FLEX Implementation. Roy Harter RLH Global Services. SAMG-D course, IAEA, Vienna, Austria October

Transcription

1 FLEX Implementation Roy Harter RLH Global Services SAMG-D course, IAEA, Vienna, Austria October 2015

2 What is FLEX? US Nuclear Industry Response to NRC Mitigating Strategies Order EA , Order Modifying Licenses with Regard to Requirements for Mitigation Strategies for Beyond-Design-Basis External Events Approach is outlined in NEI 12-06, Rev 1 Provides a diverse and flexible means to prevent fuel damage while maintaining containment function in beyond design basis external event conditions resulting in an: Extended Loss of AC Power, and Loss of Normal Access to the Ultimate Heat Sink Objective: Establish an essentially indefinite coping capability by relying upon installed equipment, onsite portable equipment, and pre-staged offsite resources 2 2

3 3 FLEX Objectives

4 Diverse & Flexible Coping Capability (FLEX) Emergency Plans Emergency Response Prevention of Fuel Damage Emergency Plans SAMGs SBO Coping Capability Increased Defense-in- Depth SAMGs Diverse & Flexible CopingStrategy (FLEX) SBO Coping Capability Protection of Plant Equipment Design Basis External Events Design Basis External Events Current Current plus FLEX 4

5 5 FLEX Addresses NRC Tier 1 Recommendations

6 FLEX Elements Both plant and FLEX equipment that provides means of obtaining power and water to maintain or restore key safety functions for all reactors at a site. This could include equipment such as pumps, generators, batteries and battery chargers, compressors, hoses, couplings, tools, debris clearing equipment, temporary flood protection equipment and other supporting equipment or tools. Reasonable staging and protection of FLEX equipment from BDBEEs applicable to a site. The FLEX equipment would be reasonably protected from applicable site-specific severe external events to provide reasonable assurance that N sets of FLEX equipment will remain deployable following such an event. 6

7 FLEX Elements Procedures and guidance to implement FLEX strategies. FLEX Support Guidelines (FSG), to the extent possible, will provide pre-planned FLEX strategies for accomplishing specific tasks in support of Emergency Operating Procedures (EOP) and Abnormal Operating Procedures (AOP) functions to improve the capability to cope with beyond-design-basis external events. Programmatic controls that assure the continued viability and reliability of the FLEX strategies. These controls would establish standards for quality, maintenance, testing of FLEX equipment, configuration management and periodic training of personnel. 7

8 FLEX Analysis Plant-specific analyses will determine the duration of each phase. Recovery of the damaged plant is beyond the scope of FLEX capabilities as the specific actions and capabilities will be a function of the specific condition of the plant and these conditions cannot be known in advance. To the extent practical, generic thermal hydraulic analyses will be developed to support plant-specific decision-making. Justification for the duration of each phase will address the on-site availability of equipment, the resources necessary to deploy the equipment consistent with the required timeline, anticipated site conditions following the beyond-design-basis external event, and the ability of the local infrastructure to enable delivery of equipment and resources from off-site. 8

9 9 Use MAAP to Identify Capabilities for Extended and Phase 1-2 Transition

10 Use MAAP to Identify Capabilities for Extended and Phase 1-2 Transition SBO with RCIC Operating (Torus Suction; Recirc Seal Leak 36 gpm) SRV Depressurize to 150 psig Torus water temperature exceeds 200 F HCL Exceeded; Depressurize RPV to <50 psig; RCIC Tripped Torus water temperature exceeds 230 F RPV level below TAF Core Damage PSP Exceeded Containment PCPL Torus water temperature exceeds 260 F Result: Adequate Core Cooling 6.0 Hours Aggressive Cooldown to 150 psig at <100 F/hr t (Hours) 10

11 Use MAAP to Identify Capabilities for Extended and Phase 1-2 Transition SBO with RCIC Operating (Torus Suction; Recirc Seal Leak 36 gpm) SRV Depressurize to 150 psig HCL Exceeded Torus water temperature exceeds 200 F All Alignments of Portable D/G to Battery Chargers & Portable Diesel Fire Pump Completed Torus water temperature exceeds 230 F PSP Exceeded Torus water temperature exceeds 260 F Containment PCPL Result: Adequate Core Cooling >24 Hours RCIC operable for 6.2 hours DC battery life extended to 7 hours based on load shed Portable equipment aligned by 6.2 hours Aggressive Cooldown to 150 psig at <100 F/hr t (Hours) 11

12 FLEX Boundary Conditions Beyond-design-basis external event occurs impacting all units at site. All reactors on-site initially operating at power, unless site has procedural direction to shut down due to the impending event. Each reactor is successfully shut down when required (i.e., all rods inserted, no ATWS). On-site staff is at site administrative minimum shift staffing levels. No independent, concurrent events, e.g., no active security threat. All personnel on-site are available to support site response. Spent fuel in dry storage is outside the scope of FLEX. 12

13 Site Staffing Challenges On-shift personnel resource planning is limited to the minimum complement described in the site Emergency Plan. This staffing level is the minimum on-shift complement, such as present during a backshift, weekend or holiday. Sites are to perform staffing assessments to include the consideration that the on-shift personnel assigned emergency plan implementation functions are not assigned responsibilities that would prevent the timely performance of their assigned functions as specified in the emergency plan. The staffing assessment should also consider the applicable actions from the Station Blackout (SBO) coping strategies. 13

14 Site Access Challenges (NEI-12-01) First 6 hours No site access. This duration reflects the time necessary to clear roadway obstructions, use different travel routes, mobilize alternate transportation capabilities (e.g., private resource providers or public sector support), etc hours Limited site access. Individuals may access the site by walking, personal vehicle or via alternate transportation capabilities (e.g., private resource providers or public sector support). 24+ hours Improved site access. Site access is restored to a near-normal status and/or augmented transportation resources are available to deliver equipment, supplies and large numbers of personnel. 14

15 15 FLEX Assessment Process

16 16 FLEX Assessment Process

17 17 BWR Baseline Coping Summary

18 18 PWR Baseline Coping Summary

19 19 Establishing Event Response Sequence

20 20 Establishing Event Response Sequence

21 Instrumentation Assessment Actions specified in plant procedures/guidance for loss of ac power are predicated on use of instrumentation and controls powered by station batteries. In order to extend battery life, a minimum set of parameters necessary to support strategy implementation should be defined. The parameters selected must be able to demonstrate the success of the strategies at maintaining the key safety functions as well as indicate imminent or actual core damage to facilitate a decision to manage the response to the event within the Emergency Operating Procedures and FLEX Support Guidelines or within the SAMGs. Typically, these parameters would include the following: 21

22 FLEX Mitigation Strategies FLEX employs a three phase approach: Phase 1 - Initially cope by relying on installed plant equipment, Phase 2 - Transition from installed plant equipment to onsite FLEX equipment, Phase 3 - Obtain additional capability and redundancy from offsite equipment until power, water, and coolant injection systems are restored or commissioned. Diverse and flexible to enable deployment of the strategies for a range of initiating events and plant conditions 22

23 Representative High-level Example (BWR) 1. Phase 1 Initial Coping Capability Use RCIC for RPV makeup from suppression pool Rely on DC Power for key instrumentation and controls 2. Phase 2 Extended Coping Capability Charge battery to maintain DC power Use Reliable Hardened Vent for containment heat removal Provide extended RPV makeup with portable pump 1. Phase 3 Extended Coping Capability Use additional offsite equipment from Regional Response Center 23

24 Representative High-level Example (PWR) Phase 1 Initial Coping Capability Turbine-driven AFW for SG makeup from Condensate Storage Tank Rely on DC Power for key instrumentation and controls Phase 2 Extended Coping Capability Charge battery to maintain DC power Provide extended SG makeup with portable pump Provide RCS makeup with portable pump, as needed Phase 3 Extended Coping Capability Use additional offsite equipment from Regional Response Center 24

25 FLEX Communications Assessment Guidance provided in NEI 12-01, Section 4 Phase 1 assess capabilities for all specified EP functions except FLEX Phase 2 assess capabilities for FLEX Should have methods and capabilities necessary to support simultaneous implementation of any 2 FLEX strategies for each affected unit 25

26 SAFER (Phase 3) Organization and Response Plan

27 SAFER Organization SAFER Strategic Alliance for FLEX Emergency Response SAFER is an alliance established between AREVA and Pooled Inventory Management (PIM). The SAFER team is contracted by the nuclear industry to establish and operate National SAFER Response Centers (NSRCs) to purchase, store, maintain and deliver emergency response equipment in the case of a major nuclear accident or BDBEE in the US. An effective response is dependent on integrated planning and response actions among the nuclear station, SAFER team, governmental authorities and industry & vendor support personnel. 27

28 SAFER Facilities Primary and Alternate Facilities Two Facilities in Case One is Rendered Out of Service by an Event SAFER Control Centers & National SAFER Response Centers 28

29 SAFER Facilities National SAFER Response Centers (NSRC) Storage and Deployment of Equipment up to 4 Units Duplicate Equipment at Each Response Center Preventive Maintenance and Testing Performed at NSRCs Two Locations Memphis, TN Phoenix, AZ Staffing NSRC is Manned to Perform Maintenance / Testing Activated by the SAFER Control Center (SCC) to Support Deployment 29

30 30 Staging Areas (Selected by the site)

31 Staging Areas Staging Areas Staging Areas Are Determined by the Utility (illustrated in the next slide) Staging Area A Final Resting (Operational) Place(s) of equipment on-site Staging Area B Staging Area on-site (preferred if NSRC trucks can directly access the site) Staging Area C Primary off-site Staging Area ~= 25 Miles From the Site Staging Area D Optional Off-site Staging Area ~= 25 Miles From the Site 31

32 SAFER Staging Area Sizing Study (~360 x 250 ) The helicopter area may be preferred to be a safe distance from personnel or staging area operations 32

33 Equipment - Generic Equipment Performance Characteristics # of Units Medium Voltage Generator 4160 V 1 MW 18 Low Voltage Generator 480 V 1100 kw 10 High Pressure Injection Pump 2000 psi 60 gpm 10 SG/RPV Makeup Pump 500 psi 500 gpm 10 Low Pressure / Medium Flow Pump 300 psi 2500 gpm 10 Low Pressure / High Flow Pump 150 psi 5000 gpm 10 Lighting Towers 440,000 lumens (minimum) 30 Diesel Fuel Transfer 500 gallon air-lift container 10 Diesel Fuel Transfer Tank 264 gallon tank, with mounted 10 AC/DC pumps Portable Fuel Transfer Pump 60 gpm after filtration 10 33

34 Equipment Non Generic (1/2) Equipment Medium Voltage Generator in Excess of 2 MW 480/600V Step Up Transformer Quantity Purchased 1 Reactor Units Using Equipment for Coping Reactor Units Using Equipment for Defense in Depth 2 NOTES The generic and non-generic 4160V generators are the same in terms of accounting for the total number of 4160V generators needed by a site. Some units may use up to 2 (1 from each NSRC) additional generators (in addition to the generic 4160V generators) for defense in depth. Credit is taken for the generic maintenance spare Coping Strategy - Catawba 1 & 2. No allowance for maintenance unavailability is necessary. Each NSRC is capable of supporting 4 reactor units for coping or defense-in-depth, as applicable. Air Compressor 10 ~ ~ Purchased per NSRC (same as Generic Equipment) Water Treatment 4 4 (2 sites) 59 (34 sites) Coping Strategy - Byron 1 & 2 and Braidwood 1 & 2. One water treatment system is capable of providing the water necessary for each site for coping. (90 day Out-Of-Service time applies) 34

35 Equipment Non Generic (2/2) Equipment Portable Submersible Pump Quantity Purchased 1 Reactor Units Using Equipment for Coping Reactor Units Using Equipment for Defense in Depth 2 NOTES Initially thought to be required for some, this equipment was procured and only a small amount retained (2 at each NSRC) for defense-in-depth. Water Storage No allowance for maintenance unavailability is necessary because maintenance is limited to visual inspection for age-related degradation. Each NSRC is capable of supporting 4 reactor units as defensein-depth. Mobile Boration System 10 ~ ~ Purchased per NSRC (same as Generic Equipment) Ventilation Fan 10 ~ ~ Purchased per NSRC (same as Generic Equipment) Suction Lift Booster Pump 14 ~ ~ A 2 reactor unit site utilizes 3 booster pumps (5000 gpm each): 1 booster pump per 5000 gpm generic pump (2) and shares a single booster pump between both 2500 gpm generic pumps. 2 sites utilize spare per NSRC. 35

36 SAFER Response Plans Site-Specific SAFER Response Plan Chapters 1.Introduction 2.SAFER Control Center 3.National SAFER Response Center 4.Logistics & Transportation 5.Staging Area 6.Site Interface Procedure 7.Equipment Listing Addendum A SAFER Contact list Addendum B Vendor Contact list Addendum C State Contact List Addendum D Event Log Form 36

37 37 Defense-In-Depth for Extreme External Events

38 38 Defense-In-Depth for Extreme External Events