Compare and contrast major nuclear power plant disasters: Lessons learned from the past

Transcription

1 Compare and contrast major nuclear power plant disasters: Lessons learned from the past Presenter: Sayanti Mukhopadhyay Authors: Sayanti Mukhopadhyay, Jessica Halligan and Makarand Hastak Date: th International Conference of the International Institute for Infrastructure Resilience and Reconstruction (I3R2); Purdue University, West Lafayette IN 47906; May 2014

2 Background Problem Statement Research questions Research Framework Case Studies Results & Discussion Conclusion References Outline

3 Nuclear Power Plants (NPP) Most complex & sophisticated energy systems designed to produce low carbon electrical energy (low GHG emission) Green House Gas (GHG) emissions caused an additional 150,000 deaths (2000) since 1990 attributable to A. Global warming: Climate change B. Air pollution: Malnutrition, Diarrhea & other health related problems (Markandya & Wilkinson, 2007 NPP s construction marks a major step towards reducing GHG emissions compared to the conventional coal-fired / oil-fired power plants

4 Nuclear Power Plants Rank Generation facilities (Technologies) Mean Low High Tonnes CO 2 e/giga-watt-hour 1 Lignite Coal Oil Natural gas Solar PV Biomass Nuclear Hydroelectric Wind

5 Safety of NPP: Opinions split! Total operation time of commercial nuclear power: over 15,000 cumulative reactor-years # countries operating NPP: 33 countries only a few major accidents (TMI, Fukushima & Chernobyl) occurred Safest & most secure industry due to: Stringent Federal regulations Automated & robust safety systems Industry s commitment towards safety & security

6 Safety of NPP: Opinions split! Jim Riccio, nuclear policy analyst for Greenpeace USA, said in 2011, "We've always believed that it's an inherently dangerous technology that should be phased out and replaced Fukushima Daiichi Nuclear Accident, Japan in 2011 is a wakeup call to the entire nuclear industry Questions being raised about social benefits & costs of nuclear power

7 Research Questions Question 1 Why is there a difference in perspective about the safety of NPPs? Question 2 What were the root causes behind the major nuclear accidents? Question 3 Are there some commonalities in the root causes? Question 4 If so, what lessons can we learn from the failures in the past?

8 Research Framework Case Study Selection Most severe NPP accidents as ranked by INES Identification of causes Literature review: Journals, Reports, News Articles, etc. Comparative Analysis of causes Categorize causes Compare causes Lessons Learned Literature review Analysis of the causes & consequences

9 CASE STUDIES

10 INES Ranking Scale International Nuclear and radiological Event Scale (INES, 2013)

11 Chernobyl Disaster: INES Rank 7 Risky Experiment - testing if residual energy from torque of a turbine can run a turbinegenerator in event of a station black-out Goal: Keep the cooling pumps running in the brief (100 seconds) gap between the blackout & running of the back up generators Chernobyl, USSR April 25, Faulty design of RBMK Reactor 2. Safety violation 3. Less experienced & poorly trained operators 4. Operator s error x10 6 curies of radioactivity release 2. Huge heat transients release onsite operators killed 4. Death of liquidators 5. Thyroid cancer in children 6. General health of the inhabitants (30 km in radius)

12 Fukushima Daiichi : INES Rank 7 1. Great East Japan Earthquake (9.0 Richter scale), off the Sanriku coast of Japan 2. Generated series of Tsunamis along coast of Japan 3. Tsunamis waves average height 15 m >> Design basis tsunami height 5.7 m 4. Consecutive nuclear meltdowns & reactors explosion Fukushima Daiichi, Japan March 11, Emergency cooling system generators located in basement 2. Safety records falsification 3. TEPCO ignored flood warning 4. Geographic location (Pacific Rim) 1. Erratic spread of radioactive plumes 2. Contaminated soil & sea-water 3. Harmed cattle & livestock industry 4. Neighborhoods uninhabitable 5. Government mistrust & instability in nuclear industry

13 Three-Mile Island : INES Rank 5 1. Worst nuclear accident in the United States commercial nuclear industry 2. Completely destroyed the reactor due to LOCA (Loss of Coolant Accident) Three-Mile- Island, USA March Mechanical failure of the valve in the secondary loop 2. Equipment failure (PORV valve) 3. Faulty design of PORV valve indicator 4. Violation of NRC safety regulations 5. Inaccurate water level measuring instrument inside reactor core 1. Post traumatic stress in public 2. Psychological impact on pregnant women and mothers 3. Mismanagement in hospitals 4. Adverse impact on nuclear industry

14 Chalk River Accident : INES Rank 5 Chalk River, Canada December 12, Occurred due to human flaws, operating errors and miscommunication among the supervisor & the operating personnel 2. Completely destroyed the reactor 1. Mistake in operation of the NRX Reactor 2. Supervisor s mistake of ordering the wrong button to push 3. Miscommunication 4. Mistaken removal of the safeguard bank of control rods 1. Series of steam and hydrogen gas explosions spewed thousands of radioactivity 2. Completely destroyed the nuclear core 3. Not much contamination spread far & wide and none of the workers were injured

15 SL-1 Accident : INES Rank 4 SL-1, USA January 3, During routine maintenance, the central control rod was removed too far causing reactor to suffer a prompt criticality accident 2. Steam explosion released radioactivity, but was contained within the building 1. All the 3 operators on-site died 2. Huge power surge led to fuel cladding swelling 3. The reactor vessel (5 Metric ton weight) disengaged & jumped to a height of 3m 1. Improper removal of the central control rod 2. Uplifting of the rods by 50 cm instead of 10 cm 3. Stickiness of central rod

16 Major Causes Faulty Design Operator s error Equipment Failure Lack of trained professionals CAUSES Violation of safety regulations Inadequate safety & warning system

17 Comparative Analysis: Major causes Issues Chernobyl FDNPP Chalk-river TMI SL-1 Faulty Design x x x Equipment Failure x Inadequate Safety & Warning Systems x Violation of Safety Regulations x x x x x Lack of Trained Professionals x x Operators error x x x x x

18 Pockets of improvement Lessons learned Safety Training Response & Mitigation Strategies Communication & coordination Response & Recovery Public health recovery Evacuation planning

19 Safety & Training 1. Fukushima disaster More sophisticated & accurate weather forecasting systems are needed helps to get prepared for the upcoming disaster 2. TMI accident NPPs must strictly follow the safety regulations guidelines as proposed by the nuclear regulatory commissions (operating & shutdown phases) 1. Adequate technological training for all the operating personnel working in a NPP is absolutely necessary. 2. Health physicians of the NPP s surrounding hospitals should be specially trained to handle the emergency situations efficiently.

20 Response & Mitigation Strategies Govt. must communicate the severity & health impacts disaster Efficient areawide telecommunication system Efficient communication between nuclear engineers & health physicians Contingency plans prepared by the hospitals Transportation facilities readily available to the hospitals & other health care facilities Sale of milk & food products strictly prohibited Adequate funding for recovery Provide health counseling in affected areas Special attention to pregnant women & small children Systematic distribution of prophylactics thyroid blocking agent Immediate evacuation orders by the govt.

21 Conclusion Reviewed 5 major NPP accidents Analyzed, compared & contrasted the causes of those accidents to find the common issues We found violation of safety regulations & operator s error were the most frequently occurring issues in the past accidents Adequate safety measures & training of the operators are essential Necessary response & mitigation strategies must be planned well in advance while operating a NPP.

22 References 1. Markandya, A., & Wilkinson, P. (2007, September 13). Electricity generation and health. Lancet, 370, 12. doi: /s Aoki, M., & Rothwell, G. (2013). A comparative institutional analysis of the Fukushima nuclear disaster: Lessons and policy implications. Energy Policy, 53, Retrieved 02 18, 2014, from 3. Safety of Nuclear Power Reactors (2014). World Nuclear Association (WNA),Retrieved May 9, 2014, from Plants/Safety-of-Nuclear-Power-Reactors/ 4. Shogren, A. (2011). Are nuclear power plants safe? Environmentalists are split, National Public Radio News and Archive, Japan Series, Published March 28, Retrieved May 9, 2014 from 5. Safety and Security, Nuclear Energy Institute, Issues & Policies. Retrieved May 9, 2014 from

23 Acknowledgement

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