Radiological Emergency Preparedness A Study of Federal, State, and Local Preparedness at Nuclear Power Plants

Transcription

1 Radiological Emergency Preparedness A Study of Federal, State, and Local Preparedness at Nuclear Power Plants Bill Webb, Technological Hazards Branch Chief Radiological Emergency Preparedness Program FEMA Region 10

2 CONTENT Nuclear Power Concepts Understanding Radiation & Release Radiological Emergency Preparedness (REP) History and Background Federal, State and Local REP Overview of Fukashima Disaster

3 Reactors

4 Boiling Water Reactor (BWR)

5 Fission Product Barriers 1st Barrier Fuel Cladding Sealed Zircaloy Tubes

6 Fission Product Barriers Large PWRs use 17x17 array of fuel pins Approx. 190 assemblies per reactor

7 Fission Product Barriers 2nd Barrier Reactor Coolant Loop

8 Fission Product Barriers 3rd Barrier Reactor Containment Building

9 Understanding Radiation

10 Ionizing Radiation Electromagnetic waves of extremely short wavelength (X-rays and gamma rays) and accelerated atomic particles (such as electrons, protons, neutrons, and alpha particles), deposit enough localized energy in an absorbing medium (like human cells) to dislodge electrons from atoms with which they interact and to disrupt chemical bonds. The loss of electrons creates particles known as "ions," and these types of radiation are termed "ionizing radiation

11 Natural sources of such radiation, which are all around us and to which all people are exposed, include cosmic rays, natural radioactive elements in the earth's crust, internally deposited radionuclides, and inhaled radon. Man-made sources include the use of X-rays in medical and dental diagnosis; radioactive materials in building materials, phosphate fertilizers, and crushed rock; radiation-emitting components of TV sets, smoke detectors, and other consumer products; radioactive fallout from atomic weapons; and nuclear power.

12 Ionizing versus non-ionizing radiation

13 As ionizing radiation penetrates a living cell, it collides randomly with atoms and molecules in its path, giving rise to ions, free radicals, and other molecular alterations that may injure the cell. DNA is the most critical biological target because of the limited redundancy of the genetic information it contains. Most damage is reparable. Though any damage to DNA that remains unrepaired or is improperly repaired may result in a mutation or chromosome aberration.

14 Ionizing Non-Ionizing

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16 Radiation Dosage In the United States, absorbed dose is commonly given in rad or Gray and other protection quantities, such as equivalent dose and effective dose, are given in rem. The following table is provided to help avoid confusion among persons not familiar with these quantities. The use of the newer system of units would be particularly useful during radiological incidents involving international responders.

17 Conversions for Effective Dose, Equivalent Dose, Dose Equivalent, and ambient dose equivalent 0.001rem=1mrem =0.01mSv 0.01rem=10mrem=0.1mSv 0.1rem=100mrem=1mSv=0.001Sv 1rem=1000mrem=10mSv= 0.01Sv 10rem=100mSv =0.1Sv 100rem=1000mSv=1Sv(Sievert) 1000 rem=10 Sv The radiation absorbed dose is measured in Gray, rad, rem and Sievert (Sv). Measured Dose (Temporary Measurements) by gamma radiation or X-rays 1 R (roentgen) = 0.01 Gy = 0.01 Sv

18 Studying Radiation Measurement

19 Protected by: Time Distance Shielding

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21 Components of an Accidental Release RPPC

22 Release Pathways Loss of Coolant Accident Core Damage Cladding failure Fuel damage (melt) Containment Failure Indirect Path Filtered Unfiltered Direct Path

23 Radiation Exposure Pathways Submersion in Plume Inhalation of radionuclides Exposure to ground contamination Inhalation of re-suspended radionuclides Ingestion of contaminated food or water Milk Pathway Air-Grass-Cow (or Goat) -Milk-Child

24 Time Factors Associated with Release = Time from the initiating event to start of atmospheric release 0.5 hours to several hours Time period over which radioactive material may be released = 0.5 hours to several days

25 Atmospheric Diffusion Inversions (temperature) Building wake Deposition Local terrain Precipitation

26 The Radiological Emergency Preparedness Program RCCC

27 REP Program Mission Statement: The Radiological Emergency Preparedness Program (REPP) coordinates the National effort to provide State, Tribal and local governments with the relevant and executable planning, training and exercise guidance and policies necessary to ensure that adequate capabilities exist to prevent, protect against, mitigate the effects of, respond to and recover from incidents involving commercial nuclear power plants. The program assists State, Tribal and local governments in the development and conduct of offsite radiological emergency preparedness activities within the emergency planning zones of NRC licensed commercial nuclear power facilities. RCCC 3-4

28 History of REP - TMI View Video (TMI) ubk0&p=937b0e873f58a3d7&annotation_id=annotation_358537

29 RCCC 3-6

30 History of REP - TMI March 28,1979 Accident occurred at the Three Mile Island Nuclear Power Plant in Pennsylvania. TRIGGERED OFFSITE INVOLVEMENT RCCC 3-7

31 Accident at Unit 2 History of REP - TMI Generated fear of widespread radioactive contamination RCCC 3-8

32 History of REP - TMI RCCC 3-10

33 History of REP - TMI RCCC 3-11

34 RCCC 3-12

35 History of REP - TMI Led NRC to place emphasis on operator training, "human factors" in plant performance, severe accidents that could occur as a result of small equipment failures, emergency planning, plant operating histories, etc. Lack of knowledgeable person providing information to public RCCC 3-13

36 PRE-TMI STRUCTURE Voluntary Concurrence Program of NRC NRC lead role for both onsite and offsite preparedness NRC coordinated Federal Radiological Emergency Preparedness Activities Defense in depth (plant safety systems) POST-TMI STRUCTURE NRC Voluntary Concurrence Program evolved into FEMA's "350 Process;" offsite planning and preparedness a condition of licensing (P.L , 6/30/80) NRC lead onsite role; FEMA lead offsite role FEMA coordinates Federal Radiological Emergency Preparedness Activities Beyond defense in depth (plant safety systems and offsite preparedness) RCCC 3-14

37 The Kemeny Commission established two weeks after the TMI accident Report issued in October 1979, recommended that FEMA be responsible for reviewing and approving offsite radiological planning Large amount of radioactivity inside containment. Plant authorities did not know what was happening and took no protective actions. Many residents voluntarily evacuated in orderly manner. Although there were 40,000,000 Ci of I-131 released from the core into containment, only 15 Ci were released over several days into the environment. RCCC 3-15

38 Executive Order March 31, 1979 Established FEMA Presidential Directive December 7, 1979 The Beginning... FEMA to take lead in offsite emergency response planning for commercial nuclear power plants REP Program created RCCC 3-17

39 History of REP - Chernobyl Sentinel world event rekindling fear about nuclear power CHERNOBYL RCCC 3-18

40 April 26,1986 Accident occurred at the Chernobyl Nuclear Power Plant in the Ukraine THERE WAS A RADIOACTIVE RELEASE RCCC 3-19

41 Melted Core Being Carried RCCC 3-20

42 History of REP - Chernobyl Cause of Incident: Accident at Unit 4 Release due to flawed reactor design Plant was operated with inadequately trained personnel and without proper regard for safety RCCC 3-21

43 History of REP - Chernobyl Different type of reactor than U.S. Used graphite instead of water. Plant was conducting a test to determine how long the plant could maintain self-sufficient power after a reactor shutdown. Several automatic trip and power control systems were either disconnected or not reset. This led to inability to operate control rods. RCCC 3-22

44 History of REP - Chernobyl Lessons learned: Reactor failure resulted in upward explosion, resulted in large area of dispersion. Mix of release changed over time. Plume affected by wind. Higher radiation pockets farther away due to rain-out.

45 So What s In REP?

46 Emergency Planning Zones (EPZs) Requirements for State and Local Agencies Vary by Distance from the Plant (i.e., Emergency Planning Zone) Plume Exposure Pathway EPZ 10-Mile Radius Individuals could suffer direct radiation impact from off-site exposure States must participate jointly with licensee and appropriate local governments in an exercise at least every 2 years. Ingestion Pathway EPZ 50-Mile Radius Individuals could suffer indirect radiation impact from off-site exposure via food chain States must participate jointly with the licensee and appropriate local government in an exercise at least every 6 years. 10-mile EPZ 50-mile EPZ RCCC 3-24

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48 RCCC 3-25

49 OFFSITE/ONSITE Offsite (State and Local Governments) Onsite (Utility-Owned Property)

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51 Risk Significant Planning Standards Planning Standard D - Emergency Classification Systems Planning Standard E - Notification Methods and Procedures Planning Standard I - Accident Assessment Planning Standard J - Protective Response RCCC 6-6

52 Planning Standard D Emergency Classification System RCCC 6-14

53 Emergency Classification Levels (ECLs) Notification of Unusual Event Alert Site Area Emergency General Emergency RCCC 6-15

54 Notification of Unusual Event Potential degradation of the level of safety of the plant OR indication of a security threat to facility protection has been initiated. No releases of radioactive material requiring offsite response or monitoring are expected unless further degradation of safety systems occurs. Poses no threat to public safety, but warrants increased awareness RCCC 6-16

55 Alert Actual or potential substantial degradation of the level of safety of the plant OR a security event that involves probable life threatening risk to site personnel or damage to site equipment because of intentional malicious dedicated efforts of a hostile act. Any releases expected to be limited to small fractions of the EPA Protective Action Guides (PAGs) (no threat to public). RCCC 6-17

56 Site Area Emergency Actual or likely major failures of plant systems needed for protection of the public OR security events that result in intentional damage or malicious acts: Toward site personnel or equipment that could lead to the likely failure of, or Prevents effective access to equipment needed for the protection of the public. Any releases not expected to exceed EPA PAGs beyond site boundary. May require precautionary protective actions. RCCC 6-18

57 General Emergency Actual or imminent substantial core degradation or melting with potential for loss of containment integrity OR hostile actions that result in an actual loss of physical control of the facility. Release can be reasonably expected to exceed EPA PAGs offsite for more than the immediate site area. Protective actions necessary. RCCC 6-19

58 Notification Methods and Procedures Notification of OROs Procedures to notify OROs based on ECLs and verify message. Notification & mobilization of emergency response personnel. During HAB, notification may not originate with the plant assure notification channels work in all directions. RCCC 6-22

59 Information from licensee (usually recorded on a form) Location of incident, date & time Class of emergency Type of release (chemical/physical form, projected dose rate) Affected population Protective measures recommended Meteorological Conditions RCCC 6-23

60 Planning Standard E (continued) Notification of public Offsite organization plans/procedures should describe the system(s) used to disseminate information to the public. This standard addresses the means to alert and notify the public within the Emergency Planning Zone (EPZ) of an event at the plant. It covers both administrative procedures and physical means for notifying the public. (Message and sirens) RCCC 6-24

61 Planning Standard E (continued) Administrative means: Specify organizations or individuals, by title, responsible for activating the alert and notification system, including alternates. Describe procedures that demonstrate that once the appropriate official has decided to activate the system, it will be activated in a timely manner. Procedures should ensure that a legitimate and clearly understood command to activate the system will be conveyed from the appropriate officials to the persons responsible for physically activating the system. RCCC 6-25

62 Planning Standard E (continued) Physical: System will assure direct coverage of essentially 100% of the population within 5 miles of the site. Arrangements will be made to assure 100% coverage within 45 minutes of the population who may not have received the initial notification within the entire 10 mile EPZ. An effective alert and notification system may include more than one physical alerting method. Each physical means should be addressed in the plan. Consider a backup plan! Alert and notification method for institutions (such as recreational areas, schools, factories, hospitals, shopping centers, jails, and large office buildings) may require different systems (i.e., tone alert) RCCC 6-26

63 Planning Standard E (continued) Emergency Alert System (EAS) Message requirements Name & office of person authorized to release message Name of plant and that an emergency condition exists Refer to Public Information Guide Stay tuned for further instructions *Sometimes pre-scripted RCCC 6-27

64 Accident Assessment Each organization shall describe the capability and resources for field monitoring within the plume EPZ. Each organization, where appropriate, shall provide methods, equipment, and expertise to make rapid assessments of the actual or potential magnitude and locations of any radiological hazards. This shall include activation, notification means, field team composition, transportation, communication, monitoring equipment, and estimated deployment times. Perform laboratory analyses of radioactivity in air, liquid, and environmental samples. RCCC 6-36

65 Accident Assessment Fixed Monitoring sites Sampling Aerial measurements Soil, air, vegetation Field monitoring teams Briefings (Information prior to deployment) Locations of field teams (Movement of teams and sample locations) Equipment use checks, calibration, inventory RCCC 6-37

66 Planning Standard J Protective Response Who are we protecting? Permanent Residents US Census data, estimate vehicles on road (ETEs) Transient population Special populations School Children Day Care Hospitals At Need Populations RCCC 6-39

67 How to protect them - Protective Actions Based on EPA Manual of Protective Action Guides (PAG) and Protective Actions for Nuclear Incidents - published in 1992 A PAG is the level of projected dose to individuals in the population that warrants taking protective action. Projected dose means the dose that would be expected if no protective actions were taken. Protective/precautionary Action Recommendations Protective/precautionary Action Decisions RCCC 6-40

68 Protective Action Guides Dose limit (rem) Activity <01 Public should be evacuated <05 Emergency workers & special populations (institutionalized, mobility impaired) <10 Emergency workers protecting valuable property <25 Emergency workers performing life saving measures >25 Voluntary only (EW- life saving) RCCC 6-41

69 Protective Actions (Continued) The objectives of protective actions: Remove or keep people from the possible exposure area (traffic control, etc) Shield people from release (shelter in place) Limit damage caused by radiation exposure (potassium iodine (KI), decontamination) Limit radioactive material ingested through foods (animal sheltering, food monitoring) RCCC 6-42

70 Examples of Protective Actions Evacuation Sheltering in place (institutionalized populations) Access Control Use of potassium iodine (KI) thyroid blocking drug Use of stored feed and protected water for animals Condemnation of food supplies Relocation Decontamination RCCC 6-43

71 Planning for Evacuation List of relocation centers with capacity Describe the management and security of centers Transportation of mobility impaired Equipment and staffing Centrally located pickup points for general population without vehicles? Describe evacuation routes with narrative and maps If institutionalized populations will not be evacuated, what are alternate Protective Action Decisions (PADs)? Traffic and access control Staffing/equipment Provide ID for emergency workers and their vehicles RCCC 6-44

72 Planning Standard J (continued) Things to consider in planning: Identify impediments, such as inclement weather, high traffic density, and/or threat conditions (HAB). Identify traffic and access control points. Conduct an evacuation time estimate for the evacuating area (seek guidance from a Subject Matter Expert). Appendix 4 KI to emergency workers and/or public. Food Control Measures and Crop Embargo Issues RCCC 6-45

73 Unit REP Planning Guidance On-site Initiating Condition Protective Actions Off-site Initiating Condition EPA PAGs EPA PAGs Alert NPP EAL ECL PAR Notifications PAD NPP Nuclear Power Plant EAL Emergency Action Level ECL Emergency Classification Level NOUE Notification of Unusual Alert SAE Site Area Emergency GE General Emergency EPA Environmental Protection Agency PAG Protective Action Guidelines PAR Protective Action Recommendation PAD Protective Action Decision Emergency NOUE Alert SAE GE Onsite* Offsite Notifications RCCC 6-46

74 Fukushima Dai-ichi Disaster

75 Fukushima Dai-ichi plant Six BWR units at the Fukushima Nuclear Station: Unit 1: 439 MWe BWR, 1971 (unit was in operation prior to event) Unit 2: 760 MWe BWR, 1974 (unit was in operation prior to event) Unit 3: 760 MWe BWR, 1976 (unit was in operation prior to event) Lake Barrett Unit 4: 760 MWe BWR, 1978 (unit was in outage prior to event `hot fuel recently moved to fuel storage bay) Unit 5: 760 MWe BWR, 1978 (unit was in outage prior to event) Unit 6: 1067 MWe BWR, 1979 (unit was in outage prior to event)

76 Earthquake 2011 March - magnitude 9.0 earthquake occurs off shore from Sendai Region Lake Barrett Plant loses sources of off-site power, All Units automatically shutdown safely within seconds Plant designed for 8.2 earthquake. 9.0 is 8 times larger in magnitude

77 Tsunami Tsunami hits with over 30 foot wave and ocean surge. Wave was larger than the design basis protective wall. Lake Barrett Site is overwhelmed and flooding takes out all of the multiple sets of emergency diesel generators. Batteries remain the only available power.

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80 Mark 1

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83 Hydrogen Explosions The fuel rods heated up and the Zircaloy cladding underwent an energetic water reaction converting to Zirchromium Oxide and Hydrogen. The hydrogen gas would normally be made inert or ignited or vented to atmosphere through an external stack but nothing was working due to loss of power. The operators had to vent the hydrogen to the secondary containment building where it exploded.

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91 Comparison to TMI and Chernobyl TMI was almost a full core meltdown (2/3 of the core) due to loss of cooling water like Fukushima. - Most radioactivity was kept in the containment bldg. - Actual release to the public was minor (about the equivalent of two chest x-rays. Chernobyl was an explosive event causes by the breakup of the core due to an increase in core pressure that blew the containment lid off the reactor. - Radioactive release was caused by the fire in the Carbon Moderator which caused a thermal uplift into the atmosphere. - Chernobyl had no containment. - Ground contamination by plume and serious human exposure.

92 Changes to US Mark 1 Reactors already in effect NRC issued a generic industry requirement in 1980 The modifications made to Mark I containments include: Quenchers were installed to distribute the steam bubbles in order to produce rapid condensation and to reduce loads on the unit. In a reactor, exhaust steam is piped into a suppression chamber, which is known as the torus and is a large, rounded suppression pool that sits next to the reactor core. It is used to remove heat when large quantities of steam are released from the reactor. In the torus, the steam bubbles go under water. With the modification to the Mark I, the quenchers, which are also underwater, make steam bubbles smaller by breaking up the larger bubbles. This in turn reduces pressure. Another modification is the installation of deflectors inside the torus. When that steam goes in, the water level rises. The deflectors that were added break up the pressure wave that is produced and help relieve pressure on the torus. A further modification was made to the saddles on which the torus sits basically the series of leg-like structures that support it. The construction was fortified, as was the steel, to accommodate the loads that are generated.

93 What Went Wrong? "The Japanese decision-making process, of group decision-making and not individual decision-making, might have been a hindrance for dealing with a situation like this," he says. "It's hard to know, but the timeframe demands of making decisions like this, that are multibillion-dollar decisions, would be difficult in the Japanese culture to do as promptly as maybe it would be done here. - Lake Barrett, Retired Nuclear Engineer One critical decision was whether to pump seawater into the reactors. That would certainly ruin them, but it could also keep them cool and prevent meltdowns. It appears that the engineers on site hesitated for some hours before they went ahead and did that. Per Peterson, chairman of nuclear engineering at University of California, Berkeley says that was a questionable decision. "It's quite likely that if the injection of seawater had been initiated earlier, the damage of fuel could have been limited greatly or even prevented," Peterson says. "So I think there are possible pathways by which the severity of the accident could have been substantially less."

94 Preparing For The Worst That's one area where Japan may have fallen short. Marvin Fertel, president of a trade group called the Nuclear Energy Institute, told a recent panel at the National Academy of Sciences that U.S. reactor operators get better training than their counterparts in Japan. "What we like for the operators and the security guards when we're operating the plants is just boredom," he said. "Everything is just good. So the time we really want them to train and plan for bad events is when they're in a simulator." These simulators mimic each specific nuclear power plant closely. That allows reactor operators to practice dealing with extreme emergencies as they would experience them in their own control rooms. "In Japan," Fertel said, "we understand they: (1) do not have plant-specific simulators: they have generic simulators for the types of plant they have; and (2) they don't have one for every plant. That means less-realistic training and less time to practice, Fertel said. Whether better training would have made a difference at Fukushima is something that should emerge from the ongoing investigation in Japan.

95 Comparison of Japanese and U.S. Plants and Policies Japanese United States Diesel Generators were emplaced I the basements of the plant buildings Fuel Supplies were not protected in external sites Building did not have waterproof door and entrance seals Plant modifications were not always inspected by the Nuclear Regulatory Agency Lack of Inspectors on Site Oldest of Japan s Reactors: 1 st Generation Mark 1 Reactor Off-Site Emergency Plans outdated, not reviewed periodically, certified and not fully exercised Plant Operators do not have adequate practice in emergency response and operation Lake Barrett Auxiliary generated are mandated to be in above ground and protected storage Fuel Supplies are in hardened and protected shelters All building are equipped with seals The NRC mandates and ensures that all work is inspected and documented for compliance according to the plant license NRC inspectors are on-site at all Nuclear Plants US Mark 1 plants have undergone NRC directed improvements and modifications. FEMA REP works continuously with the off-sites, review plans, conducts exercises and evaluation and annually certifies for Reasonable Assurance The NRC mandates yearly training and certification of operators and all operators are ran through simulator training and testing annually. Significant differences in Culture, Management, Oversight, Construction, Regulations and Planning

96 Lake Barrett