NURIS 2015 1st INRAG Conference on Nuclear Risk Vienna, Austria True Lessons Learned from Fukushima Accident to be Shared Internationally April 16, 2015 Satoshi Sato Tokyo, Japan ssato@orion.ocn.ne.jp TEPCO Fukushima Daiichi Administration Office, Immediately After Earthquake. 2 TEPCO Fukushima Daini NPP In The Middle Of Tsunami 3 Fukushima Daiichi Unit 1 At The Moment of Hydrogen Explosion 4 Evacuation Of Children 5 Evacuation From A Hospital 6 Rescued Dogs 7 Evacuee Reception Center 8 Evacuee Reception Center 9 Nuclear, The Energy for The Bright Future Hungry Dogs Wondering 10 Around Evacuated Town Radioactive Plume Pathways Prepared by Prof. Hayakawa, Gunma Univ. 11 Anti-Nuclear Campaign In Tokyo 12 Blocked Access To Restricted Zone 13 Typical Evacuee Camp 14 Politicians In Evacuee Camp During Election Campaign 15 Temporarily Accumulated Radioactive Waste In Plastic Bags 16 Hidden Facts Behind Official Statements Official Statements: • Tsunami Caused Accident. • No Earthquake Damage With Any SafetyRelated Component Has Been Confirmed. • All Residents Evacuated With No Acute Radiological Effect. These statements are not wrong, but might have capped many important facts that should have attracted more attentions… 17 Man-made Accident • Improper Design Bases and Siting Criteria Earthquake, Tsunami Groundwater Level, Population Distribution • Hidden Design Flaws Physical Separation for Fire/Flood Protection Single Failure Vulnerability Fail-Safe Design Principle Significant Deviations From Original Guidelines • Unlearned Lessons Three Mile Island Chernobyl 18 Fukushima Daiichi Unit 3 Turbine Bldg. Basement M/C (A) P/C (A) M/C (C) XFMR 6900V/480V P/C (B) P/C (C) 22m P/C (D) M/C (B) M/C (D) 34m 19 SBO • LOOP • Loss of EDGs • Loss of DC Power • Loss of UPS • All simultaneously! 480VAC Power Center EDG-1B LP FDW Heaters Tb. Lub Oil Reservoir Battery Room Rx. Feedwater Pumps 125VDC Recharger A B C UPS Panel 125VDC MCC for MOVs 24VDC 125VDC Recharger Dist. Pnl. EDG-1A Fukushima Daiichi Unit 1 Tb. Bldg. & Control Bldg. Basement – Equipment Layout A B 20 Earthquake Damages/Impacts • Loss of off-site power due to isolated on-site transformers tripped by Sudden Pressure Relays. • Severely damaged LP Turbine rotors, fortunately resulting no turbine-missile accident. • Cracked on-site roads prohibited/delayed deployment of a firetruck. • Frequent/prolonged aftershocks interrupted emergency responses. • Many fine cracks on Reactor/Turbine Bldgs. allowing ground water seepage at 400 tons per day. 21 Unsafe/Struggled Evacuation Unexpected heavy traffic jam: • No traffic information available to guide safe evacuation. • Sharp edged cracks resulted in burst tires, abandoned cars along narrow dark crooked roads. • Drivers fear shortage of gas, forming long waiting lines to gas stations where only manual pumps are available due to power outage. • 3 large hospitals with 700 patients within 5km radius. 22 23 Apr. 21, 2011 Some Potentially Important Facts with Less or No Attention Paid • Dynamic Effect of Tsunami Inconsistent Behavior. Not Just Flooding. Significant Dynamic Impacts. Unprotected Discharge Outlet Directly Hit. Breakwater Not Effective. Many Manhole Covers Blown Into Air, Leaving Dangerous Pitfalls. Potential Hydrodynamic Impact to Other Equipment Not Assessed. (Main Condenser, Rad-waste Systems) • Hydrogen Explosions Not Just On The Refueling Floors. More Leak-paths. More Vulnerable. 24 Before Tsunami At The Moment Of Tsunami H = V2/(2g) V = 10m/s ➡ H = 5m V = 30m/s ➡ H = 45m 5m above Sea Level ? Unit 4 Rx. Bldg. 56m above Sea Level Unit 4 Tb. Bldg. 36m above Sea Level Tsunami velocity (10m/s) estimated based on water depth does not agree with a basic physics rule?? 26 After Tsunami Intake Screen Units Washed Away. Unprotected Discharge Outlet Directly Hit By Tsunami. 27 Implication to Other NPPs 28 Water-Drip-Marks: Evidence of Significant Steam Condensation On the Ceiling, Followed by Hydrogen Explosion Which Dispersed Insulation Powder on 4th Floor of Reactor Bldg. 29 Crashed Ventilation Duct Near The Ceiling of 4th Floor of Rx. Bldg.: An Evidence of Significant Upward Load Suggesting A Large Explosion Underneath. 30 Exploded Ventilation Duct to Main Stack: An Evidence of Another Explosion. 31 Natural-Nuclear Combined Disaster • More Than Just A Nuclear Disaster Rescue And Evacuation Plan Challenged Sheltering Strategy Not Effective • More Than Just An Natural Disaster Rescue Efforts For Potential Survivors Terminated In Early Stage Restoration Activities Not Efficient Less Places To Accept More Evacuees Intact Structure, But Not Usable Prolonged/Permanent/Irreversible Impacts Large Amount Of Contaminated Debris 32 Mar. 29, 2012 33 Last Defenses • How Useful Is Emergency Preparedness? How Accurate Is Evacuation Time Estimate? What Does Emergency Planning Zone (EPZ) Mean? • How Helpful Is Nuclear Liability? Total Cost Estimate ~ US$ 200B (by US-NAS) Image/Reputation Losses Alone of Fukushima-Scale Accident in France ~ € 166B (US$ 215B) (by IRSN) National Budget > US$ 200B: Only 20 Countries In The World. National Budget < US$ 200B: 14 Out Of 30 Nuclear Operating Countries. 34 Beyond EPZ • 16 km: • 80 km: Plume Exposure Pathway EPZ Ingestion Exposure Pathway EPZ Realities Beyond EPZ • EPZ Is Not An Impact Boundary • Many Local “Hot Spots” Outside EPZ • Highly Radioactive Sewage Sludge and Incinerator Ash 35 Ditches Are Typical Local “Hot Spots” Off-Scale > 5mR/h (50μSv/h) Oct. 9, 2011 3636 Sewage Treatment System Of Yokohama City Sewage Discharged = 602,860,000 m3/year Original Sewage Containing Undetectable Level (< 1Bq/kg) Volume Reduction 1/100 Originally Undetectable Level Is Now Detectable Through A Series Of Volume Reduction Processes Volume Reduction 1/40,000 Water Containing Decant Residue 5,480,000 m3/year Sludge Radioactivity Sludge Sedimentation Volume Reduction Concentrated Organic Matter Decomposed Dewatered Incinerated 37 Yokohama (300km from Daiichi NPP) • 13,000Bq/kg detected on 5/19/2011 • 3 containers of incinerator ash per day Incinerator Ash Unit Amount Annually Generated Baked Sewage Sludge Incineration Ash Primary Ash Fly Ash Noncombustible Waste Industry Waste Total Ton Radioactivity (First Year) Cumulative (7 years) • Nearly 1 TBq in 170,000 tons of radioactive waste generated in 7 years in Yokohama, 300 km away from Fukushima Daiichi NPP. Unit Amount Annually Generated Radioactivity (First Year) Cumulative (7 years) Ton Baked Sewage Sludge Incineration Ash Primary Ash Fly Ash Noncombustible Waste Industry Waste Total Psychological Perspectives • What Do “Limits”, “Thresholds”, and “Criteria” Mean to The Public? • How Helpful Are Science and Education? • Unreasonable Rumor or Logical Psychology? • What Does Forced Evacuation Mean? 40 Clearance Level • • • • 1999 2004 2005 2011 1,000 Bq/kg 800 Bq/kg 100 Bq/kg, IAEA level adopted 8,000 Bq/kg • US-EPA (green-field release): 4mrem/yr = 7.4Bq/kg • As of 3/30/2015, greater than 15Bq/kg is regularly detected and even greater than 50Bq/kg is not unusual at any waste incinerator in Tokyo. 41 Criteria for Cs-137 Bq/kg 500 Temporary Limit for Vegetable Radioactive Waste 100 Clearance Level for Concrete Debris Generated at Decommissioning Plants Non-Radioactive Waste 42 Criteria for Cs-137 Bq/kg 200 Temporary Limit for Drinking Water Radioactive Effluent 90 Limit for Nuclear Plant Effluent General Industry Effluent 10 WHO Limit for Drinking Water 43 If fish with Cs levels 1Bq/kg, 10Bq/kg, and 100Bq/kg are not traded at the same price at the market, is this an unreasonable discrimination? 44 We would like to serve our customers with the best fish we can find every day. Choosing safe, fresh, and contaminationfree fish and farm produce for the family is a simple natural psychology. 45 Young Fukushima women leaving hometowns 46 47 Sociological Impact: More Than Radiological Effects • Irreversible Community Disruption Deteriorating Hygienic Condition Damaged Infrastructure Abandoned Resident Houses, Stores, Office Buildings Residual Radioactivity. Minor Level Of Radioactive Contamination Fallout/Re-Suspension Still Cycling No/Few Young Women And Children No School, No Hospital • Issues to Belong to New Communities Complex Status of Accident Victims Compensation: Nuclear vs. Non-nuclear Transient: Crowed traffic, hospitals. Inflation triggered by “rich nuclear victims” distressing original residents and other victims. 48 Sociological Issues To Develop Good Relationship with New Communities • Victim Status: Tsunami, Earthquake, Nuclear • Residential Background: • Occupation: • Family Member: Infant/Children, Middle-Aged, Old, Handicapped, and any combination • Gender: Male, Female • Loss: Properties, Business, Family Member(s) • Evacuation Status: Temporary, Voluntary, Permanent • Compensation/Benefit Status: Medical Treatment • Frictions with Original Residents and Among Different Victim Statuses Pre-nuclear, “New Comer” Nuclear-related, Non-nuclear Tax Relief, Free Education, 49 You have been well paid before accident, and are paid a lot of compensation again after accident. Lucky guys! Hospitals, stores restaurants, roads are all crowded with you guys. Get out here now and go back to your own place. I lost whole family and house after Tsunami and am paid very little to restart my life. You have a nice family to live with. Tsunami Victims No more sympathy. We all know you are complaining more to be paid more. Original Residents You enjoy all benefits of our place without paying. We can no longer afford to buy houses because price went up so quickly after you guys moved in here! What can I say? Nuclear Victims 50 Mar. 29, 2012 51 Jul. 1, 201252 Dec. 24, 2012 53 It is eventually a matter of money, isn’t it? Minister, Of course not. If so, why so many evacuees chose to commit suicide? 54 “Nuclear-related Death” Over 1,000 Evacuees Died From Mental Degradation and Depression After Extended Evacuation Life 55 4 Years Later… Is Fukushima Situation Getting Better And More Predictable? • Unreliable Decommissioning Roadmap • Volume Of Contaminated Water Still Growing • Contaminated Groundwater Still Not Isolated • Little Regulator Involvement 56 57
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