For programmatic reasons, ARL's work in this area is divided into three pieces corresponding to before-event preparation, during-event response, and post-event assessment.

Emergency Preparation

ARL serves as a provider of meteorological and air pollution guidance to other agencies involved in the planning process related to technological disasters. In general, the question addressed is "What will happen if . . . And what should be done?" The goal is to plan response activities to minimize risk and damage, and to help assess risk in time to avoid dangerous situations. In this regard, ARL works with many government agencies (including EPA, NRC, NASA, DOD, DOE, DOT, DHS, FBI) involved in the use or atmospheric transport of hazardous materials.

The scales involved are from local to continental, with some activities stretching to global. Of special relevance is the ARL specialization in the short-range dispersion of pollutants, especially heavy gases which tend to be greatly influenced by terrain and atmospheric stability. Several ARL groups (Research Triangle Park, Idaho Falls, Las Vegas)are actively involved in research on the dispersion and transportof heavy gases released near the surface. ARL figures prominently in the management and operation of the Hazmat Spill Test Facility located on the Nevada Test Site of the Department of Energy, near Las Vegas, NV.

In particular, ARL specializes in the provision of dispersion and possible exposure guidance to assist in planning responses by other agencies:

• to the Nuclear Regulatory Commission at their Washington DC Headquarters, related to power reactor accidents
• to the Department of Homeland Security/FEMA related to terrorist incidents
• to the Department of Energy at their Idaho Falls, Las Vegas, and Oak Ridge locations, related to safety of handling and testing nuclear materials
• to the Nuclear Emergency Search Team (NEST) and to the Federal Radiological Monitoring and Assessment Center (FRMAC) program at Las Vegas, related to the response to nuclear emergencies
• to the Department of Energy in Las Vegas, related to the need to maintain a capability to conduct experiments with nuclear materials
• to the agencies leading the Interagency Nuclear Safety Review Panel (NASA, DOD, DOE, NRC, and EPA), related to the launching of radioactive payloads on space vehicles from the USA and Russia
• and to DOE field offices concerned with the health and safety of on-site employees and the general public.

Emergency Response

ARL provides real-time forecasts that are specially tailored to assist in the management of emergencies following nuclear and volcanic disasters that inject material into the atmosphere. The same capabilities have been employed extensively in other situations, notably in the context of the oil fire smoke situation following the Gulf War. ARL capabilities are coupled with those of the NOAA National Centers for Environmental Prediction, which serves as the round-the-clock mechanism for assuring adequate NOAA response in the event of an accident. The ARL role is to provide the best available products for use in this coupled emergency response service, and to interact with other agencies as necessary to address special needs.

ARL products are especially relevant in the management of nuclear emergencies arising from the unexpected release of radioactivity into the air, whether from (a) a commercial nuclear power reactor, (b) a terrorist incident, (c) a military accident, (d) a test or accident at a site under the jurisdiction of the Department of Energy, or (e) a test prohibited under the Comprehensive Test Ban Treaty.

At the international level, ARL and NCEP serve as a Regional Specialized Meteorological Center of the World Meteorological Organization, one of five such centers spread around the world. The U.S. and Canadian RSMCs act in close coordination, and conduct regular comparisons of forecast products to ensure that these two groups can serve as a team in the event of an actual accident requiring international attention.

Relevant Links

• NOAA ARL's Contribution to Homeland Security

Emergency Assessment

The Regional Specialized Meteorological Center discussed above is designed to provide warning capabilities for nuclear accidents. The same modeling capabilities are applicable to atmospheric hazardous materials of all kinds. Of special interest are chemicals with long-term accumulated ("chronic") consequences, such as potential mutagens and teratagens. In this case, the need is for assessment of long-term impact rather than for short-term forecasting. The relevant ARL activity is, therefore, distributed among several groups. At Research Triangle Park, the current focus is on airborne particles, persistent organic pollutants, trace metals, endocrine disrupters, and other substances that jeopardize health and ecosystems. This aspect of the ARL Emergency Preparedness activity is described in detail among the documents assembled under the Weather and Air Quality theme. This is an example of how the elements of the ARL scientific program are not clearly pigeon-holed into neat thematic bins. Instead, the growth of scientific understanding and the requirements of policy and regulatory communities dictate programmatic development, some of which can clearly be related to assessment of emergencies, and some of which is clearly more related to Air Quality.

ARL capabilities have been directly involved in the post-event assessment of the consequences of several disasters, each in collaboration with other agencies.