the Millstone 3 fourth 10-year 1ST interval are authorized on the basis that that the proposed alternative would provide reasonable assurance of pump and snubber operability and compliance with the Code requirements, and compliance with the specified Code requirements would result in hardship or unusual difficulty, without a compensating increase in the level of quality and safety.

The licensee withdrew alternative request P-05 for Millstone 3 by letter dated August 6, 2018. If you have any questions, please contact the Millstone Project Manager, Richard Guzman, at 301-415-1030 or by e-mail to Richard.Guzman@nrc.gov.

Docket Nos. 50-336 and 50-423

Enclosure:

Safety Evaluation cc: Listserv Sincerely, es G. Danna, Chief ant Licensing Branch I Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION ALTERNATIVE REQUESTS RELATED TO THE INSERVICE TESTING PROGRAM FIFTH AND FOURTH 10-YEAR INSERVICE TESTING INTERVALS DOMINION NUCLEAR CONNECTICUT, INC. MILLSTONE POWER STATION, UNIT NOS. 2 AND 3 DOCKET NOS. 50-336 AND 50-423

1.0 INTRODUCTION

By letter dated March 1, 2018 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML 18066A078), as supplemented by letters dated July 19, 2018, and August 6, 2018 (ADAMS Accession No. ML 18205A 176 and ML 18225A066, respectively) and e-mail dated October 12, 2018 (ADAMS Accession No. ML 18285A152), Dominion Energy Nuclear Connecticut, Inc. (DENC, the licensee), submitted alternative requests for the fifth 10-year inservice testing (1ST} program interval at Millstone Power Station, Unit No. 2 (Millstone 2), and for the fourth 10-year 1ST program interval at Millstone Power Station, Unit No. 3 (Millstone 3). The licensee requested alternatives to certain 1ST requirements of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code). The fifth 10-year 1ST interval for Millstone 2, and fourth 10-year 1ST interval for Millstone 3, start on December 2, 2018. The U.S. Nuclear Regulatory Commission (NRC) staff evaluation of the alternative requests is contained herein.

2.0 REGULATORY EVALUATION

The regulation in 10 CFR 50.55a{f), "Preservice and inservice testing requirements," requires, in part, that 1ST of certain ASME Code Class 1, 2, and 3 components must meet the requirements of the ASME OM Code and applicable addenda, except where alternatives have been authorized pursuant to paragraph 10 CFR 50.55a(z)( 1) or 10 CFR 50.55a(z)(2).

In proposing alternatives, a licensee must demonstrate that the proposed alternatives provide an acceptable level of quality and safety (10 CFR 50.55a(z)(1)), or compliance would result in hardship or unusual difficulty, without a compensating increase in the level of quality and safety (10 CFR 50.55a(z)(2)}.

Section 50.55a of 10 CFR allows the U.S. Nuclear Regulatory Commission (NRC) to authorize alternatives and to grant relief from ASME Code requirements upon making the necessary findings.

Based on the above, and subject to the following technical evaluation, the NRC staff finds that regulatory authority exists for the licensee to request, and the Commission to authorize, the alternatives requested by the licensee.

Enclosure 3.0 TECHNICAL EVALUATION OF MILLSTONE 2 ALTERNATIVE REQUESTS 3.1 Licensee's Alternative Request P-01 The request is proposed in accordance with 10 CFR 50.55a(z)( 1) for the duration of the fifth 10-year 1ST program interval at Millstone

2. The NRC staff notes that a similar alternative request was authorized for the fourth 10-year 1ST program interval at Millstone 2 in letter dated October 24, 2008 (ADAMS Accession No. ML082470622).

Applicable Code Requirements ASME OM Code 2012 Edition ISTB-1400, "Owner's Responsibility," (b}, states, "[The Owner's responsibility includes]

identifying each pump to be tested in accordance with the rules of this Subsection, categorizing it as either a Group A or Group B pump, and listing the pumps in the plant records (see ISTB-9000).

A pump that meets both Group A and Group B definitions shall be categorized as a Group A pump." Affected Components The request applies to the Low Pressure Safety Injection (LPSI) pumps P-42A and P-42B, which are Group A/B, ASME Code Class 2 pumps. Reason for Request The licensee states: Pursuant to 10 CFR 50.55a, Codes and Standards, paragraph (z)( 1 ), relief is requested from the requirement of ASME OM Code ISTB-1400(b).

This relief will result in testing the Low Pressure Safety Injection pumps as Group B rather than Group A during power operations.

This proposed relief will result in a lower potential for pump degradation due to pump wear while maintaining the capability of measuring pump performance.

The basis of the relief request is that the proposed alternative would provide an acceptable level of quality and safety. The LPSI pumps meet the categorization.requirements of Group A pumps in that they are operated routinely during plant shutdowns and refueling outages. However, these pumps also meet the requirements of Group B, in that during normal operation (reactor critical) they are not operated except for testing. Proposed Alternative and Basis for Use The licensee states: DENC proposes that the LPSI pumps (P-42A and P-42B) be tested as standby pumps (Group B) during power operation and as continuously operating pumps (Group A) during refueling operations.

During refueling operations, the comprehensive pump test may be substituted for a quarterly Group A test that comes due. DENC also proposes that any time a comprehensive pump test is performed, the Code-required quarterly low-flow test (Group B) requirement may be deleted for that quarter. The quarterly pump test is procedurally controlled to ensure that flow rates are maintained above the pump manufacturers recommended minimum flow requirements (100 gallons per minute (gpm)) and that the pumps are not operated longer than 30 minutes to ensure that pump degradation is minimized during the quarterly pump test. These pumps are vertical line shaft centrifugal type pumps that provide the low head safety injection function during power operations and provide reactor core cooling during the cooldown phase of shutdown cooling. During normal power operations, the LPSI pump is in a standby condition and is considered an essential part of the Emergency Core Cooling System (ECCS). Each pump starts automatically upon receipt of a safety injection actuation signal (SIAS), taking suction from the Refueling Water Storage Tank during the injection phase of an accident.

The pumps discharge to the re~ctor coolant system. ISTB-1400(b) states that if a pump meets both Group A and Group B definitions, it shall be categorized as a Group A pump. The LPSI pumps are currently tested during normal operation using the minimum flow recirculation loop. The design flow rate for each Low Pressure Safety Injection pump is 3000 gpm. This flow rate can only be achieved during shutdown periods when injection into the reactor coolant system at a reduced pressure is possible.

Classifying these pumps as Group B during power operation minimizes the time required to perform quarterly testing. With minimum pump run-time requirements, and no requirements to record vibration levels, the length of each quarterly pump test and the accompanying unavailability time for these pumps should be reduced. Since these pumps are not operated routinely during plant operation, except for required surveillance testing, there is no time or wear-related degradation mechanism that would warrant performing more detailed quarterly tests on the LPSI pumps. NUREG/CP-0137, Vol. 1, "Proceedings of the Third NRG/American Society of Mechanical Engineers (ASME) Symposium on Valve and Pump Testing," includes a report entitled, "Description of Comprehensive Pump Test Change to ASME Code, Subsection ISTB." This report details the philosophy of classifying pumps as Group A or Group B. According to the author, the intent of having different test requirements for different pump groups is to relate the requirements for the amount and degree of quarterly performance monitoring to the amount of degradation expected based on pump operation.

Testing the LPSI pumps quarterly as Group A pumps during power operation is contrary to the philosophy of the referenced report. Quarterly Group A testing would subject these pumps to increased test requirements and performance monitoring.

It would also introduce the potential for more degradation due to pump wear (caused by low-flow operation) at a time when they are standby pumps and would not otherwise be subject to operation-induced degradation. Group A testing during power operation may be more detrimental to the long-term health of these components than Group B testing. In Generic Letter (GL) 89-04, "Guidance on Developing Acceptable lnservice Testing Programs", (ADAMS Accession No. ML031150259), Position 9, the NRC determined that, in cases where flow can only be established through a non-instrumented, minimum-flow path during quarterly pump testing, and a path exists at cold shutdown or refueling outages to perform a test of the pump under full or substantial flow conditions, the increased interval for flow measurement is an acceptable alternative to the Code requirements.

The proposed alternative to the specific requirements of ISTB-1400(b) identified above would provide adequate indication of pump performance and continue to provide an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(z)( 1 ), DENC requests approval of this proposed alternative to the specific ISTB requirements identified in this request. NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Section ISTB-1400(b), requires that pumps be categorized as either Group A or Group B pumps and requires that pumps meeting both definitions are categorized as Group A. In lieu of these requirements of ISTB-1400(b), the licensee has proposed that the LPSI pumps be tested as standby pumps (Group B) during Modes 1 through 4, and as continuously operating pumps (Group A) during Modes 5 and 6. In Modes 5 and 6, the comprehensive pump test (CPT) may be substituted for a quarterly Group A test that comes due during a mid-cycle cold shutdown period, as provided by Subsection ISTB of the ASME OM Code. ISTB-5000 states that when a Group A test is required, a CPT may be substituted.

The licensee states that a CPT will be performed instead of a Group A test during Modes 5 and 6. ISTB-2000 defines Group A pumps as "pumps that are operated continuously or routinely during normal operation, cold shutdown, or refueling operations;" and Group B pumps as "pumps in standby systems that are not operated routinely except for testing." Based on these definitions, the LPSI pumps meet the definition of Group B pumps during normal operation in Modes 1 through 4. In Modes 5 and 6, the LPSI pumps are used for shutdown cooling and meet the definition of Group A pumps. 1STB-1400(b) states that "A pump that meets both Group A and Group B pump definitions shall be categorized as a Group A pump." This would normally cause the LPSI pumps to be classified as Group A. However, because of the inability to achieve a substantial flow rate in Modes 1 through 4, to the licensee cannot conduct a Group A test that would provide much meaningful data to detect degradation due to the relatively flat profile of the pump hydraulic curve and the higher vibration levels present at these near shutoff head flow conditions.

Additionally, the LPSI pumps are standby pumps during Modes 1 through 4, and little degradation is expected with respect to hydraulic performance during the operational period when the pumps are idle. In GL 89-04, Position 9, the NRC determined that, in cases where flow can only be established through a non-instrumented, minimum flow path during quarterly pump testing, and a path exists at cold shutdown or refueling outages to perform a test of the pump under full or substantial flow conditions, the increased interval is an acceptable alternative to the ASME OM Code requirements.

The quarterly Group B test will be performed using the minimum recirculation flow path under low-flow conditions and only flow will be measured.

Additionally, during Modes 5 and 6 ( during refueling outages and cold shutdowns), a CPT will be performed instead of a Group A test. Millstone 2 Technical Specification (TS) Surveillance Requirement (SR) 4.5.2, d requires verification that each LPSI pump's developed head at the flow test point is greater than or equal to the required developed head in accordance with the frequency established by the 1ST program. This TS requirement will be performed at the frequency required by the modified 1ST program. The proposed alternative testing of the LPSI pumps as Group B during Modes 1 through 4, and as Group A during Modes 5 and 6, is consistent with GL 89-04, Position 9, and provides reasonable assurance of operational readiness of the LPSI pumps. Therefore, the NRC staff finds that the proposed alternative will provide an acceptable level of quality and safety. The licensee referenced a paper titled "Description of Comprehensive Pump Test Change to ASME OM Code, Subsection ISTB" that is included in NUREG/CP-0137, Volume 1. This NUREG is a compilation of papers presented at an NRC/ASME Symposium on Valve and Pump Testing. The NRC staff notes that statements and opinions advanced in the papers presented at the symposium are individual expressions of the authors and not those of either ASME or the NRC. 3.2 Licensee's Alternative Request P-02 The request is proposed in accordance with 10 CFR 50.55a(z)(1) for the duration of the fifth 10-year 1ST program interval at Millstone

2. Applicable Code Requirements ASME OM Code 2012 Edition ISTB-3300, "Reference Values," (a), requires that initial reference values shall be determined from the results of testing meeting the requirements of paragraph ISTB ... 3100, Preservice Testing, or from the results of the first inservice test. ISTB-3300, "Reference Values," (b), requires that new or additional reference values shall be established as required by paragraph ISTB-3310 or ISTB-3320, or subparagraph ISTB-6200(c).

ISTB-3300, "Reference Values," (f), requires that all subsequent test results shall be compared to these initial reference values or to new reference values established in accordance with paragraph ISTB-3310 or ISTB-3320, or subparagraph ISTB-6200(c). ISTB-5121, "Group A Test Procedure," (e), and ISTB-5123, "Comprehensive Test Procedure," (e), require for centrifugal pumps during their Group A test and comprehensive test that all deviations from the reference values shall be compared with the ranges of Table ISTB-5121-1, and corrective action taken as specified in paragraph ISTB-6200.

Vibration measurements shall be compared to both the relative and absolute criteria shown in the alert and required action ranges of Table ISTB-5121-1.

For example, if vibration exceeds either 6Vr [vibration reference value] or 0.7 inches/seconds (in/sec), the pump is in the required action range. ISTB-5221, "Group A Test Procedure," (e), and ISTB-5223, "Comprehensive Test Procedure," (e), require for vertical line shaft centrifugal pumps during their Group A test and comprehensive test that all deviations from the reference values shall be compared with the ranges of Table ISTB-5221-1, and corrective action taken as specified in paragraph ISTB-6200.

Vibration measurements shall be compared to both the relative and absolute criteria shown in the alert and required action ranges of Table ISTB-5221-1.

For example, if vibration exceeds either 6Vr or 0. 7 in/sec, the pump is in the required action range. ISTB-5321, "Group A Test Procedure," (e), and ISTB-5323, "Comprehensive Test Procedure," (e), require for positive displacement pumps during their Group A test and comprehensive test that all deviations from the reference values shall be compared with the ranges of Table ISTB-5321-1 or Table ISTB-5321-2, as applicable, and corrective action taken as specified in paragraph ISTB-6200.

For reciprocating positive displacement pumps, vibration measurements shall be compared to both the relative and absolute criteria shown in the alert and required action ranges of Table ISTB-5321-2.

For all other positive displacement pumps, vibration measurements shall be compared to both the relative and absolute criteria shown in the alert and required action ranges of Table ISTB-5321-1.

For example, if vibration exceeds either 6Vr or 0.7 in/sec, the pump is in the required action range. Affected Components The request applies to smooth running pumps in the 1ST program. In response to Request for Additional Information (RAI) 2P-02-1 in the letter dated July 19, 2018, the licensee provided the following table of affected pumps that have at least one vibration reference value less than 0.05 inches per second (ips). Pump ID Pump Name ASME Code Class Pump Group P-13A 'A' Spent Fuel Pool Coolino Pump 3 A P-13B 'B' Spent Fuel Pool Cooling Pump 3 A P-19B 'B' Boric Acid Pump 2 A P-41A 'A' Hioh Pressure Safety Injection Pump 2 B P-41B 'B' High Pressure Safety Injection Pump 2 B P-41C 'C' High Pressure Safety Injection Pump 2 B P-42A 'A' Low Pressure Safety Injection Pump 2 A P-42B 'B' Low Pressure Safety Injection Pump 2 A Reason for Request The licensee states: Pumps with vibration reference value (Vr) < 0.05 ips are identified as smooth running pumps. Each smooth running pump has at least one Vr that is currently less than 0.05 ips. Small values for Vr produce small acceptable ranges for pump operation.

The acceptable ranges are defined in Tables ISTB-5121-1, ISTB-5221-1, ISTB-5321-1, and ISTB-5321-2 as less than or equal to 2.5Vr. Based on the small acceptable range, a smooth running pump could be subject to unnecessary increased testing if the measured vibration parameter exceeds this acceptable range. For very small reference values, hydraulic noise and instrument error can be a significant portion of the reading and affect the repeatability of subsequent measurements.

Also, operating experience from the Millstone Power Station Predictive Maintenance Program has shown that changes in vibration levels in the range of 0.05 ips do not normally indicate significant degradation in pump performance.

It should be noted that all of the pumps in the 1ST Program will remain in the Predictive Maintenance Program even if certain pumps have very low vibration readings and are considered to be smooth running pumps. Proposed Alternative and Basis for Use The licensee states: To avoid unnecessary increased testing, a minimum value for Vr of 0.05 ips has been proposed for velocity measurements.

This minimum value will be applied to individual vibration locations for certain pumps whose measured reference value is less than 0.05 ips. When new reference values are established per ISTB-3310, ISTB-3320 or 1STB-6200(c}, the measured parameters would be evaluated for each location to determine if the minimum value for Vr would apply. In addition to the requirements of 18TB, the pumps in the ASME lnservice Testing Program are included in the Millstone Predictive Maintenance Program. The Millstone Predictive Maintenance Program currently employs predictive monitoring techniques such as:

• Vibration monitoring and analysis beyond that required by 18TB,

• Oil sampling and analysis where applicable (e.g., for pumps with sufficiently large oil reservoirs).

If the measured parameters are outside the normal operating range or are determined by analysis to be trending toward an unacceptable degraded state, appropriate actions are taken that may include:

• Increased monitoring to establish rate of change,

• Review of component specific information to identify cause, or

• Removal of the pump from service to perform maintenance.

For the smooth running pumps, if a measured reference value is below 0.05 ips for a particular vibration measurement location, then subsequent test results for that location may be compared to an acceptable range based on 0.05 ips. In addition to the Code requirements, the pumps in the 1ST Program are included in and will remain in the Millstone Predictive Maintenance Program even if certain pumps have very low vibration readings and are considered to be smooth running pumps. Also, appropriate actions will be taken if measured parameters are outside the normal operating range or are determined to be trending toward a degraded state. This proposed alternative to the requirements of ISTB-3300, ISTB-5100, ISTB-5200, ISTB-5300 and the associated tables provides adequate indication of pump performance and continues to provide an acceptable level of quality and safety. NRC Staff Evaluation The 2012 Edition of the ASME OM Code requires that the vibration of all safety-related pumps be measured; ISTB-3540 describes the measurements to be taken. These measurements are required to be compared with the vibration acceptance criteria specified in Tables ISTB-5121-1, ISTB-5221-1, ISTB-5321-1, and ISTB-5321-2 for centrifugal, vertical line shaft, positive displacement, and reciprocating positive displacement pumps, respectively, to determine if the measured values are acceptable.

Table ISTB-5121-1 shows that, if during an inservice test, a vibration measurement on a centrifugal pump exceeds 2.5 times the reference value (Vr) previously established as required by ISTB-3300, the pump is considered to be in the alert range. The frequency of testing is then doubled in accordance with ISTB-6200(a) until the cause of the deviation is determined, the condition is corrected, and the vibration level returns below the alert range, or an analysis of the pump is performed in accordance with ISTB-6200(c).

Per ISTB-6200(b), if pump vibration is found to be greater than 6 times Vr, then the pump is considered to be in the required action range and must be declared inoperable until either the cause of the deviation has been determined and the condition is corrected or an analysis of the pump is performed in accordance with ISTB-6200(c).

Per ISTB-3300(c), the vibration reference values shall be established only when the pump is known to be operating acceptably.

For pumps whose absolute magnitude of vibration is an order of magnitude below the absolute vibration limits of the acceptance criteria, a relatively small increase in vibration magnitude may cause a pump to enter the alert or required action range, even though the pump is operating acceptably.

The pump may enter these ranges due to variations in flow, instrument accuracies, or other noise sources that would not be associated with degradation of the pump. Pumps that operate with these low vibrations are typically referred to as "smooth running." Since the acceptable range for a "smooth running" pump is so small, the pump could be subjected to unnecessary corrective action due to entry into the alert or action ranges. The NRC has previously authorized a minimum vibration level of 0.05 ips for "smooth running" pumps at several nuclear plants. However, experience has shown that only monitoring the vibration of "smooth running" pumps has not been sufficient for determining pump degradation.

At one particular plant, the NRC authorized a minimum reference value of 0.1 ips. A pump ,bearing at this plant experienced a significant degradation, even though the pump vibration levels were below the minimum reference value in the approved alternative.

The bearing degradation was discovered during predictive maintenance program activities.

The licensee's alternative combines a minimum vibration value of 0.05 ips for "smooth running" pumps with additional monitoring using a predictive maintenance program that includes vibration monitoring and analysis beyond that required by the ASME OM Code, as well as oil sampling and analysis where applicable.

The licensee notes in its alternative request that if any of the measured parameters, including predictive maintenance values, are outside of the normal operating range or are determined by analysis to be trending towards an unacceptable degraded state, appropriate actions will be taken. These actions include increased monitoring to establish a rate of change, review of component-specific information to identify the cause of the condition, and removal of the pump from service to perform maintenance.

The proposed alternative is consistent with the objectives of the 1ST program, which is to monitor degradation in safety-related components. Based on the minimum vibration reference value of 0.05 ips noted in this request and the proposed predictive maintenance program, the NRC staff finds that the alert and required action limits specified in the request should address previously undetected pump problems and provide an adequate indication of pump performance.

The licensee's predictive maintenance program is designed to detect problems involving unacceptable mechanical conditions in advance of when a smooth running pump may reach the overall vibration alert or action limits. Therefore, the NRC staff finds that the proposed alternative will provide an acceptable level of quality and safety. 3.3 Licensee's Alternative Request V-01 The request is proposed in accordance with 10 CFR 50.55a(z)( 1) for the duration of the fifth 10-year 1ST program interval at Millstone

2. The NRC staff notes that a similar alternative request was authorized for the fourth 10-year 1ST program interval at Millstone 2 in the letter dated October 24, 2008. Applicable Code Requirements ASME OM Code 2012 Edition ISTC-3630, "Leakage Rate for Other Containment Isolation Valves," states, "Category A valves with a leakage requirement not based on an Owner's 10 CFR 50, Appendix J program, shall be tested to verify their seat leakages within acceptable limits. Valve closure before seat leakage testing shall be by using the valve operator with no additional closing force applied." ISTC-3630, "Frequency," (a}, states, "Tests shall be conducted at least once every 2 [years]." Affected Components By the e-mail dated October 12, 2018, the licensee stated that valves 2-CS-050 and 2-CS-051 should be re-classified as Category B valves (instead of Category A) and that it will update the Millstone 2 1ST plan accordingly to reflect the change. Therefore, the staff's evaluation for alternative request V-01 applies to the valves listed in the following table. Valve ASME Category Function Number Code Class 2-CS-14A 2 AC Refuelino Water Storaoe Tank Outlet Header Check Valve 2-CS-14B 2 AC RWST [Refueling Water Storage Tank] Outlet Header Check Valve 2-Sl-459 2 A Safety Injection System Test Header Downstream Isolation Valve 2-Sl-460 2 A Low Pressure Safety Injection/Containment Spray Test Header Stop Valve 2-Sl-659 2 A Engineered Safeguards Features (ESF) Pumps Min Flow Recirculation Header Isolation Valve 2-Sl-660 2 A ESF Pumps Min Flow Recirculation Header Isolation Valve Reason for Request The licensee states: Pursuant to 10 CFR 50.55a, "Codes and Standards," paragraph (z)(1), relief is requested from the requirement of ASME OM Code ISTC-3630(a).

ISTC-3630(a) requires leakage testing of category A valves, other than containment isolation valves, on a two year frequency.

These valves are required to close or remain closed to prevent back-leakage to the RWST during the recirculation phase of a Loss of Coolant Accident (LOCA). The subject valves function as a system during the sump recirculation phase of a LOCA to prevent backflow into the RWST and limit the potential for a release of radioactivity from inside containment to the atmosphere.

The RWST is vented to atmosphere.

The total allowable leakage limit for this system of valves is based on the calculated site boundary dose limits and control room habitability limits. Individual leak rates of the subject valves can vary as long as the total back-leakage from the valves into the RWST is maintained less than the assumed calculated limits. Administrative leakage limits have been calculated for each of the subject valves. See Table 1, "Measured Leakage Results for RWST Back-Leakage Valves" for a history of seat leakage results. Historical leakage rates for each of these valves, as tabulated in Table 1, indicates measured leak rates well below the administrative limits over the past several tests. The data indicates reasonable assurance that the valves will perform their intended function, and that leakage will not exceed the administrative limits from test to test. Therefore, extension of the test frequency is warranted.

Proposed Alternative and Basis for Use The licensee states: ISTC-3630(a) requires leakage testing of category A valves, other than containment isolation valves, on a two year frequency.

DENC proposes that the subject valves be exempt from the 2 year leak test frequency requirement of ISTC-3630(a) for Category A valves whose closing function prevents back-leakage to the Refueling Water Storage Tank (RWST) during post LOCA sump recirculation.

DENC proposes adoption of the performance-based 1 O CFR 50 Appendix J, Option B test frequencies which apply to valves whose function is also isolation of the extended containment boundary while on sump recirculation.

The valves would be tested as follows:

• 2-CS-14A/B would be tested every other refueling;

• 2-CS-050 and 2-CS-051 are two parallel valves in series with 2-Sl-459.

2-Sl-459 would be the valve in the path normally tested every 60 months, with the ability to test 2-CS-050 and 2-CS-051 maintained as an alternative.

• The remainder of the valves would be tested every 60 months If leakage results exceed the administrative limits for a given valve, the subject valve would be leak tested at least once every two years until two consecutive as found tests show a leakage rate below the administrative limit. After two satisfactory tests, the valve would be returned to the test frequency proposed in this relief request. Historical leakage testing results for each of these valves show measured leakages below Millstone 2 administrative limits over a period of nine years. The test data supports the conclusion that it is reasonable to extend the time period between tests from prescribed limits in the ASME OM Code. Performance-based frequency of testing implemented by 10 CFR 50 Appendix J, Option Bis applicable to these valves, whose function is also isolation of the extended containment boundary while on sump recirculation.

Pursuant to 10 CFR 50.55a(z)( 1 ), this proposed alternative would provide an acceptable level of quality and safety.

NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Section ISTC-3630(a) requires that Category A valves with a leakage requirement that is not based on a licensee's 10 CFR Part 50, Appendix J program be leak tested at least every 2 years to verify that seat leakage is within acceptable limits. The licensee has proposed an alternative test in lieu of the requirements of ISTC-3630(a) for eight valves that are classified as Category A valves. Specifically, the licensee proposes to functionally test and verify the leakage rate of the valves listed in the above table using a performance-based schedule in accordance with 1 O CFR Part 50, Appendix J, Option B, which allows extension of the test interval up to 60 months based on historical valve performance.

The staff notes that by the e-mail dated October 12, 2018, valves 2-CS-050 and 2-CS-051 are reclassified to Category B valves; therefore, the request does not apply to these two valves. The table of affected components is updated to reflect this change. Additionally, since these valves are removed from the request, leakage testing of valves 2-CS-050 and 2-CS-051 cannot be maintained as an alternative to leakage testing of valve 2-Sl-459.

Historical leak-test results for each of the affected valves show measured leakages below Millstone 2 administrative limits over a period of 9 years. Measured leakages are, in most cases, an order of magnitude less than the administrative limits. The previous testing and test data support the conclusion that it is reasonable to extend the time period between tests. In addition, these valves are secondary containment isolation valves, and Option B to Appendix J of 1 O CFR Part 50 is applicable to these valves. For the valves listed in the updated table of affected components, the licensee proposed alternative is consistent with Option B to Appendix J of 10 CFR; therefore, the NRC staff finds that the proposed alternative will provide an acceptable level of quality and safety. 3.4 Licensee's Alternative Request V-02 The request is proposed in accordance with 10 CFR 50.55a(z)(2) for the duration of the fifth 10-year 1ST program interval at Millstone

2. The NRC staff notes that a similar alternative request was authorized for the fourth 10-year 1ST program interval at Millstone 2 in the letter dated October 24, 2008. Applicable Code Requirements ASME OM Code 2012 Edition ISTC-3540, "Manual Valves," states, "Manual valves shall be full-stroke exercised at least once every 2 [years], except where adverse conditions may require the valve to be tested more frequently to ensure operational readiness.

Any increased testing frequency shall be specified by the Owner. The valve shall exhibit the required change of obturator position." Affected Components The request applies to the components in the following table. Valve ASME Category Function Number Code Class 2-FIRE-94A 3 2-FIRE-94B 3 2-FIRE-94C 3 Reason for Request The licensee states: B "A" AFW [Auxiliary Feedwater]

Pump Emergency Firewater Supply Valve B "B" AFW Pump Emeroency Firewater Supply Valve B Turbine AFW Pump EmerQencv Firewater Supply Valve Pursuant to 10 CFR 50.55a, "Codes and Standards," paragraph (z)(2), relief is requested from the testing frequency requirement of ASME OM Code ISTC-3540.

DENC proposes to place these valves in a sample exercise program and exercise one valve each refuel outage in lieu of a full-stroke exercise every two years. The basis of this proposed alternative is that the Code required testing results in unusual difficulty without a compensating increase in level of quality or safety. The normally closed, 6-inch, manually operated, gate valves serve as the Firewater/AFW system boundary valves. The normally isolated firewater system provides an alternate source of water to the AFW pumps during long-term cooling in the event the normal condensate storage tank (CST} supply is depleted.

An 8-inch firewater header supplies the three parallel six inch lines, one for each of the three AFW pumps, which tie directly into the normal AFW pump suction paths from the CST. There is no drain path available between the 8-inch header and the three 6-inch isolation valves. Manual full-stroke testing is a burden since the firewater discharge flow path goes directly to the suction of the AFW pumps and cycling the valves would result in chemical and particulate contamination of the AFW system and/or CST. As a result, a spool-piece in each AFW pump suction line must be removed and the firewater routed away from the AFW system using temporary piping. This involves significant maintenance preparation and restoration activities, including temporary piping modifications, proper disposal of the chlorinated firewater, and extensive system flushing after each valve cycle to insure the AFW system does not become contaminated when restored.

One motor driven AFW pump is required to be available during outages to supply emergency makeup to the Spent Fuel Pool. Cycling the three valves at each refueling would negatively impact the outage schedule and the availability of AFW pumps to support this function.

There have been no identified problems from historical exercise testing of these valves during the third or fourth ten-year intervals.

Proposed Alternative and Basis for Use The licensee states: DENC proposes testing 2-FIRE-94A/B/C on a sample frequency of one valve in the group each refueling cycle in lieu of a full-stroke exercise every two years. The basis of this proposed alternative is that the Code required testing results in unusual difficulty without a compensating increase in level of quality or safety. These valves are the same size and model from the same manufacturer, and are installed in the same application and orientation, meeting the grouping methodology allowed in NUREG-1482 for check valve testing. One valve in the group will be manually full-stroked every refueling outage, and all the valves in the group would be manually full-stroked within 3 refueling cycles. If any valve is incapable of being full-stroke exercised, the remaining valves in the group will be manually full-stroke tested in the same outage. A full-stroke exercise test will be performed after any maintenance that could affect the full-stroke capability of the valve. Pursuant to 10 CFR 50.55a(z)(2), this proposed alternative test plan avoids unusual difficulty, lessens the unavailability of safety equipment required during outages, and is adequate to meet the fundamental objective of detecting degradation.

NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Section ISTC-3540, requires (1) full-stroke exercising of manual valves at least once every 2 years, unless adverse conditions require more frequent testing of valves to ensure operational readiness; (2) that the licensee shall specify any increased testing frequency; and (3) that valves shall exhibit the required change of obturator position.

The licensee has proposed an alternative test in lieu of the requirements of ISTC-3540 for the firewater supply valves that are classified as Category B valves. Specifically, the licensee proposes to full-stroke test one of the three valves every refueling cycle with all valves being full-stroke tested within 3 refueling cycles. The three fire water valves isolate the fire water from the suction supply of the AFW system. According to the Final Safety Analysis Report, the operators can connect the fire water system to the AFW pump suctions in the event that the CST becomes depleted and cannot be replenished by normal makeup. In order to exercise each fire water valve without contaminating the AFW system with fire water, the flow path from the CST is isolated and a spool piece is removed between the AFW pump and the fire water isolation valve. Temporary piping is installed to divert the water away from the AFW system. Installing the temporary piping, restoring the system, and flushing the system to prevent AFW system contamination results in significant hardship.

There are no existing valves in the fire water or AFW suction lines that facilitate exercising these valves. Because of the hardship of testing all the affected valves, the licensee is requesting that the testing interval be increased to three refueling outages for each valve. Exercising of each valve will be performed on a staggered basis with one valve being tested each refueling outage. In the event that a valve selected for testing during a refueling outage is not capable of being exercised to its safety position, the other two valves will be exercised during the same refueling outage. In addition, a valve will be exercised to its safety position after any maintenance that could affect the capability of the valve to perform its safety function.

The licensee's proposal to exercise these valves on a sampling basis is similar to the philosophy for disassembly and inspection of check valves of Position 2 of GL 89-04. The licensee stated that all three valves are of the same size, manufacturer, and model number. In addition, these valves are oriented in the same position and see identical service conditions.

There have been no identified problems from historical testing of these valves during the third and fourth 10-year intervals.

Based on the fact that exercising each valve every refueling outage requires significant effort to configure the system for the exercise, the NRC staff finds that compliance with the current Code requirements results in hardship, without a compensating increase in the level of quality and safety. Although the proposed testing increases the exercise interval of each valve from 2 years to three refueling outages, the NRC staff finds that the proposed alternative provides reasonable assurance of operational readiness because the testing is performed on a staggered basis, and the licensee's review of the work history of these valves has not identified any issues. In addition, the proposed alternative is consistent with the philosophy of Position 2 of GL 89-04 regarding sample disassembly and inspection of check valves. Finally, the licensee has committed to: ( 1) exercise the other two valves during the same refueling outage if a valve selected for testing is not capable of being exercised to its safety position, and (2) exercise a valve to its safety position after any maintenance that could affect the capability of the valve to perform its safety function.

3.5 Licensee's Alternative Request S-01 The request is proposed in accordance with 10 CFR 50.55a(z)(1) for the duration of the fifth 10-year 1ST program interval at Millstone

2. Applicable Code Requirements ASME OM Code 2012 Edition ISTD-4252, "Subsequent Examination Intervals," (c), states, "The duration of examination intervals following the completion of the second refueling outage shall be in accordance with Table ISTD-4252-1." ISTA-3130, "Application of Code Cases," (b), states, "Code Cases shall be applicable to the edition and addenda specified in the test plan." Affected Components The request applies to all hydraulic and mechanical snubbers in scope of the 1ST program.

Reason for Request The licensee states: Pursuant to 10 CFR 50.55a, "Codes and Standards," paragraph (z)(1 ), relief is requested from the applicability statement in Revision 2 of Code Case OMN-13 as shown in the 2012 Edition of the ASME OM Code. This request is to allow the use of ASME Code Case OMN-13, Revision 2 with the 2012 Edition of the ASME OM Code. Code Case OMN-13, Revision 2 provides alternative rules for establishing the intervals for the visual examination of snubbers.

Code Case OMN-13, Revision 2 applies to the 1995 Edition through the 2011 Addenda. DENG will implement the 2012 Edition of the ASME OM Code for the fifth 10-year 1 ST interval.

Proposed Alternative and Basis for Use The licensee states: By using Code Case OMN-13, Revision 2, DENG will be able to alter the visual examination intervals currently required by paragraph ISTD-4252(c) of the 2012 Edition of the ASME OM Code. ISTD-4252(c) currently requires that snubbers be visually examined in accordance with Table ISTD-4252-1 of the ASME OM Code, which states that each snubber within the scope of paragraph ISTA-1100 must be visually examined on a frequency not to exceed 48 months. Revision 2 of Code Case OMN-13 permits the user to extend that visual examination frequency to once each ten year interval.

This permission is based on the provisions that the licensee must perform the visual examinations under the code case using the same criterion that would have been used under the Code and, in addition, the following criteria specified in the code case shall also be met: 1. Examination for indications of degradation or severe operating environments

2. Examination prior to maintenance or testing 3. Monitoring of reservoir fluid level 4. Review of Operational Readiness test data 5. Examination during disassembly

6. Transient dynamic event evaluation

7. Corrective action on unacceptable snubbers Based on the additional criteria listed above and the provisions that the original visual examination parameters specified in the 2012 Edition of the ASME OM Code will also be met, the use of Code Case OMN-13, Revision 2, approved by the NRC in Reg. Guide 1.192, will provide at least equivalent assurance that snubbers remain visually acceptable for performing their safety functions.

This proposed alternative to the specific requirements of ISTD-4252(c) identified above will provide adequate visual indication of snubber performance and continue to provide an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(z)( 1 ), DENC requests approval of this proposed alternative to the specific ISTD requirements identified in this request. NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Section ISTD-4252(c), requires snubber examination intervals following the second refueling outage to be in accordance with intervals specified in Table ISTD-4252-1.

The snubber visual examination interval can be extended up to 48 months by meeting the requirements as specified in Table ISTD-4252-1 and its notes. Section 1ST A-3130(b) states that Code Cases shall be applicable to the ASME OM Code edition and addenda specified in the test plan. The licensee has proposed an alternative to the requirements of ISTD-4252(c) and ISTA-3130(b) for all snubbers in the 1ST program. Specifically, the licensee proposes to use ASME OM Code Case OMN-13, Revision 2, which allows extension of the visual examination interval beyond the interval allowed in Table ISTD-4252-1.

Code Case OMN-13 is applicable to the 1995 Edition through the 2011 Addenda of the ASME OM Code; therefore, the. licensee has also proposed to apply Code Case OMN-13 to the 2012 Edition of the ASME OM Code as an alternative to the requirements of ISTA-3130(b).

Application of ASME OM Code Cases is addressed in 10 CFR 50.55a(b )(6) through references to Regulatory Guide (RG) 1.192, Revision 2 (ADAMS Accession No. ML 16321 A337), which lists acceptable and conditionally acceptable Code Cases for implementation in the 1ST program and snubber program. RG 1.192, Revision 2, shows Code Case OMN-13, Revision 2 in Table 1 as acceptable for use without conditions.

Code Case OMN-13, Revision 2, was published with the 2012 Edition of the ASME OM Code, and it is applicable to the 1995 Edition through the 2011 Addenda of the ASME OM Code. There is no technical reason for prohibiting the use of Code Case OMN-13, Revision 2, with the 2012 Edition dlf the ASME OM Code. Further, NRC staff reviewed the 2012 Edition of the ASME OM Code and Code Case OMN-13, Revision 2, and confirmed that there are no changes in the applicable Code sections referenced within Code Case OMN-13, Revision 2. Therefore, the NRC staff concludes that the licensee's proposed alternative provides an acceptable level of quality and safety. 4.0 TECHNICAL EVALUATION OF MILLSTONE 3 ALTERNATIVE REQUESTS 4.1 Licensee's Alternative Request P-01 The request is proposed in accordance with 10 CFR 50.55a(z)(2) for the duration of the fourth 10-year 1ST program interval at Millstone

3. The NRC staff notes that a similar alternative request was authorized for the third 10-year 1ST program interval at Millstone 3 in the letter dated October 24, 2008. Applicable Code Requirements ASME OM Code 2012 Edition ISTB-5122, "Group B Test Procedure," states, "The test parameter value identified in Table ISTB-3000-1 shall be determined and recorded as required by this paragraph." ISTB-5123, "Comprehensive Test Procedure," states, "The test parameters shown in Table ISTB-3000-1 shall be determined and recorded as required by this paragraph." Table ISTB-5121-1, "Centrifugal Pump Test Acceptance Criteria," identifies the acceptance criteria for the test parameter values that are identified in Table ISTB-3000-1 and recorded during Group B and comprehensive tests. Affected Components The request applies to the Safety Injection Pump Cooling (CCI) pumps 3CC*P1A and 3CC*P1 B, which are Group B, ASME Code Class 3 pumps. Reason for Request The licensee states: Pursuant to 10 CFR 50.55a, "Codes and Standards," paragraph (z)(2), relief is requested from the requirement of the ASME OM Code for measuring and recording pump flow. Due to system design and lack of an instrumented minimum flow line, total pump flow cannot be measured during the Group B or comprehensive pump tests. The Safety Injection Pump Cooling (CCI) System is designed to provide 9.5 gpm cooling flow to the Safety Injection Pump Lube Oil cooler. Since the original design flow was approximately 21 gpm and the pump rated flow is 25 gpm, the minimum flow recirculation line was designed with an orifice sized to pass 15 gpm. However, the minimum flow recirculation lines were not designed to allow flow measurement with either permanent or temporary instrumentation which would meet ASME Code requirements.

These lines*were also not designed to be isolated.

As a result, the majority of pump flow during 1ST pump testing is unmonitored.

Figure 1 [in the licensee's submittal]

contains a sketch of the system. Proposed Alternative and Basis for Use The licensee states: Since the pump head versus flow characteristics are relatively flat over the normal operating range for these pumps (see Figure 2, Pump Curve [in the licensee's submittal]), the change in pump differential pressure from rated flow to the shutoff head condition is approximately 3.7%. As a result, a complete obstruction of this unmonitored recirculation flow could only increase pump differential (i.e. mask pump degradation) by an amount less than 3.7%. To account for a complete obstruction of pump recirculation flow, DENC proposes that the lower band required action for differential pressure be changed from 10% to 6% for both the Group B and comprehensive tests. Any increase in recirculation flow, i.e. increase in orifice size, would result in a reduction in pump differential which would be conservatively identified as pump degradation.

Although the minimum flow recirculation lines do not have provisions for isolation, the potential to block flow by installing a blind flange in the restriction orifice was investigated.

Full flow data from the GL 89-13 test program indicated that a maximum of 11 -12 gpm is obtained with all valves wide open. Since the minimum flow requirement for the pump is 15 gpm, this flow would not be adequate to protect the pump from damage. Without the ability to isolate the minimum flow recirculation lines or to measure flow directly, the majority of CCI pump flow cannot be measured without implementing system design modifications.

DENC proposes that during 1ST pump tests, for the quarterly Group B, and the biennial comprehensive pump test, the system will be throttled to a reference flow of 10 gpm and variance as allowed by the Code, with an unmonitored recirculation flow of approximately 15 gpm. The pump differential pressure will then be recorded and compared to the ASME Code lower required action limit changed from 10% to 6% for both the Group B and comprehensive tests. This proposed alternative to the specific requirements of ISTB-5122 and ISTB-5123 identified above will provide a method to conservatively identify pump degradation with an acceptable level of quality and safety. NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Sections ISTB-5122 (for Group B tests) and ISTB-5123 (for comprehensive tests) require the test parameters identified in Table ISTB-3000-1 to be determined and recorded.

Additionally, Table ISTB-5121-1 provides the acceptance criteria for the test parameters identified in Table ISTB-3000-1 for Group Band comprehensive tests. The licensee has proposed an alternative in lieu of the requirements of these sections for the CCI pumps that are classified as Group B, ASME Code Class 3 pumps. The function of the CCI pumps, 3CCl*P1 A and 3CCl*P1 B, is to provide 9.5 gpm of cooling water flow to the safety injection pump lube oil cooler. CCI pump flow can only be determined on the main flow path, and approximately 15 gpm recirculation flow is unmonitored.

The minimum flow recirculation lines were not designed to allow flow measurement with either permanent or temporary instrumentation that would meet ASME Code requirements.

In the same relief request in letter dated December 27, 2007 (ADAMS Accession No. ML080020059), for the previous 1ST interval, the licensee indicated that the total length of straight pipe for the 3CCl*P1A and 3CCl*P1 B recirculation lines is approximately 28 inches and 21 inches, respectively, which is insufficient length to install flow measurement equipment.

Furthermore, installation of a blind flange to block flow in the minimum recirculation lines was considered, but would restrict flow to 11 to 12 gpm, which is not sufficient to meet the minimum 15 gpm required to prevent pump damage. Neither of the minimum flow recirculation lines were designed to be isolated.

Therefore, without the ability to isolate the minimum flow recirculation lines or to measure flow directly, the total CCI pump flow cannot be determined during pump 1ST. Compliance with the ASME OM Code requirements for total flow measurement would require major system modification, including installation of flow measuring devices and additional piping. As such, the licensee proposes, for both the quarterly Group B and biennial comprehensive tests, that the system will be throttled to a reference flow of 10 gpm (with variance as determined by the ASME OM Code) with an unmonitored recirculation flow of approximately 15 gpm. The pump differential pressure will then be recorded and compared to the required action criteria of Table ISTB-5121-1 with a lower range of 0.90 (-10 percent) revised to 0.94 (-6 percent) for both Group Band comprehensive tests. No changes are proposed for higher ranges. Since the pump head versus flow characteristics are relatively flat over the normal operating range for the affected pumps, the change in pump differential pressure from the rated flow to the shutoff head condition is approximately

3. 7 percent. As a result, a complete obstruction of recirculation flow could only increase pump differential pressure (mask pump degradation) by an amount up to 3. 7 percent. Millstone proposes to modify the lower acceptance criteria for required action from 0.90 to 0.94 to account for a complete obstruction of recirculation flow of approximately 15 gpm. For both quarterly Group B and biennial comprehensive tests, the licensee will establish 10 gpm of main flow as a reference point and utilize pump differential pressure as an alternative measure of pump degradation at the rated flow of 25 gpm. The measured differential pressure data are then co_mpared to the modified required action range criteria of 0.94, which is 4 percent more restrictive than that required by the ASME OM Code. Any increase in recirculation flow (e.g., by increase in orifice size) would result in higher total pump flow, and thereby a reduction in pump differential pressure, which would be conservatively identified as pump degradation.

Therefore, the proposed alternative will provide reasonable assurance of the operational readiness for the affected pumps, and imposing the ASME OM Code requirements would result in a hardship, without a compensating increase in the level of quality and safety. 4.2 Licensee's Alternative Request P-02 The request is proposed in accordance with 10 CFR 50.55a(z)( 1) for the duration of the fourth 10-year 1ST program interval at Millstone

3. The NRC staff notes that a similar alternative request was authorized for the third 10-year 1ST program interval at Millstone 3 in the letter dated October 24, 2008. Applicable Code Requirements ASME OM Code 2012 Edition ISTB-1400, "Owner's Responsibility," (b), states, "[The Owner's responsibility includes) identifying each pump to be tested in accordance with the rules of this Subsection, categorizing it as either a Group A or Group B pump, and listing the pumps in the plant records (see ISTB-9000).

A pump that meets both Group A and Group B definitions shall be categorized as a Group A pump." Affected Components The request applies to the Residual Heat Removal (RHR) pumps 3RHS*P1A and 3RHS*P1 B, which are Group A/B, ASME Code Class 2 pumps. Reason for Request The licensee states: Pursuant to 10 CFR 50.55a, "Codes and Standards," paragraph (z)(1), relief is requested from the requirement of ASME OM Code ISTB-1400(b).

This relief will result in testing the Residual Heat Removal pumps as Group B rather than Group A during power operations.

This proposed relief will result in a lower potential for pump degradation due to pump wear while maintaining the capability of measuring pump performance.

The basis of the relief request is that the proposed alternative would provide an acceptable level of quality and safety. The Residual Heat Removal pumps meet the categorization requirements of Group A pumps in that they are operated routinely during plant shutdowns and refueling outages. However, these pumps also meet the requirements of Group B, in that during normal operation (reactor critical) they are not operated except for testing. Proposed Alternative and Basis for Use The licensee states: DENC proposes that the Residual Heat Removal pumps (3RHS*P1A and 3RHS*P1 B) be tested as standby pumps (Group B) during power operation and as continuously operating pumps (Group A) during refueling operations.

During refueling operations, the comprehensive pump test may be substituted for a quarterly Group A test that comes due. DENC also proposes that any time a comprehensive pump test is performed; the [ASME OM] Code-required quarterly low-flow test (Group B) requirement may be deleted for that quarter. The requirements of Mandatory Appendix V, for performing a periodic verification test, will be performed each refuel outage. These pumps are centrifugal type pumps that provide the low head safety injection function during power operation and provide reactor core cooling during the cooldown phase of shutdown cooling. During normal power operations, the Residual Heat Removal pump is in a standby condition and is considered an essential part of the Emergency Core Cooling System (ECCS). Each pump starts automatically upon receipt of a safety injection signal, taking suction from the Refueling Water Storage Tank during the injection phase of an accident.

The pumps discharge to the reactor coolant system. ASME ISTB-1400(b) states that if a pump meets both Group A and Group B definitions, it shall be categorized as a Group A pump. The Residual Heat Removal pumps are currently tested during normal operation using the minimum flow recirculation loop. The design flow rate of each Residual Heat Removal pump is 4000 gpm. This flow rate can only be achieved during shutdown periods when injection into the reactor coolant system at a reduced pressure is possible.

Classifying these pumps as Group B during power operation minimizes the time required to perform quarterly testing. With minimum pump run-time requirements, and no requirements to record vibration levels, the length.of each quarterly pump test and the accompanying unavailability time for these pumps should be reduced. Since these pumps are not operated routinely during plant operation except for required surveillance testing, there is no time or wear-related degradation mechanism that would warrant performing more detailed quarterly tests on the Residual Heat Removal pumps. NUREG/CP-0137, Vol. 1, "Proceedings of the Third NRG/American Society of Mechanical Engineers (ASME) Symposium on Valve and Pump Testing," includes a report entitled, "Description of Comprehensive Pump Test Change to ASME Code, Subsection ISTB." This report details the philosophy of classifying pumps as Group A or Group B. According to the author, the intent of having different test requirements for different pump groups is to relate the requirements for the amount and degree of quarterly performance monitoring to the amount of degradation expected based on pump operation.

Testing the Residual Heat Removal pumps quarterly as Group A pumps during power operation is contrary to the philosophy of the referenced report. Quarterly Group A testing subjects these pumps to increased test requirements and performance monitoring.

Also, this testing introduces the potential for more degradation due to pump wear (caused by low-flow operation) at the time when they are standby pumps and would not otherwise be subject to operation induced degradation.

Group A testing during power operation may be more detrimental to the long-term health of these components than Group B testing. In Generic Letter (GL) 89-04, "Guidance on Developing Acceptable lnservice Testing Programs," (ADAMS Accession No. ML031150259), Position 9, the NRC determined that, in cases where flow can only be established through a non-instrumented, minimum-flow path during quarterly pump testing, and a path exists at cold shutdown or refueling outages to perform a test of the pump under full or substantial flow conditions, the increased interval for flow measurement is an acceptable alternative to the [ASME OM] Code requirements.

The proposed alternative to the specific requirements of ISTB-1400(b) identified above will provide adequate indication of pump performance and continue to provide an acceptable level of quality and safety. Therefore, pursuant to 1 O CFR 50.55a(z)( 1 ), DENC requests approval of this proposed alternative to the specific ISTB requirements identified in this request. NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Section ISTB-1400(b

), requires that pumps be categorized as either Group A or Group B pumps and requires that pumps meeting both definitions are categorized as Group A. In lieu of these requirements of ISTB-1400(b), the licensee has proposed that the RHR pumps be tested as standby pumps (Group B) during Modes 1 through 4, and as continuously operating pumps (Group A) during Modes 5 and 6. In Modes 5 and 6, the CPT may be substituted for a quarterly Group A test that comes due during a mid-cycle cold shutdown period, as provided by Subsection ISTB of the ASME OM Code. ISTB-5000 states that when a Group A test is required, a CPT may be substituted.

The licensee states that a CPT will be performed instead of a Group A test during Modes 5 and 6. ISTB-2000 defines Group A pumps as "pumps that are operated continuously or routinely during normal operation, cold shutdown, or refueling operations;" and Group B pumps as "pumps in standby systems that are not operated routinely except for testing." Based on these definitions, the RHR pumps meet the definition of Group B pumps during normal operation in Modes 1 through 4. In Modes 5 and 6, the RHR pumps are used for shutdown cooling and meet the definition of Group A pumps. ISTB-1400(b) states that "A pump that meets both Group A and Group B pump definitions shall be categorized as a Group A pump." This would normally cause the RHR pumps to be classified as Group A. However, because of the inability to achieve a substantial flow rate in Modes 1 through 4, it is not possible to conduct a Group A test that would provide very much meaningful data to detect degradation due to the relatively flat profile of the pump hydraulic curve and the higher vibration levels present at these near shutoff head flow conditions.

Additionally, the RHR pumps are standby pumps during Modes 1 through 4, and little degradation is expected with respect to hydraulic performance during the operational period when the pumps are idle. In GL 89-04, Position 9, the NRC determined that, in cases where flow can only be established through a non-instrumented, minimum flow path during quarterly pump testing, and a path exists at cold shutdown or refueling outages to perform a test of the pump under full or substantial flow conditions, the increased interval is an acceptable alternative to the ASME OM Code requirements.

The quarterly Group B test will be performed using the minimum recirculation flow path under low-flow conditions and only flow will be measured.

Additionally, during Modes 5 and 6 (during refueling outages and cold shutdowns), a CPT will be performed instead of a Group A test. Millstone 3 TS SR 4.5.2, f requires verification that each RHR pump's developed head at the test flow point is greater than or equal to the required developed head in accordance with the frequency established by the 1ST program. This TS requirement will be performed at the frequency required by the modified 1ST program. The proposed alternative testing of the RHR pumps as Group B during Modes 1 through 4, and as Group A during Modes 5 and 6, is consistent with GL 89-04, Position 9, and provides reasonable assurance of operational readiness of the RHR pumps. Therefore, the NRC staff finds that the proposed alternative will provide an acceptable level of quality and safety. The licensee referenced a paper titled "Description of Comprehensive Pump Test Change to ASME OM Code, Subsection ISTB" that is included in NUREG/CP-0137, Volume 1. This NUREG is a compilation of papers presented at an NRC/ASME Symposium on Valve and Pump Testing. The NRC staff notes that statements and opinions advanced in the papers presented at the symposium are individual expressions of the authors and not those of either ASME or the NRC. 4.3 Licensee's Alternative Request P-03 The request is proposed in accordance with 10 CFR 50.55a(z)( 1) for the duration of the fourth 10-year 1ST program interval at Millstone

3. Applicable Code Requirements ASME OM Code 2012 Edition ISTB-3300, "Reference Values," (a), states, "Initial reference values shall be determined from the results of testing meeting the requirements of paragraph ISTB-3100, Preservice Testing, or from the results of the first inservice test." ISTB-3300, "Reference Values," (b), states, "New or additional reference values shall be established as required by paragraph ISTB-3310 or ISTB-3320, or subparagraph ISTB-6200(c)." ISTB-3300, "Reference Values," (f), states, "All subsequent test results shall be compared to these initial reference values or to new reference values established in accordance with paragraph ISTB-3310 or ISTB-3320, or subparagraph ISTB-6200(c)." ISTB-5121, "Group A Test Procedure," (e}, and ISTB-5123, "Comprehensive Test Procedure," ( e ), state, "All deviations from the reference values shall be compared with the ranges of Table ISTB-5121-1, and corrective action taken as specified in paragraph ISTB-6200.

Vibration measurements shall be compared to both the relative and absolute criteria shown in the alert and required action ranges of Table ISTB-5121-1.

For example, if vibration exceeds either 6Vr or 0.7 in/sec (1.7 centimeters/second (cm/s), the pump is in the required action range." ISTB-5221, "Group A Test Procedure," (e}, and ISTB-5223, "Comprehensive Test Procedure," ( e ), state, "All deviations from the reference values shall be compared with the ranges of Table ISTB-5121-1, and corrective action taken as specified in paragraph ISTB-6200.

Vibration measurements shall be compared to both the relative and absolute criteria shown in the alert and required action ranges of Table ISTB-5121-1.

For example, if vibration exceeds either 6Vr or 0.7 in/sec (1.7 cm/s), the pump is in the required action range." Affected Components The request applies to smooth running pumps in the 1ST program. In response to RAI 3P-03-1 in letter dated July 19, 2018 (ADAMS Accession No. ML 18205A 176), the licensee provided the following table of affected pumps that have at least one vibration reference value less than 0.05 ips. Pump ID Pump Name ASME Pump Code Group Class 3CCE*P1A Charging Pump Seal Cooling Pump, P1A 3 A 3CCE*P1B Charging Pump Seal Cooling Pump, P1 B 3 A 3CCl*P1A Safety Injection Cooling Pump, P1A 3 B 3CCl*P1J3 Safety Injection Cooling Pump, P1 B 3 B 3CCP*P1A Reactor Plant Component Cooling Pump, P1 A 3 A 3CCP*P1B Reactor Plant Component Cooling Pump, P1 B 3 A 3CCP*P1C Reactor Plant Component Cooling Pump, P1 C 3 A 3CHS*P2A Boric Acid Transfer Pump, P2A 3 A 3CHS*P2B Boric Acid Transfer Pump, P2B 3 A 3CHS*P3A Chemical Volume Control Charging Pump, P3A 2 A 3CHS*P3B Chemical Volume Control Charging Pump, P3B 2 A 3CHS*P3C Chemical Volume Control Charging Pump, P3C 2 A 3EGF*P1A 'A' Emergency Gen Fuel Oil Transfer Pump, P1A 3 B 3EGF*P1B 'B' Emergency Gen Fuel Oil Transfer Pump, P1 B 3 B 3EGF*P1C 'A' Emergency Gen Fuel Oil Transfer Pump, P1 C 3 B 3EGF*P1D 'B' Emergency Gen Fuel Oil Transfer Pump, P1 D 3 B 3FWA*P1A Motor Driven Steam Generator Aux Feedwater Pump, P1 A 3 B 3FWA*P1B Motor Driven Steam Generator Aux Feedwater Pump, P1 B 3 B 3FWA*P2 Turbine Aux Feedwater Pump, P2 3 B 3HVK*P1A Control Building Chill Water Pump, P1A 3 A 3HVK*P1B Control Building Chill Water Pump, P1 B 3 A 3QSS*P3A Quench Spray Pump, P1A 2 B 3QSS*P3B Quench Spray Pump, P1 B 2 B 3RHS*P1A Residual Heat Removal Pump, P1A 2 A 3RHS*P1B Residual Heat Removal Pump, P1 B 2 A 3SFC*P1A Fuel Pool Cooling Pump, P1A 3 A 3SIH*P1A Safety Injection Pump, P1A 3SIH*P1B Safety Injection Pump, P1 B 3SWP*P1A Service Water Pump, P1A 3SWP*P2A Control Building Air Cond Booster Pump, P2A 3SWP*P2B Control Building Air Cond Booster Pump, P2B 3SWP*P3A MCC and Rod Control Area Air Cond Booster Pump, P3A 3SWP*P3B MCC and Rod Control Area Air Cond Booster Pump, P3B Reason for Request The licensee states: 2 2 3 3 3 3 3 Pumps with vibration reference value (Vr) < 0.05 ips are identified as smooth running pumps. Each smooth running pump has at least one Vr that is currently less than 0.05 ips. Small values for Vr produce small acceptable ranges for pump operation.

The acceptable ranges are defined in Tables ISTB-5121-1, ISTB-5221-1, ISTB-5321-1, and ISTB-5321-2 as less than or equal to 2.5Vr. Based on the small acceptable range, a smooth running pump could be subject to unnecessary increased testing if the measured vibration parameter exceeds this acceptable range. For very small reference values, hydraulic noise and instrument error can be a significant portion of the reading and affect the repeatability of subsequent measurements.

Also, operating experience from the Millstone Power Station Predictive Maintenance Program has shown that changes in vibration levels in the range of 0.05 ips do not normally indicate significant degradation in pump performance.

It should be noted that all of the pumps in the 1ST Program will remain in the Predictive Maintenance Program. This alternative to the requirements of ISTB-3300, ISTB-5100, ISTB-5200, ISTB-5300 and the associated tables provides an acceptable level of quality and safety.

Proposed Alternative and Basis for Use The licensee states: To avoid unnecessary increased testing, a minimum value for Vr of 0.05 ips has been proposed for velocity measurements.

This minimum value will be applied to individual vibration locations for certain pumps whose measured reference value is less than 0.05 ips. When new reference values are established per ISTB-3310, ISTB-3320 or ISTB-6200(c), the measured parameters will be evaluated for each location to determine if the provisions of this relief request still apply. In addition to the requirements of ISTB, the pumps in the ASME lnservice Testing Program are included in the Millstone Predictive Maintenance Program. The Millstone Predictive Maintenance Program currently employs predictive monitoring techniques such as: B B A A A B B

• Vibration monitoring and analysis beyond that required by ISTB,

• Oil sampling and analysis where applicable (e.g., for pumps with sufficiently large oil reservoirs).

If the measured parameters are outside the normal operating range or are determined by analysis to be trending toward an unacceptable degraded state, appropriate actions are taken that may include:

• Increased monitoring to establish rate of change,

• Review of component specific information to identify cause, or

• Removal of the pump from service to perform maintenance.

For the smooth running pumps, if a measured reference value is below 0.05 ips for a particular vibration measurement location, then subsequent test results for that location may be compared to an acceptable range based on 0.05 ips. In addition to the Code requirements, the pumps in the 1ST Program are included in and will remain in the Millstone Predictive Maintenance Program even if certain pumps have very low vibration readings and are considered to be smooth running pumps. This proposed alternative to the requirements of ISTB-3300, ISTB-5100, ISTB-5200, ISTB-5300, and the associated tables will provide adequate indication of pump performance and continue to provide an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(z)(1

), this proposed alternative requests relief from the specific ISTB requirements identified in this request. NRC Staff Evaluation The 2012 Edition of the ASME OM Code requires that the vibration of all safety-related pumps be measured; ISTB-3540 describes the measurements to be taken. These measurements are required to be compared with the vibration acceptance criteria specified in Tables ISTB-5121-1, ISTB-5221-1, ISTB-5321-1, and ISTB-5321-2 for centrifugal, vertical line shaft centrifugal, positive displacement, and reciprocating positive displacement pumps, respectively, to determine if the measured values are acceptable.

Table ISTB-5121-1 shows that, if during an inservice test, a vibration measurement on a centrifugal pump exceeds 2.5 times the reference value (Vr) previously established as required by ISTB-3300, the pump is considered to be in the alert range. The frequency of testing is then doubled in accordance with 1STB-6200(a) until the cause of the deviation is determined, the condition is corrected, and the vibration level returns below the alert range, or an analysis of the pump is performed in accordance with 1STB-6200(c).

Per 1STB-6200(b), if pump vibration is found to be greater than 6 times Vr, then the pump is considered to be in the required action range and must be declared inoperable until either the cause of the deviation has been determined and the condition is corrected, or an analysis of the pump is performed in accordance with 1STB-6200(c).

Per 1STB-3300(c), the vibration reference values shall be established only when the pump is known to be operating acceptably.

For pumps whose absolute magnitude of vibration is an order of magnitude below the absolute vibration limits of the acceptance criteria, a relatively small increase in vibration magnitude may cause a pump to enter the alert or required action range, even though the pump is operating acceptably.

The pump may enter these ranges due to variations in flow, instrument accuracies, or other noise sources that would not be associated with degradation of the pump. Pumps that operate with these low vibrations are typically referred to as "smooth running." Since the acceptable range for a "smooth running" pump is so small, the pump could be subjected to unnecessary corrective action due to entry into the alert or action ranges. The NRC has previously authorized a minimum vibration level of 0.05 ips for "smooth running" pumps at several nuclear plants. However, experience has shown that only monitoring the vibration of "smooth running" pumps has not been sufficient for determining pump degradation.

At one particular plant, the NRC authorized a minimum reference value of 0.1 ips. A pump bearing at this plant experienced a significant degradation, even though the pump vibration levels were below the minimum reference value in the approved alternative.

The bearing degradation was discovered during predictive maintenance program activities.

The licensee's alternative combines a minimum vibration value of 0.05 ips for "smooth running" pumps with additional monitoring using a predictive maintenance program that includes vibration monitoring and analysis beyond that required by ASME OM Code, as well as oil sampling and analysis where applicable.

The licensee notes in its alternative request that if any of the measured parameters, including predictive maintenance values, are outside of the normal operating range or are determined by analysis to be trending towards an unacceptable degraded state, appropriate actions will be taken. These actions include increased monitoring to establish a rate of change, review of component-specific information to identify the cause of the condition, and removal of the pump from service to perform maintenance.

The proposed alternative is consistent with the objectives of the 1ST, which is to monitor degradation in safety-related components.

Based on the minimum vibration reference value of 0.05 ips noted in this request and the proposed predictive maintenance program, the NRC staff finds that the alert and required action limits specified in the request should address previously undetected pump problems and provide an adequate indication of pump performance.

The licensee's predictive maintenance program is designed to detect problems involving unacceptable mechanical conditions in advance of when a smooth running pump may reach the overall vibration alert or action limits. Therefore, the NRC staff finds that the proposed alternative will provide an acceptable level of quality and safety. 4.4 Licensee's Alternative Request P-04 The request is proposed in accordance with 10 CFR 50.55a(z)( 1) for the duration of the fourth 10-year 1ST program interval at Millstone

3. Applicable Code Requirements ASME OM Code 2012 Edition ISTB-5121, "Group A Test Procedure," and ISTB-5123, "Comprehensive Test Procedure," for centrifugal pumps that require adjustment to a specific reference value. ISTA-3130, "Application of Code Cases," (b), states, "Code Cases shall be applicable to the edition and addenda specified in the test plan." Affected Components The request applies to the Reactor Building Closed Cooling Water pumps 3CCP*P1A, 3CCP*P1 B, and 3CCP*P1 C, which are Group A, ASME Code Class 3 pumps. Reason for Request The licensee states: DENC proposes to use Code Case OMN-16 to allow the use of a pump reference curve during testing rather than a single data point. This Code Case has been approved for use. However, applicability of this code case extends only to the 2011 Addenda of the OM Code. Proposed Alternative and Basis for Use The licensee states: DENC proposes to use Code Case OMN-16 as written in the 2012 Edition of the OM Code, and supplemented with Figure 1 of OMN-16 in the 2006 Addendum of the OM Code. The component cooling (CC) pumps provide cooling flow for heat removal capabilities for the Nuclear Steam Supply System (NSSS) supplied equipment and Balance of Plant (BOP) equipment.

Two CC pumps are required to be operable in Modes 1 through 4. Testing of the third pump requires manipulation of two trains of CC to balance flow rates and reduce the chance of lifting a pressure relief valve. Pursuant to 10 CFR 50.55a(z)( 1 ), DENC requests approval of the use of OMN-16, Revision 1, as stated in Table 2 of Regulatory Guide 1.192, Revision 2. Code Case OMN-16 has been approved by Reg. Guide 1.192, Revision 2 and therefore, provides an acceptable level of quality and safety. NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Sections ISTB-5121 and ISTB-5123, require centrifugal pumps to be adjusted to a specific reference value for testing. Section ISTA-3130(b) states that Code Cases shall be applicable to the ASME OM Code edition and addenda specified in the test plan. The licensee has proposed an alternative test in lieu of the requirements of these paragraphs for Reactor Building Closed Cooling Water pumps. Specifically, the licensee proposes to apply ASME OM Code Case OMN-16 to the 2012 Edition of the ASME OM Code to allow the use of a pump reference curve during testing instead of using a single data point. As discussed in ASME OM Code Case OMN-16, when testing a centrifugal pump where adjusting the pump to a specific reference value is impractical, the establishment of additional pump curves for reference flow rates, differential pressures, and vibration is acceptable.

Application of ASME OM Code Cases is addressed in 10 CFR 50.55a(b)(6) through references to RG 1.192, Revision 2, which list acceptable and conditionally acceptable Code Cases for implementation in the 1ST program and snubber program. RG 1.192, Revision 2, Table 2, shows that Code Case OMN-16, Revision 1, is conditionally approved, provided it is supplemented with Figure 1 of the 2006 Addenda. Code Case OMN-16, Revision 1, was published with the 2012 Edition of the ASME OM Code, and it is.applicable to the 1995 Edition through the 2011 Addenda of the ASME OM Code. There is no technical reason for prohibiting the use of Code Case OMN-16, Revision 1, with the 2012 Edition of the ASME OM Code. Further, NRC staff reviewed the 2012 Edition of the ASME OM Code and Code Case OMN-16, Revision 1, and confirmed that there are no changes in the applicable Code sections referenced within the Code Case OMN-16, Revision 1. Therefore, the NRC staff concludes that the licensee's proposed alternative provides an acceptable level of quality and safety. 4.5 Licensee's Alternative Request P-05 By the letter dated August 6, 2018, the licensee withdrew pump alternative request P-05. 4.6 Licensee's Alternative Request S-01 The request is proposed in accordance with 10 CFR 50.55a(z)(1) for the duration of the fourth 10-year 1ST program interval at Millstone

3. Applicable Code Requirements ASME OM Code 2012 Edition ISTD-4252, "Subsequent Examination Intervals," (c), states, "The duration of examination intervals following the completion of the second refueling outage shall be in accordance with Table ISTD-4252-1." ISTA-3130, "Application of Code Cases," (b), states, "Code Cases shall be applicable to the edition and addenda specified in the test plan." Affected Components The request applies to all hydraulic and mechanical snubbers in scope of the 1ST program. Reason for Request The licensee states: Pursuant to 1 O CFR 50.55a, "Codes and Standards," paragraph (z)(1 ), relief is requested from the applicability statement in Revision 2 of Code Case OMN-13 as shown in the 2012 Edition of the ASME OM Code. This request is to allow the use of ASME Code Case OMN-13, Revision 2 with the 2012 Edition of the ASME OM Code. Code Case OMN-13, Revision 2 provides alternative rules for establishing the intervals for the visual examination of snubbers.

Code Case OMN-13, Revision 2 applies to the 1995 Edition through the 2011 Addenda. DENC will implement the 2012 Edition of the ASME OM Code for the fourth 10 year 1ST interval.

Proposed Alternative and Basis for Use The licensee states: By using Code Case OMN-13, Revision 2, DENC will be able to alter the visual examination intervals currently required by paragraph ISTD-4252(c) of the 2012 Edition of the ASME OM Code. ISTD-4252(c) currently requires that snubbers be visually examined in accordance with Table ISTD-4252-1 of the ASME OM Code, which states that each snubber within the scope of paragraph ISTA-1100 must be visually examined on a frequency not to exceed 48 months. Revision 2 of Code Case OMN-13 permits the user to extend that visual examination frequency to once each ten year interval.

This permission is based on the provisions that the licensee must perform the visual examinations under the code case using the same criterion that would have been used under the Code and, in addition, the following criteria specified in the code case shall also be met: 1. Examination for indications of degradation or severe operating environments

2. Examination prior to maintenance or testing 3. Monitoring of reservoir fluid level 4. Review of Operational Readiness test data 5. Examination during disassembly

6. Transient dynamic event evaluation

7. Corrective action on unacceptable snubbers Based on the additional criteria listed above and the provisions that the original visual examination parameters specified in the 2012 Edition of the ASME OM Code will also be met, the use of Code Case OMN-13, Revision 2, approved by the NRC in Reg. Guide 1.192, will provide at least equivalent assurance that snubbers remain visually acceptable for performing their safety functions.

This proposed alternative to the specific requirements of ISTD-4252(c) identified above will provide adequate visual indication of snubber performance and continue to provide an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(z)(1

), DENC requests approval of this proposed alternative to the specific ISTD requirements identified in this request. NRC Staff Evaluation The 2012 Edition of the ASME OM Code, Section ISTD-4252(c), requires snubber examination intervals following the second refueling outage to be in accordance with intervals specified in Table ISTD-4252-1.

The snubber visual examination interval can be extended up to 48 months by meeting the requirements as specified in Table ISTD-4252-1 and its notes. Section ISTA-3130(b) states that Code Cases shall be applicable to the ASME OM Code edition and addenda specified in the test plan. The licensee has proposed an alternative to the requirements of ISTD-4252(c) and ISTA-3130(b) for all snubbers in the 1ST program. Specifically, the licensee proposes to use ASME OM Code Case OMN-13, Revision 2, which allows extension of the visual examination interval beyond the interval allowed in Table ISTD-4252-1.

Code Case OMN-13 is applicable to the 1995 Edition through the 2011 Addenda of the ASME OM Code; therefore, the licensee has also proposed to apply Code Case OMN-13 to the 2012 Edition of the ASME OM Code as an alternative to the requirements of 1STA-3130(b).

Application of ASME OM Code Cases is addressed in 10 CFR 50.55a(b)(6) through references to RG 1.192, Revision 2, which lists acceptable and conditionally acceptable Code Cases for implementation in the 1ST program and snubber program. RG 1.192, Revision 2, shows Code Case OMN-13, Revision 2, in Table 1 as acceptable for use without conditions.

Code Case OMN-13, Revision 2, was published with the 2012 Edition of the ASME OM Code, and it is applicable to the 1995 Edition through the 2011 Addenda of the ASME OM Code. There is no technical reason for prohibiting the use of the Code Case OMN-13, Revision 2, with the 2012 Edition of the ASME OM Code. Further, the NRC staff reviewed the 2012 Edition of the ASME OM Code and Code Case OMN-13, Revision 2, and confirmed that there are no changes in the applicable Code sections referenced within Code Case OMN-13, Revision 2. Therefore, the NRC staff concludes that the licensee's proposed alternative provides an acceptable level of quality and safety.

4.0 CONCLUSION

As set forth above, the NRC staff determined that for Millstone 2 alternative requests P-01, P-02, V-01, and S-01, and for Millstone 3 alternative requests P-02, P-03, P-04, and S-01, the proposed alternatives provide an acceptable level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 1 O CFR 50.55a(z)( 1) for these requests.

Therefore, the NRC staff authorizes the use of these alternative requests for the Millstone 2 fifth 10-year 1ST program interval and for the Millstone 3 fourth 10-year 1ST program interval, which begin on December 2, 2018, and are scheduled to end on December 1, 2028. As set forth above, the NRC staff determined that for Millstone 2, alternative request V-02, and for Millstone 3, alternative request P-01, compliance with the specified requirements would result in hardship or unusual difficulty, without a compensating increase in the level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(z)(2) for these requests.

Therefore, the NRC staff authorizes the use of these alternative requests for the Millstone 2 fifth 10-year 1ST program interval, and for the Millstone 3 fourth 10-year 1ST program interval, which begin on December 2, 2018, and are scheduled to end on December 1, 2028. All other ASME OM Code requirements for which relief was not specifically requested and approved in the subject requests remain applicable.

Principal Contributor:

A. Mink Date: November 13, 2018 D. Stoddard

SUBJECT:

MILLSTONE POWER STATION, UNIT NOS. 2 AND 3-ALTERNATIVE REQUESTS RELATED TO THE FIFTH AND FOURTH 10-YEAR INTERVAL PUMP, VALVE, AND SNUBBER INSERVICE TESTING PROGRAMS, RESPECTIVELY (EPID L-2018-LLR-0012-THROUGH EPID L-2018-LLR-0022)

DATED NOVEMBER 13, 2018 DISTRIBUTION:

PUBLIC PM Reading File RidsNrrDorlLpl1 Resource RidsNrrPMMillstone Resource RidsNrrLALRonewicz Resource RidsNrrDeEmib Resource RidsACRS_MailCTR Resource RidsRgn1 MailCenter Resource AMink, NRR MFarnan, NRR JBowen, OEDO LBurkhart, OEDO CCook, OEDO ADAMS A ccess1on N ML 18290A602 o.: OFFICE DORL/LPL 1 /PM DORL/LPL 1 /LA NAME RGuzman LRonewicz DATE 10/18/2018 10/22/2018 DE/EMIB/BC*

SBailey 10/16/2018 OFFICIAL RECORD COPY *b *1 >Y e-ma1 DORL/LPL 1 /BC DORL/LPL 1/PM JDanna RGuzman 11/09/2018 11/13/2018