This introduction is based on a White Paper distributed to the participants of the May 13, 2014, symposium titled The Science and Response to a Nuclear Reactor Accident. It is intended to provide factual background information on federal and state responsibilities related to responding to a nuclear reactor accident and nomenclature related to protective action guidance at the different phases of a nuclear reactor accident. Some information in this chapter was distilled from introductory remarks made at the symposium by organizing committee member Dr. Steven Simon, National Cancer Institute (NCI).
There are 100 nuclear reactors in the United States operating at 62 sites in 31 states. These plants are regulated by the Nuclear Regulatory Commission (NRC). After the 1979 Three Mile Island accident, the NRC required that each site have onsite and offsite emergency response plans to protect the plant workers and members of the public from radiation exposure in the event of a nuclear reactor accident.1 In the case of a nuclear reactor accident that results in release of radioactive materials to the atmosphere, possible means of exposure to radiation are direct external exposure from the plume and deposited material and internal exposure resulting from the inhalation or ingestion of radioactive material. Offsite response, the focus of this symposium, includes evacuation, sheltering in place, use of potassium iodide (KI), food interdictions, or other protective actions.2
The NRC has defined two emergency planning zones (EPZs) around nuclear power plants. According to the NRC, EPZs are designated as “the areas for which planning is recommended to assure that prompt and effective actions can be taken to protect the public in the event of an accident.”3 The actual size and shape of the EPZs vary from plant to plant and depend on the site layout, geographical features of the surrounding area, political subdivisions, and characteristics of the surrounding community such as land use. However, typically:
1 Dr. Steven Simon, NCI, provided the following definition for a nuclear accident: “It is an unpredictable, unusual, and unwanted event involving radiation and/or radioactive materials which result in occupational or public exposure and contamination of structures, property, or persons.” A nuclear reactor accident is a type of a nuclear accident.
2 For example, an action that may be undertaken to protect agricultural interests is to place dairy animals on stored feed.
3 Nuclear Regulatory Commission and Environmental Protection Agency, 1978, Planning Basis for the Development of State and Local Government Radiological Emergency Response Plans in Support of Light Water Nuclear Power Plants, NUREG-0396/EPA 520/1-78-016, http://pbadupws.nrc.gov/docs/ML0513/ML051390356.pdf.
- The EPZ region designated for protection from the plume exposure has a radius of about 10 miles (~16 km). Protective action plans in this region that may call for evacuation, sheltering in place, and use of KI are in place to protect populations from potential exposures to radiation.
- The EPZ region designated for protection from ingestion of radioactive materials has a radius of about 50 miles (~80 km). Protective action plans in this region that may call for restrictions in the consumption of contaminated food and water or on land use are in place to prevent or reduce exposure from potential ingestion of radioactive materials.
Plant personnel are at all times responsible for onsite accident response and for limiting the consequences of the accident by preventing radioactive releases offsite.
The offsite response to a nuclear reactor accident starts with the plant personnel, among other response actions, notifying state and local authorities and the NRC about the occurrence of the accident. If the accident is likely to result in a radiation dose that reaches federal government protective action guides (PAGs), plant personnel make protective action recommendations to the state and local authorities.4 The Environmental Protection Agency (EPA) defines a PAG as the projected radiation dose from an unplanned radioactive release at which a protective action to minimize or avoid that dose and therefore risk from that dose is recommended.5
States and counties where nuclear reactors are located are responsible for the preparation of radiological emergency response plans.6 The purpose of these plans is to organize and coordinate actions taken by the plant owner, federal and state agencies, local governments, and support groups and to allocate and deploy resources and personnel in response to an emergency.
State and local authorities are responsible for making decisions and issuing orders for protective actions. These decisions are based on the status of the plant, prognosis for the accident, and meteorological conditions. Other responsibilities of state and local authorities include independent plume modeling and dose projection, offsite tracking of radioactive releases, sampling of the environment and the food supply for contamination, establishing and operating reception centers that provide radiation monitoring and decontamination for members of the general public, and providing recommendations to the agricultural community.
Several federal agencies provide guidance to state and local governments during a nuclear reactor accident. These agencies and state and local authorities coordinate the responses to the accident through an individual or joint Incident Command System. Dissemination of accident-related information to the news media and members of the public is coordinated by a Joint Information Center.
The President of the United States is kept informed about all aspects of the emergency and has the authority to accelerate federal emergency response in the absence of a specific request from state officials.7
Some of the roles and responsibilities of eight federal agencies during a nuclear reactor accident are discussed here. A comprehensive listing is provided in federal planning documents such as the National Response Framework (NRF)8 and radiation-specific documents such as the NRF’s Nuclear/Radiological Incident Annex. These docu-
4 Federal Emergency Management Agency, 2008, Nuclear/Radiological Incident Annex, http://www.fema.gov/pdf/emergency/nrf/nrf_nuclearradiologicalincidentannex.pdf.
5 Environmental Protection Agency, 2013, PAG Manual: Protective Action Guides and Planning Guidance for Radiological Incidents, http://www.epa.gov/rpdweb00/docs/er/pag-manual-interim-public-comment-4-2-2013.pdf.
6 In many jurisdictions, municipalities (cities and towns) also have that responsibility.
7 Robert T. Stafford Disaster Relief and Emergency Assistance Act, Public Law 93-288, as amended, 42 U.S.C. § 5121 et seq.
8 Department of Homeland Security, 2014, National Response Framework, http://www.fema.gov/media-library-data/20130726-1914-250451246/final_national_response_framework_20130501.pdf. The NRF contains 15 Emergency Support Function (ESF) Annexes that include protocols for communications (ESF #2), Public health and Medical Services (ESF # 6), Long-Term Community Recovery (ESF # 14), and External Affairs (ESF #15).
ments also define the process and structure for coordinated delivery of federal assistance should federal assistance be requested by the state and local governments.
Department of Homeland Security (DHS)
Pursuant to the Homeland Security Act of 2002,9 DHS has the overall responsibility for coordinating the federal response to a domestic nuclear reactor accident. If a state requests federal assistance, DHS reviews the situation and determines whether to assume federal leadership for the overall response in accordance with the NRF. DHS also leads the Interagency Modeling and Atmospheric Assessment Center (IMAAC), which provides interagency coordination of atmospheric dispersion modeling capabilities for producing and disseminating predictions of the effects from radiological releases.10
The Federal Emergency Management Agency (FEMA) is responsible for coordinating the provision of federal assistance to state and local government agencies during a nuclear reactor accident. FEMA is also responsible for overseeing offsite preparedness of state and local authorities through its Radiological Emergency Preparedness program.11
Nuclear Regulatory Commission (NRC)
The NRC is responsible for monitoring and providing assistance to plant personnel to mitigate the consequences of a nuclear reactor accident. This includes assessing the status of the plant, accident progression, and onsite activities. It may also provide technical assistance to state and local governments for source-term, plume-dispersion, and dose-assessment calculations to supplement those of the plant and offsite response organizations.
Environmental Protection Agency (EPA)
One of EPA’s roles prior to an emergency is to provide PAGs to assist emergency responders with their recommendations on protective actions.
During a response, EPA supports environmental radiological monitoring and assessment, as well as participates on the Advisory Team for Environment, Food, and Health.12 This team develops coordinated recommendations on environmental, food, and health matters and assists in the development and implementation of a long-term plan for monitoring radioactivity in the environment. It also assists in the development and implementation of a long-term recovery plan.
Department of Health and Human Services (HHS)
HHS is responsible for providing guidance to state and local authorities on health effects from exposure to radiation following a nuclear reactor accident and how to minimize physical and psychological adverse health effects from exposure to radiation. HHS also provides medical guidance to individuals exposed to radiation and
10 IMAAC participating agencies are the Nuclear Regulatory Commission, Department of Defense, Department of Energy, Environmental Protection Agency, Department of Health and Human Services, National Oceanic and Atmospheric Administration (Department of Commerce), and National Aeronautics and Space Administration. The Defense Threat Reduction Agency (DTRA) serves as the technical operations hub of the IMAAC. As such, DTRA coordinates the requests for atmospheric dispersion modeling, performs modeling, and distributes the modeling products to the requestors. See http://www.ofcm.gov/homeland/gmu2013/Presentations/IMAAC%20Fact%20Sheet%20-%20GMU.pdf; communication with Dr. Daniel Blumenthal, Department of Energy/National Nuclear Security Administration.
11 Nuclear Regulatory Commission and Federal Emergency Management Agency, 1980, Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness in Support of Nuclear Power Plants, NUREG-0654/FEMA-REP-1, http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr0654/.
12 The Department of Agriculture (USDA), the Food and Drug Administration (FDA), and the Centers for Disease Control and Prevention (CDC) are also part of the Advisory Team for Environment, Food, and Health.
may assist with laboratory bioassays to assess human exposures. Additionally, it provides guidance on conducting surveillance of exposed populations for potential long-term health effects.
Within HHS, the Office of the Assistant Secretary for Preparedness and Response13 is responsible for preparing for and responding to the public health and medical effects of natural and man-made disasters.
Food and Drug Administration (FDA)
As noted previously (see note 12), FDA participates in the Advisory Team for Environment, Food, and Health. It provides laboratory capabilities and Derived Intervention Levels (DILs)14 for possible embargo of contaminated foodstuffs.
Department of Energy (DOE)
DOE’s National Nuclear Security Administration (NNSA) coordinates federal environmental radiological monitoring and produces predictive plume models and dose assessments. This information is provided to decision makers at the federal, state, and local levels to assist with making protective action decisions and communicating them to the public.
NNSA has a variety of emergency response assets to map the probable or actual spread of radioactivity in the environment. They include the National Atmospheric Release Advisory Center (NARAC) for plume and deposition modeling,15 the Aerial Measuring System for measurements of actual ground deposition with aircraft-mounted detectors, and the Radiation Emergency Assistance Center/Training Site (REAC/TS)16 to provide specialized assistance, training, and dose assessment related to the medical management of radiation injuries. NNSA can establish a Federal Radiological Monitoring and Assessment Center (FRMAC)17 to help integrate consequence management resources and coordinate the development of a common operating framework.
Department of Agriculture (USDA)
The USDA may assist with the collection and assessment of agricultural samples within the ingestion exposure pathway EPZ to determine the effect of radioactive materials released during a nuclear reactor accident on agriculture. Also, in conjunction with HHS, USDA monitors the production and distribution of food through wholesale channels to ensure that the levels of contamination in the product are below the DILs.
Department of Defense (DoD)
Subject to the approval of the Secretary of Defense, DoD provides Defense Support of Civil Authorities in response to requests for assistance during incidents that happen within the United States. DoD also provides immediate assistance under Immediate Response Authority for any civil emergency that may require immediate action to save lives, prevent human suffering, or mitigate great property damage.
14 FDA has adopted DILs as guidance levels for radionuclide activity concentration to help determine whether domestic or imported food presents a safety concern. See Compliance Policy Guides, § 560.750, Radionuclides in Imported Foods —Levels of Concern, http://www.fda.gov/ICECI/ComplianceManuals/CompliancePolicyGuidanceManual/ucm074576.
15 NARAC is one of the assets that support IMAAC requests.
17 EPA takes over management of the FRMAC when the emergency response phase of the incident is over and the recovery phase has begun. See http://www.nnsa.energy.gov/aboutus/ourprograms/emergencyoperationscounterterrorism/respondingtoemergencies-0-1.
Federal agencies define three phases in structuring the response to a radiological emergency in the United States: early (or emergency), intermediate, and late (or recovery) phase. These phases are represented by the activities performed rather than by precise time periods; some overlap between phases may exist.
The early phase lasts from several hours to days from initiation of the nuclear reactor accident. During this phase, the ability to assess radiological conditions is often limited, but immediate decisions for protective actions may be required to protect populations from exposure to direct radiation and inhalation from an airborne plume. Such actions are generally based on plant conditions and projected doses and include evacuation and sheltering in place (possibly supplemented by KI) and are prompted by comparing expected radiation levels to a PAG. Restrictions on the consumption and use of potentially contaminated food and water may be initiated during this phase.
The intermediate phase may last from weeks to months. During this phase the nuclear reactor has been brought under control and there are no further significant radioactive releases that would exceed the PAGs. During this phase, environmental measurements of radioactivity are made available for use as a basis for decisions on additional protective actions. Doses may accrue in this phase from deposited, resuspended, and ingested radioactive material. The protective actions issued during this phase are relocation18 and decontamination to reduce radiation levels in the environment. Similar to the emergency phase, protective actions are prompted by comparing radiation levels to a PAG.
The late phase can last from months to years. It begins when actions have been initiated to remediate contaminated areas and allow relocated populations to reoccupy or resettle.19 Recovery ends when all actions have been completed.
18 Relocation is frequently issued during the intermediate and recovery phases. It involves the removal or continued exclusion of people from areas deemed contaminated to avoid low-level, chronic radiation exposure.
19 The term reoccupancy refers to moving back to the area that was evacuated at the time of the nuclear emergency. The term resettlement refers to living in a new area after being permanently relocated.