ML17339A181
| ML17339A181 | |
| Person / Time | |
|---|---|
| Site: | LaSalle  |
| Issue date: | 12/07/2017 |
| From: | Kimberly Green Plant Licensing Branch III |
| To: | |
| Green K, NRR/DORL/LPLIII | |
| Shared Package | |
| ML17339A178 | List: |
| References | |
| Download: ML17339A181 (18) | |
Text
License Amendment Request for CSCS-ECW Repairs at LaSalle County Station December 7, 2017 NRC/Exelon Meeting, NRC Headquarters Guy Ford Larry Lehman Ryan Sprengel
Agenda 1
- Introductions and Opening Remarks
- Objectives
- Need for Licensing Action
- Maintenance Details
- License Amendment Request Overview
- Regulatory Evaluation
- Summary
- Schedule
Objectives 2
- Present and discuss maintenance activities and need for License Amendment Request (LAR)
- Describe key aspects of the planned LAR
- Present proposed Technical Specification (TS) changes
- Discuss and receive feedback on the key aspects and proposed changes
Need for Licensing Action
- The planned LAR is to support plant maintenance which will improve equipment reliability.
- Proposed changes will allow installation of isolation valves and proactive CSCS-ECW piping maintenance without a dual unit shutdown.
- The maintenance replaces piping that has degraded due to long term wear and corrosion. The new isolation valves will also ensure future isolation capability.
- Four outages will be utilized to align divisional work for each unit, two divisions on each of the two units:
- L2R17 (2019) - Division 2
- L1R18 (2020) - Division 1
- L2R18 (2021) - Division 1
- L1R19 (2022) - Division 2 3
Need for Licensing Action
- The proposed CSCS-ECW maintenance replaces 4 and 6 DGCW piping and installs new isolation valves. The specific pipelines are 1DG06A-4, 1DG23B-6, 2DG06A-4 and 2DG23B-6. Because the downstream side of the pipelines are not currently equipped with isolation valves, the lines will be isolated by hot tapping and installing line stops.
- CSCS-ECW is subject to the requirements of the ASME B&PV Code Section III. Because the line stops are non-Code the impacted CSCS-ECW subsystems will be declared inoperable.
- Even though inoperable, the impacted CSCS-ECW subsystems, will remain available with no impact on risk or design function (see slide 10).
- 7 days will allow sufficient time to install and test new isolation valves to provide ASME B&PV Code Section III isolation capability.
4
- Line Stop - nonconforming line-stop used to isolate branch lines and allow installation of isolation valves
- Will be designed to meet or satisfy system design requirements (e.g. pressure capacity and seismically mounted)
Maintenance Details - Line Stop (Stopple) 5
Maintenance Details - Division 1 6
Maintenance Details - Unit 1, Division 2 7
Maintenance Details - Unit 2, Division 2 8
Maintenance Details - DGCW Supported Systems
- DGCW Division 1
- Division 1 DG (Common 0)
- ECCS cubicle area coolers
- LPCS pump motor cooler
- DGCW Division 2
- Division 2 DGs (Unit 1 1A and Unit 2 2A)
- ECCS cubicle area cooler
- Redundant equipment and divisions will be protected in accordance with the LaSalle County Station risk management program 9
License Amendment Request Overview 10
- Example: Unit 2, Division 2 Outage Planned Work Affected Subsystems*
System/Equipment Remaining L2R17 2019 Replace a 70 ft section of piping 2DG06A-4 between valve 2DG007 and line 2RH83BB-24.
And Install new isolation valve in line 2DG06A-4 adjacent to line 2RH83BB-24.
2DG06A-4 is part of the U-2, Div -2 DGCW subsystem U-2, Div-2 DGCW Inoperable/available U-2, Div-2 DG 2A Inoperable/available U-2, Div-2 RHRSW Inoperable/available U-1, Div-2 DGCW Inoperable/available U-1, Div-2 DG 1A Inoperable/available U-1, Div-2 RHRSW Inoperable/available U-2, Div-1 DGCW Operable U-2, Div-1 RHRSW Operable U-0, Div-1 DG 0A Operable U-1, Div-1 DGCW Operable U-1, Div-1 RHRSW Operable
(*) Work is being performed on Unit 2, Division 2 DGCW subsystem; both units share a common Division 2 discharge line, therefore the work also affects the Unit 1, Division 2. Additional, supported systems are not included in this table.
License Amendment Request Overview 11
- Single submittal applicable to four outages:
- L2R17 (2019) - Division 2
- L1R18 (2020) - Division 1
- L2R18 (2021) - Division 1
- L1R19 (2022) - Division 2
- Proposed change to TS 3.7.2 Conditions to allow 7 days with DGCW subsystems inoperable but available
- Proposed change to TS 3.8.1 Conditions to allow 7 days with Division 2 Diesel Generators on both units inoperable but available
License Amendment Request Overview 12
- Proposed TS changes provided as handout
- TS 3.7.2 Modified Condition A
- TS 3.7.2 New Conditions B and C
- TS 3.8.1 Modified Conditions C and F
- TS 3.8.1 New Condition G
- Applicability is constrained to four upcoming outages
- During the maintenance period, additional TS Conditions may be entered, with no changes requested
- The Safety Function Determination Program (SFDP) will be applied as appropriate for supported systems with no Loss of Safety Function
Regulatory Evaluation 13
- Regulatory requirements:
- 10 CFR 50.36 Technical Specifications
- 10 CFR 50 Appendix A, General Design Criteria
- Licensing Basis
- Precedent Amendments
- LaSalle County Station 75/161, 180/167
- Braidwood Station 30
- Byron Station 136
Summary
- EGC is planning to submit a LAR to support plant maintenance which will improve equipment reliability.
- The LAR will propose changes which would revise TS 3.7.2 and 3.8.1 to allow 7 days with one or more DGCW trains inoperable and two Division 2 DGs inoperable, during four upcoming refueling outages
- Additional system inoperability will be evaluated using the Safety Function Determination Program and will follow existing TS LCOs
- Discussion and feedback is requested on the key aspects and proposed changes 14
Schedule for Submittal
- EGC plans to submit the license amendment request in January 2018 15
Questions?
16
Acronym Key ASME B&PV Code - American Society of Mechanical Engineers Boiler and Pressure Vessel Code CFR - Code of Federal Regulations CSCS-ECW - Core Standby Cooling System - Equipment Cooling Water DG - Diesel Generator DGCW - Diesel Generator Cooling Water EGC - Exelon Generation Company LCO - Limiting Condition for Operation NRC - U.S. Nuclear Regulatory Commission RHR - Residual Heat Removal RHRSW - Residual Heat Removal Service Water TS - Technical Specification UFSAR - Updated Final Safety Analysis Report 17