Understanding Energy: Emergency Preparedness for Nuclear in the US

Transcription

1 Understanding Energy: Emergency Preparedness for Nuclear in the US Kimberly Cook, General Manager, Plant Operations Waterford 3 Nuclear Facility Novenber 16, 2011

2 Tsunami Initiates Nuclear On March 11 a magnitude 9.0 earthquake occurred off the east coast of Japan All operating nuclear power plants shut down safely An hour later a massive tsunami about 45 feet high struck the east coast Critical equipment at Fukushima Daiichi plant was destroyed Accident

3 Fukushima Daiichi Nuclear Power Plant Before the Accident Units 5, 6 Unit 2 Unit 1 Unit 3 Unit 4

4 Tsunami Damage Looking Toward the Plant

5 No Power for Cooling Systems at Fukushima Daiichi 1-4 Cooling systems eventually stopped working due to lack of off-site power and back-up power systems Fuel in reactor heated up, generating hydrogen gas Containment pressure increased Hydrogen explosions occurred in secondary containment Plant operators injected seawater into reactors to cool fuel, prevent further damage

6 Continual Recovery Efforts Continue to cool and stabilize reactors Provide long-term cooling systems Process radioactive water Conduct detailed evaluation of event Decommission Fukushima reactors

7 Examples of Differences Between U.S. and Japanese Reactor Operations United States 1. Post-Sept. 11, 2001, actions to address large fires and explosions 2. Independent regulatory agency with 4,000 employees and $1 billion budget 3. Industry organization for oversight and sharing operating experience 4. Site-specific simulator for each reactor Japan 1. No similar action taken 2. Regulator is part of Ministry of Economy, Trade and Industry 3. No similar industry organization 4. Shared simulators for multiple plants

8 U.S. Nuclear Energy Facilities: Prepared for Extreme Events Maximum credible earthquakes, floods, other natural events Total loss of power Hydrogen generated as a result of fuel damage is removed from the plant Post 9/11: response for aircraft impact, loss of large areas of the plant Industry is prepared for the unexpected, exceeds NRC requirements

9 Hurricane Katrina

10 The Destruction Was Widespread 17,000 square miles affected in Louisiana, 20,000 in Mississippi

11 and Our Largest City Flooded

12 Design All seismic category I structures, safety-related systems and components necessary for safe shutdown of the plant are located within the Nuclear Plant Island Structure (NPIS) Reinforced concrete box structure Solid exterior walls Few doors and penetrations Design provisions (waterstops, door seals, waterproofing membranes) to minimize water intrusion

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14 Waterford 3

15 Design Tsunami and Flooding Tsunami effects minor compared to hurricane surge flooding with levee failure Maximum water level from levee failure with probable maximum flood coincident with probable maximum hurricane surge at mouth of river Maximum water level of ft MSL at north wall of NPIS Designed against high water levels and wave runup to +30 ft MSL plant grade +15 ft MSL

16 Winds Design 200 mph hurricane winds 360 mph tornado winds Hurricane Betsy estimated 110 mph winds at Moisant Hurricane Katrina 125 mph winds at landfall near Buras Hurricane Gustav 115 mph winds at landfall near Cocodrie

17 Power Design Two emergency diesel generators (EDGs) each rated at 4400 KW Located on NPIS inside the flood walls Seven day fuel capacity for each EDG Fuel tanks on NPIS with same seismic, wind and flood protection Emergency fill connections for fuel tanks above +30 ft elevation to allow additions during flooding

18 Operator Training Trained in restoring and maintaining core cooling, containment integrity and Spent Fuel Pool cooling under conditions associated with explosions, large area fires, aircraft attack and/or natural disasters Severe accident management Loss of large areas of the plant Cross-connecting systems Multiple water supplies Portable diesel powered pump with hoses, fittings, etc.

19 Emergency Response Organization Policy on participation Drills - Emergency response exercises coordinated with state, local and federal officials, evaluated by the NRC and FEMA Response Times 4 response teams Drills and response capability testing

20 Prepping for the Storm Site walkdowns/preparations completed promptly Implemented hurricane response procedure Communications equipment testing St. Charles Parish communications Twice daily industry meetings Evacuations started St. Charles Parish 0900 August responders on site for Hurricane Katrina; 183 for August, 2008 Hurricane Gustav

21 Hurricane Command Center Activated Aug. 27 Day/night shifts report to stay Hurricane Command Center Response directed from Command Center and Technical Support Center Operations staff free to focus on the plant Hurricane Watch 10:00 AM Core Team onsite 5:00 PM Briefings Collateral duties Accountability Hurricane Warning 10:00 PM

22 Hurricane Command Center Moved to power block for all personnel on Aug. 28 before weather conditions deteriorated 138 personnel on site (including 2 NRC) Just-in-time loss of offsite power and shutdown training provided Plant shutdown initiated 10:59 AM before tropical storm winds Reactor and turbine offline 1:16 PM

23 Loss of Offsite Power August 29 Both emergency diesel generators started and supplied safety busses Emergency diesel generators ran until offsite power restored A Train 9/1/05 B Train 9/2/05

24 Loss of Offsite Communications Maximum winds August 30 Gusts 86 mph at 199 ft 7:20 AM 199 ft sensor lost ~ 8:00 AM Contingency measures 501 area code Nextel Additional satellite phones

25 Katrina s Unique Challenges Corporate HQ evacuated Employees homes destroyed Security threats in New Orleans Flooded gas facilities Contractors bankruptcy fears Inoculations for workforce Severe substation flooding Communications knocked out Massive scale/logistics challenge Gasoline/Diesel shortages Inaccessibility

26 Restoration Safety Trumps Speed 1.87 million total electric customers 145,000 gas customers 28,900 Distribution poles replaced 522 Transmission lines out of service 715 Substations out of service 29 fossil/1 nuclear units shut down

27 Camp Katrina at W3

28 Restart Coordinated with support from entire Entergy Fleet NRC/FEMA restart assessment teams onsite on Sept. 6 Permission for restart, Sept. 9 Reactor critical and synced to the grid on Sept. 13 Vital to the restoration

29 Final Critique Sept. 22 Event Critique Communications improvements needed Core team staffing additions Many improvements made for Hurricane Rita Preparations Plant Safety Systems and plans functioned as designed

30 U.S. Industry Taking Steps to Make Safe Nuclear Energy Facilities Safer Short Term: Verify each plant's capability to respond to major challenges, such as aircraft impacts, loss of large areas of plant due to natural events, fires or explosions Verify each plant's capability to manage loss of off-site power, to mitigate flooding and the impact of floods on systems inside and outside the plant Inspect important equipment needed to respond to extreme events Long-term action: Exhaustive analysis of Japanese accident and how reactors, systems, structures, components, fuel and operators performed Incorporate lessons learned into U.S. reactor designs and operating practices

31 QUESTIONS?