Homeland Security:

First Responders' Ability to Detect and Model Hazardous Releases in Urban Areas Is Significantly Limited

GAO-08-180: Published: Jun 27, 2008. Publicly Released: Jun 27, 2008.

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First responders are responsible for responding to terrorist-related and accidental releases of CBRN materials in urban areas. Two primary tools for identifying agents released and their dispersion and effect are equipment to detect and identify CBRN agents in the environment and plume models to track the dispersion of airborne releases of these agents. GAO reports on the limitations of the CBRN detection equipment, its performance standards and capabilities testing, plume models available for tracking urban dispersion of CBRN materials, and information for determining how exposure to CBRN materials affects urban populations. To assess the limitations of CBRN detection equipment and urban plume modeling for first responders' use, GAO met with and obtained data from agency officials and first responders in three states.

While the Department of Homeland Security (DHS) and other agencies have taken steps to improve homeland defense, local first responders still do not have tools to accurately identify right away what, when, where, and how much chemical, biological, radiological, or nuclear (CBRN) materials are released in U.S. urban areas, accidentally or by terrorists. Equipment local first responders use to detect radiological and nuclear material cannot predict the dispersion of these materials in the atmosphere. No agency has the mission to develop, certify, and test equipment first responders can use for detecting radiological materials in the atmosphere. According to DHS, chemical detectors are marginally able to detect an immediately dangerous concentration of chemical warfare agents. Handheld detection devices for biological agents are not reliable or effective. DHS's BioWatch program monitors air samples for biothreat agents in selected U.S. cities but does not provide first responders with real-time detection capability. Under the BioWatch system, a threat agent is identified within several hours to more than 1 day after it is released, and how much material is released cannot be determined. DHS has adopted few standards for CBRN detection equipment and has no independent testing program to validate whether it can detect CBRN agents at the specific sensitivities manufacturers claim. DHS has a mission to develop, test, and certify first responders' CB detection equipment, but its testing and certification cover equipment DHS develops, not what first responders buy. Interagency studies show that federal agencies' models to track the atmospheric release of CBRN materials have major limitations in urban areas. DHS's national TOPOFF exercises have demonstrated first responders' confusion over competing plume models' contradictory results. The Interagency Modeling and Atmospheric Assessment Center (IMAAC), created to coordinate modeling predictions, lacks procedures to resolve contradictory predictions. Evaluations and field testing of plume models developed for urban areas show variable predictions in urban environments. They are limited in obtaining accurate data on the characteristics and rate of CBRN material released. Data on population density, land use, and complex terrain are critical to first responders, but data on the effects of exposure to CBRN materials on urban populations have significant gaps. Scientific research is lacking on how low-level exposure to CBRN material affects civilian populations, especially elderly persons, children, and people whose immune systems are compromised.

Recommendations for Executive Action

  1. Status: Closed - Not Implemented

    Comments: DHS notes that since 2008, DHS and several other federal agencies have been working together with the National Science and Technical Council (NSTC) Subcommittee on Standards. The subcommittee has been chartered to develop a roadmap of the development of chemical, biological, radiological and nuclear (CBRN) detection equipment and identify needed performance standards for this equipment. This would include identifying which agency would support such standards development. While DHS and others are working on addressing the issue of performance standards, it has not yet been determined which agencies should have the missions and responsibilities to develop, independently test and certify detection equipment for first responders to use to detect hazardous material in the atmosphere. Thus while DHS continues its efforts in this area, we consider this recommendation not yet fully implemented.

    Recommendation: The Secretary of Homeland Security should reach agreement with Department of Defense (DOD), Dertment of Energry (DOE), Environmental Protection Agency (EPA), and other agencies involved with developing, testing, and certifying CBRN detection equipment on which agency should have the missions and responsibilities to develop, independently test, and certify detection equipment that first responders can use to detect hazardous material releases in the atmosphere.

    Agency Affected: Department of Homeland Security

  2. Status: Closed - Not Implemented

    Comments: DHS's Science and Technology Director is working with other federal agencies to develop standards through its co-chairmanship of the NSTC SOS. According to DHS, the specifications incorporated into such standards and the associated test protocols, are needed to guide the efforts of manufacturers and equipment developers, among other things. However, DHS states while it cannot comment on the future test, evaluation, and certification efforts of other agencies, it is committed to those efforts for CBRN detectors purchased with DHS grant funds. Thus, while DHS continues its efforts in this area, this recommendation is not fully implemented

    Recommendation: The Secretary of Homeland Security should ensure that manufacturers' claims are independently tested and validated regarding whether their commercial off-the-shelf CBRN detection equipment can detect given hazardous material at specific sensitivities.

    Agency Affected: Department of Homeland Security

  3. Status: Closed - Not Implemented

    Comments: DHS notes that while IMAAC coordinates federal plume modeling, it is not intended to replace or supplant the atmospheric transport and dispersion modeling activities already in place to meet agency-specific mission needs. DHS has taken several actions, including effort to refine the concept of operations for different types of atmospheric releases. For example, an IMAAC interagency working group is developing incident specific annexes to the IMAAC standard operating procedures (SOP). Also efforts are underway to delineate responsibilities for a type-specific incident technical review of IMAAC plume modeling products. In addition, the IMAAC SOP was updated to provide guidance on the type and scales of events for which IMAAC assistance would be warranted. DHS has also undertaken several other efforts and plans others. However, to date, DHS has not fully implemented this recommendation.

    Recommendation: The Secretary of Homeland Security should refine IMAAC's procedures by working with other federal, state, and local agencies to (1) develop common/joint IMAAC emergency response practices, including procedures for dealing with contradictory plume modeling information from other agencies during a CBRN event; (2) refine the concept of operations for chemical, biological, and radiological releases; and (3) delineate the type and scale of major CBRN incidents that would qualify for IMAAC assistance.

    Agency Affected: Department of Homeland Security

  4. Status: Closed - Not Implemented

    Comments: DHS has funded some research efforts aimed at addressing deficiencies in meteorological information, plume models and data sets to support plume model validation.DHS states that it has also been working with DHS customers and representatives from the first responder community; a number of plume modeling gaps have been identified.DHS notes that programs to address these gaps are ongoing. For example, an effort is underway to improve the dense gas algorithms for large-scale chemical releases, such as a tanker car filled with liquid chlorine. Also, field experiments have been conducted to gather field data that could be sued to support validation of existing models. While DHS is involved in several efforts, these are still ongoing. Therefore this recommendation Is not fully implemented.

    Recommendation: The Secretary of Homeland Security should, in conjunction with IMAAC, work with the federal plume modeling community to accelerate research and development to address plume model deficiencies in urban areas and improve federal modeling and assessment capabilities. Such efforts should include improvements to meteorological information, plume models, and data sets to evaluate plume models.

    Agency Affected: Department of Homeland Security


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