ML17010A104

Request for Additional Information Regarding Alternative Request RV-01 for the Fourth 10-Year Inservice Testing Intervals

ML17010A104
Person / Time
Site:	LaSalle
Issue date:	01/10/2017
From:	Bhalchandra Vaidya Plant Licensing Branch III
To:	Bryan Hanson Exelon Generation Co, Exelon Nuclear
Vaidya B
References
CAC MF8500, CAC MF8501
Download: ML17010A104 (4)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 January 10, 2017 Mr. Bryan C. Hanson Senior Vice President Exelon Generation Company, LLC President and Chief Nuclear Officer (CNO)

Exelon Nuclear 4300 Winfield Road Warrenville, IL 60555

SUBJECT:

LASALLE COUNTY STATION, UNITS 1AND2, REQUEST FOR ADDITIONAL INFORMATION REGARDING RELIEF REQUEST RV-01, UTILIZATION OF ASME CODE CASE OMN-1, "ALTERNATIVE RULES FOR PRESERVICE AND INSERVICE TESTING OF ACTIVE ELECTRIC MOTOR-OPERATED VALVE ASSEMBLIES IN LIGHT-WATER REACTOR POWER PLANTS" - PROPOSED ALTERNATIVE IN ACCORDANCE WITH 10 CFR 50.55A(Z)(1) (CAC NOS.

MF8500 AND MF8501)

Dear Mr. Hanson:

By letter dated October 17, 2016, Agencywide Documents Access and Management System (ADAMS) Accession No. ML16292A488), Exelon Generation Company, LLC (the licensee),

requested approval of alternative testing associated with the inservice testing programs fourth 10-year interval for LaSalle County Station (LSCS), Units 1 and 2. The relief request (RR) RV-01, requested utilization of American Society of Mechanical Engineers (ASME) Code Case OMN-1, "Alternative Rules for Preservice and lnservice Testing of Active Electric Motor-Operated Valve Assemblies in Light-Water Reactor Power Plants," - Proposed Alternative In Accordance with Title 10 of the Code of Federal Regulations Section 50.55a(z)(1 ).

The U.S. Nuclear Regulatory Commission staff has reviewed the RR and determined that it needs additional information to complete its review. The licensee is requested to respond to the attached request for additional information within 30 days of the date of this letter.

B. Hanson If you have any questions, please call me at 301-415-3308.

Sincerely, Bhalchandra Vaidya, Project Manager Plant Licensing Branch 111 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-373 and 50-374

Enclosures:

As stated cc w/encl: Distribution via Listserv

REQUEST FOR ADDITIONAL INFORMATION REGARDING ALTERNATIVE REQUEST RV-01 FOR THE INSERVICE TESTING PROGRAM FOURTH 10-YEAR INTERVALS EXELON GENERATION COMPANY, LLC LASALLE COUNTY STATION, UNITS 1AND2 DOCKET NOS. 50-373 AND 50-374 CAC NOS. MF8500 AND MF8501 By letter dated October 17, 2016, Agencywide Documents Access and Management System (ADAMS) Accession No. ML16292A488 Cost Activity Code (CAC) Nos. MF8500 and MF8501, Exelon Generation Company, LLC (the licensee), requested approval of alternative testing associated with the inservice testing (IST) programs fourth 10-year interval for LaSalle County Station (LSCS), Units 1 and 2. The U.S. Nuclear Regulatory Commission (NRC) staff is reviewing the submittal and has the following questions:

(1) In the proposed alternative under the section "Compliance with RG 1.192 Conditions,

Bullet 1 , LSCS explains compliance with the condition of evaluating the adequacy of the diagnostic test interval not later than 5 years or three refueling outages (whichever is longer) from initial implementation of OMN-1 is satisfied because LSCS MOV testing frequencies identified in the IST program do not exceed three refueling cycles (i.e., a nominal 6 years). The NRC staff recognizes that LSCS has a mature MOV program and that this condition has already been addressed. However, review of LSCS current IST program plan for the third intervals at LSCS, Units 1 and 2, specify that motor-operated valves (MOVs) IST test intervals are set according to Joint Owner Group and are not to exceed 10 years. Please explain what the true test intervals are for the LSCS MOV program valves.

(2) In the proposed alternative under the section "Compliance with RG 1.192 Conditions,"

Bullet 3, the statement does not address Condition 3 of the American Society of Mechanical Engineers OM Code Case OMN-1. Please explain when applying risk insights as part of the implementation of OMN-1, how MOVs are categorized according to their safety significance.

(3) LSCS proposes to not perform as-found testing in all situations. As an alternative, LSCS has proposed an alternative that uses a process which is less dependent on as-found testing. The process selects random valves under various lubrication conditions for as-tound testing and the results are used to validate degradation assumptions. Please explain how valves are selected, how many, how often, and what degradation assumptions are.

(4) LSCS alternative seems to address stem lubrication as being the only factor that can degrade. Please explain how LSCS addresses overall actuator performance, spring pack relaxation, and possible changes in packing forces.

Enclosure

ML17010A104 OFFICE DORL/LPL3/PM DORL/LPL3/LA DE/EPNB/BC DORL/LPL3/BC DORL/LPL3/PM NAME BVaidya SRohrer DAiiey DWrona BVaidya DATE 1/10/2017 1/10/2017 1/08/2017 1/10/2017 1/10/2017