ML15027A144
| ML15027A144 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 02/02/2015 |
| From: | Nadiyah Morgan Plant Licensing Branch 1 |
| To: | George Gellrich Exelon Generation Co |
| Morgan N | |
| References | |
| TAC MF3388, TAC MF3389 | |
| Download: ML15027A144 (4) | |
Text
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 February 2, 2015 Mr. George H. Gellrich, Site Vice President Exelon Generation Company, LLC Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702
SUBJECT:
CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NOS. 1 AND 2-REQUEST FOR ADDITIONAL INFORMATION REGARDING ATMOSPHERIC DUMP VALVES LICENSE AMENDMENT REQUEST (TAC NOS. MF3388 AND MF3389)
Dear Mr. Gellrich:
By letter dated January 13, 2014, as supplemented by letter dated November 3, 2014, Calvert Cliffs Nuclear Power Plant, LLC submitted a license amendment request (LAR) for Calvert Cliffs Nuclear Power Plant (Calvert Cliffs), Unit Nos. 1 and 2. The proposed LAR adds Technical Specification 3.7.18, "Atmospheric Dump Valves (ADVs)."
The Nuclear Regulatory Commission (NRC) staff is reviewing the application and has determined that additional information is needed to complete its review. The specific questions are found in the enclosed request for additional information (RAI). The NRC staff is requesting a response to the RAis within 30 days of the date of this letter.
If you have any questions regarding this matter, please contact me at (301) 415-1016.
Docket Nos. 50-317 and 50-318
Enclosure:
RAI cc w/encl: Distribution via Listserv Nadiyah S. Morgan, Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
REQUEST FOR ADDITIONAL INFORMATION REGARDING ATMOSPHERIC DUMP VALVES LICENSE AMENDMENT REQUEST CALVERT CLIFFS NUCLEAR POWER PLANT, LLC CALVERT CLIFFS NUCLEAR POWER PLANT. UNIT NOS. 1 AND 2 DOCKET NOS. 50-317 AND 50-318 By letter dated January 13, 2014 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML14015A138), as supplemented by letter dated November 3, 2014 (ADAMS Accession No. ML14309A717), Calvert Cliffs Nuclear Power Plant, LLC, the licensee, submitted a license amendment request to add Technical Specification (TS) 3.7.18, "Atmospheric Dump Valves (ADVs)," for Calvert Cliffs Nuclear Power Plant, Unit Nos. 1 and 2.
By letter dated November 3, 2014, the licensee provided responses to the Nuclear Regulatory Commission (NRC) staff's request for additional information (RAI) dated September 17, 2014 (ADAMS Accession No. ML14237A069). In order to complete its review, the NRC staff needs the following additional information:
BALANCE OF PLANT (BOP) RAI-9 In parts a.1 and a.2 of its response to RAI BOP-1, the licensee stated:
A drawing of the ADV valve body has been attached for reference (Enclosure 1)
[Drawings of the ADV Valve Body, Operator]. The ADV stem travels in the downward direction, into the steam space to open the valve. The valve is equipped with a pilot to assist in initial opening.
A drawing of the ADV valve operator has been attached for reference (Enclosure 1). The ADV is an air-to-open, fail closed, valve. Air is applied to the top of the valve diaphragm in order to lower the valve stem, and open the valve.
Air acts against the large spring (item #31), compressing it, in order to open the valve. With no air on the diaphragm, the spring forces the valve shut.
A manual operator is provided with the valve. The operator forces a rod into the valve that will act to compress the spring. The manual operator does not function to close the valve. The manual operator can be inserted to open the valve, or removed to allow the valve to close.
Remote operation is the preferred method of operation; however, it is not credited in the accident analyses to mitigate the consequences of the event.
Enclosure a.2 Local (manual handwheel) operation of the valve is credited to mitigate the consequences of some events. As described in the Updated Final Safety Analysis Report (UFSAR), Section 14.15, Steam Generator Tube Rupture, this event is the most limiting event for ADV operation. In this event, the ADV does not have to be operated for up to two hours following initiation of the event.
Again, remote operation is preferred, but not required.
The NRC staff requests that the licensee provide a discussion of how the ADV manual operator with chain operator (and associated valve extension components) is designed to withstand a design bases event, including a seismic event. Also describe the safety classification of the ADV valve operator with chain operator, including such components as the reach rod linkage, gear box, shaft, and associated linkage and gear box supports.
BOP RAI-10 In part a.6 of its response to RAI BOP-1, the licensee stated:
The Completion Times were chosen to be consistent with the Completion Times in Millstone Unit 2 TS. Millstone Unit 2 is a Combustion Engineering plant with only one ADV per SG [steam generator]. Additionally, the Millstone Unit 2 TSs do not include the block valves in the TSs, even though we believe their design is virtually identical to ours.
The NRC staff requests the licensee to justify why there is not a TS surveillance for the ADV line by local manual operation, similar to the Millstone Unit 2 TS Surveillance Requirement (SR) 4.7.1.7. For example, the Millstone TS SR states to verify each atmospheric dump line by local manual operation. The proposed Calvert Cliff's TS SR 3.7.18.1 states to verify one complete cycle of each ADV. The actual accident function of the ADV is with the local manual operation via the ADV reach rod and chain operator.
February 2, 2015 Mr. George H. Gellrich, Site Vice President Exelon Generation Company, LLC Calvert Cliffs Nuclear Power Plant 1650 Calvert Cliffs Parkway Lusby, MD 20657-4702
SUBJECT:
CALVERT CLIFFS NUCLEAR POWER PLANT, UNIT NOS. 1 AND 2-REQUEST FOR ADDITIONAL INFORMATION REGARDING ATMOSPHERIC DUMP VALVES LICENSE AMENDMENT REQUEST (TAC NOS. MF3388 AND MF3389)
Dear Mr. Gellrich:
By letter dated January 13, 2014, as supplemented by letter dated November 3, 2014, Calvert Cliffs Nuclear Power Plant, LLC submitted a license amendment request (LAR) for Calvert Cliffs Nuclear Power Plant (Calvert Cliffs), Unit Nos. 1 and 2. The proposed LAR adds Technical Specification 3.7.18, "Atmospheric Dump Valves (ADVs)."
The Nuclear Regulatory Commission (NRC) staff is reviewing the application and has determined that additional information is needed to complete its review. The specific questions are found in the enclosed request for additional information (RAI). The NRC staff is requesting a response to the RAis within 30 days of the date of this letter.
If you have any questions regarding this matter, please contact me at (301) 415-1016.
Docket Nos. 50-317 and 50-318
Enclosure:
RAI cc w/encl: Distribution via Listserv DISTRIBUTION:
PUBLIC LPLI-1 RIF RidsNrrDoriDpr RidsNrrDssSbpb S. Park, NRR RidsNrrDoriLpl1-1 RidsNrrLAKGoldstein RidsRgn1 Mail Center A. Chereskin, NRR D. Palmrose, NRR ADAMS ACCESSION NO: ML15027A144 OFFICE LPLI-1/PM LPLI-1/PM NAME AChereskin NMorgan DATE 1/28/2015 1/28/2015 Sincerely, IRA/
Nadiyah S. Morgan, Project Manager Plant Licensing Branch 1-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation RidsNrrPMCalvertCiiffs RidsAcrsAcnwMaiiCenter RidsNrrDeEmcb L. Wheeler, NRR
- See dated memo LPLI-1/LA DSS/SBPB/BC KGoldstein GCasto 01/28/2015 01/14/2015*
LPLI-1/BC BBeasley 2/02/2015 OFFICIAL RECORD COPY