ML18277A176
| ML18277A176 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 10/04/2018 |
| From: | Richard Guzman Plant Licensing Branch 1 |
| To: | Whitlock M Dominion Energy Nuclear Connecticut |
| Guzman R | |
| References | |
| EPID: L-2018-LLA-0099 | |
| Download: ML18277A176 (4) | |
Text
From:
Guzman, Richard To:
Michael L Whitlock Cc:
"Shayan Sinha"
Subject:
Millstone Unit 3 - LAR Modifying the TSs for the Control Building Ventilation Inlet Instrumentation - REQUEST FOR ADDITIONAL INFORMATION (EPID: L-2018-LLA-0099)
Date:
Thursday, October 04, 2018 9:18:29 AM
- Michael, On September 20, 2018, the U.S. Nuclear Regulatory Commission (NRC) staff sent Dominion Energy Nuclear Connecticut, Inc. (DENC, the licensee) the subject Request for Additional Information (RAI) as a draft (via e-mail shown below). This RAI relates to the license amendment request proposing to modify the Technical Specifications (TSs) related to Control Building Ventilation for Millstone Power Station, Unit No. 3. Specifically, the proposed amendment would revise Action 18 in TS Table 3.3-3, Functional Unit. 7.e, "Control Building Inlet Ventilation Radiation," when one or both radiation monitor instrumentation channel(s) are inoperable. With one Control Building Inlet Ventilation Radiation monitor channel inoperable for greater than 7 days, or if both radiation monitor channels are inoperable, DENC proposes to revise and reformat Action 18 to allow control room operators to manually place one train of the Control Room Emergency Ventilation System in the emergency mode of operation to provide additional time to restore one channel of Control Building Inlet Ventilation Radiation monitoring to OPERABLE status.
On October 2, 2018, the NRC staff conducted a conference call with the licensee staff to clarify the request. Following the discussion, you indicated that DENC will provide a response to this RAI within 30 days of the issuance of the RAI (i.e., by November 5, 2018).
Updated below is the official (final) RAI. A publicly available version of this e-mail and RAI will be placed in the NRCs ADAMS system. Please contact me should you have any questions in regard to this request.
- Thanks, Rich
~~~~~~~~~
Rich Guzman Sr. PM, Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Office: O-9C07 l Phone: 301-415-1030 From: Guzman, Richard Sent: Thursday, September 20, 2018 10:23 AM To: 'Michael L Whitlock' <michael.l.whitlock@dominionenergy.com>
Subject:
Millstone Unit 3 - LAR Modifying the TSs for the Control Building Ventilation Inlet Instrumentation - DRAFT REQUEST FOR ADDITIONAL INFORMATION
- Michael, By letter dated April 4, 2018 (ADAMS Accession No. ML18100A055), Dominion Energy Nuclear Connecticut, Inc., submitted a license amendment request to modify Technical Specifications related to Control Building Ventilation for Millstone Power Station, Unit No. 3.
The NRC staff has determined that additional information is needed to complete its review, as described in the request for additional information (RAI) shown below. This RAI is identified as draft at this time to confirm your understanding of the information that the NRC staff needs to complete the evaluation. Please contact me if you would like to set up a conference call to clarify this request for information. I plan to send the RAI formally by 9/28.
- Thanks,
~~~~~~~~~
Rich Guzman Sr. PM, Division Operator Reactor Licensing Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Office: O-9C7 l Phone: (301) 415-1030 Richard.Guzman@nrc.gov REQUEST FOR ADDITIONAL INFORMATION LICENSE AMENDMENT REQUEST MODIFYING THE TECHNICAL SPECIFICATIONS FOR THE CONTROL BUILDING VENTILATION INLET INSTRUMENTATION MILLSTONE POWER STATION, UNIT 3 DOMINION ENERGY NUCLEAR CONNECTICUT, INC DOCKET NO. 50-423 EPID: L-2018-LLA-0099 By letter dated April 4, 2018 (Agencywide Documents Access and Management System Accession No. ML18100A055), Dominion Energy Nuclear Connecticut, Inc., (the licensee) submitted a license amendment request (LAR) to modify Technical Specifications (TSs) related to Control Building Ventilation for Millstone Power Station, Unit No. 3 (MPS3).
Specifically, the licensee proposed to revise ACTION 18 in TS Table 3.3-3, Functional Unit.
7.e, "Control Building Inlet Ventilation Radiation," to allow continued fuel handling and reactor operation with inoperable inlet radiation monitoring instrumentation provided that one train of the control room emergency ventilation system is operating in the emergency mode. The proposed TS change specifies that one train of the control room ventilation system be placed in the emergency mode of operation after 7 days if one radiation monitor channel is inoperable or immediately if both radiation monitor channels are inoperable. The NRC staff reviewed the submittal and has determined that additional information is needed in order to complete the review.
Applicable Regulatory Guidelines Guidance for staff review of TS changes contained in NUREG-0800, Standard Review Plan for the Review of Safety Analysis Reports for Nuclear Power Plants: LWR Edition,
Section 16.0, Technical Specifications, states that proposed TS revisions should conform with comparable provisions in the applicable Standard TSs to the extent possible or justify deviations. The applicable standard TS for MPS3 is NUREG 1431, Standard Technical Specifications - Westinghouse Plants, Revision 4.0.
Issue The proposed action for two inoperable control building inlet ventilation radiation monitor channels is inconsistent with the corresponding actions presented in NUREG-1431.
In Attachment 1 to the LAR, the licensee provided the following statement:
If one channel of radiation monitoring is not restored within 7 days, movement of recently irradiated fuel will be immediately suspended, if applicable, and the unit would be placed 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 in 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 />. This proposed change is consistent with the requirements of the standard TSs (i.e., TS 3.3.7.A REQUIRED ACTION B.1.1 and B.1.2) for Westinghouse plants (NUREG-1431) since it provides the actuation instrumentation function to place the unit in a conservative mode of operation and limits the time in this configuration.
However, proposed Action 18.b also provided in Attachment 1 to the LAR states:
With two Control Building Inlet Ventilation Radiation Monitor channels inoperable, immediately place one train of Control Room Emergency Ventilation System in the emergency mode of operation, declare one Control Room Emergency Ventilation System train inoperable, and comply with the ACTION requirements of Technical Specification 3.7.7. Otherwise, immediately suspend movement of recently irradiated fuel assemblies, if applicable, and 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 in 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 />.
In addition, required action d. of MPS3 TS 3.7.7, which applies during movement of recently irradiated fuel assemblies, states:
With one Control Room Emergency Air Filtration System inoperable, restore the inoperable system to OPERABLE status within 7 days. After 7 days, either initiate and maintain operation of the remaining OPERABLE Control Room Emergency Air Filtration System in the emergency mode of operation, or immediately suspend the movement of recently irradiated fuel assemblies.
Thus, under the proposed actions for two inoperable radiation monitor channels, the NRC staff concluded that these actions would permit MPS3 operators to maintain operation of one control room emergency air filtration system in the emergency mode of operation without suspending movement of irradiated fuel assemblies because the otherwise condition of proposed action 18.b would not be satisfied. The bases for the corresponding Action D.1 for NUREG-1431 Standard TS 3.7.10 states that maintaining one emergency air filtration train in operation if the inoperable train cannot be restored to OPERABLE status within the required Completion Time ensures that the remaining train is OPERABLE, that
no failures preventing automatic actuation will occur, and that any active failure would be readily detected.
Request for Additional Information Clarify the options permitted by proposed Action 18.b under the condition when neither of two inoperable control building inlet radiation monitoring channels have been returned to OPERABLE status within 7 days and movement of recently irradiated fuel assemblies is underway. If maintaining continued operation of one control room emergency air filtration system in operation remains an option, please justify continued movement of recently irradiated fuel in that state for an unlimited time period. Otherwise, please modify proposed action 18.b to require suspension of movement of recently irradiated fuel assemblies if neither inoperable control building inlet radiation monitoring channels have been returned to OPERABLE status within 7 days. Also, if proposed action 18.b continues to reference MPS3 TS 3.7.7, please use terminology consistent with the MPS3 TS 3.7.7 LCO, which requires two OPERABLE Control Room Emergency Air Filtration Systems.