ML20048A019
| ML20048A019 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 02/11/2020 |
| From: | Mark D. Sartain Dominion Energy Nuclear Connecticut |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 20-033 | |
| Download: ML20048A019 (8) | |
Text
Dominion Energy Nuclear Connecticut, Inc.
5000 Dominion Boulevard, Glen Allen, VA 23060 DominionEnergy.com February 11, 2020 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 DOMINION ENERGY NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNIT 2
Dominion
=---' Energy Serial No.
NRA/SS Docket No.
License No.20-033 RO 50-336 DPR-65 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION FOR LICENSE AMENDMENT REQUEST TO REVISE TS 3.8.1.1, "A.C. SOURCES - OPERATING,"
TO SUPPORT MAINTENANCE AND REPLACEMENT OF THE MILLSTONE UNIT 3
'A' RESERVE STATION SERVICE TRANSFORMER AND 345 KV SOUTH BUS SWITCHYARD COMPONENTS By letter dated August 17, 2019 (ADAMS Accession No. ML19234A111), and supplemented by letter dated October 22, 2019 (ADAMS Accession No. ML19304A294), Dominion Energy Nuclear Connecticut, Inc. (DENC) submitted a license amendment request (LAR) to revise Millstone Power Station Unit 2 (MPS2)
Technical Specifications (TS). The LAR proposes to revise TS 3.8.1.1, "A.C. Sources -
Operating," to add a new Required Action a.3, that provides an option to extend the allowed outage time (AOT) from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 10 days for one inoperable offsite circuit.
The LAR also proposes a one-time allowance to the new proposed Required Action a.3 that extends the AOT to 35 days for one inoperable offsite circuit. This one-time allowance is needed for replacement of the Millstone Power Station Unit 3 (MPS3) 'A' reserve station service transformer, its associated equipment, and other 345 kV south bus switchyard components that are nearing the end of their dependable service life.
In an email dated December 30, 2019, the NRC issued a draft request for additional information (RAI) related to the proposed changes to TS 3.8.1.1. A conference call was subsequently held with the NRC on January 16, 2020 to provide clarification of the draft RAI question. DENC agreed to respond to the RAI by February 24, 2020. In an email dated January 23, 2020, the NRC transmitted the final version of the RAI. provides DENC's response to the RAI. Attachment 2 contains a revised marked-up TS page.
Serial No: 20-033 Docket No. 50-336 Page 2 of 3 Should you have any questions in regard to this submittal, please contact Shayan Sinha at (804) 273-4687.
Sincerely,
CtvL Mark D. Sartain Vice President - Nuclear Engineering & Fleet Support COMMONWEAL TH OF VIRGINIA COUNTY OF HENRICO The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by Mark D. Sartain, who is Vice President - Nuclear Engineering and Fleet Support of Dominion Energy Nuclear Connecticut, Inc. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that Company, and that the statements in the document are true to the best of his knowledge and belief.
Acknowledged before me this //-f/, day of hbl"c..7, 2020.
My Commission Expires: ay.) Y-b -r 3 \\, Z.. O °2.3.
GARY DON MILLER Notary Public Commonwealth of Virginia Reg. # 7629412 My Commission Expires August 3*;, 20,Y Attachments:
1.
Response to Request for Additional Information for License Amendment Request to Revise TS 3.8.1.1, "A.C. Sources - Operating," to Support Maintenance and Replacement of the Millstone Unit 3 'A' Reserve Station Service Transformer and 345 KV South Bus Switchyard Components 2.
Revised Marked-Up Technical Specifications Page Commitments made in this letter: None
cc:
U.S. Nuclear Regulatory Commission Region I 2100 Renaissance Blvd, Suite 100 King of Prussia, PA 19406-2713 R. V. Guzman Senior Project Manager - Millstone Power Station U.S. Nuclear Regulatory Commission One White Flint North 11555 Rockville Pike Mail Stop 08 C2 Rockville, MD 20852-2738 NRG Senior Resident Inspector Millstone Power Station Director, Radiation Division Department of Energy and Environmental Protection 79 Elm Street Hartford, CT 06106-5127 Serial No: 20-033 Docket No. 50-336 Page 3 of 3
ATTACHMENT 1 Serial No.20-033 Docket No. 50-336 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION FOR LICENSE AMENDMENT REQUEST TO REVISE TS 3.8.1.1, "A.C. SOURCES - OPERATING,"
TO SUPPORT MAINTENANCE AND REPLACEMENT OF THE MILLSTONE UNIT 3
'A' RESERVE STATION SERVICE TRANSFORMER AND 345 KV SOUTH BUS SWITCHYARD COMPONENTS DOMINION ENERGY NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNIT 2
Serial No.20-033 Docket No. 50-336, Page 1 of 2 By letter dated August 17, 2019 (ADAMS Accession No. ML19234A111 ), and supplemented by letter dated October 22, 2019 (ADAMS Accession No. ML19304A294), Dominion Energy Nuclear Connecticut, Inc. (DENC) submitted a license amendment request (LAR) to revise Millstone Power Station Unit 2 (MPS2) Technical Specifications (TS). The LAR proposes to revise TS 3.8.1.1, "AC. Sources - Operating," to add a new Required Action a.3, that provides an option to extend the allowed outage time (AOT) from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 10 days for one inoperable offsite circuit. The LAR also proposes a one-time allowance to the new proposed Required Action a.3 that extends the AOT to 35 days for one inoperable offsite circuit. This one-time allowance is needed for replacement of the Millstone Power Station Unit 3 (MPS3)
'A' reserve station service transformer (RSST), its associated equipment, and other 345 kV south bus switchyard components that are nearing the end of their dependable service life.
In email dated December 30, 2019, the Nuclear Regulatory Commission (NRC) transmitted a request for additional information (RAI) related to the LAR. DENC agreed to respond to the RAI by February 24, 2020. In email dated January 23, 2020, the NRC transmitted the final version of the RAI. This attachment provides DENC's response to the RAI.
Proposed TS 3.8.1.1 In letter dated August 14, 2019, the following change was proposed for TS 3.8.1.1 (added text is italicized and balded).
Inoperable Equipment Required ACTION a.
One offsite a.1 Perform Surveillance Requirement 4.8.1.1.1 for remaining offsite circuit circuit within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> prior to or after entering this condition, and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter.
AND a.2 Restore the inoperable offsite circuit to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> (within 10 days if Required ACTION a.3 is met) or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
AND a.3 With the MPS3 'A' RSST inoperable and the MPS3 'A' NSST energized with breaker 15G-13T-2 {13T} and associated disconnect switches closed, restore either of/site circuit to OPERABLE status within 10 days* if the following requirements are met:
Within 30 days prior to entering the 10-day AOT, the availability of the supplemental power source shall be verified.
During the 10-day AOT, the availability of the supplemental power source shall be checked once per shift. If the supplemental power source becomes unavailable at any time during the 10-day AOT, restore to available status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
To facilitate replacement of the MPS3 'A' RSST and associated equipment, use of a one-time 35-day allowed outage time is permitted provided the requirements of Required ACTION a.3 are met. The work shall be completed no later than the end of MPS3 Refueling Outage 22 (fall 2023}.
Request for Additional Information #1 (Proposed TS 3.8.1.1)
Serial No.20-033 Docket No. 50-336, Page 2 of 2 Required Action a.2 has an added parenthetical statement (within 10 days if Required Action a.3 is met) which allows an extension of the AOT from 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to 10-days. New Required Action a.3 requires restoration of either offsite circuit to operable status within 10-days and the 10-day AOT has an associated footnote denoted by*. Footnote
- allows the 10-day AOT to be extended to 35-days, one time only, to facility replacement of the MPS3 'A' RSST and associated equipment provided the requirements of Required Action a.3 are met.
Required Action a.3 allows the 10-day AOT to be extended via footnote *; however, Required Action a.2 does not allow the 10-day AOT to be extended because footnote* is not applied to the 10-day AOT referenced in Required Action a.2. TS 3.8.1.1 as currently proposed, does not allow use of the one-time AOT extension to 35-days in footnote
- because Required Actions a.2 and a.3 conflict with each other. In addition, it is not clear that the supplemental power source requirements in Required Action a.3 applies when the AOT is extended to 35-days via footnote*.
Provide a resolution to the conflict between Required Actions a.2 and a.3 in TS 3.8.1.1 and provide clarity in TS 3.8.1.1 Required Action a.3 that the supplemental power source requirements apply when the AOT is extended to 35-days via footnote*.
DENC Response DENG agrees with the staff's observation regarding the conflict between Required Actions a.2 and a.3 as it pertains to the applicability of the one-time use of the 35-day AOT. To resolve this conflict, DENG will revise the proposed TS markup to add an asterisk to each reference to the 10-day AOT in TS 3.8.1.1.a. This change will provide clarification that the one-time 35-day AOT (denoted by an asterisk and footnoted) applies to both Required Actions a.2 and a.3 and that the supplemental power source requirements specified in Required Action a.3 also apply when the AOT is extended to 35-days.
Please note that the proposed TS 3.8.1.1 markup shown above in NRG's RAI was subsequently revised in DENG's LAR supplement dated October 22, 2019. Therefore, the revisions to the proposed TS markup provided in Attachment 2 are based on the October 22, 2020 proposed TS markup.
ATTACHMENT 2 Serial No.20-033 Docket No. 50-336 REVISED MARKED-UP TECHNICAL SPECIFICATIONS PAGE DOMINION ENERGY NUCLEAR CONNECTICUT, INC.
MILLSTONE POWER STATION UNIT 2
AND a.3 Serial No.20-033 Docket No. 50-336, Page 1 of 1 3/4.8 ELECTRICAL POWER SYSTEMS 3/4.8.1 A.C. SOURCES OPERATING LIMITING CONDITION FOR OPERATION 3.8.1.1 As a minimum, the following A.C. electrical power sources shall be OPERABLE:
a.
Two physically independent circuits between the offsite transmission network and the onsite Class lE distribution system, and b.
Two separate and independent diesel generators each with a separate fuel oil supply tank containing a minimum of 12,000 gallons of fuel.
APPLICABILITY:
MODES 1, 2, 3 and 4.
ACTION:
Inoperable Equipment Required ACTION
- a.
One offsite a.l Perform Surveillance Requirement 4.8.1.1.1 for circuit remaining offsite circuit within 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> prior to or after entering this condition, and at least once per 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> thereafter.
(within 1 0 days* if Required AND ACTION a.3 is met) a.2 Restore the inoperable site circuit to OPERABLE status within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
.f' With MPS3 in MODE 5, 6, or defueled, the MPS3 'A' RSST inoperable, and the MPS3 'A' NSSTenergized with breaker 15G-13T-2 (13T) and associated disconnect switches closed, restore either offsite circuit to OPERABLE status within 10 days* if the following requirements are met:
- Within 30 days prior to entering the 10-day*AOT, the availability of the supplemental power source (MPS3 SBO diesel generator) shall be veried.
- During the 10-day*AOT, the availability of the supplemental power source shall be checked once per shift. If the supplemental power source becomes unavailable at any time during the 10-day*AOT, restore to available status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or be in HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and COLD SHUTDOWN within the following 30 hours3.472222e-4 days <br />0.00833 hours <br />4.960317e-5 weeks <br />1.1415e-5 months <br />.
- The risk management actions contained in DENC letter 19-282B, Attachment 4 (also provided in TS Bases 3/4.8), shall remain in effect during the 10-day* AOT.
r To facilÚate replacement of the MPS3 "A' RSST and associated equipment, use of a one-lime 35-day allowed outage time is pennitted provided the requirements al l
Required ACTION a.3 are met. The work shall be completed no later than the end of MPS3 RefiJeing outage 22 (fan 2023).
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