ML13079A321
| ML13079A321 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 03/11/2013 |
| From: | Gillespie T Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| Download: ML13079A321 (7) | |
Text
A Duke T.
PRESTON GILLESPIE, Jr.
Duke Vice President 1E4 nergy Oconee Nuclear Station Duke Energy ON01 VP / 7800 Rochester Hwy.
Seneca, SC 29672 864-873-4478 864-873-4208 fax March 11, 2013 T. Gillespie@duke-energy. com U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001
Subject:
Duke Energy Carolinas, LLC (Duke Energy)
Oconee Nuclear Station (ONS), Units 1, 2, and 3 Docket Number 50-269, 50-270, and 50-287 Interim Milestones for National Fire Protection Association (NFPA) 805 Compliance and Associated Compensatory Measures On March 5, 2013, a pre-decisional enforcement conference (PEC) Was held between Duke Energy personnel and United States Nuclear Regulatory Commission (NRC) staff. This letter is supplementing information provided at the PEC and contains additional details associated with compensatory measures and scheduled implementation milestones.
Compensatory Measures As a part of the plan for transition to NFPA 805, transition license conditions were put into the Facility Operating License for all three ONS units. These conditions, in part, require ONS to maintain appropriate compensatory measures in place until specified modifications are complete. As a result, the required compensatory measures were implemented and will be maintained until the specified modifications are completed.
ONS has also implemented additional compensatory measures to recover a portion of the risk benefit that remains unrealized until the Protected Service Water (PSW) system is implemented.
These additional compensatory measures enhance the site's ability to mitigate events, reduce the fire exposure risk, and improve overall plant risk when the Standby Shutdown Facility (SSF) is not available for extended periods. ONS is committed to the compensatory measures as delineated in Attachment 1 until the risk offsets of completing Milestone 5 in Attachment 2 are achieved.
Implementation Milestones ONS is committed to the milestone schedule provided in Attachment 2 which charts installation of specified risk beneficial PSW equipment. Capabilities that result in quantitative risk improvements are achieved at Milestones 1 and 5. Milestones 2, 3, and 4 are established to monitor project implementation progress and represent additional equipment that could be available to mitigate the effects of fire. Completion of Milestone 6 achieves compliance with the NFPA 805 current license basis.
www.duke-energy.com rn
NFPA 805 Interim Milestones March 11, 2013 Page 2 The final completion date of November 15, 2016, is provided with the following drivers factored into the schedule development:
" Completion of engineering and procurement activities associated with the Auxiliary Building and Reactor Building ventilation and cooling modifications
- Completion of implementation work associated with the Auxiliary Building and Reactor Building ventilation and cooling modifications
- Resolution of vendor quality issues
" Completion of required licensing work
" Coordination of activities requiring ONS and/or Keowee Hydro Unit outages
- Completion of the engineering reviews of the modification close out packages, as-built drawing packages, and final Probabilistic Risk Analysis (PRA) modeling with the as-built configurations
- Recognition of the potential for additional discovery issues
" Recognition of potential schedule impacts due to on-line/outage risk interactions with existing safety-significant systems undergoing maintenance during PSW system implementation activities ONS considers the request for additional time to implement the PSW system to be prudent based on a number of considerations. The additional time is needed to complete the detailed engineering work to provide the Auxiliary Building and Reactor Building cooling system changes needed to address the added heat load from the PSW equipment. Such detailed, high quality, engineering work minimizes construction and licensing rework, thereby ensuring the PSW system's risk benefits are attained in a timely manner. Time is also needed to perform a thorough evaluation and resolution of vendor quality issues and implement the actions to ensure the PSW safety related equipment will meet or exceed its required performance specifications, thus preserving nuclear safety. Taken together, the detailed design work, completion of the required licensing work, and resolution of the vendor quality issues assure the PSW system is installed with quality and will perform its safety function with certainty in the unlikely event it is called upon. In addition, the challenges in installing this complex safety system require attention to detail and thorough planning to achieve the appropriate sequencing and integration into future plant and system outages. The time utilized to complete the detailed planning will ensure this integration takes place such that existing safety systems are not adversely impacted.
The additional time to complete the PSW system is warranted to achieve the risk benefits that this system provides. ONS understands the importance of completing the PSW system implementation in a timely manner. The new system provides risk reductions and tangible benefits associated with mitigating the effects of fires as well as other event initiators. In addition, implementation of the PSW system is credited with providing risk offsets allowing transition to NFPA 805.
ONS has taken prudent steps to reduce the fire hazard risk to ensure Oconee remains safe until compliance with the license condition is achieved. Oconee has implemented and continues to maintain the compensatory measures specified in the NFPA 805 license amendment. Safety is further enhanced through the additional compensatory measures that will remain in place to promote improved fire prevention, suppression, and mitigation until the PSW system is installed (i.e. Milestone 5). Implementation of NFPA 805 has already yielded fire safety benefits through
NFPA 805 Interim Milestones March 11, 2013 Page 3 improved control of transient combustibles, implementation of modifications for fire area separation associated with blockhouses and breaker coordination, and implementation of improved requirements for establishing fire watches. ONS has recently completed the installation of low leakage Reactor Coolant Pump (RCP) seals for all three units. The risk benefit from low leakage RCP seals was not available to credit at the time that the NFPA 805 license amendment was approved. However, the completion of the seal modifications provides Important fire risk benefits In addition to the PSW system. Additionally, Milestone I describes the capability to provide commercial power to the SSF through the PSW building which provides further benefits and will be available on or before October 1, 2013. Therefore, the Implementation of compensatory measures, the benefits already gained through Implementation of NFPA-805, and the benefit realized by the RCP seal upgrades provide measurable plant risk improvements during the interim time period while the PSW system is being completed.
ONS will complete the NFPA 805 conversion according to the following milestones. Additional details are located In Attachment 2:
- 1. Provide commercial power path to the SSF by October 1, 2013
- 2. Provide equipment for the power path from Keowee to PSW by July 18, 2014
- 3. Provide equipment for the power path from PSW to HPI system by October 1. 2014
- 4. Provide equipment to align the PSW pump to the steam generators by June 3, 2015
- 5. PSW System complete by February 4, 2016
- 6. Satisfy the requirements of NFPA 805 by November 15, 2016 This letter contains the following commitments:
- 1. Duke Energy commits to the compensatory measures described in Attachment 1 until the risk offsets of completing Milestone 5 in Attachment 2 are achieved.
2-Duke Energy commits to the milestones as delineated in Attachment 2.
Inquiries on the contents of this letter should be directed to Kent Alter, ONS Regulatory Affairs Group, at (864) 873-3255.
Sincerely, T. Preston Gillespie, Jr., Vice President, Oconee Nuclear Station Attachments:
- 1. Compensatory Measures to Manage Fire Risk
- 2. Milestone Schedule
NFPA 805 Interim Milestones March 11, 2013 Page 4 cc:
Mr. Victor McCree Regional Administrator U.S. Nuclear Regulatory Commission - Region II Atlanta Federal Center 61 Forsyth St., SW, Suite 23T85 Atlanta, Georgia 30303 Mr. John P. Boska, Project Manager (ONS)
(By electronic mail only)
U. S. Nuclear Regulatory Commission One White Flint North, M/S O-8G9A 11555 Rockville Pike Rockville, MD 20852 Mr. Ed Crowe NRC Senior Resident Inspector Oconee Nuclear Station
NFPA 805 Interim Milestones March 11, 2013, Page 1 ATTACHMENT I - COMPENSATORY MEASURES TO MANAGE FIRE RISK In addition to compensatory measures required by License Condition D, Fire Protection, Transition License Condition 3, Oconee Nuclear Station has implemented the following compensatory measures to reduce the potential fire related risk through rigorous prevention, and enhanced suppression and mitigation capabilities. These actions are prudent risk reduction measures beyond the required compensatory measures. They are grouped below in the three main areas of the fire protection program's defense in depth philosophy.
Prevention:
Require fire protection engineer approval of hot work in High Safety Significant (HSS) fire zones Increased priority for repair of newly identified hydrogen or oil leaks and non-functional fire protection features to ensure such vulnerabilities are promptly addressed Suppression Capability:
Maintaining per shift fire brigade staffing at 10 which is twice that required by NFPA 805
" The Fire Brigade Response Procedure (AP/O/AN1700/043) has been revised to incorporate guidance to utilize a pre-staged diesel driven pump to charge the High Pressure Service Water (HPSW) system if HPSW pumps are out of service (QOS) or fail.
Mitigation:
Oconee has established a response strategy for fire induced station blackout that uses either existing Auxiliary Service Water (ASW) pump or a pre-staged diesel driven portable pump to feed a steam generator for each unit to provide reactor cooling. This action will be fully implemented in March 2013, when operator training on the new procedural guidance is complete. Timely implementation of this strategy relies on the additional on-shift operators that are in place for periods of SSF unavailability as described below.
During periods of time when planned SSF unavailability will exceed 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, the following additional actions will be implemented as part of the planned unavailability. For emergent SSF unavailability, efforts to implement these actions will begin as soon as practical:
o Additional operators will be added to each shifts staffing to provide resources for the prompt initiation of steam generator feed using the staged portable diesel driven pump o The HPSW pumps and breakers, ASW switchgear, and the alternate units' Emergency Feedwater supply valves will be protected per the Protected Equipment Program
" Thermal imaging scans will be performed of risk significant 4KV main feeder bus duct sections o No hot work will be allowed in HSS zones without both the Fire Protection Engineer and Operations Shift Manager approval o Maximize the readiness of the portable pump for steam generator feed by making up all but three of the hose connections (two at Auxiliary building rollup door and one at the physical connection to the existing ASW piping). Note: An alternate strategy may be implemented during the period from removal of the ASW pump and installation of PSW
NFPA 805 Interim Milestones March 11, 2013, Page 1 ATTACHMENT 2 - MILESTONE SCHEDULE In addition to the two PSW project milestones (Milestones 1 and 6 in the table below) provided at the March 5, 2013 meeting, Milestones 2, 3, 4 and 5 below are provided to allow the NRC the ability to monitor Duke Energy's progress in completing the NFPA 805/PSW project in a safe and orderly manner.
Milestone Milestone Completion Name Milestone Description Date 1
PSW Power PSW power to the Standby Shutdown Facility (SSF) October 1, 2013 to the SSF will provide the following:
from Commercial power source to the PSW Commercial Switchgear Offsite 0
Power path from the PSW Switchgear to the Power SSF Ability to align the PSW power path to the SSF as required from the SSF control room 2
PSW Power PSW power from the Keowee Hydro Station (KHS)
July 18, 2014 from will provide equipment for:
Keowee 0
Keowee power path to the PSW switchgear Hydro 0
Power path from the PSW switchgear to the Station SSF Installed 0
Equipment to align Keowee power to the SSF from the PSW switchgear 3
PSW Power PSW power to the High Pressure Injection (HPI)
October 1, 2014 to High System will provide equipment for:
Pressure 0
PSW power path to each units A&B HPI Injection pumps 1,2 System 0
Equipment to start/stop the selected HPI pump Installed from the associated Oconee control room PSW power path to the associated valves for each unit o
HP-26 (RCS Inlet Valve) o HP-24 (BWST Suction Valve) o HP-139and HP-140 (RCP Seal Flow Valves)
RC-1 55, RC-1 56, RC-157 and RC-158 (Steam Generator Vent Valves) o RC-159 and RC-160 (RV Head Vent Valves) 0 Equipment to select the HP-24, HP-26, and RCS Vent Valves power source (normal station power or PSW power) from the associated Oconee control room 1 Note: The ability to start/stop the HPI Pump from the Control Room is limited to the period of time that control power is available from the station batteries until PSW installation is complete.
2 PSW is capable of simultaneously powering one HPI pump on each unit. The HPI pump to be powered (A or B) is manually aligned in the Auxiliary Building.
NFPA 805 Interim Milestones March 11, 2013, Page 2 Milestone Milestone Completion Name Milestone Description Date 4
PSW Pump PSW pump installed will provide equipment for:
June 3, 20153 Installed PSW powered PSW pumps and flow path for providing water to each unit's SG Equipment to start/stop the PSW pump from the Oconee Unit 2 control room PSW power path to the associated valves required to establish a flow path from CCW to the SGs:
o PSW-6 (Isolation valve) o PSW-23 and PSW-25 (Flow Control Bypass Valves) o PSW-14(Shared, Mini-flow Recirculation Valve) o PSW-22 and PSW-24 (Flow Control Valves)
Equipment to align a flow path from the CCW system through the PSW pumps to the SGs from the associated Oconee control room 5
PSW PSW system completion provides the following:
February 4, 2016 System PSW power to station vital DC battery chargers Complete providing DC power to controls and instrumentation to allow system control and monitoring from the control room for an extended period of time PSW power to 400 kW of pressurizer heaters for each unit Ability to select pressurizer heater power source (normal station power or PSW power) from the Auxiliary Building Auxiliary Building and Reactor Building equipment environments suitable for equipment operation Ability to control and monitor HPI, PSW and SG heat Removal from the associated Oconee control rooms 4
6 NFPA 805 Completion of all remaining support activities and November 15, Compliance documentation including items 23, 32, and 43 from 2016 table 2.9-1 "Implementation Items" of the December 29, 2010 Oconee NFPA 805 Safety Evaluation Report 3 Installation of the PSW pump requires completion of the NRC Safety Evaluation Report (SER) associated with the PSW UFSAR and Technical Specification changes that were included in the High Energy Line Break (HELB) License Amendment Request as transmitted to the NRC on December 16, 2011. This SER is needed by August 1, 2013 to meet the schedule for this and subsequent milestones.
4 Operating procedures and operator training/qualification associated with the implementation of the PSW engineering changes are governed by the Duke Energy Engineering Change processes and the Quality Assurance Program. These activities will be completed prior to turnover of the associated structures, systems or components for use.