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TECHNOLOGY AARMS Vol. 6, No. 1 (2007) 57–63 Nuclear emergency planning in the United States NATALIA GERGELICS Somogy County Disaster Management Directorate, Kaposvár, Hungary Although construction and operation of nuclear power plants are closely monitored and regulated by the NRC, an accident is possible. The potential danger from an accident at a nuclear power plant is exposure to radiation. That’s why Emergency Planing Zones (EPZ) were established. Generally, the plume exposure pathway EPZ for nuclear power plants shall consist of an area about 10 miles (16 km) in radius and the ingestion pathway EPZ shall consist of an area about 50 miles (80 km) in radius. In this article, I present two state regulations of nuclear emergency planning in the USA, in Oregon and in California. Introduction Since 1980, each utility that owns a commercial nuclear power plant in the United States has been required to have both an onsite and offsite emergency response plan as a condition of obtaining and maintaining a license to operate that plant. Onsite emergency response plans are approved by the Nuclear Regulatory Commission (NRC). Offsite plans (which are closely coordinated with the utility’s onsite emergency response plan) are evaluated by the Federal Emergency Management Agency (FEMA) and provided to the NRC, who must consider the FEMA findings when issuing or maintaining a license. Federal law establishes the criterion for determining the adequacy of offsite planning and preparedness, because it must be determined to protect the public health and safety by providing reasonable assurance. That appropriate measures can be taken offsite in the event of a radiological emergency. Although construction and operation of nuclear power plants are closely monitored and regulated by the NRC, an accident is possible. The potential danger from an accident at a nuclear power plant is exposure to radiation. This exposure could come from the release of radioactive material from the plant into the environment, usually characterized by a plume (cloud-like) formation. The area of the radioactive release may affect by the amount released from the plant, direction and speed of wind and weather conditions (rain, snow, etc.), which would quickly drive the radioactive material to the ground, hence causing increased deposition of radionuclides. Received: December 12, 2006 Address for correspondence: NATALIA GERGELICS Somogy County Disaster Management Directorate, Kaposvár, Hungary E-mail: [email protected] N. GERGELICS: Nuclear emergency planning in the U.S. If a release of radiation occurs, the levels of radioactivity will be monitored by authorities from U. S. Federal and State governments, and the utility, to determine the potential danger in order to protect the public. The following is the principal part governing emergency preparedness: § 50.47 Emergency plans “(1) Primary responsibilities for emergency response by the nuclear facility license and by State and local organizations within the Emergency Planning Zones (EPZ) have been assigned, the emergency responsibilities of the various supporting organizations have been specifically established, and each principal response organization has staff to respond and to augment its initial response on a continuous basis. (2) Generally, the plume exposure pathway EPZ for nuclear power plants shall consist of an area about 10 miles (16 km) in radius and the ingestion pathway EPZ shall consist of an area about 50 miles (80 km) in radius. The exact size and configuration of the EPZs surrounding a particular nuclear power reactor shall be determined in relation to local emergency response needs and capabilities as they are affected by such conditions as demography, topography, land characteristics, access routes, and jurisdictional boundaries. The size of the EPZs also may be determined on a case-bycase basis for gas-cooled nuclear reactors and for reactors with an authorized power level less than 250 MW thermal. The plans for the ingestion pathway shall focus on such actions as are appropriate to protect the food ingestion pathway.”1 History of regulation2 After the Three Mile Island accident (1980), U. S. Congress passed a law requiring, that every U.S. nuclear plant develop and test periodically on-site and off-site comprehensive emergency response plans. Local, state, and national officials are included in the plans and in periodic drills and exercises. At the plants, the people involved in emergency preparedness now number a few hundred. The NRC approves on-site plans and the NRC coordinates with FEMA determine “reasonable assurance”, that off-site plans could be implemented in an emergency. Every two years, each nuclear plant conducts a full-scale emergency exercise involving a confidential emergency scenario to be handled by on-site and off-site emergency response organizations, including plant employees, local law enforcement, fire departments, radiological monitoring teams, among others. The NRC evaluates performance of the on-site plan and FEMA the off-site plan. Necessary improvements are identified to be corrected. In alternate years, plants conduct training drills, frequently 58 AARMS 6(1) (2007) N. GERGELICS: Nuclear emergency planning in the U.S. unannounced, involving such key factors as coordination, communications, assessment of emergency, medical, and fire brigade response, and radiation dose measurement. Federal guidelines require nuclear plants to provide protective responses for communities in 10-mile and 50-mile emergency planning zones (EPZ).3 Residents in the 10-mile zone are provided information explaining radiation and telling them, what to do and where to go in the event of an emergency. They would be notified to tune in to the National Emergency Alert System (sirens, tone-alert radios). They are also told about protective actions, including the possibility of orderly sheltering, evacuation in case of a potentially serious accident, and, if recommended, the taking of potassium iodide to block the thyroid from the effects of radiation. In the 50-mile zone, state agencies formulate plans for radiological monitoring and for protecting residents against consumption of possibly contaminated food and water. Following the terrorist attacks of Sept. 11, 2001, the NRC reviewed requirements for nuclear plant security. New requirements are focused in part on emergency preparedness at plant sites in response to terrorist threats. Industry, in coordination with the NRC and FEMA, has implemented these measures. The guidelines were refined to address such issues as on-site evacuation, public communications, emergency staffing, procedures and plans in the specific context of a terrorist attack. I would like to present two state regulations in USA. Emergency planning in Oregon4 Triggering the state/county emergency response5 There are three levels of “radiological emergencies”, which could occur during the Emergency Phase at Hanford: Alert, Site Area Emergency, and General Emergency. The least severe is an Alert. That means the facility is less safe than normal. A small release of radioactive materials could occur. Onsite workers may need protection; people offsite don’t. If an Alert is declared at Hanford, the state of Oregon will be contacted within minutes. The Site Area Emergency is the threat of a release of radioactive material. No actions will be required of the general public. A General Emergency is the most severe level. It means there has been or likely will be a release of radioactive materials. Some, if not all, people within the Plume Zone will be told to take protective action. Experts agree that evacuation planning beyond 10 miles from the site for any Hanford incident is unnecessary. AARMS 6(1) (2007) 59 N. GERGELICS: Nuclear emergency planning in the U.S. Oregon’s response to a Hanford Emergency6 USDOE-Richland or Energy Northwest contacts the Duty Officer at the Oregon Department of Energy (Oregon Energy) that an “emergency” has been declared. At this point, Oregon Energy’s chief concern is providing accurate information to the public and monitoring the event. The Duty Officer notifies the two counties and state radiological monitoring teams go on standby. Oregon Energy tells other state emergency responders and Umatilla and Morrow counties to stand by. As the lead agency, Oregon Energy keeps in contact with USDOERichland and Energy Northwest and stays abreast of events. Oregon Energy also works with USDOE-Richland or Energy Northwest and Washington state on public information. Few nuclear incidents ever get beyond the Alert stage. If USDOERichland or Energy Northwest elevates the situation to a Site Area Emergency, Oregon Energy is told immediately. Oregon Energy alerts the two counties and activates Oregon’s Emergency Coordination Center (ECC) in Salem. Salem response agencies, like the National Guard and the Agriculture and Transportation departments and State Police, send staff to the ECC. If needed, the Oregon Health Division sends field teams to the two counties to begin radiation monitoring. The governor and state technical advisors stay in touch with USDOE-Richland or Energy Northwest and decide what, if any, protective actions should be taken in Oregon. Even in a Hanford General Emergency, Oregon’s response would continue to focus on public information and radiation monitoring in the two counties. However, let’s assume that some airborne radioactive materials from Hanford reached Umatilla and Morrow counties. This is how the state would respond: Field teams would identify contaminated and potentially contaminated areas. The counties would activate Emergency Operations Centers in Pendleton and Heppner. Offduty county emergency response staff would be contacted and some may be called to duty. The Salem ECC Public Information team would work with the counties, Washington state, and USDOE-Richland or Energy Northwest to issue news releases, governor’s statements and other general information about the state’s response to the emergency. The counties would help the Oregon Department of Agriculture notify commercial dairies, farmers and food processors of the emergency and actions to be taken. Again, it’s important to remember that the potential for human ingestion of contamination on crops and water is not likely, but it is the state’s and the two counties’ chief concern. 60 AARMS 6(1) (2007) N. GERGELICS: Nuclear emergency planning in the U.S. Planning zones Emergency response planning involves two zones7 in Oregon: the “Plume Zone” and the “Ingestion Zone.” The Plume Zone is within a 10-mile or smaller radius of the potential accident site. Each Hanford facility has its own Plume Zone. The size is based on how far a particular substance could be dispersed in a particular form. The hazard is radioactive materials in an invisible cloud or plume, carried from the accident by the wind. People can be at risk if they are exposed to the plume or inhale the radioactive materials in it. To avoid the plume, people within the Plume Zone must take shelter or leave the area. Beyond the Plume Zone, the plume still carries widely scattered radioactive materials which, in time, will be left on the earth’s surface. A plume doesn’t stay small, compact or intact. It’s diluted by clean air and dissipated by changing winds. The Ingestion Zone goes out to 50 miles. It’s the area within which people could be at risk if they eat or drink contaminated food or water. Contamination occurs when airborne radioactive materials come to rest on crops, pasture, gardens, lakes and rivers. For example, people can be affected if they drink milk from a cow that ate contaminated grass. Beyond 50 miles, it’s believed that the risk of contamination from a nuclear accident’s “fallout” is very slight. The health effects of exposure to radioactive material vary from person to person. Nuclear Power in California8 The nuclear power industry uses radioactive materials, such as uranium, as fuel for the generation of electricity. Before operation of the nuclear power plants in California, the NRC conducted lengthy plant design review, location selection, operations and plant safety features in coordination with other federal, state and regional authorities to ensure that comprehensive safety standards were met. There are two operating nuclear power plant sites in California: • Diablo Canyon9 in San Luis Obispo County has two operating units. • San Onofre Nuclear Generating Station10 in San Diego County has two operating units. A third unit at San Onofre is in a “safe storage” mode.11 AARMS 6(1) (2007) 61 N. GERGELICS: Nuclear emergency planning in the U.S. Nuclear Power Plant Safeguards Triple-safeguard features prevent the release of radiation: 1. Metal tubes or rods, which contain the fuel pellets, act as the first barrier. 2. The fuel rods are contained in the reactor vessel within 8-inch thick steel walls. 3. An airtight containment building is constructed of metal and reinforced concrete walls, totaling more than four-feet thick. Control and safety systems within the plant are designed to overlap for safety. Automatic systems have the ability to shut down the reactors within seconds if monitoring devices detect unusual conditions, such as an excessive heat build up. Should any individual safety component fail there are back-up systems that take over immediately. The NRC has resident inspectors assigned to each plant site. The inspectors oversee plant operations and ensure compliance with regulations governing operational and occupational safety. There are automatic communications systems that contact the State Warning Center in Sacramento if certain conditions, such as an earthquake or certain plant conditions, occur. The State Warning Center will be able to contact key personnel needed in an emergency. Nuclear Power Plant Emergency Preparedness Planning, preparing, and training for nuclear power plant emergencies are also part of the safeguards. Federal, state, and local emergency management agencies work with the utilities to ensure that nuclear power plants are safe and that each agency and utility has an effective emergency plan describing the actions to be taken in response to an emergency. Residents and businesses near a nuclear power plant should prepare a disaster plan for all emergencies including nuclear power plant emergencies and should become familiar with the emergency preparedness information. The NRC has primary jurisdiction over nuclear facilities in the United States and it works closely with state and local emergency agencies. Planning Zones12 A series of zones has been established around each nuclear power plant to clearly identify the required activities in the event of an accident. Although three specific zones are identified, efforts to protect public health and safety and the environment are made without regard to whether particular areas are inside or outside of these zones. • The Emergency Planning Zone is an approximate 10-mile radius around the plants. Plans for this zone are in place to protect people, property, and the environment from the effects of exposure to a radioactively contaminated plume. 62 AARMS 6(1) (2007) N. GERGELICS: Nuclear emergency planning in the U.S. • The Ingestion Pathway Zone covers an approximate 50-mile radius around the plant. In this zone, plans are in place to mitigate the effects on of radioactive contamination to agriculture, and food processing and distribution. • Within Public Education Zones, including areas approximately 35 miles from the plants, educational materials are distributed to inform the public about nuclear power plant operations, what to expect in the event of an accident, and what plans are in place for public protection. The utilities that operate the power plants are required to publish and disseminate information for residents and transient populations. Notes and references 1. NRC Regulations Title 10, Code of Federal Regulations, http://www.nrc.gov/reading-rm/doc-collections/cfr/part050/part050-0047.html (U.S. Nuclear Regulatory Commission) 2. http://www.tnema.org/EP/EP_NPP.htm 3. http://www.nrc.gov/what-we-do/emerg-preparedness/protect-public/planning-zones.html 4. www.oregon.gov 5. http://www.oregon.gov/ENERGY/NUCSAF/triggering.shtml 6. http://www.oregon.gov/ENERGY/NUCSAF/orresp.shtml 7. http://www.oregon.gov/ENERGY/NUCSAF/epz.shtml 8. www.oes.ca.gov 9. Operated by Pacific Gas & Electric. 10. Operated by Southern California Edison. 11. This means that the nuclear fuel has been removed and safely stored. 12. http://www.oes.ca.gov/Operational/OESHome.nsf AARMS 6(1) (2007) 63