ML14163A586

Relief from the Inservice Testing Requirements of American Society of Mechanical Engineers Code for Operation and Maintenance of Nuclear Power Plants

ML14163A586
Person / Time
Site:	Millstone
Issue date:	07/10/2014
From:	Benjamin Beasley Plant Licensing Branch 1
To:	Heacock D Dominion Nuclear Connecticut
Thadani M
References
TAC MF2439, TAC MF2440
Download: ML14163A586 (8)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 July 10, 2014 Mr. David A. Heacock President and Chief Nuclear Officer Dominion Nuclear Connecticut, Inc.

lnnsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711

SUBJECT:

MILLSTONE POWER STATION, UNIT NOS. 2 AND 3- RELIEF FROM THE INSERVICE TESTING REQUIREMENTS OF AMERICAN SOCIETY OF MECHANICAL ENGINEERS CODE FOR OPERATION AND MAINTENANCE OF NUCLEAR POWER PLANTS (TAC NO. MF2439 AND MF2440)

Dear Mr. Heacock:

By letter dated July 8, 2013 (Agencywide Document Access and Management System Accession No. ML13197A219), Dominion Nuclear Connecticut, Inc. (DNC, the licensee) submitted alternative request G-001 to the Nuclear Regulatory Commission (NRC). The licensee proposed the use of an alternative to certain American Society of Mechanical Engineers Boiler and Pressure Vessel (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code) for the lnservice Test (1ST) Program at Millstone Power Station Units 2 and 3 (MPS2 and MPS3) for the fourth and third 10-year 1ST program intervals, respectively.

Specifically, pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR) Part 50, Section 50.55a(a)(3)(ii), the licensee requested to use the proposed alternative in G-001 on the basis that the ASME OM Code requirements present an undue hardship without a compensating increase in the level of quality or safety.

The NRC staff has reviewed the subject request and concludes, as set forth in the enclosed safety evaluation, that for alternative request G-001, the proposed alternative provides reasonable assurance that the affected components are operationally ready. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(ii), and is in compliance with the ASME OM Code requirements. All other ASME OM Code requirements for which relief was not specifically requested and approved in the subject request remain applicable. Therefore, the NRC staff authorizes alternative request G-001 at MPS2 and MPS3 for their remainder of the fourth and third 10-year 1ST program intervals, respectively, which are scheduled to end on December 1, 2018.

D. Heacock If you have any questions, please contact, Mohan Thadani, Senior Project Manager assigned to Millstone Power Station, at (301) 415-1476.

Sincerely, Benjamin Beasley, Chief Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-336 and 50-423

Enclosure:

As stated cc w/encl: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REQUEST NO. G-001 RELATED TO THE INSERVICE TESTING PROGRAM FOR THE UNIT 2 FOURTH AND UNIT 3 THIRD 10-YEAR INTERVALS DOMINION NUCLEAR CONNECTICUT, INC.

MILLSTONE POWER STATION, UNIT NOS. 2 & 3 DOCKET NOS. 50-336 & 50-423

1.0 INTRODUCTION

By letter dated July 8, 2013 (Agencywide Document Access and Management System (ADAMS) Accession No. ML13197A219), Dominion Nuclear Connecticut, Inc. (DNC), the licensee, submitted alternative request G-001 to the U.S. Nuclear Regulatory Commission (NRC). The licensee proposed alternatives to certain inservice testing (1ST) requirements of the American Society of Mechanical Engineers (ASME) Code for Operation and Maintenance of Nuclear Power Plants (OM Code) for the 1ST Program at Millstone Power Station Units 2 and 3 (MPS2 and MPS3) for the fourth and third 10-year 1ST program intervals, respectively.

Specifically, pursuant to Title 10 of the Code of Federal Regulations (1 0 CFR) Part 50, Section 50.55a(a)(3)(ii), the licensee requested to use the proposed alternative in G-001 on the basis that the ASME OM Code requirements present an undue hardship without a compensating increase in the level of quality or safety.

2.0 REGULATORY EVALUATION

Paragraph 10 CFR 50.55a(f), "lnservice 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.

Paragraph 10 CFR 50.55a(a)(3), states, in part, that alternatives to the requirements of paragraph (f) of 10 CFR 50.55a may be authorized by the NRC if the licensee demonstrates that: (i) the proposed alternative provides an acceptable level of quality and safety, or (ii) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

The MPS2 fourth ten-year 1ST interval and the MPS3 third ten-year 1ST interval both began on December 2, 2008 and are currently scheduled to end on December 1, 2018. Both 1ST programs comply with the ASME OM Code, 2001 Edition through OMb-2003 Addenda.

Based on the above, and subject to the NRC's findings with respect to authorizing the proposed alternatives to the ASME OM Code given below, the NRC staff finds that regulatory authority exists for the licensee to request and the Commission to authorize the alternatives requested by the licensee.

3.0 TECHNICAL EVALUATION

3.1 Licensee's Alternative Request G-001 This request applies to the test frequency specifications of the ASME OM Code. The frequencies for tests given in the ASME OM Code include the following, but do not include a tolerance band:

• . , >~ :* ~.*

Cod~:Paragraph .. be~ctiptiorl: .,: .*  :.

"The frequency for the inservice testing shall be in accordance with the ISTA-3120(a) requirements of Section 1ST."

ISTB-3400 Frequency of lnservice Tests ISTC-3510 Exercising Test Frequency ISTC-3540 Manual Valves ISTC-3630(a) Frequency ISTC-3700 Position Verification Testing "At least one valve from each group shall be disassembled and examined at ISTC-5221 (c)(3) each refueling outage; all valves in a group shall be disassembled and examined at least once every 8 years."

Appendix I, 1-1320 Test Frequencies, Class 1 Pressure Relief Valves Appendix I, 1-1330 Test Frequencies, Class 1 Nonreclosing Pressure Relief Devices Test Frequencies- Class 1 Pressure Relief Valves that are used for Appendix I, 1-1340 Thermal Relief Applicatio_~

Appendix I, 1-1350 Test Frequencies- Class 2 and 3 Pressure Relief Valves Appendix I, 1-1360 Test Frequencies- Class 2 and 3 Nonreclosing Pressure Relief Devices Test Frequencies- Class 2 and 3 Primary Containment Vacuum Relief Appendix 1, 1-1370 Valves Test Frequencies - Class 2 and 3 Vacuum Relief Valves Except for Primary Appendix I, 1-1380 Containment Vacuum Relief Valves Test Frequencies- Class 2 and 3 Pressure Relief Valves that are used for Appendix I, 1-1390 Thermal Relief Application Appendix II, Performance Improvement Activities Interval ll-4000(a)(1)

Appendix II, Optimization of Condition Monitoring Activities Interval ll-4000(b)(1 )(e)

Reason for Request

ASME OM Code Section 1ST establishes the inservice test frequency for all components within the scope of the Code. The frequencies (e.g., quarterly) have always been interpreted as

"nominal" frequencies (generally as defined in Table 3.2 of NUREG-1482, Revision 1[2]) and owners routinely applied the surveillance extension time period (i.e., grace period) contained in the plant Technical Specification (TS) Surveillance Requirements (SRs). The TSs typically allow for a less than or equal to 25 percent extension of the surveillance test interval to accommodate plant conditions that may not be suitable for conducting the surveillance.

(Reference MPS2 and MPS3 TS 4.0.2.) However, regulatory issues have been raised concerning the applicability of the TS grace period to ASME OM Code-required 1ST frequencies.

The lack of a tolerance band on the ASME OM Code 1ST frequencies restricts operational flexibility. There may be a conflict where 1ST could be required (i.e., the frequency could expire), but where it is not possible or it is desired that it not be performed until sometime after a plant condition or associated Limiting Condition for Operation is within its applicability.

The NRC recognized this potential issue in the TSs by allowing a frequency tolerance as described in MPS2 and MPS3 TS 4.0.2. The lack of a similar tolerance applied to the ASME OM Code testing places an unusual hardship on the plant to adequately schedule work tasks without operational flexibility.

Thus, just as with TS-required surveillance testing, some tolerance is needed to allow adjusting ASME OM Code testing intervals to suit the plant conditions and other maintenance and testing activities. This assures operational flexibility when scheduling ISTs that minimize the conflicts between the need to complete the testing and plant conditions.

3.1.4 Proposed Alternative and Basis for Use The licensee proposes to adopt ASME OM Code Case OMN-20, lnservice Test Frequency, which was published in conjunction with ASME OM Code, 2012 Edition. The purpose of this code case is to prescribe a methodology for determining acceptable tolerances for pump and valve test frequencies. The text of Code Case OMN-20 is shown below. This proposed alternative will be utilized for the remainder of the MPS2 fourth 10-year 1ST interval and the remainder of the MPS3 third 10-year 1ST interval, which both began on December 2, 2008 and are scheduled to end on December 1, 2018. This alternative will apply to the various frequency specifications of the ASME OM Code for all pumps and valves contained within the 1ST Program scope.

Code Case OMN lnservice Test Frequency Test Frequency Grace ASME OM, Division 1, Section 1ST and all earlier editions and addenda specify component test frequencies based either on elapsed time periods (e.g., quarterly, 2 yr, etc.) or the occurrence of plant conditions or events (e.g., cold shutdown, refueling outage, upon detection of a sample failure, following maintenance, etc.).

(a) Components whose test frequencies are based on elapsed time periods shall be tested at the frequencies specified in Section 1ST with a specified time period between tests as shown in Table 1. The specified time period between tests may be reduced or extended as follows:

1) For periods specified as fewer than 2 yr, the period may be extended by up to 25% for any given test.

2) For periods specified as greater than or equal to 2 yr, the period may be extended by up to 6 mo [months] for any given test.

3) All periods specified may be reduced at the discretion of the owner (i.e., there is no minimum period requirement).

Period extension is to facilitate test scheduling and considers plant operating conditions that may not be suitable for performance of the required testing (e.g., performance of the test would cause an unacceptable increase in the plant risk profile due to transient conditions or other ongoing surveillance, test, or maintenance activities). Period extensions are not intended to be used repeatedly, merely as an operational convenience to extend test intervals beyond those specified.

Period extensions may also be applied to accelerated test frequencies (e.g., pumps in alert range) and other fewer than 2-yr test frequencies not specified in Table 1.

Period extensions may not be applied to the test frequency requirements specified in Subsection ISTD, Preservice and lnservice Examination and Testing of Dynamic Restraints (Snubbers) in Light-water Reactor Nuclear Power Plants, as Subsection ISTD contains its own rules for period extensions.

Table 1 Specified Test Frequencies Frequency Specified Time Period Between Tests Quarterly 92 days (or every 3 mo)

Semiannually 184 days (or every 6 mo)

Annually 366 days (or every year) x years x calendar years where xis a whole number of years~ 2 b) Components whose test frequencies are based on the occurrence of plant conditions or events may not have their period between tests extended except as allowed by ASME OM, Division 1, Section 1ST, 2009 Edition through OMa-2011 Addenda and all earlier editions and addenda.

3.1.5 Duration of Proposed Alternative This proposed alternative will be utilized for the remainder of the MPS2 fourth 10-year 1ST interval and of the MPS3 third 10-year 1ST interval, which began on December 2, 2008 and will end on December 1, 2018.

3.2 NRC Staff Evaluation Historically, licensees have applied and the NRC staff has accepted the standard TS definitions for 1ST intervals (including allowable interval extensions) to ASME OM Code required testing.

(Reference NUREG-1482 Revision 2, Section 3.1.3). Recently, the NRC staff reconsidered the allowance of using TS testing intervals and interval extensions for 1ST not associated with TS SRs. As noted in Regulatory Issue Summary (RIS) 2012-10, "NRC Staff Position on Applying Surveillance Requirements 3.0.2 and 3.0.3 to Administrative Controls Program Tests," the NRC determined that programmatic test frequencies can't be extended in accordance with the TS SR 3.0.2. This includes all 1ST described in the ASME OM Code not specifically required by the TS SRs.

Following this development, the NRC staff sponsored and co-authored an ASME OM Code inquiry and code case to modify the ASME OM Code to include TS-Iike test interval definitions and interval extension criteria. The resultant ASME Code Case OMN-20, as shown above, was approved by the ASME Operation and Maintenance Standards Committee on February 15, 2012 with the NRC representative voting in the affirmative. ASME Code Case OMN-20 was subsequently published in conjunction with the ASME OM Code, 2012 Edition. The licensee proposes to adopt Code Case OMN-20.

Requiring the licensee to meet the ASME OM Code requirements, without an allowance for defined frequency and frequency extensions for 1ST of pumps and valves, results in a hardship without a compensating increase in the level of quality and safety. Based on the prior acceptance by the NRC staff of the similar TS test interval definitions and interval extension criteria, the staff finds that implementation of the test interval definitions and interval extension criteria contained in ASME OM Code Case OMN-20 is acceptable. Allowing usage of ASME Code Case OMN-20 provides reasonable assurance of operational readiness of pumps and valves subject to the ASME OM Code 1ST.

4.0 CONCLUSION

As set forth above, the NRC staff determines that for alternative request G-001, the proposed alternative provides reasonable assurance that the affected components are operationally ready. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(ii), and is in compliance with the ASME OM Code requirements. All other ASME OM Code requirements for which relief was not specifically requested and approved in the subject request remain applicable. Therefore, the NRC staff authorizes alternative request G-001 at MPS2 and MPS3 for their remainder of the fourth and third 10-year 1ST program intervals, respectively, which are scheduled to end on December 1, 2018.

Principal Contributors: J. Billerbeck Date: July 10, 2014

D. Heacock If you have any questions, please contact, Mohan Thadani, Senior Project Manager assigned to Millstone Power Station, at (301) 415-1476.

Sincerely, IRA!

Benjamin Beasley, Chief Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-336 and 50-423

Enclosure:

As stated cc w/encl: Distribution via Listserv DISTRIBUTION:

PUBLIC LPL 1-1 Reading File RidsNrrDorllpl1-1 RidsNrrPMMillstone RidsNrrLKGoldstein RidsAcrsAcnw_MaiiCTR RidsNrrDoriDpr RidsRgn1 MaiiCenter JBillerbeck ADAMS ACCESSION NO.: ML14163A586 OFFICE LPLI-1/PM LPLI-1/LA DE/EPNB/BC LPLI-1/BC LPLI-1/PM NAME MThadani KGoldstein Tlupold BBeasley MThadani DATE 06/27/14 06/17/14 03/13/14 7/7/14 7/10/14 OFFICIAL RECORD COPY